Fusarium-resistant lettuce plants

Abstract

The present invention relates to a lettuce plant (Lactuca sativa L.) containing a resistance QTL conferring dual resistance to Fusarium oxysporum lactucae specialis races Fol-1 and Fol-4, the QTL being located on chromosome 7. The invention further provides seeds, progeny, propagation material, and food products derived from the plant.

Description

[Technical Field]

[0001] The present invention relates to plants and plant parts, particularly lettuce plants (Lactuca sativa L.), having a single quantitative trait locus (QTL7.1) from Lactuca serriola that confers resistance to Fusarium oxysporum form Lactucae specialis (Fol-1) and / or race 4 (Fol-4), and in particular dual resistance to Fol-1 and Fol-4. The invention further relates to plant parts, seeds, propagation material, progeny of the plants, and the use of the plants as germplasm in breeding for at least Fol-1 and / or Fol-4 resistance or dual Fol-1 and Fol-4 resistance. This QTL7.1 was identified in a lineage of the wild species Lactuca serriola and introgressed into Lactuca sativa. [Background technology]

[0002] A common lettuce disease worldwide is Fusarium wilt, which was first observed in Japan in 1955. Fusarium wilt has since been confirmed in the United States, Taiwan, Iran, Portugal, Italy, and Brazil. Initially, three races (Fol-1, Fol-2, and Fol-3) of the pathogenic Fusarium oxysporum f.sp. lactucae were identified in lettuce, and a fourth race, Fol-4, was identified in the Netherlands in 2017 (Gilardi et al. 2017, A new race of Fusarium oxysporum f.sp. lactucae of lettuce. Plant Pathol 66:677-688). Gilardi et al. referred to this race as "Race 4", and the ISF subsequently adopted this race as a new Fol:4 race, with Gilard et al.'s race 04750888 representing type Fol:4 (see the World Wide Web at http: / / worldseed.org / document / differential-sets-fol-race-4 / ).

[0003] These four races, referred to herein as Fol-1, Fol-2, Fol-3, and Fol-4 (or Fol:1, Fol:2, Fol:3, and Fol:4 by ISF), can be distinguished, for example, based on phenotypes in differential lettuce hosts published by ISF (on the World Wide Web at http: / / worldseed.org / document / differential-sets-fol-race-4 / ) and race-specific PCR. To distinguish the resistance response of races in host varieties, the CPVO protocol, described on the World Wide Web at cpvo.europa.eu, is used.

[0004] Race Fol-4 is becoming increasingly prevalent. Claerbout et al. (2022, http: / / doi.org / 10.1111 / ppa.13668) reported that 91% of Fusarium isolates found in commercial lettuce greenhouses in Belgium belonged to race Fol-4, and only 6% belonged to race Fol-1. They also found that the cultivar Patriot was a good cultivar for identifying Fol-4.

[0005] Seki et al. (2020, Euphytica 216:174) identified two QTLs conferring resistance to race Fol-1 in crisphead lettuce cultivar (L. sativa) VI185 and mapped them to chromosomes 7 (qFOL7.1) and 8 (qFOL8.1). qFOL7.1 was mapped to chromosome 7 of the V8 genome at 85.69 Mb to 100.59 Mb (shoot) and 87.943 Mb to 98.36 Mb (root) (see Table 2 herein). In contrast, the current QTL7.1 is located at approximately 61.49 Mb to 66.46 Mb of the V8 genome (data not shown).

[0006] Similarly, in Spain, outbreaks of race Fol-4 have been reported in recent years, as confirmed by race-specific PCR and virulence testing ( Plant Dis. 2023 Feb 12. doi:10.1094 / PDIS-12-22-2819-PDN; advance online publication).

[0007] U.S. Patent Application Publication No. 2022 / 0346339 describes a lettuce cultivar designated NUN06240 as containing resistance to race 4 and race 1. Applicant compared the chromosome 7 SNP haplotype of NUN06240 with the SNP donor haplotype of QTL7.1 and found that they were significantly different. Applicant further confirmed that two separate loci are responsible for resistance to race 1 and race 4 in NUN06240, and that these two loci are not located on chromosome 7. Thus, NUN06240 does not contain instant QTL7.1.

[0008] Garibaldi et al. 2004 (Crop Protection 23:845-851) describe "one Italian isolate (FOL 4)" in virulence testing. On page 850 (left column, discussion), this isolate is referred to as a "race 1" isolate (i.e., referred to herein as Fol-1). Fol-4 did not exist at the time of publication, and this name was likely assigned simply to number the isolate in the collection, not with any reference to race.

[0009] Murray et al. (2021, HortScience 56(12):1552-1564) described tests to identify resistance in Florida to race Fol-1, which was first detected in Florida in 2017. At the time, Fol-4 was not present in the United States. Murray et al. primarily screened Florida-adapted Lactuca sativa cultivars for resistance to Fol-1, but also included several wild Lactuca accessions. However, among the wild Lactuca accessions tested, no resistance to the underlying symptoms of Fol-1 was identified (p. 1562, right column, lines 1-3).

[0010] Mestdagh et al. (2023, Front. Plant Sci., Volume 14-2023, / / doi.org / 10.3389 / fpls.2023.1272136) developed a PCR assay to distinguish between races Fol-1 and Fol-4. Summary of the Invention [Means for solving the problem]

[0011] Given the rapid spread of race Fol-4, there is an urgent need to develop lettuce plants that are resistant to race Fol-4, which has not yet been identified.

[0012] The present invention is further described in the following examples, which are for illustrative purposes only and should not be construed as limiting the invention in any way. In these examples, reference is made to the following figures: [Brief explanation of the drawings]

[0013] [Figure 1] Photograph taken 12 days after inoculation with Fol-4; plants of L. sativa lines containing QTL7.1 are indicated by black boxes, demonstrating high resistance to race Fol-4. [Figure 2] Photograph taken 12 days after inoculation with Fol-1; plants of L. sativa lines containing QTL7.1 are indicated by black rectangles, indicating moderate resistance to race Fol-1. [Figure 3] Blast output of SEQ ID NO: 1 (query) against the L. sativa V11 genome (target); SNP_01 is located at nucleotide 64382881 on chromosome 7 and is a G (guanine) in the L. sativa reference genome V11. [Figure 4]Schematic diagram of chromosome 7 and the location of QTL7.1, with QTL7.1 flanking markers (SNP_01 and SNP_10) and the QTL7.1 peak marker (not to scale); the peak marker is SNP_07, markers SNP_01 to SNP_06 are "upstream" of SNP_07 on the chromosome, and markers SNP_08 to SNP_10 are "downstream" of SNP_07 on the chromosome. DETAILED DESCRIPTION OF THE INVENTION

[0014] general definition The indefinite article "a" or "an" does not exclude the presence of a plurality of elements unless the context clearly requires that only one element is present. Thus, the indefinite article "a" or "an" usually means "at least one."

[0015] As used herein, the term "plant" includes a whole plant or any part or derivative thereof, such as a plant organ (e.g., harvested or unharvested leaves, seeds, etc.), a plant cell, a plant protoplast, a plant cell or tissue culture from which a whole plant can be regenerated, a plant callus, a plant cell mass, a plant part such as an embryo, pollen, an ovule, an ovary (e.g., a harvested tissue or organ, e.g., a harvested head or part thereof), a flower, a leaf, a seed, a clonally propagated plant, a root, a stem, a root tip, and the like. Also included are any developmental stages, such as seedlings, immature, and mature. When "seeds of a plant" are referred to, this refers to seeds from which a plant can be grown, or to seeds produced on a plant after self- or cross-fertilization.

[0016] A "plant variety" is a group of plants within the same plant taxon of the lowest known order that can be defined based on the expression of characteristics resulting from a particular genotype or combination of genotypes (whether or not the conditions for recognition of plant breeders' rights are met), that can be distinguished from any other group of plants by the expression of at least one of these characteristics, and that can be considered an entity because it can be multiplied without any change. Thus, the term "plant variety" cannot be used to refer to a group of plants, even if they are of the same species, that are all characterized by the presence of one or a few loci or genes (or phenotypic characteristics resulting from these particular loci or genes), but that may otherwise differ significantly from each other with respect to other loci or genes. Thus, for example, a plant defined solely by the presence of one QTL is not a plant variety because the thousands of other genes that define the plant variety are not defined, and a plant defined solely by the presence of QTL7.1 is not uniform and stable with respect to these thousands of genes and the characteristics conferred by these genes. QTL7.1 can be used to develop many different lettuce varieties, for example, lettuce varieties that are uniform and stable with respect to physiological and morphological traits such as leaf size or shape, leaf margin and color, and that also contain QTL7.1.

[0017] The term "allele" refers to any one or more alternative forms of a gene at a particular locus, all of which are associated with one trait or characteristic at that locus. In diploid cells of an organism, alleles of a given gene are located at specific positions or loci on a chromosome. One allele is present on each chromosome of a pair of homologous chromosomes. A diploid plant species may contain many different alleles at a particular locus. These may be the same allele of the gene (homozygous) or two different alleles (heterozygous). Thus, for example, reference may be made herein to the "Fol-4 and / or Fol-1 resistance allele" of QTL7.1.

[0018] The term "gene" refers to a (genomic) DNA sequence that comprises a region that is transcribed into a messenger RNA molecule (mRNA) within a cell (the transcribed region) and an operably linked regulatory region (e.g., a promoter). Thus, different alleles of a gene are different alternative forms of the gene, which can be in the form of, for example, differences in one or more nucleotides of the genomic DNA sequence (e.g., the promoter sequence, the exon sequence, the intron sequence, etc.), the mRNA, and / or the amino acid sequence of the encoded protein.

[0019] The term "locus" (plural loci) refers to the specific location or position on a chromosome where, for example, a QTL, gene, or genetic marker is found. Thus, the Fol-4 and / or Fol-1 resistance locus refers to the position in the L. sativa genome where QTL7.1 is found.

[0020] A "quantitative trait locus" or "QTL" is a chromosomal locus that encodes one or more alleles that influence the expressivity of a continuously distributed (quantitative) phenotype. The quantitative trait locus conferring Fol-4 and / or Fol-1 resistance is designated herein as QTL7.1.

[0021] "Lactuca sativa genome," "physical location in the lettuce genome," and "chromosome 7" refer to the physical genome, physical chromosome, and physical location on the chromosome of reference genome V11. Thus, for example, SNP_01 is located at the nucleotide (or "base") physically located at nucleotide 64,382,881 on chromosome 7, as shown in Figure 3.

[0022] "Physical distance" between loci (e.g., between molecular markers and / or between phenotypic markers) on the same chromosome refers to the actual physical distance expressed in bases or base pairs (bp), kilobases or kilobase pairs (kb), or megabases or megabase pairs (mb).

[0023] The "genetic distance" between loci (e.g., between molecular markers and / or phenotypic markers) on the same chromosome is measured by the crossover frequency or recombination frequency (RF) and is given in centimorgans (cM). 1 cM corresponds to a recombination frequency of 1%. If no recombinants can be found, the RF is zero and the loci are physically very close to each other or are identical. The further apart two loci are, the higher the RF.

[0024] An "introgression fragment," or "introgression segment," or "introgression region" refers to a chromosome fragment (or portion or region of a chromosome) that has been introduced into another plant of the same or related species by hybridization or conventional breeding techniques (e.g., backcrossing); i.e., the introgression fragment is the result of a breeding method referred to by the verb "to introgress" (e.g., to backcross). In lettuce, a wild relative of cultivated lettuce can be used to introgress a fragment of the wild genome into the genome of cultivated Lactuca sativa genome L. Thus, such cultivated lettuce plants have a "cultivated Lactuca sativa genome," but this genome includes a fragment on chromosome 7 of the wild L. sativa donor. Thus, for example, provided herein is a cultivated lettuce plant comprising the genome of L. sativa and, in that genome, an introgression fragment on chromosome 7 that confers Fol-4 and / or Fol-1 resistance compared to a cultivated L. sativa genome lacking the introgression fragment (and having cultivated L. sativa chromosome 7 that does not contain the introgression fragment). It is understood that the term "introgression fragment" never includes an entire chromosome, but only a portion of a chromosome. The introgression fragment can be large, for example, three-quarters or half of a chromosome, but is preferably smaller, for example, about 6 Mb or less, about 5 Mb or less, about 4 Mb or less, about 3 Mb or less, about 2.5 Mb or 2 Mb or less, about 1 Mb (equivalent to 1,000,000 base pairs), or about 0.5 Mb (equivalent to 500,000 base pairs), for example, about 200,000 bp (equivalent to 200 kilobase pairs), about 100,000 bp (100 kb), about 50,000 bp (50 kb), or about 25,000 bp (25 kb).

[0025] "Lettuce," or "cultivated lettuce," or "cultivated Lactuca sativa," as used herein, refers to plants of the species Lactuca sativa L. (or seeds from which this plant can grow), and parts of such plants that have been bred by humans for food use and have superior agronomic properties. This includes all cultivated lettuce, including breeding lines (e.g., backcrosses, inbreds), cultivars, and varieties of all kinds. A distinction is generally made between head and non-heading types of lettuce. Heading types include, for example, crisphead, butterhead, and romaine (cos) types, while non-heading types include leaf types. Cultivated lettuce plants are not "wild lettuce" or "wild Lactuca" plants, i.e., plants that generally have significantly inferior yields and agronomic properties compared to cultivated plants, e.g., plants that occur naturally in wild populations.

[0026] "Wild lettuce" or "wild Lactuca" accessions refer to plants of species other than cultivated Lactuca sativa, such as Lactuca virosa, Lactuca serriola, Lactuca saligna, Lactuca perennis, and others. Preferably, such wild lettuce comprises or consists of a Lactuca species that can cross-fertilize with L. sativa, optionally using embryo rescue techniques (Maisonneuve 1987, Agronomique 7:313-319 and Maisonneuve et al. 1995, Euphytica 85:281-285) and / or chromosome doubling techniques (Thompson and Ryder 1961, US Dept Agric Tech Bul. 1224), or methods in which genes can be introduced into L. sativa via a bridge species such as L. serriola.

[0027] A distinction can be made between "somatic cells" and "germ cells," whereby somatic cells are cells other than gametes (e.g., ovules and pollen), germ cells, and gamete cells. Gametes, germ cells, and gamete cells are "germ cells."

[0028] "Tissue culture" or "cell culture" refers to an in vitro composition containing isolated cells of the same or different types, or collections of such cells organized into plant tissue. Lettuce tissue and cell cultures, and the regeneration of lettuce plants therefrom, are known and widely published (see, e.g., Teng et al., HortScience. 1992, 27(9):1030-1032; Teng et al., HortScience. 1993, 28(6):669-1671; Zhang et al., Journal of Genetics and Breeding. 1992, 46(3):287-290).

[0029] "Harvested plant material," as used herein, refers to plant parts (e.g., leaves, leaf parts, or heads separated from the whole plant) that have been collected for further storage and / or further use.

[0030] "Harvested seed" refers to seed harvested from a line or variety, for example, seed produced and harvested after self-fertilization or cross-fertilization.

[0031] "Harvested leaves" or "harvested head" as used herein refers to lettuce leaves, or leaf portions or heads, i.e., plants without the root system, e.g., substantially all (harvested) leaves. The leaves may be whole or partially cut.

[0032] "Progeny" or "progenies" or "descendants," as used herein, refers to offspring, or the first and all further offspring, derived from (obtained from) (can be derived from or obtained from) a plant of the present invention comprising (carrying) QTL7.1 according to the present invention. Progeny can be obtained by regenerating cell or tissue culture or plant parts, or by selfing the plant, or by producing seed from the plant. In further embodiments, progeny can also include lettuce plants obtained by crossing, backcrossing, inserting a gene locus into a plant, or mutation of at least one lettuce plant with another lettuce plant of the same or another variety or (breeding) line, or with wild Lactuca. Progeny can be, for example, the first generation offspring, i.e., progeny are directly derived from, obtained from, obtainable from, or derived from a parent plant, for example, by conventional breeding methods (selfing and / or crossing), or by regeneration, or transformation. However, the term "progeny" generally encompasses additional generations, such as the second, third, fourth, fifth, sixth, seventh, or higher generations, i.e., generations of plants that are derived from, obtained from, obtainable from, or derivable from the previous generation, for example, by conventional breeding methods, regeneration, or genetic transformation techniques. For example, second-generation progeny can be produced from first-generation progeny by any of the methods described above. Doubled haploid plants are also progeny.

[0033] A "plant line" or "breeding line" refers to a plant and its progeny that is highly uniform in plant phenotype. As used herein, the term "inbred line" refers to a plant line that has been repeatedly selfed and is near homozygous for all alleles. Thus, an "inbred line" or "parent line" refers to a plant that has undergone inbred crossing over several generations (e.g., at least 2, 3, 4, 5, 6, 7, or more) to result in a plant line with high uniformity.

[0034] "F1, F2, F3, etc." refer to successive related generations after a cross between two parent plants or parent lines. Plants grown from seeds produced by crossing two plants or lines are called the F1 generation. Selfing the F1 plants produces the F2 generation, etc.

[0035] "Hybrid" refers to the seed harvested from the cross of one plant line or variety with another, and the plants or plant parts grown from said seeds.

[0036] An "F1 hybrid" plant (or F1 hybrid seed) is the generation resulting from the cross of two non-isogenic inbred parent lines. Thus, F1 hybrid seed is the seed from which an F1 hybrid plant grows.

[0037] "Interspecific hybrid" refers to a hybrid produced from the crossing of one species of plant, such as L. sativa, with another species of plant, such as L. serriola.

[0038] "Crossing" refers to the mating of two parent plants. Similarly, "cross-pollination" refers to fertilization by the union of two gametes from different plants.

[0039] "Self-pollination" refers to the self-pollination of a plant, i.e., the combination of gametes from the same plant.

[0040] "Regeneration" refers to the development of a plant from cell culture, or tissue culture, or vegetative propagation.

[0041] "Non-proliferating cells" refer to cells that are not capable of regenerating into a whole plant.

[0042] A "single (or double, or triple) locus transformation (transformation) plant" refers to a plant developed by plant breeding techniques that include or consist of backcrossing, in which essentially all of the desired morphological and / or physiological characteristics of a lettuce plant have been restored in addition to the characteristics of the single locus (or two or three loci) introduced into the plant by, for example, the backcrossing technique.

[0043] "Transgene" or "chimeric gene" refers to a genetic locus containing a DNA sequence that has been introduced into the genome of a lettuce plant by transformation. Plants containing a transgene stably integrated into their genome are called "transgenic plants."

[0044] "Sequence identity" and "sequence similarity" can be determined by aligning two peptide sequences or two nucleotide sequences using a global or local alignment algorithm. Sequences can then be said to be "substantially identical" or "essentially similar" if the sequences, optimally aligned, for example, by the programs GAP, or BESTFIT, or the EMBOSS program "Needle" (using default parameters, see below), share at least a certain minimum percentage of sequence identity (defined further below). These programs use the Needleman and Wunsch global alignment algorithm to align two sequences over their entire length, maximizing the number of matches and minimizing the number of gaps. Generally, default parameters are used, with a gap creation penalty of 10 and a gap extension penalty of 0.5 (for both nucleotide and protein alignments). For nucleotides, the default scoring matrix used is DNAFULL, and for proteins, the default scoring matrix is ​​BLOSUM62 (Henikoff & Henikoff, 1992, PNAS 89, 10915-10919). Sequence alignment and scores in terms of percentage sequence identity can be determined using computer programs such as EMBOSS, available on the World Wide Web at, for example, ebi.ac.uk / Tools / psa / emboss_needle / . Alternatively, sequence similarity or sequence identity can be determined by searching against databases such as FASTA, BLAST, etc.; however, to compare sequence identity, hits should be searched and aligned pairwise.Two proteins or two protein domains, or two nucleic acid sequences have "substantial sequence identity" if the sequence identity percentage is at least 90%, 95%, 98%, 99%, or higher (as determined by Emboss "needle" using default parameters (i.e., gap creation penalty = 10, gap extension penalty = 0.5, using the squaring matrix DNAFULL for nucleic acids and Blosum62 for proteins). When referring to a nucleic acid sequence (e.g., DNA or genomic DNA) having "substantial sequence identity" to a reference sequence or having at least 95%, 96%, 97%, 98%, or 99% nucleic acid sequence identity to a reference sequence, in one embodiment, the nucleotide sequence is considered to be substantially identical to a given nucleotide sequence and may be identified using stringent hybridization conditions. Percent identity is measured, for example, for sequences of the same length, e.g., two sequences 201 nucleotides in length with a SNP at nucleotide 101. This can be done, for example, by pairwise alignment using, for example, Needle, or by BLAST analysis of the sequences against, for example, a genomic or chromosomal sequence. For example, "the SNP nucleotide at nucleotide 101 of SEQ ID NO: 1 or nucleotide 101 in a variant sequence / or the equivalent nucleotide in a variant sequence" refers to the SNP nucleotide at the same position (e.g., nucleotide 101), but the flanking nucleotides to the right and left of the SNP may not be 100% identical to the flanking nucleotides to the left and right of nucleotide 101 of SEQ ID NO: 1. Thus, both sequences of the same length, when aligned, may have only 95%, 96%, 97%, 98%, or 99% sequence identity.

[0045] In another embodiment, a nucleic acid sequence contains one or more mutations compared to a given nucleotide sequence, but can still be identified using stringent hybridization conditions.

[0046] "Stringent hybridization conditions" can be used to identify nucleotide sequences that are substantially identical to a given nucleotide sequence. Stringent conditions are sequence-dependent and will vary in various circumstances. Generally, stringent conditions are selected to be about 5°C lower than the thermal melting point (Tm) of a specific sequence at a given ionic strength and pH. The Tm is the temperature (under a given ionic strength and pH) at which 50% of the target sequence hybridizes to a perfectly matched probe. Typically, stringent conditions will be selected in which the salt concentration is about 0.02 molar at pH 7 and the temperature is at least 60°C. Stringency increases with decreasing salt concentration and / or increasing temperature. Stringent conditions for RNA-DNA hybridization (e.g., Northern blots using a 100-nt probe) include, for example, at least one wash in 0.2×SSC at 63°C for 20 minutes, or equivalent conditions. Stringent conditions for DNA-DNA hybridization (e.g., Southern blots using a 100 nt probe) include, for example, at least one wash (usually two) in 0.2×SSC at a temperature of at least 50° C., usually about 55° C., for 20 minutes, or equivalent conditions.

[0047] The term "Fol-4 and / or Fol-1 resistance QTL7.1" or "QTL7.1" refers to the locus QTL7.1 that has been introgressed from L. serriola onto cultivated lettuce (cultivated L. serriola chromosome 7). Thus, the term "Fol-4 and / or Fol-1 resistance QTL7.1" encompasses QTL7.1 obtained from the seeds deposited herein or their progeny, but also QTL7.1 obtained from other wild L. serriola accessions. When one or two copies of the Fol-4 and / or Fol-1 resistance QTL7.1 are present at a locus in the genome (i.e., heterozygous or homozygous), or when two copies of the Fol-4 and / or Fol-1 resistance QTL7.1 are present (i.e., homozygous), the plant line or plant variety is significantly more resistant to race Fol-4 and / or Fol-1 than a control or genetic control lacking QTL7.1. The absence of QTL7.1 on chromosome 7 of L. sativa is also referred to herein as "wild-type" (wt) genomic DNA of L. sativa present at the corresponding locus.

[0048] The genotypes of the SNP markers provided herein also indicate the absence of QTL7.1, or the presence of QTL7.1 in a homozygous or heterozygous form. For example, the genotype of SNP_07, which indicates QTL7.1, is "TC" or "TX," where X is A, G, or C (QTL7.1 / wt) or "TT" (QTL7.1 / QTL7.1), while the genotype indicating the wild type (i.e., cultivated lettuce) is "CC" (wt / wt) or XX, where X is A, G, or C. The genotype of SNP_06, which indicates QTL7.1, is "GT" or GX, where X is A, T, or C (QTL7.1 / wt) or "GG" (QTL7.1 / QTL7.1), while the genotype indicating the wild type (i.e., cultivated lettuce) is "TT" (wt / wt) or XX, where X is A, T, or C. Similarly, the SNP haplotype of the donor for SNP_06 and SNP_07 is "GT."

[0049] A genetic element, introgression fragment, or gene, or allele, or QTL that confers a trait (e.g., Fol-4 and / or Fol-1 resistance) is said to be "obtained from," or can be "obtained from," or can be "derived from," or can be "derived from," or can be "present in," or can be "found in," a plant, or plant part, or seed, or tissue, or cell, if it can be transferred using conventional breeding techniques from a plant or seed in which it is present to another plant or seed (e.g., a line or variety) in which it is not present, without altering the phenotype of the recipient plant other than the addition of the trait conferred by the genetic element, locus, introgression fragment, gene, or allele. These terms are used interchangeably, so that a genetic element, locus, introgression fragment, gene, or allele can be introduced into any other genetic background lacking the trait. Not only may the seeds that have been deposited and contain the genetic elements, loci, introgression fragments, genes, or alleles be used, but also the progeny / descendants from such seeds that have been selected to retain the genetic elements, loci, introgression fragments, genes, or alleles (e.g., commercial varieties developed from the deposited seeds or their progeny) may be used and are encompassed herein. Whether a plant (or the genomic DNA, cells, or tissues of the plant) contains the same genetic elements, loci, introgression fragments, genes, or alleles as are available from the deposited seeds may be determined by one of skill in the art using one or more techniques known in the art, such as phenotypic assays, whole genome sequencing, molecular marker analysis, trait mapping, chromosome painting, allele testing, and the like, or a combination of these techniques.

[0050] In the context of the present invention, "SNP (= single nucleotide polymorphism)" should be understood as a variation in a single nucleotide occurring at a specific position in the genome. A SNP is a variation of a single nucleotide at a given position in the genome between two plants. If a wild plant (donor plant) resistant to Fol-4 and / or Fol-1 exhibits a nucleotide at a specific single position in its corresponding sequence that differs from the corresponding nucleotide at the same position in a cultivated lettuce plant, this position defines an SNP between the wild donor and the cultivated lettuce. If the donor plant has one of four possible nucleotides (A, C, T, or G) at a specific position, an SNP occurs when the cultivated plant has one of the remaining three possible nucleotides at the same corresponding sequence position. Therefore, in cultivated lettuce plants containing a donor-derived introgression fragment, it can be easily determined whether the single nucleotide of the SNP is donor-derived or cultivated lettuce (recipient)-derived.

[0051] "SNP marker," as used herein, refers to a single nucleotide polymorphism in a genomic sequence that is linked to QTL7.1, whereby a particular nucleotide, also referred to as the donor SNP nucleotide (e.g., for SNP_07, the thymine at nucleotide 101 of SEQ ID NO:7, or the thymine at nucleotide 101 of a sequence comprising at least 95%, 96%, 97%, 98%, 99% sequence identity to SEQ ID NO:7), or a sequence comprising the particular nucleotide, is linked to the QTL. This nucleotide, or a sequence comprising this nucleotide, is also referred to as the "SNP genotype" or "SNP nucleotide" of the plant or plant part, and SNP_07 can be "T" (haploid on one chromosome) or "TT" (diploid on both chromosomes). Markers SNP_01 to SNP_10, especially SNP_02 to SNP_09 (which are located between or adjacent to SNP_01 and SNP_10), are linked to QTL7.1 and are located on the introgression fragment containing QTL7.1.

[0052] A "haplotype" or "haploid genotype" refers to the haploid genotype of several loci (particularly several SNP markers or several sequences containing SNP markers) in a plant. Thus, with respect to QTL7.1, a SNP haplotype can be the haploid genotype of at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 SNP markers (or sequences containing these SNP markers) among SNP_01 to SNP_10, or the haploid genotype of at least 2, 3, 4, 5, 6, 7, or 8 SNP_02 to SNP_09 (or sequences containing these SNP markers). For example, a plant containing QTL7.1 may contain a "G" for SNP_06 at nucleotide 101 of SEQ ID NO:6 (or nucleotide 101 of a sequence that is at least 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO:6), and a "T" for SNP_07 at nucleotide 101 of SEQ ID NO:7 (or nucleotide 101 of a sequence that is at least 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO:7), and It may contain a "T" for SNP_08 at nucleotide 101 of SEQ ID NO:8 (or nucleotide 101 of a sequence at least 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO:8), and therefore have the SNP haplotype GTT for SNPs_06 through SNP_08, which is the SNP haplotype of the L. serriola donor for SNPs_06 through SNP_08 (also referred to as the donor SNP haplotype). Diploid plants homozygous for QTL7.1 (and the introgression fragment containing QTL7.1) will have the SNP genotypes GG-TT-TT for SNPs_06 through SNP_08.

[0053] A "variant" or "orthologous" sequence, or "variant QTL7.1," refers to a QTL7.1 (or an introgression fragment containing this QTL) conferring Fol-4 and / or Fol-1 resistance from an L. serriola donor plant that differs from the QTL7.1 present in NCIMB44108. Such a variant QTL can be identified, for example, as having the same SNP haplotype as present in NCIMB44108 for at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 markers (preferably, consecutive markers) selected from SNP_01 to SNP_10 (preferably, SNP_02 to SNP_09). Thus, for example, a plant containing variant QTL7.1 may contain the SNP haplotype GGTT for SNP_05 through SNP_08, i.e., a "G" for SNP_05 at nucleotide 101 of SEQ ID NO:5 (or nucleotide 101 of a sequence that is at least 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO:5), and a "G" for SNP_05 at nucleotide 101 of SEQ ID NO:6 (or nucleotide 101 of a sequence that is at least 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO:6). It may include a "G" for SNP_06 at nucleotide 101 of SEQ ID NO:7 (or nucleotide 101 of a sequence that is at least 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO:7), a "T" for SNP_07 at nucleotide 101 of SEQ ID NO:8 (or nucleotide 101 of a sequence that is at least 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO:8), and a "T" for SNP_08 at nucleotide 101 of SEQ ID NO:8 (or nucleotide 101 of a sequence that is at least 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO:8). Additionally, variant QTL7.1 confers reduced susceptibility / increased resistance to Fol-4 and / or Fol-1 infection, as described herein.

[0054] In the context of the present invention, "resistance" or "resistant to" should be understood to mean a plant that is a host species of a particular pathogen and thus can be infected by a given pathogen, and that contains one or more genetic elements (e.g., one or more introgression fragments) that reduce the growth and / or spread of the pathogen in the plant after infection compared to a susceptible plant lacking such genetic elements. In the context of the present invention, "resistance" or "resistant to" refers in particular to plant cells or plants that are resistant to Fusarium oxysporum lactucae races Fol-4 and / or Fol-1, and in particular to plant cells or plants that are "highly resistant" (HR) to race Fol-4 and / or "intermediately resistant" (IR) to race Fol-1. Resistance is a relative term that can affect a range of (different) responses in plant cells or plants caused by pathogen infection. The effect of these responses by plant cells or plants can be measured by various means. Typically, this effect is measured by defining the symptom level exhibited on the plant part or plant. Typically, the average symptom (average disease score) of several (e.g., 5, 6, 7, 8, 9, 10, or more) plants of a line or genotype is compared with the average symptom (average disease score) of several plants of a control line or variety (preferably a susceptible control line or variety). Therefore, at least 5, 6, 7, 8, 9, 10, or more individual plants of a line or variety are scored at one or more time points after infection / inoculation, and an average disease score is calculated. In the context of the present invention, the following symptom levels (or disease scores) are applied according to phenotypic observations made after Fol-4 or Fol-1 infection using the CPVO protocol for immersion of seedling roots in the inoculum: 0: Plants without symptoms and healthy vessels 1: Plants with brown vessels only under the cotyledons, no yellowing or wilting 2: Plants with brown vessels above the cotyledons and no yellowing or wilting 3: Yellowing and wilting plants with brown vessels 4: Plant death.

[0055] See also Examples. An average disease score is calculated for each genotype.

[0056] In one aspect, the plant line or variety has an average disease score of 2.5 or less (e.g., 2.4, 2.3, 2.2, 2.1, 2.0, 1.9, 1.8, 1.7, 1.6, 1.5, 1.4, 1.3, 1.2, 1.1, 1.0, 0.9, 0.8, or 0.7 or less) for Fol-4, or 2.1 or less (e.g., 2.0, 1.9, 1.8, 1.7, 1.6, 1.5, 1.4, 1.3, 1.2, 1.1, 1.0, 0.9, 0.8, or 0.7 or less) for Fol-1. A susceptible control line or variety, such as Gisela for Fo-4 or Patriot for Fo-1, is said to contain "resistance" to infection by race Fol-4 or Fol-1 if it has the expected disease score when grown under the same conditions and infected in the same way (see also ISF Differential Sets). Resistance can be further subdivided into HR (highly resistant) and IR (intermediately resistant), although no such formal subdivision has been made for Fol-1. For Fol-4, the cultivars Lomeria and Palmos are HR, and Patriot, Rombella, Banchu Red Fire, and Ballerina are IR. Gisela and Costa Rica No. 4 are S (susceptible) to Fol-4. For Fol-1, only HR (Costa Rica No. 4, Rombella, and Palmos cultivars) or S (Gisela, Patriot, Banchu Red Fire, Ballerina, and Lomeria cultivars) are officially distinguished.

[0057] "Resistance to Fol-4 and / or Fol-1," or "increased (or enhanced) resistance to Fol-4 and / or Fol-1 infection," or "significantly increased (or enhanced) resistance to Fol-4 and / or Fol-1 infection," or "reduced susceptibility to Fol-4 and / or Fol-1 infection" refers to a cultivated lettuce plant, plant line, hybrid, or variety that contains QT17.1 (or a variant thereof) and that has a significantly lower mean disease score (on the 0-4 scale described above) at one or more measurement time points post-infection / inoculation (e.g., 18 dpi) (due to QTL7.1, particularly if homozygous) compared to a control plant (preferably a genetic control plant or recurrent parent) lacking this QTL. Preferably, the mean disease score of the line or variety is reduced by at least 1.0, 1.5, 2.0, or more points on a 0-4 scale. In the examples, recurrent parent plant lines lacking the QTL have an average disease score of 3.6 for Fol-1 or 3.1 for Fol-4, and introduction of QTL7 / 1 into the susceptible parent in a particular homozygous form reduces the average disease score, for example, to 2.1 or less for Fol-1 and to 0.9 or less for Fol-4.

[0058] "Dual resistance" herein refers to QTL7.1 (or a variant thereof) that confers resistance to both races Fol-4 and Fol-1, e.g., IR or HR to Fol-4 and IR or HR to Fol-1.

[0059] A "control plant" is a cultivated lettuce genotype, breeding line, or variety that lacks QTL7.1 (or a variant thereof), e.g., lacks the introgression fragment. The control plant is preferably of the same type as the plant containing the introgression fragment. For example, the original (e.g., susceptible) parent line (also called the recurrent parent) into which the QTL was introgressed is a suitable control. Other controls are, for example, known susceptible varieties, such as those from a differential set.

[0060] The term "marker assay" refers to a molecular marker assay that can be used to test whether an introgression from an L. serriola donor is present on chromosome 7 of cultivated lettuce, and whether this introgression fragment contains QTL7.1 (or a variant thereof), by determining the genotype or haplotype of any one or more markers linked to QTL7.1, for example by determining the genotype or haplotype of one or more SNP markers selected from SNP_01 to SNP_10 (in particular SNP_02 to SNP_09).

[0061] "Flanking markers" are markers located on either side of a region containing a QTL, i.e., the QTL is located in the chromosomal region between the flanking markers, for example, QTL7.1 (or variant QTL7.1) is located between flanking markers SNP_01 and SNP_10 (see Figure 4).

[0062] The SNP markers provided herein are located in a given order on the introgression fragment (see Figure 4). "Contiguous" markers refer to markers in the same consecutive order, so for example, two consecutive markers could be SNP_02 and SNP_03; SNP_03 and SNP_04, etc., and three consecutive markers could be SNP_03; SNP_02 and SNP_03, and SNP_04, etc.

[0063] "Average" or "mean" as used herein refers to the arithmetic mean, and both terms are used interchangeably. Thus, the term "average" or "mean" refers to the arithmetic mean of several measurements. Those skilled in the art understand that the phenotype of a plant line or plant variety depends to some extent on growing conditions, and therefore, the arithmetic mean of at least 5, 6, 7, 8, 9, 10, 15, 20, 30, 40, 50, or more plants (or plant parts) is measured, preferably in a randomized experimental design using several replicates and suitable control plants grown under the same conditions in the same experiment.

[0064] "Statistically significant" or "statistically significantly" different or "significantly" different refers to a characteristic of a plant line or variety that, when compared to a suitable control (e.g., a genetic control), exhibits a statistically significant difference in the characteristic from the (mean of the) control (e.g., using ANOVA, a p-value of less than 0.05, p<0.05).

[0065] A "recombinant chromosome" refers to a chromosome that has a new genetic makeup resulting from crossing over between homologous chromosomes (e.g., a "recombinant chromosome 7" (i.e., a chromosome 7 not present in either parent plant)) and that results from a rare double-crossover event between homologous chromosomes of a chromosome 7 pair. Provided herein, for example, is a recombinant L. sativa chromosome 7 containing an introgression fragment from an L. serriola donor.

[0066] The term "traditional breeding techniques" as used herein encompasses crossing, backcrossing, selfing, selection, doubled haploid production, embryo rescue, protoplast fusion, marker-assisted selection, mutation breeding, and the like, all of which are known to breeders (i.e., methods other than genetic modification / transformation / transgenic methods), by which, for example, recombinant chromosomes 1, 2, or 3 may be obtained, identified, and / or introduced.

[0067] "Backcrossing" refers to a breeding method that allows the transfer of a (single) trait, such as the Fol4 and / or Fol-1 resistance QTL7.1, from a (generally inferior) genetic background (e.g., L. serriola; also referred to as the "donor") to a (generally superior) genetic background (also referred to as the "recurrent parent") (e.g., L. sativa). The progeny of the cross (e.g., an F1 plant obtained by crossing the donor with cultivated lettuce; or an F2 or F3 plant obtained by selfing the F1) is "backcrossed" to a parent (e.g., cultivated lettuce) with a superior genetic background. After repeated backcrossing, the trait from the (generally inferior) genetic background will be incorporated into the (generally superior) genetic background.

[0068] "Marker-assisted selection" or "MAS" refers to the process of using the presence of molecular markers (e.g., SNP markers or INDEL markers) genetically linked to a specific locus or chromosomal region (e.g., the introgression fragment) to select plants for the presence of a specific locus or region (e.g., the introgression fragment). For example, a molecular marker physically linked to QTL7.1 (or a variant thereof) can be used to detect and / or select L. sativa plants containing the Fol-4 and / or Fol-1 resistance QTL7.1 (or a variant thereof) on chromosome 7, or to detect and / or select other L. serriola donors containing QTL7.1 or a variant thereof. The closer the linkage of a molecular marker to a locus, the less likely it is that this marker will dissociate from the locus through meiotic recombination. Similarly, the closer the linkage of two markers to each other, the less likely the two markers will segregate with each other (and the more likely they will co-segregate together).

[0069] "LOD score" (logarithm of odds (base 10)) refers to a statistical test often used in linkage analysis in animal and plant populations. The LOD score compares the likelihood of obtaining test data if two loci (molecular marker loci and / or phenotypic trait loci) are actually linked to the likelihood of observing the same data purely by chance. A positive LOD score supports the existence of linkage, and an LOD score above 3.0 is considered evidence of linkage. An LOD score of +3 indicates 1000 to 1 odds that the observed linkage did not occur by chance. In the example provided, QTL7.1 was mapped with an LOD of 8.75 relative to the peak marker.

[0070] "Vegetative propagation," "vegetative propagation," or "clonal propagation," are used interchangeably herein and refer to a method of taking a plant part and allowing it to form at least a root, where the plant part is defined as or obtained from (e.g., by cutting), for example, a leaf, pollen, embryo, cotyledon, hypocotyl, cell, protoplast, meristematic cell, root, root tip, stamen, anther, flower, shoot tip, shoot, stem, fruit, petiole, etc. When an entire plant is regenerated by vegetative propagation, this is also referred to as vegetative propagation.

[0071] "Cell culture" or "tissue culture" refers to the in vitro cultivation of plant cells or tissues.

[0072] An "isolated nucleic acid sequence" or "isolated DNA" refers to a nucleic acid sequence that is no longer present in the natural environment from which it has been isolated, e.g., a nucleic acid sequence in the nuclear or plastid genome of a bacterial host cell or a plant. Reference to a "sequence" herein is understood to refer to a molecule (e.g., a nucleic acid molecule) having such a sequence.

[0073] "Host cell," or "recombinant host cell," or "transformed cell" are terms that refer to a new individual cell (or organism) that results from the introduction of at least one nucleic acid molecule into said cell. The host cell is preferably a plant cell or a bacterial cell. The host cell may contain nucleic acids as extrachromosomal (episomal) replicating molecules, or the nucleic acids may be integrated into the host cell's nuclear or plastid genome, or as an introduced chromosome, (e.g., a minichromosome).

[0074] "Fine mapping" refers to a method that can more precisely (narrow) the location of a QTL and reduce the size of the introgression fragment containing the QTL. For example, near-isogenic lines (QTL-NILs) of a QTL can be created that contain various overlapping fragments of the introgression fragment within the uniform genetic background of the recurrent parent. Such lines can then be used to map which fragment the QTL is located on and identify lines with shorter introgression fragments containing the QTL.

[0075] A "genotyping" method or assay is a method that can determine the genotype or allelic composition of a plant, or plant part, or seed. Biallelic genotyping assays, such as the KASP assay, can distinguish between two alleles or genotypes at a genetic locus. Genotyping of SNP markers for one or more of SNP_01-SNP_10 (particularly one or more of SNP_02-SNP_09) is encompassed herein and can be used to detect and / or select plants, seeds, plant parts, or cells or tissues containing QTL7.1 or variants of QTL7.1, for example, in wild L. serriola or cultivated lettuce. For example, oligonucleotide primers can be generated for use in SNP genotyping assays, for example, for marker-assisted selection (MAS) of QTL7.1 or variants thereof.

[0076] An "oligonucleotide," or "oligo," or "oligonucleotide primer or probe" is a short, single-stranded polymer of nucleic acid, e.g., at least 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or more nucleotides in length. Depending on their intended use, oligos can be unmodified or modified with various chemistries, such as the addition of 5' or 3' phosphate groups to enable ligation or block extension, respectively; labeling with radionucleotides or fluorophores and / or quenchers for use as probes; incorporation of thiol, amino, or other reactive moieties to enable covalent attachment of functional molecules such as enzymes; and extension with other linkers and spacers of various functionalities. DNA oligos are most commonly used, but RNA oligos are also available. The length of an oligo is usually designated by adding the suffix -mer. For example, an oligonucleotide having 19 nucleotides (bases) is called a 19-mer. In most applications, oligonucleotides are designed to base pair with DNA or RNA strands. The most common use of oligonucleotides is as primers for PCR (polymerase chain reaction). Primers are designed so that at least a portion of their sequence is complementary to the target sequence for amplification. The optimal primer length for a complementary sequence is, for example, 18 to 22 nucleotides. Optimal primer sequences for PCR are usually determined using primer design software.

[0077] A "DNA microarray" is an array with many microscopic spots of DNA (usually oligonucleotides) attached to a solid support. The assay target can be DNA, cDNA, or cRNA. Depending on the system, hybridization of the target to a specific spot is detected by fluorescence, chemiluminescence, or colloidal silver or gold. Microarrays are used in multiple applications, such as simultaneous measurement of the expression of many genes, allowing genome-wide gene expression analysis, and genotyping studies using, for example, single nucleotide polymorphism (SNP) or InDel analysis.

[0078] "Complementary strand" refers to the two strands of complementary sequences, which in the context of double-stranded DNA may be referred to as the sense strand (or plus strand) and the antisense strand (or minus strand). The sense / plus strand is generally the transcribed sequence of DNA (or the mRNA produced during transcription), while the antisense / minus strand is the strand complementary to the sense sequence. For any of the sequences provided herein, only one strand of the sequence is shown, but the complementary strand of a given strand is also encompassed herein. Complementary nucleotides in DNA are A, which is complementary to T, and G, which is complementary to C. Complementary nucleotides in RNA are A, which is complementary to U, and G, which is complementary to C.

[0079] Detailed Description In the research that led to this invention, a wide range of wild lettuce accessions were screened for resistance to various races of Fusarium wilt, including races Fol-4 and Fol-1. One wild L. serriola accession was found that exhibited resistance to both of these races. Surprisingly, when resistance was mapped, only a single QTL was found, located on chromosome 7 of the lettuce reference genome. This QTL was therefore designated QTL7.1.

[0080] QTL7.1 from the L. serriola donor was crossed with a Fol-1 and Fol-4 susceptible L. sativa cultivar (recurrent parent) to generate L. sativa lines containing QTL7.1 from the L. serriola donor. In initial disease testing, the L. sativa lines showed high resistance to Fol-4 but lower resistance to Fol-1 compared to the L. serriola donor line. While not limiting the present invention, the genetic background of the recurrent parent may influence the expression of Fol-1 resistance.

[0081] In one aspect of the present invention, there is provided a lettuce plant (Lactuca sativa L.) comprising QTL7.1 (or a variant thereof) from L. serriola, wherein QTL7.1 (or a variant thereof) confers high resistance to Fusarium race Fol-4 and, further, moderate and / or high resistance to race Fol-1.

[0082] Thus, one aspect of the present invention provides a lettuce plant (Lactuca sativa L.) containing QTL7.1 (or a variant of QTL7.1) from L. serriola, where QTL7.1 (or a variant thereof) confers resistance to Fusarium race Fol-4 and resistance to race Fol-1. Such dual resistance conferred by a single QTL is particularly advantageous in breeding, as only a single QTL needs to be present rather than two separate QTLs. This simplifies breeding, for example, by marker-assisted breeding, and also allows for stacking of QTL7.1 (or a variant QTL7.1) with other genes at separate loci (e.g., other Fol-1 resistance genes).

[0083] An L. sativa line containing QTL7.1 from an L. serriola donor has been deposited under the Budapest Treaty by Nunhems BV (Napoleonsweg 152, 6083 AB Nunhem, The Netherlands) and has been assigned accession number NCIMB44108. Thus, in one aspect, QTL7.1 is present in, obtainable from, or obtained from the seeds deposited under NCIMB44108. QTL7.1 (and the introgression fragment containing this QTL7.1) is present in the deposited seeds in a homozygous form.

[0084] This QTL has an "additive" effect, meaning that the effect of the homozygous QTL on Fusarium wilt resistance is the combined effect of the heterozygous QTL. Thus, in one embodiment, this QTL7.1 is preferably present in a homozygous form in L. sativa plants to confer the highest level of resistance. However, this QTL may also be present in a heterozygous form in one embodiment.

[0085] The QTL of the present invention, or an introgression fragment containing this QTL, can be obtained from the genome of a wild-type Lactuca serriola line containing QTL7.1 (or a variant thereof) that confers resistance to Fusarium wilt, for example, but not limited to, from the genome of an L. serriola plant available from the CGN collection or the US ARS-GRIN collection. QTL7.1 of the present invention can be obtained, for example, from a resistant L. serriola line used as a donor for introgressing QTL7.1 into L. sativa (representative seeds have been deposited under NCIMB44108).

[0086] Thus, the present invention relates to cultivated lettuce plants comprising a QTL or comprising an introgression fragment from L. serriola comprising a QTL conferring Fol-1 and / or Fol-4 resistance, said QTL being located on chromosome 7 of the L. sativa genome in the region between nucleotides 64.382.881 and 69.375.685 of chromosome 7 of the reference genome for lettuce (which is genome V11) found on the World Wide Web at ncbi.nlm.nih.gov / data-hub / genome / ?taxon=4236.

[0087] The resistance-conferring QTL7.1, or a variant from, for example, another L. serriola line, is located on the L. serriola introgression fragment and is located between the adjacent markers SNP_01 and SNP_10. Therefore, the physical location of the QTL on chromosome 7 is between the nucleotides (or bases) for SNP_01 and SNP_10 on chromosome 7 of L. sativa.

[0088] Since SNP_01 corresponds to nucleotide 64.382.881 on chromosome 7 of the L. sativa V11 reference genome and SNP_10 corresponds to nucleotide 69.375.685 on chromosome 7 of the L. sativa V11 reference genome, the present QTL7.1 (or a variant thereof, or an introgression fragment containing QTL7.1 or a variant) is located between nucleotides 64.382.881 and 69.375.685 on chromosome 7 of the L. sativa V11 reference genome. It is not important which nucleotide (A, T, C, or G) is actually present at the SNP_01 and SNP_10 positions on chromosome 7.

[0089] A total of 10 SNP markers (single nucleotide polymorphism markers) are provided herein that are linked to or "indicate" (or "indicate" an introgression fragment containing) QTL7.1 (or a variant thereof), and one or more of these SNP markers can be used to identify plants, seeds, and plant parts containing QTL7.1 (or a variant). These 10 SNP markers are designated SNP_01 through SNP_10, with SNP_07 being the peak marker in QTL mapping, and SNP_01 and SNP_10 being "flanking" markers on either side of the region containing QTL7.1 (or a variant) from the L. serriola donor. See also Figure 4. Thus, the flanking markers SNP_01 and SNP_10 define the region on chromosome 7 where QTL7.1 (or a variant QTL7.1) is found.

[0090] The SNP markers are "single nucleotide polymorphisms" that have either the L. serriola donor nucleotide or a different nucleotide (e.g., a repetitive parent nucleotide). For all 10 SNP markers, the right and left sequences flanking the SNP marker (i.e., the polymorphic nucleotide) are provided herein from the wild L. serriola donor (SEQ ID NO: 11-SEQ ID NO: 20) and the L. sativa reference genome V11 (SEQ ID NO: 11-SEQ ID NO: 20). The sequences are provided as consensus sequences for both the wild L. serriola donor and the L. sativa reference genome (SEQ ID NOs: 1-10), taking into account nucleotide differences in the genomic DNA sequence adjacent to the SNP nucleotide between the wild L. serriola donor and the L. sativa reference genome (SEQ ID NOs: 1-10). For example, nucleotide 67 in SEQ ID NO: 11 is a "C," but in SEQ ID NO: 21 it is an "A," such that the consensus sequence for SEQ ID NO: 1 has an "M" (indicating a C or A) at nucleotide 67.

[0091] In one aspect, provided are cultivated lettuce (L. sativa) plants, seeds, plant parts, cells, and / or tissues comprising an introgression fragment from a wild L. serriola donor, wherein the introgression fragment comprises QTL7.1 (or a variant thereof), which is physically located in the region of chromosome 7 starting at nucleotide 64.382.881 (corresponding to SNP_01 at nucleotide 101 of SEQ ID NO: 1, 11, or 21) and ending at nucleotide 69.375.685 (corresponding to SNP_10 at nucleotide 101 of SEQ ID NO: 10, 20, or 30), relative to chromosome 7 of the V11 reference genome.

[0092] In one aspect, the introgression fragment comprising QTL7.1 (or variant QTL7.1) comprises L. serriola donor nucleotides for at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 SNP markers selected from SNP_01 to SNP_10, and in particular comprises L. serriola donor nucleotides for at least 1, 2, 3, 4, 5, 6, 7, or 8 SNP markers selected from SNP_02 to SNP_09, i.e. SNP_02 at nucleotide 101 of SEQ ID NO:2 or at the equivalent position in a sequence that comprises at least 95% sequence identity to SEQ ID NO:2, SNP_03 at nucleotide 101 of SEQ ID NO:3 or at the equivalent position in a sequence that comprises at least 95% sequence identity to SEQ ID NO:3, SNP_04 at nucleotide 101 of SEQ ID NO:4 or at the equivalent position in a sequence that comprises at least 95% sequence identity to SEQ ID NO:4, SNP_05 at nucleotide 101 of SEQ ID NO:5 or at the equivalent position in a sequence that comprises at least 95% sequence identity to SEQ ID NO:5, SNP_06 at nucleotide 101 of SEQ ID NO:6 or at the equivalent position in a sequence that comprises at least 95% sequence identity to SEQ ID NO:6 SNP_06 at an equivalent position in a sequence with at least 95% sequence identity to SEQ ID NO:7, SNP_07 at nucleotide 101 of SEQ ID NO:7 or at an equivalent position in a sequence with at least 95% sequence identity to SEQ ID NO:7, SNP_08 at nucleotide 101 of SEQ ID NO:8 or at an equivalent position in a sequence with at least 95% sequence identity to SEQ ID NO:8, SNP_09 at nucleotide 101 of SEQ ID NO:9 or at an equivalent position in a sequence with at least 95% sequence identity to SEQ ID NO:9.

[0093] In one aspect, the at least 1, 2, 3, 4, 5, 6, 7, or 8 markers include at least the following SNP markers: an L. serriola donor nucleotide for SNP_07 at nucleotide 101 of SEQ ID NO:7 or at an equivalent position in a sequence comprising at least 95% sequence identity to SEQ ID NO:7.

[0094] In another embodiment, the at least 1, 2, 3, 4, 5, 6, 7, or 8 markers include L. serriola donor nucleotides for at least one or more of the following SNP markers: SNP_07 at nucleotide 101 of SEQ ID NO:7 or at an equivalent position in a sequence with at least 95% sequence identity to SEQ ID NO:7, SNP_06 at nucleotide 101 of SEQ ID NO:6 or at an equivalent position in a sequence with at least 95% sequence identity to SEQ ID NO:6, and / or SNP_08 at nucleotide 101 of SEQ ID NO:8 or at an equivalent position in a sequence with at least 95% sequence identity to SEQ ID NO:8.

[0095] In another embodiment, the at least one, two, three, four, five, six, seven, or eight markers include L. serriola donor nucleotides for at least one or more of the following SNP markers: SNP_07 at nucleotide 101 of SEQ ID NO:7 or at an equivalent position in a sequence comprising at least 95% sequence identity to SEQ ID NO:7; SNP_05 at nucleotide 101 of SEQ ID NO:5 or at an equivalent position in a sequence comprising at least 95% sequence identity to SEQ ID NO:5; SNP_06 at nucleotide 101 of SEQ ID NO:6 or at an equivalent position in a sequence comprising at least 95% sequence identity to SEQ ID NO:6; SNP_08 at nucleotide 101 of SEQ ID NO:8 or at an equivalent position in a sequence comprising at least 95% sequence identity to SEQ ID NO:8; and / or SNP_09 at nucleotide 101 of SEQ ID NO:9 or at an equivalent position in a sequence comprising at least 95% sequence identity to SEQ ID NO:9.

[0096] In one aspect, there is provided a cultivated Lactuca sativa plant comprising an introgression fragment from a wild L. serriola donor comprising homozygous or heterozygous QTL7.1 (or a variant thereof), the introgression fragment comprising: - a quantitative trait locus (QTL7.1 or variant) located between the single nucleotide polymorphism marker SNP_01 at nucleotide 101 of SEQ ID NO: 1 (or a variant of SEQ ID NO: 1) and the single nucleotide polymorphism marker SNP_10 at nucleotide 101 of SEQ ID NO: 10 (or a variant of SEQ ID NO: 10), which QTL confers resistance to Fusarium oxysporum lactucae specialis (Fol) race 1 (Fol-1) and / or race 4 (Fol-4) when homozygous or heterozygous. Includes.

[0097] In one aspect, QTL7.1 (or a variant thereof, or an introgression fragment comprising this QTL) is present in a heterozygous form in cultivated Lactuca sativa plants, cells, or tissues.

[0098] In another aspect, QTL7.1 (or a variant thereof, or an introgression fragment containing this QTL) is present in a homozygous form in a Lactuca sativa plant, seed, plant part, cell, or tissue.

[0099] In one aspect, the L. serriola donor for the QTL is selected from L. serriola donors that contain identical SNP haplotypes for at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 SNP markers for the QTL present in seed deposited under the Budapest Treaty on February 1, 2023 by Nunhems BV and identified as NCIMB44108. Thus, in one aspect, seeds deposited in NCIMB44108 or progeny of seeds (containing QTL7.1) may be used as the donor for QTL7.1, or any other L. serriola donor that exhibits resistance to Fol-1 and / or Fol-4 may be used, which wild L. serriola donor has the same SNP haplotypes for at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 SNP markers described herein for the QTL present in NCIMB44108 that may be used as the donor for QTL7.1 or variant QTL7.1.

[0100] Thus, the present invention relates to cultivated Lactuca sativa plants that contain a Fol-4 and / or Fol-1 resistance-conferring QTL introgressed from a Fol-4 and / or Fol-1 resistant L. serriola line (particularly a double-resistant L. serriola line), whereby increased resistance is conferred by an introgression fragment (comprising GTL7.1 or a variant thereof) on chromosome 7 of cultivated lettuce, the introgression fragment being derived from an L. serriola line referred to as the "donor" of the QTL.

[0101] As used herein, when reference is made to an introgression fragment on chromosome 7 carrying a Fol-4 and / or Fol-1 resistance conferring QTL, this encompasses introgression fragments of various sizes, for example the fragment found in NCIMB 44108 that contains all of the SNP markers that contain the donor SNP nucleotides or are linked to the QTL (SNP_01 to SNP_10, or SNP_02 to SNP_09, or any markers in between), but also smaller introgression fragments (fewer than 10 or 8 of these SNP markers, for example only 2, 3, 4, 5, 6, 7, 8, or 9 of the SNP markers), which however remain large enough to confer Fol-4 and / or Fol-1 resistance (compared to a control or genetic control) when the introgression fragment is present in heterozygous, and preferably homozygous, form in the cultivated lettuce genome. In other words, this fragment carries QTL7.1 or a variant thereof, i.e. still confers significantly enhanced Fol-4 and / or Fol-1 resistance (compared to a control, such as a genetic control) when the introgression fragment is present in heterozygous, and preferably homozygous, form in the cultivated lettuce genome.

[0102] Furthermore, when referring to an introgression fragment on chromosome 7 having a Fol-4 and / or Fol-1 resistance-conferring QTL, this includes, for example, introgression fragments derived from various donors containing QTL7.1 or variant QTL7.1 present in NCIMB 44108. Such variant QTL7.1 has the same SNP haplotype (or SNP genotype) for at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 of the SNP markers described in Table 1, and the at least 2, 3, 4, 5, 6, 7, or 8 markers are preferably selected from SNP_02 to SNP_09. For example, L. serriola donors available in the US ARS-GRIN collection (see the World Wide Web at npgsweb.ars-grin.gov / gringglobal / search), or L. serriola donors available at the Center for Genetic Resources, Wageningen University, http: / / cgngenis.wur.nl / (CGN), or other lines containing the same SNP haplotypes or genotypes for at least 2, 3, 4, 5, 6, 7, 8, 9, or all 10 markers. Preferably, donors containing the same SNP haplotypes or genotypes for at least 2, 3, 4, 5, 6, 7, 8, 9, or all 10 markers also have Fol-4 and / or Fol-1 resistance, e.g., HF or IR resistance to Fol-4 and / or HF or IR resistance to Fol-1. This can be tested as described in the Examples. Various donors may, for example, be initially selected based on their resistance phenotype and then screened for the presence of QTL7.1 (or a variant thereof) using one, more or all of SNP_01 to SNP_10, or SNP_02 to SNP_09, or vice versa, first screened for the presence of QTL7.1 (or a variant thereof) and then tested for the Fol-4 and / or Fol-1 resistance phenotype.

[0103] "SNP_01", in the context of the present invention, should be understood as a SNP at position 101 of SEQ ID NO: 1 or at an equivalent position in a sequence comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO: 1 (e.g., SEQ ID NO: 11 (comprising SNP_01 at nucleotide 101 of SEQ ID NO: 11) or SEQ ID NO: 21 (comprising SNP_01 at nucleotide 101 of SEQ ID NO: 21)). The location of SNP_01 on chromosome 7 (of the V11 reference genome of lettuce) is shown in Tables 1, 2, and 3. As SNP_01 is a SNP marker adjacent to the genomic region comprising QTL7.1 (or a variant thereof), the SNP_01 nucleotide may, in one embodiment, be derived from either an L. serriola donor or an L. sativa plant. Therefore, the SNP_01 nucleotide can be either an adenine (indicating a resistant L. serriola donor) or a guanine, thymine, or cytosine (indicating an L. sativa genome).

[0104] "SNP_02" in the context of the present invention should be understood as the SNP at position 101 of SEQ ID NO:2 or at the equivalent position in a sequence comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:2 (e.g., SEQ ID NO:12 (comprising SNP_02 at nucleotide 101 of SEQ ID NO:12) or SEQ ID NO:22 (comprising SNP_02 at nucleotide 101 of SEQ ID NO:22)). The location of SNP_02 on chromosome 7 (of the V11 reference genome of lettuce) is found in Tables 1, 2, and 3. The SNP_02 nucleotide, in one embodiment, is from an L. serriola donor, i.e., is a guanine (indicative of a resistant L. serriola donor).

[0105] "SNP_03" in the context of the present invention should be understood as the SNP at position 101 of SEQ ID NO: 3 or at the equivalent position in a sequence comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO: 3 (e.g., SEQ ID NO: 13 (comprising SNP_03 at nucleotide 101 of SEQ ID NO: 13) or SEQ ID NO: 23 (comprising SNP_03 at nucleotide 101 of SEQ ID NO: 23)). The location of SNP_03 on chromosome 7 (of the V11 reference genome of lettuce) can be found in Tables 1, 2, and 3. The SNP_03 nucleotide, in one embodiment, is from an L. serriola donor, i.e., is a cytosine (indicative of a resistant L. serriola donor).

[0106] "SNP_04" in the context of the present invention should be understood as the SNP at position 101 of SEQ ID NO:4 or at the equivalent position in a sequence comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:4 (e.g., SEQ ID NO:14 (comprising SNP_04 at nucleotide 101 of SEQ ID NO:14) or SEQ ID NO:24 (comprising SNP_04 at nucleotide 101 of SEQ ID NO:24)). The location of SNP_04 on chromosome 7 (of the V11 reference genome of lettuce) is found in Tables 1, 2, and 3. The SNP_04 nucleotide, in one embodiment, is from an L. serriola donor, i.e., is an adenine (indicative of a resistant L. serriola donor).

[0107] "SNP_05" in the context of the present invention should be understood as the SNP at position 101 of SEQ ID NO:5 or at the equivalent position in a sequence comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:5 (e.g., SEQ ID NO:15 (comprising SNP_05 at nucleotide 101 of SEQ ID NO:15) or SEQ ID NO:25 (comprising SNP_05 at nucleotide 101 of SEQ ID NO:25)). The location of SNP_05 on chromosome 7 (of the V11 reference genome of lettuce) can be found in Tables 1, 2, and 3. The SNP_05 nucleotide, in one embodiment, is from an L. serriola donor, i.e., is a guanine (indicative of a resistant L. serriola donor).

[0108] "SNP_06" in the context of the present invention should be understood as the SNP at position 101 of SEQ ID NO:6 or at the equivalent position in a sequence comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:6 (e.g., SEQ ID NO:16 (comprising SNP_06 at nucleotide 101 of SEQ ID NO:16) or SEQ ID NO:26 (comprising SNP_06 at nucleotide 101 of SEQ ID NO:26)). The location of SNP_06 on chromosome 7 (of the V11 reference genome of lettuce) is found in Tables 1, 2, and 3. The SNP_06 nucleotide, in one embodiment, is from an L. serriola donor, i.e., is a guanine (indicative of a resistant L. serriola donor).

[0109] "SNP_07" in the context of the present invention should be understood as the SNP at position 101 of SEQ ID NO:7 or at the equivalent position in a sequence comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:7 (e.g., SEQ ID NO:17 (comprising SNP_07 at nucleotide 101 of SEQ ID NO:17) or SEQ ID NO:27 (comprising SNP_07 at nucleotide 101 of SEQ ID NO:27)). The location of SNP_07 on chromosome 7 (of the V11 reference genome of lettuce) can be found in Tables 1, 2, and 3. The SNP_07 nucleotide, in one embodiment, is from an L. serriola donor, i.e., thymine (indicating a resistant L. serriola donor).

[0110] "SNP_08" in the context of the present invention should be understood as the SNP at position 101 of SEQ ID NO:8 or at the equivalent position in a sequence comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:8 (e.g., SEQ ID NO:18 (comprising SNP_08 at nucleotide 101 of SEQ ID NO:18) or SEQ ID NO:28 (comprising SNP_08 at nucleotide 101 of SEQ ID NO:28)). The location of SNP_08 on chromosome 7 (of the V11 reference genome of lettuce) is found in Tables 1, 2, and 3. The SNP_08 nucleotide, in one embodiment, is from an L. serriola donor, i.e., thymine (indicating a resistant L. serriola donor).

[0111] "SNP_09" in the context of the present invention should be understood as the SNP at position 101 of SEQ ID NO:9 or at the equivalent position in a sequence comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:9 (e.g., SEQ ID NO:19 (comprising SNP_09 at nucleotide 101 of SEQ ID NO:19) or SEQ ID NO:29 (comprising SNP_09 at nucleotide 101 of SEQ ID NO:29)). The location of SNP_09 on chromosome 7 (of the V11 reference genome of lettuce) is found in Tables 1, 2, and 3. The SNP_09 nucleotide, in one embodiment, is from an L. serriola donor, i.e., is an adenine (indicative of a resistant L. serriola donor).

[0112] "SNP_10", in the context of the present invention, should be understood to be the SNP at position 101 of SEQ ID NO: 10 or at the equivalent position in a sequence comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO: 10 (e.g., SEQ ID NO: 20 (comprising SNP_10 at nucleotide 101 of SEQ ID NO: 20) or SEQ ID NO: 30 (comprising SNP_10 at nucleotide 101 of SEQ ID NO: 30)). The location of SNP_10 on chromosome 7 (of the lettuce V11 reference genome) is found in Tables 1, 2, and 3. As SNP_10 is a SNP marker adjacent to the genomic region comprising QTL7.1 (or a variant thereof), the SNP_10 nucleotide may, in one aspect, be derived from either an L. serriola donor or an L. sativa plant. Therefore, the SNP_10 nucleotide can be either guanine (indicating the resistant L. serriola donor) or adenine, thymine, or cytosine (indicating the L. sativa genome).

[0113] Thus, when a SNP nucleotide at nucleotide 101 of a particular SEQ ID NO is referred to herein, it encompasses a SNP nucleotide at an equivalent position in a sequence that has at least 95%, 96%, 97%, 98%, 99% sequence identity to that SEQ ID NO (which sequences are referred to herein as "variant sequences" of that particular SEQ ID NO, or alternatively as sequences that have "substantial sequence identity" to that SEQ ID NO). Pairwise sequence alignments can be used, for example, to determine whether a nucleotide is present at an equivalent position in such sequences.

[0114] QTL7.1 and its variants on chromosome 7 Thus, in one aspect, there is provided a cultivated L. sativa plant comprising an introgression fragment from a wild L. serriola donor, wherein the introgression fragment comprises QTL7.1 or a variant thereof, and wherein the introgression fragment comprises all or a portion of the region beginning at nucleotide (or base) 64382881 on chromosome 7 (corresponding to SNP_01) and ending at nucleotide (or base) 69375685 on chromosome 7 (corresponding to SNP_10). In other words, all or a portion of the region beginning at nucleotide 64382881 on chromosome 7 (SNP_01) and ending at nucleotide 69375685 on chromosome 7 (SNP_10) is, in one aspect, from a wild L. serriola donor and comprises QTL7.1 or a variant thereof. In particular, this region includes the L. serriola donor nucleotides for one, more than one, or all of SNP_02 through SNP_09. The subregion between SNP_01 and SNP_10 that contains QTL7.1 (or a variant) can be identified, for example, by fine-mapping. The peak marker for QTL7.1 is SNP_07. Therefore, if QTL7.1 (or a variant) is known to be located between SNP_05 and SNP_09, a plant of the present invention need only include the introgression region beginning at nucleotide 66347850 on chromosome 7 (SNP_05) and ending at nucleotide 69331664 on chromosome 7 (SNP_09).

[0115] In one aspect, QTL7.1 (or a variant thereof) is located between marker SNP_01 at nucleotide 101 of SEQ ID NO: 1 (or nucleotide 101 in a variant sequence of SEQ ID NO: 1) and marker SNP_10 at nucleotide 101 of SEQ ID NO: 10 (or nucleotide 101 in a variant sequence of SEQ ID NO: 10).

[0116] In another aspect, QTL7.1 (or a variant thereof) is located between marker SNP_02 at nucleotide 101 of SEQ ID NO:2 (or nucleotide 101 in a variant sequence of SEQ ID NO:2) and marker SNP_09 at nucleotide 101 of SEQ ID NO:09 (or nucleotide 101 in a variant sequence of SEQ ID NO:9).

[0117] In a further aspect, QTL7.1 (or a variant thereof) is located between marker SNP_03 at nucleotide 101 of SEQ ID NO:3 (or nucleotide 101 in the variant sequence of SEQ ID NO:3) and marker SNP_09 at nucleotide 101 of SEQ ID NO:09 (or nucleotide 101 in the variant sequence of SEQ ID NO:9). In a further aspect, QTL7.1 (or a variant thereof) is located between marker SNP_04 at nucleotide 101 of SEQ ID NO:4 (or nucleotide 101 in the variant sequence of SEQ ID NO:4) and marker SNP_09 at nucleotide 101 of SEQ ID NO:09 (or nucleotide 101 in the variant sequence of SEQ ID NO:9). In yet another aspect, QTL7.1 (or a variant thereof) is located between marker SNP_05 at nucleotide 101 of SEQ ID NO:5 (or nucleotide 101 in the variant sequence of SEQ ID NO:5) and marker SNP_09 at nucleotide 101 of SEQ ID NO:09 (or nucleotide 101 in the variant sequence of SEQ ID NO:9). In yet another aspect, QTL7.1 (or a variant thereof) is located between marker SNP_06 at nucleotide 101 of SEQ ID NO: 6 (or nucleotide 101 in a variant sequence of SEQ ID NO: 6) and marker SNP_08 at nucleotide 101 of SEQ ID NO: 08 (or nucleotide 101 in a variant sequence of SEQ ID NO: 8).

[0118] In one aspect, the introgression fragment of the invention (comprising QTL7.1 or a variant thereof) is a fragment comprising this QTL or a variant thereof and a smaller fragment (portion) (e.g., having a size of 4.5 Mb, 4.0 Mb, 3.5 Mb, 3.0 Mb, 2.5 Mb, 2.0 Mb, 1.5 Mb, 1.0 Mb, 0.5 Mb, 100 kb, 50 kb, 35 kb, 30 kb, 20 kb, or smaller) of the region starting at nucleotide (or base) 64442022 (SNP_02 position) on chromosome 7 and ending at nucleotide (or base) 69331664 (SNP_09 position) on chromosome 7. In one aspect, the portion is at least 5 kb, 10 kb, 20 kb, or larger in size.

[0119] In one aspect, an introgression fragment on chromosome 7 comprising QTL7.1 or a variant thereof can be obtained by crossing a plant grown from NCIMB44108 with another lettuce plant (particularly a cultivated lettuce plant).

[0120] In one aspect, a cultivated lettuce plant of the invention comprising QTL7.1 or a variant thereof is a plant, wherein the introgression fragment on chromosome 7 is obtained by crossing a plant grown from seeds deposited under accession number NCIMB44108 with another lettuce plant. Thus, in one aspect, the QTL is a QTL present in seeds deposited under accession number NCIMB44108.

[0121] In a further aspect, a cultivated lettuce plant of the invention comprising QTL7.1 or a variant thereof is a plant obtained by crossing the introgression fragment on chromosome 7 with another lettuce plant (particularly an elite breeding line) that comprises the same donor SNP haplotype (or donor genotype) for at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 SNP markers linked to this QTL (i.e., SNP_01 to SNP_10, or SNP_02 to SNP_09 for QTL7.1 as shown in Table 1). Thus, in one aspect, the QTL is a variant QTL that is present in a wild L. serriola donor line that comprises the same donor SNP haplotype (or donor genotype) for at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 SNP markers that are present in, for example, NCIMB44108. Preferably, the donor also contains a resistance phenotype to the Fol-4 and / or Fol-1 races, preferably double resistance.

[0122] When referring to SNP markers herein that indicate the presence of an introgression fragment (and the Fol-4 and / or Fol-1 resistance QTL present on this introgression fragment), it is understood that reference is being made to the donor SNP genotype or haplotype that indicates this introgression fragment (i.e., the donor SNP genotypes or haplotypes shown, for example, in Tables 1-3). Note that SNP marker genotypes can distinguish between introgression fragments that are homozygous or heterozygous. In homozygous cases, the SNP nucleotides are identical, while in heterozygous cases, the nucleotides are not identical. The SNP genotype of a "wild-type" chromosome lacking the introgression fragment is the other haplotype (e.g., the haplotype of the recurrent parent). Thus, for example, the genotype of SNP_07, which represents an introgression fragment containing QTL7.1, is "TC" (QTL7.1 / wt) or "TT" (QTL7.1 / QTL7.1), whereas the SNP genotype representing the wild type / genetic control (lacking this introgression fragment) is, for example, "CC" (wt / wt). This can also be written as the genotype "TX" (QTL7.1 / wt) or "TT" (QTL7.1 / QTL7.1), whereas the SNP genotype representing the wild type / genetic control (lacking this introgression fragment) is, for example, "XX" (wt / wt). X can be any nucleotide (A, T, C, or G), and in particular any other nucleotide (e.g., A, C, or G) other than the donor nucleotide. Therefore, when referring to a plant or plant part (e.g., cell) that contains a homozygous or heterozygous introgression fragment, it is understood that the SNP markers linked to the introgression fragment have the corresponding SNP genotype or haplotype.

[0123] Thus, in one aspect, there is provided a cultivated L. sativa plant comprising, in a homozygous or heterozygous form, an introgression fragment on chromosome 7, which confers Fol-4 and / or Fol-1 resistance compared to a lettuce plant lacking the introgression fragment on chromosome 7 (e.g., a genetic control or control variety) when grown under identical conditions.

[0124] Thus, the plants of the present invention comprise a cultivated lettuce genome having at least one (heterozygous) or two (homozygous) recombinant chromosomes 7. The recombinant chromosomes contain fragments of an L. serriola donor that are readily distinguishable from the cultivated L. sativa genome by molecular marker analysis (e.g., analysis of one or more of SNP_01 to SNP_10, and in particular analysis of one or more of SNP_02 to SNP_09), whole genome sequencing, chromosome painting, and similar techniques.

[0125] In one embodiment, the introgression fragment on chromosome 7 is derived from an L. serriola donor and comprises QTL7.1 or a variant thereof, and includes all or a portion of the region starting from nucleotide SNP_01 and ending with SNP_10, and in particular all or a portion of the region starting from SNP_02 and ending with SNP_09. Thus, the introgression fragment comprises QTL7.1 or a variant thereof and one, or more, or all (e.g., 2, 3, 4, 5, 6, 7, 8, 9, or 10) SNP markers from the donor, e.g., selected from SNP_01 to SNP_10 or selected from SNP_02 to SNP_09 as shown in Table 1.

[0126] In one aspect, the introgression fragment comprises QTL7.1 (or a variant) and one, more, or all of SEQ ID NO:1 to SEQ ID NO:10 or SEQ ID NO:2 to SEQ ID NO:9, or a sequence variant thereof comprising at least 95% sequence identity to any one of these sequences (e.g., one, more, or all of SEQ ID NO:11 to SEQ ID NO:20 or SEQ ID NO:12 to SEQ ID NO:19, or one, more, or all of SEQ ID NO:21 to SEQ ID NO:30 or SEQ ID NO:22 to SEQ ID NO:29).

[0127] In one aspect, the presence of an introgression fragment on chromosome 7 comprising QTL7.1 (or a variant) in the genome of (or in DNA extracted from) a plant, seed, plant part, or plant cell or plant tissue is detectable by a molecular marker assay (e.g., a genotyping assay) which detects one or more markers of the introgression fragment, in particular at least 2, 3, 4, 5, 6, 7, 8, 9, 10 or more donor SNP haplotypes (or genotypes) of SNP_01 to SNP_10 at nucleotide 101 of SEQ ID NOs: 1 to 10 (or at nucleotide 101 of variant sequences thereof), respectively, and in particular at least 2, 3, 4, 5, 6, 7 or 8 markers of SNP_02 to SNP_09. However, as mentioned, other techniques may be used, for example, the SNP genotype of a marker may also be determined by sequencing or by using surrogate markers located between the SNP markers provided herein.

[0128] In one aspect, the presence of an introgression fragment on chromosome 7 comprising QTL7.1 (or a variant) in the genome of (or in DNA extracted from) a plant, seed, plant part, or plant cell or plant tissue can be detected by detecting the presence of one, more, or all of SEQ ID NOs: 1-10 or 2-9, one, more, or all of SEQ ID NOs: 11-20 or 12-19, or one, more, or all of SEQ ID NOs: 21-30 or 22-29.

[0129] When reference is made herein to one or more molecular markers or sequences being "detectable," for example, by a molecular marker assay, this naturally means that the plant or plant part contains the one or more markers or sequences in its genome; otherwise, the markers or sequences would not be detectable.

[0130] Lettuce plants containing an introgression fragment (QTL7.1) on chromosome 7

[0010] In one aspect, there is provided a cultivated L. sativa plant comprising, in a homozygous or heterozygous form, an introgression fragment on chromosome 7 from an L. serriola donor, wherein the introgression fragment comprises a quantitative trait locus (QTL) located between a single nucleotide polymorphism marker SNP_01 at nucleotide 101 of SEQ ID NO:1 (or at nucleotide 101 of a variant of SEQ ID NO:1 that comprises at least 95% sequence identity to SEQ ID NO:1) and a single nucleotide polymorphism marker SNP_10 at nucleotide 101 of SEQ ID NO:10 (or at nucleotide 101 of a variant of SEQ ID NO:10 that comprises at least 95% sequence identity to SEQ ID NO:1), wherein the QTL confers Fol-4 and / or Fol-1 resistance. In one embodiment, this QTL is located on chromosome 7 between bases 64382881 (SNP_01) and 69375685 (SNP_10).

[0131] Thus, in one aspect, QTL7.1 (or a variant thereof) is located in the region between SNP_01 in SEQ ID NO: 1 (or a variant thereof) and SNP_10 in SEQ ID NO: 10 (or a variant thereof).

[0132] Provided, in one aspect, is a Lactuca sativa plant comprising an introgression fragment from Lactuca serriola on chromosome 7, the introgression fragment comprising a quantitative trait locus (QTL) that confers resistance to Fusarium oxysporum lactucae race Fol-4 and / or Fol-1, wherein the introgression fragment on chromosome 7 comprises QTL7.1 in a region beginning at nucleotide 64442022 and ending at nucleotide 69331664 of chromosome 7; The introgression fragment contains the following markers: a) the GX or GG genotype of single nucleotide polymorphism marker SNP_02 at nucleotide 101 of SEQ ID NO:2 (or nucleotide 101 in a variant of SEQ ID NO:2 that contains at least 95% sequence identity to SEQ ID NO:2); b) the CX or CC genotype of single nucleotide polymorphism marker SNP_03 at nucleotide 101 of SEQ ID NO: 3 (or nucleotide 101 in a variant of SEQ ID NO: 3 that contains at least 95% sequence identity to SEQ ID NO: 3); c) the AX or AA genotype of single nucleotide polymorphism marker SNP_04 at nucleotide 101 of SEQ ID NO: 4 (or nucleotide 101 in a variant of SEQ ID NO: 4 that contains at least 95% sequence identity to SEQ ID NO: 4); d) the GX or GG genotype of single nucleotide polymorphism marker SNP_05 at nucleotide 101 of SEQ ID NO: 5 (or nucleotide 101 in a variant of SEQ ID NO: 5 that contains at least 95% sequence identity to SEQ ID NO: 5); e) the GX or GG genotype of single nucleotide polymorphism marker SNP_06 at nucleotide 101 of SEQ ID NO: 6 (or nucleotide 101 in a variant of SEQ ID NO: 6 that contains at least 95% sequence identity to SEQ ID NO: 6); f) the TX or TT genotype of single nucleotide polymorphism marker SNP_07 at nucleotide 101 of SEQ ID NO: 7 (or nucleotide 101 in a variant of SEQ ID NO: 7 that contains at least 95% sequence identity to SEQ ID NO: 7); g) the TX or TT genotype of single nucleotide polymorphism marker SNP_08 at nucleotide 101 of SEQ ID NO:8 (or nucleotide 101 in a variant of SEQ ID NO:8 that contains at least 95% sequence identity to SEQ ID NO:8); h) the AX or AA genotype of single nucleotide polymorphism marker SNP_09 at nucleotide 101 of SEQ ID NO: 9 (or nucleotide 101 in a variant of SEQ ID NO: 9 that contains at least 95% sequence identity to SEQ ID NO: 9). The plant is a Lactuca sativa plant containing at least 1, 2, 3, 4, 5, 6, 7, or 8 species of Lactuca sativa.

[0133] Thus, in one aspect, there is provided an L. sativa plant comprising, in a homozygous or heterozygous form, an introgression fragment on chromosome 7, said introgression fragment conferring Fol-4 and / or Fol-1 resistance (compared to a plant lacking said introgression fragment (e.g., a recurrent parent or control)), and said introgression fragment comprising: a) the GX or GG genotype of single nucleotide polymorphism marker SNP_02 at nucleotide 101 of SEQ ID NO:2 (or nucleotide 101 in a variant of SEQ ID NO:2 that contains at least 95% sequence identity to SEQ ID NO:2); b) the CX or CC genotype of single nucleotide polymorphism marker SNP_03 at nucleotide 101 of SEQ ID NO: 3 (or nucleotide 101 in a variant of SEQ ID NO: 3 that contains at least 95% sequence identity to SEQ ID NO: 3); c) the AX or AA genotype of single nucleotide polymorphism marker SNP_04 at nucleotide 101 of SEQ ID NO: 4 (or nucleotide 101 in a variant of SEQ ID NO: 4 that contains at least 95% sequence identity to SEQ ID NO: 4); d) the GX or GG genotype of single nucleotide polymorphism marker SNP_05 at nucleotide 101 of SEQ ID NO: 5 (or nucleotide 101 in a variant of SEQ ID NO: 5 that contains at least 95% sequence identity to SEQ ID NO: 5); e) the GX or GG genotype of single nucleotide polymorphism marker SNP_06 at nucleotide 101 of SEQ ID NO: 6 (or nucleotide 101 in a variant of SEQ ID NO: 6 that contains at least 95% sequence identity to SEQ ID NO: 6); f) the TX or TT genotype of single nucleotide polymorphism marker SNP_07 at nucleotide 101 of SEQ ID NO: 7 (or nucleotide 101 in a variant of SEQ ID NO: 7 that contains at least 95% sequence identity to SEQ ID NO: 7); g) the TX or TT genotype of single nucleotide polymorphism marker SNP_08 at nucleotide 101 of SEQ ID NO:8 (or nucleotide 101 in a variant of SEQ ID NO:8 that contains at least 95% sequence identity to SEQ ID NO:8); h) the AX or AA genotype of single nucleotide polymorphism marker SNP_09 at nucleotide 101 of SEQ ID NO: 9 (or nucleotide 101 in a variant of SEQ ID NO: 9 that contains at least 95% sequence identity to SEQ ID NO: 9). In one embodiment, an L. sativa plant is provided, comprising a SNP marker haplotype or genotype of at least 1, 2, 3, 4, 5, 6, 7, or 8 SNP markers selected from the group consisting of:

[0134] In another aspect, an L. sativa plant comprises, in a homozygous or heterozygous form, an introgression fragment on chromosome 7, wherein the introgression fragment confers Fol-4 and / or Fol-1 resistance (compared to a plant lacking the introgression fragment (e.g., a recurrent parent or control)), and wherein the introgression fragment is a) the AX or AA genotype of single nucleotide polymorphism marker SNP_01 at nucleotide 101 of SEQ ID NO: 1 (or nucleotide 101 in a variant of SEQ ID NO: 1 that contains at least 95% sequence identity to SEQ ID NO: 1); b) the GX or GG genotype of single nucleotide polymorphism marker SNP_02 at nucleotide 101 of SEQ ID NO:2 (or nucleotide 101 in a variant of SEQ ID NO:2 that contains at least 95% sequence identity to SEQ ID NO:2); c) the CX or CC genotype of single nucleotide polymorphism marker SNP_03 at nucleotide 101 of SEQ ID NO: 3 (or nucleotide 101 in a variant of SEQ ID NO: 3 that contains at least 95% sequence identity to SEQ ID NO: 3); d) the AX or AA genotype of single nucleotide polymorphism marker SNP_04 at nucleotide 101 of SEQ ID NO: 4 (or nucleotide 101 in a variant of SEQ ID NO: 4 that contains at least 95% sequence identity to SEQ ID NO: 4); e) the GX or GG genotype of single nucleotide polymorphism marker SNP_05 at nucleotide 101 of SEQ ID NO: 5 (or nucleotide 101 in a variant of SEQ ID NO: 5 that contains at least 95% sequence identity to SEQ ID NO: 5); f) the GX or GG genotype of single nucleotide polymorphism marker SNP_06 at nucleotide 101 of SEQ ID NO: 6 (or nucleotide 101 in a variant of SEQ ID NO: 6 that contains at least 95% sequence identity to SEQ ID NO: 6); g) the TX or TT genotype of single nucleotide polymorphism marker SNP_07 at nucleotide 101 of SEQ ID NO: 7 (or nucleotide 101 in a variant of SEQ ID NO: 7 that contains at least 95% sequence identity to SEQ ID NO: 7); h) the TX or TT genotype of single nucleotide polymorphism marker SNP_08 at nucleotide 101 of SEQ ID NO:8 (or nucleotide 101 in a variant of SEQ ID NO:8 that contains at least 95% sequence identity to SEQ ID NO:8); i) the AX or AA genotype of single nucleotide polymorphism marker SNP_09 at nucleotide 101 of SEQ ID NO: 9 (or nucleotide 101 in a variant of SEQ ID NO: 9 that contains at least 95% sequence identity to SEQ ID NO: 9); j) the GX or GG genotype of single nucleotide polymorphism marker SNP_10 at nucleotide 101 of SEQ ID NO: 10 (or nucleotide 101 in a variant of SEQ ID NO: 10 that contains at least 95% sequence identity to SEQ ID NO: 10). In one embodiment, an L. sativa plant is provided, comprising a SNP marker haplotype or genotype of at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 SNP markers selected from the group consisting of:

[0135] When referring to a SNP in a variant sequence, the variant sequence contains at least 95%, 96%, 97%, 98%, or 99% sequence identity to the referenced sequence. X refers to any nucleotide in the sequence on chromosome 7 of the other chromosome of the pair. In one aspect, X can be a recurrent parent nucleotide described in Tables 1, 2, and 3. In another aspect, X is a nucleotide that differs from the L. serriola donor nucleotide described in Tables 1, 2, and 3.

[0136] In one embodiment, the at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 markers are consecutive markers.

[0137] In one aspect, the present introgression fragment comprises donor SNP marker haplotypes or genotypes for at least SNP_06, SNP_07, and SNP_08, as SNP_07 was mapped to be the peak marker for QTL7.1 (or variant).

[0138] Thus, the fragment containing QTL7.1 (or a variant) may be large (comprising donor nucleotides for SNP_01 through SNP_10 or SNP_02 through SNP_09) or may be smaller and may lack markers with the genotype or haplotype of the L. serriola donor (e.g., markers with the L. sativa genotype or haplotype instead; see also Table 1), but may still confer Fol-4 and / or Fol-1 resistance to L. sativa plants, i.e., may still contain QTL7.1 or may still contain a variant of QTL7.1. Such smaller introgression fragments are one embodiment of the present invention. Plants with smaller introgression fragments (i.e., containing the resistance-conferring QTL7.1 or variant) that still confer Fol-4 and / or Fol-1 resistance may be generated using known techniques, such as fine mapping or similar techniques. For example, by starting with a plant containing the introgression fragment found in the seed deposited under accession number NCIMB44108, crossing such a plant with another L. sativa plant, and selfing and / or backcrossing the progeny of the cross to generate a population of plants that may include recombinants with a smaller introgression fragment on chromosome 7, which fragment still confers Fol-4 and / or Fol-1 resistance compared to a plant lacking the introgression fragment (e.g., a control), for example, compared to a fragment comprising donor nucleotides for markers SNP_03 to SNP_09, or SNP_04 to SNP_09, or SNP_05 to SNP_09, or SNP_05 to SNP_08, or SNP_6 to SNP_09, or SNP_06 to SNP_08.

[0139] The size of the smaller introgression fragment can be determined using a marker assay. One or more of the SNP markers with the donor genotype or haplotype may be missing. The L. sativa genotype or haplotype is then detected for these SNP markers. The Fol-4 and / or Fol-1 resistance of plants containing such smaller introgression fragments can then be compared in the disease assay described herein, i.e., multiple plants containing the smaller introgression fragment are grown in an experiment together with suitable control plants lacking the introgression fragment.

[0140] Alternatively, the same QTL or variant QTL (QTL7.1 or variant QTL7.1) may be introgressed from a different L. serriola donor line, which may optionally lack all of the SNP markers disclosed herein, i.e., the SNP haplotype of this donor line may only be identical to the SNP haplotype of QTL7.1 present in seed of NCIMB44108 with respect to, for example, 2, 3, 4, 5, 6, 7, or 8 of the SNPs. The SNP markers provided herein may be used to identify such alternative donor sources by screening L. serriola germplasm (i.e., lines) using marker assays to detect genotypes or haplotypes at one or more of markers SNP_01-SNP_10, or, for example, markers SNP_02-SNP_09, SNP_03-SNP_09, SNP_05-SNP_09, or SNP_06-SNP_09, or SNP_06-SNP_08, or even only smaller subgroups of these markers. Thus, plants containing the same QTL7.1 or variant QTL7.1 from other L. serriola lines are also an embodiment of the present invention. Thus, as long as at least 2, 3, 4, 5, 6, or 7, 8, 9, or 10 of the donor SNP nucleotides SNP_01 through SNP_10, or the SNPs SNP_02 through SNP_09, SNP_03 through SNP_09, SNP_05 through SNP_09, or SNP_06 through SNP_09, or SNP_06 through SNP_08, are present, the donor may contain QTL7.1 (or a variant thereof) and is encompassed herein. One skilled in the art could then introgress this QTL7.1 (or a variant thereof) into L. sativa to enhance Fol-4 and / or Fol-1 tolerance as described herein and to confirm that the QTL enhances Fol-4 and / or Fol-1 tolerance when present in L. sativa.Prior to gene transfer, wild donors may also be tested for Fol-4 and / or Fol-1 resistance in the assays described, e.g., donors containing at least IR or HR resistance to Fol-4 and / or Fol-1 may be selected.

[0141] As noted above, in one embodiment, the L. sativa plants of the present invention comprise an introgression fragment comprising at least a subset of SNP markers (i.e., at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 markers of SNP_01 to SNP_10, or at least 2, 3, or 4, 5, 6, 7, or 8 markers of SNP_01 to SNP_10, or SNP_02 to SNP_09, SNP_03 to SNP_09, SNP_05 to SNP_09, or SNP_06 to SNP_09, or SNP_06 to SNP_08) along with the genotype (or haplotype) of an L. serriola donor. In one aspect, the cultivated lettuce plant comprises all of SNP_01 to SNP_10, or all but one or two markers, or all but one or two markers of SNP_02 to SNP_09. In particular, one or more markers next to the flanking markers (e.g., SNP_02, or SNP_02 and SNP_03, or SNP_09, or SNP_09 and SNP_08) may be absent.

[0142] Therefore, the introgression fragment (and the L. sativa plant or plant part, e.g., cell, containing the introgression fragment) may be detected in a marker assay by detecting the SNP genotype or haplotype of one, more, or all (preferably at least 2, 3, 4, 5, 6, 7, 8, 9, or 10) of the above markers in the introgression fragment (i.e., of the donor genome fragment).

[0143] Thus, in one aspect, a quantitative trait locus (QTL7.1 or a variant thereof) has been found to be present on chromosome 7 of a wild L. serriola donor that, when introduced (introgressed) into an L. sativa variety or breeding line and when present in heterozygous or homozygous form, confers Fol-4 and / or Fol-1 resistance (preferably double resistance) to cultivated lettuce plants. This QTL, or the introgression fragment containing this QTL, is additive, i.e., it is sufficient for the introgression fragment to be present on one of the chromosomes 7 (one recombinant chromosome 7), and the counterpart homologous chromosome 7 can be the (non-recombinant) chromosome 7 of L. sativa that lacks this introgression fragment.

[0144] L. serriola lines can be obtained, for example, from the USDA National Plant Germplasm System collection or other seed collection, and can therefore be screened for the presence of QTL7.1 (or variants), for example, using the marker assays described herein, and lines containing 2, 3, 4, 5, 6, 7, 8, or more of the SNP markers indicative of QTL7.1 (or variants) can be crossed with L. sativa plants having normal, wild-type, non-recombinant chromosome 7. The F1 or F2 generation (or further generations, such as the F3 or backcross generation) can then be screened for recombinant plants having the introgression fragment or portion thereof carrying the QTL using the molecular marker assays described herein.

[0145] In one embodiment, the introgression fragment comprising QTL7.1 (or a variant) is identifiable by (and therefore includes) one or more of the markers described elsewhere herein, and in particular by (and therefore includes) the donor nucleotides for one or more of markers SNP_01 to SNP_10 or SNP_02 to SNP_09 of the introgression fragment on chromosome 7, or a subset of markers. In one aspect, the invention provides L. sativa having a cultivated (domesticated) lettuce genome comprising Fol-4 and / or Fol-1 resistance, wherein the resistance is conferred by an introgression fragment on chromosome 7 of the lettuce, and wherein the introgression fragment or the QTL is obtained (or is obtainable) by crossing a plant grown from seed deposited in NCIMB 44108, or a progeny of this plant (which comprises one or more markers disclosed herein that are linked to the QTL), with another lettuce plant. Thus, in one aspect, the L. sativa plants of the invention comprise the same introgression fragment and the same recombinant chromosome 7 as present in NCIMB 44108 (which comprises all of the wild donor haplotypes for SNP markers SNP_01 to SNP_10, or SNP_01 to SNP_09, or comprises SEQ ID NOs: 1 to 10, or SEQ ID NOs: 2 to 9, or SEQ ID NOs: 11 to 20, or SEQ ID NOs: 12 to 19), or a shorter fragment of this introgression fragment, whereby this shorter fragment carries the genetic element (QTL7.1) that confers resistance.

[0146] Therefore, in one aspect, the present invention relates to a plant of the invention, i.e. a cultivated L. sativa plant comprising, in homozygous or heterozygous form, an introgression fragment comprising QTL7.1 from an L. serriola plant on chromosome 7, wherein said introgression fragment is the introgression fragment "similar to" / "identical to" / "identical to" the seed deposited under number NCIMB44108, or a shorter fragment (partial fragment) thereof, which still confers Fol-4 and / or Fol-1 resistance due to the presence of QTL7.1 on this partial fragment.

[0147] Similarly, in one aspect, the present invention relates to a plant of the invention, i.e. a cultivated L. sativa plant comprising, in a homozygous or heterozygous form, an introgression fragment comprising QTL7.1 on chromosome 7 from an L. serriola plant, said QTL being a QTL "similar to" / "identical to" / "identical to" in seed deposited under number NCIMB44108, and which confers Fol-4 and / or Fol-1 resistance due to the presence of QTL7.1.

[0148] Because SEQ ID NOs: 11-20 are derived from the wild donor used to generate NCIMB44108, one or more of these sequences, particularly one or more of SEQ ID NOs: 12-19 (or sequences comprising at least 95%, 96%, 97%, 98% sequence identity to any one of SEQ ID NOs: 11-20), can be used to identify the introgression fragment or subfragment of a particular donor, since the entire sequence (SNP nucleotides, and flanking sequences) is derived from the donor line used in the Examples.

[0149] However, one or more of the consensus sequences of Table 1 (SEQ ID NO: 1 to SEQ ID NO: 10, in particular SEQ ID NO: 2 to SEQ ID NO: 9, or sequences comprising at least 95%, 96%, 97%, 98% sequence identity to any one of these sequences), or the sequences of Table 3, may also be used, since the donor ANP nucleotides of all of these sequences are specific to L. serriola, and the donor SNP nucleotides of SNP_02 to SNP_06 and SNP_08 to SNP_09 are specific to the donor strains used in the examples.

[0150] In one embodiment, the present invention relates to a plant of the present invention, i.e., a cultivated Lactuca sativa plant, comprising, in a homozygous or heterozygous form, an introgression fragment on chromosome 7 containing QTL7.1 (or a variant) from an L. serriola donor, wherein the introgression fragment is the same introgression fragment as in the seed deposited under NCIMB 44108, or a variant of the introgression fragment of this seed, i.e., containing QTL7.1 (or a variant), but the genomic sequence may be different. Due to genetic differences between wild accessions, the genomic sequence of an introgression fragment containing QTL7.1 (or a variant) from another Fol-4 and / or Fol-1 resistant L. serriola accession is likely not 100% identical to the genomic sequence when introgressed into NCIMB 44108, but may be, for example, at least 95%, 96%, 97%, or 98% identical to this sequence. This difference can be seen in that certain SNP markers linked to QTL7.1 (or variants thereof) may be commonly found in various lines, while other SNP markers may only be found in specific lines. Thus, for example, not all of SNP_2 through SNP_09 are found in other L. serriola donors, and a SNP donor haplotype may include two, three, four, five, six, seven, eight, or nine of donor SNP markers SNP_1 through SNP_10 or SNP_02 through SNP_09. For example, another Fol-4 and / or Fol-1 resistant L. serriola donor may have slightly different donor SNPs for SNP_01 through SNP_10 or SNP_02 through SNP_09, e.g., one, two, or three SNPs differ by donor nucleotide.

[0151] However, QTL7.1 (or variants of QTL7.1) may still be present in such wild accessions. One skilled in the art can identify and introgress QTL7.1 (or variants) that contain the region (delimited by the SNP_01 and SNP_10 flanking markers) found in other L. serriola donors into cultivated lettuce, for example, by detecting wild accessions that contain the SNP markers or a subset thereof, introducing these SNP markers (or a subset) into a cultivated lettuce line or variety, and assessing the Fol-4 and / or Fol-1 resistance of this line or variety in comparison to a line or variety lacking the SNP markers (or a subset) (i.e., lacking the introgression fragment).

[0152] Even if the SNP haplotypes for SNP_01-SNP_10 or SNP_02-SNP_09 are identical to the SNP haplotypes for QTL7.1 found in seeds of NCIMB44108, the actual nucleotide sequences flanking the SNP nucleotides may differ in other donors and therefore in the consensus sequence that accounts for variation between the donor and the L. sativa reference genome. Therefore, the other donor may contain the same donor SNP nucleotide at nucleotide 101, but for example, in a sequence that has at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NOs: 1-10 (or SEQ ID NOs: 2-9) when aligned pairwise, or in a sequence that has at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NOs: 11-20 (or SEQ ID NOs: 12-19) when aligned pairwise, or in a sequence that has at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NOs: 21-30 (or SEQ ID NOs: 22-29) when aligned pairwise.

[0153] In one embodiment, the presence of an introgression fragment comprising QTL7.1, or a chromosome 7 region comprising QTL7.1 (or a variant or orthologous chromosome 7 region) is determined by: a) the AX or AA genotype of single nucleotide polymorphism marker SNP_01 at nucleotide 101 of SEQ ID NO: 1, or SEQ ID NO: 11, or SEQ ID NO: 21 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO: 1, or SEQ ID NO: 11, or SEQ ID NO: 21); (This marker is optional, as it is a flanking marker that bounds the QTL-containing region on one side.) b) the GX or GG genotype of single nucleotide polymorphism marker SNP_02 at nucleotide 101 of SEQ ID NO:2, or SEQ ID NO:12, or SEQ ID NO:22 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:2, or SEQ ID NO:12, or SEQ ID NO:22); c) the CX or CC genotype of single nucleotide polymorphism marker SNP_03 at nucleotide 101 of SEQ ID NO:3, or SEQ ID NO:13, or SEQ ID NO:23 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:3, or SEQ ID NO:13, or SEQ ID NO:23); d) the AX or AA genotype of single nucleotide polymorphism marker SNP_04 at nucleotide 101 of SEQ ID NO:4, or SEQ ID NO:14, or SEQ ID NO:24 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:4, or SEQ ID NO:14, or SEQ ID NO:24); e) the GX or GG genotype of single nucleotide polymorphism marker SNP_05 at nucleotide 101 of SEQ ID NO:5, or SEQ ID NO:15, or SEQ ID NO:25 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:5, or SEQ ID NO:15, or SEQ ID NO:25); f) the GX or GG genotype of single nucleotide polymorphism marker SNP_06 at nucleotide 101 of SEQ ID NO:6, or SEQ ID NO:16, or SEQ ID NO:26 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:6, or SEQ ID NO:16, or SEQ ID NO:26); g) the TX or TT genotype of single nucleotide polymorphism marker SNP_07 at nucleotide 101 of SEQ ID NO:7, or SEQ ID NO:17, or SEQ ID NO:27 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:7, or SEQ ID NO:17, or SEQ ID NO:27); h) the TX or TT genotype of single nucleotide polymorphism marker SNP_08 at nucleotide 101 of SEQ ID NO:8, or SEQ ID NO:18, or SEQ ID NO:28 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:8, or SEQ ID NO:18, or SEQ ID NO:28); i) the AX or AA genotype of single nucleotide polymorphism marker SNP_09 at nucleotide 101 of SEQ ID NO:9, or SEQ ID NO:19, or SEQ ID NO:29 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:9, or SEQ ID NO:19, or SEQ ID NO:29); j) the GX or GG genotype of single nucleotide polymorphism marker SNP_10 at nucleotide 101 of SEQ ID NO: 10, or SEQ ID NO: 20, or SEQ ID NO: 30 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO: 10, or SEQ ID NO: 20, or SEQ ID NO: 30); (This marker is optional, as it is a flanking marker that delimits the QTL-containing region on the other side.) The gene is detectable by a molecular marker assay (and a genome comprising one or more molecular markers) that detects at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 single nucleotide polymorphism (SNP) markers selected from the group consisting of:

[0154] Thus, in one embodiment, the presence of an introgression fragment comprising QTL7.1 (or a variant), or a chromosome 7 region (or a variant chromosome 7 region) comprising QTL7.1 (or a variant), can be determined by: a) the GX or GG genotype of single nucleotide polymorphism marker SNP_02 at nucleotide 101 of SEQ ID NO:2, or SEQ ID NO:12, or SEQ ID NO:22 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:2, or SEQ ID NO:12, or SEQ ID NO:22); b) the CX or CC genotype of single nucleotide polymorphism marker SNP_03 at nucleotide 101 of SEQ ID NO:3, or SEQ ID NO:13, or SEQ ID NO:23 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:3, or SEQ ID NO:13, or SEQ ID NO:23); c) the AX or AA genotype of single nucleotide polymorphism marker SNP_04 at nucleotide 101 of SEQ ID NO:4, or SEQ ID NO:14, or SEQ ID NO:24 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:4, or SEQ ID NO:14, or SEQ ID NO:24); d) the GX or GG genotype of single nucleotide polymorphism marker SNP_05 at nucleotide 101 of SEQ ID NO:5, or SEQ ID NO:15, or SEQ ID NO:25 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:5, or SEQ ID NO:15, or SEQ ID NO:25); e) the GX or GG genotype of single nucleotide polymorphism marker SNP_06 at nucleotide 101 of SEQ ID NO:6, or SEQ ID NO:16, or SEQ ID NO:26 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:6, or SEQ ID NO:16, or SEQ ID NO:26); f) the TX or TT genotype of single nucleotide polymorphism marker SNP_07 at nucleotide 101 of SEQ ID NO:7, or SEQ ID NO:17, or SEQ ID NO:27 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:7, or SEQ ID NO:17, or SEQ ID NO:27); g) the TX or TT genotype of single nucleotide polymorphism marker SNP_08 at nucleotide 101 of SEQ ID NO:8, or SEQ ID NO:18, or SEQ ID NO:28 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:8, or SEQ ID NO:18, or SEQ ID NO:28); h) the AX or AA genotype of single nucleotide polymorphism marker SNP_09 at nucleotide 101 of SEQ ID NO: 9, or SEQ ID NO: 19, or SEQ ID NO: 29 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO: 9, or SEQ ID NO: 19, or SEQ ID NO: 29). The gene is detectable by a molecular marker assay (and a genome comprising one or more molecular markers) that detects at least 1, 2, 3, 4, 5, 6, 7, or 8 single nucleotide polymorphism (SNP) markers selected from the group consisting of:

[0155] In one embodiment, the at least one, two, three, four, or more markers detected are consecutive markers.

[0156] In one embodiment, at least SNP_07 is detected (i.e., present in the genome) in addition to one or more markers, particularly in addition to one or more markers contiguous to SNP_07 (e.g., SNP_06 and / or SNP_08, or SNP_05 and SNP_06 and / or SNP_08, or SNP_08 and / or SNP_09). Thus, in one embodiment, SNP_07 is present / detected, and in addition, one or more contiguous markers selected from upstream and / or downstream of SNP_07 (e.g., SNP_2 to SNP_06 upstream of SNP_07 and SNP_08 and SNP_09 downstream) are present / detected (see also FIG. 4).

[0157] Therefore, in one embodiment, the lettuce plant, seed or tissue of the present invention comprises: - optionally, an adenine (A) at nucleotide 101 (designated SNP_01) of SEQ ID NO: 1, or SEQ ID NO: 11, or SEQ ID NO: 21, or at the equivalent nucleotide of a genomic sequence that contains substantial sequence identity to SEQ ID NO: 1, 11, or 21 (i.e., an AA or AX genotype) (in other words, an adenine is present at the physical position on chromosome 7 shown in Table 1); and / or - at least a guanine (G) (i.e., GG or GX genotype) at nucleotide 101 (designated SNP_02) of SEQ ID NO: 2, or SEQ ID NO: 12, or SEQ ID NO: 22, or at the equivalent nucleotide of a genomic sequence that contains substantial sequence identity to SEQ ID NO: 2, 12, or 22 (i.e., a guanine is present at the physical position on chromosome 7 shown in Table 1); and / or - at least a cytosine (C) at nucleotide 101 (designated SNP_03) of SEQ ID NO: 3, or SEQ ID NO: 13, or SEQ ID NO: 23, or at the equivalent nucleotide of a genomic sequence that contains substantial sequence identity to SEQ ID NO: 3, 13, or 23 (i.e., CC or CX genotype) (in other words, a cytosine is present at the physical position on chromosome 7 shown in Table 1); and / or - at least an adenine (A) at nucleotide 101 (designated SNP_04) of SEQ ID NO: 4, or SEQ ID NO: 14, or SEQ ID NO: 24, or at the equivalent nucleotide of a genomic sequence that contains substantial sequence identity to SEQ ID NO: 4, 14, or 24 (i.e., AA or AX genotype) (in other words, an adenine is present at the physical position on chromosome 7 shown in Table 1); and / or - at least a guanine (G) (i.e., GG or GX genotype) at nucleotide 101 (designated SNP_05) of SEQ ID NO: 5, or SEQ ID NO: 15, or SEQ ID NO: 25, or at the equivalent nucleotide of a genomic sequence that contains substantial sequence identity to SEQ ID NO: 5, 15, or 25 (in other words, a guanine is present at the physical position on chromosome 7 shown in Table 1); and / or - at least a guanine (G) (i.e., GG or GX genotype) at nucleotide 101 (designated SNP_06) of SEQ ID NO: 6, or SEQ ID NO: 16, or SEQ ID NO: 26, or at the equivalent nucleotide of a genomic sequence that contains substantial sequence identity to SEQ ID NO: 6, 16, or 26 (i.e., a guanine is present at the physical position on chromosome 7 shown in Table 1); and / or - at least a thymine (T) (i.e., TT or TX genotype) at nucleotide 101 (designated SNP_07) of SEQ ID NO: 7, or SEQ ID NO: 17, or SEQ ID NO: 27, or at the equivalent nucleotide of a genomic sequence that contains substantial sequence identity to SEQ ID NO: 7, 17, or 27 (i.e., a thymine is present at the physical position on chromosome 7 shown in Table 1); and / or - at least a thymine (T) (i.e., TT or TX genotype) at nucleotide 101 (designated SNP_08) of SEQ ID NO: 8, or SEQ ID NO: 18, or SEQ ID NO: 28, or at the equivalent nucleotide of a genomic sequence that contains substantial sequence identity to SEQ ID NO: 8, 18, or 28 (i.e., a thymine is present at the physical position on chromosome 7 shown in Table 1); and / or - at least an adenine (A) at nucleotide 101 (designated SNP_09) of SEQ ID NO: 9, or SEQ ID NO: 19, or SEQ ID NO: 29, or at the equivalent nucleotide of a genomic sequence that contains substantial sequence identity to SEQ ID NO: 9, 19, or 29 (i.e., AA or AX genotype) (in other words, an adenine is present at the physical position on chromosome 7 shown in Table 1); and / or - optionally a guanine (A) at nucleotide 101 (referred to as SNP_10) of SEQ ID NO: 10, or SEQ ID NO: 20, or SEQ ID NO: 30, or at the equivalent nucleotide of a genomic sequence that contains substantial sequence identity to SEQ ID NO: 10, 20, or 30 (i.e., a GG or GX genotype) (in other words, a guanine is present at the physical position on chromosome 7 shown in Table 1); Includes.

[0158] In a further embodiment, the presence of an introgression fragment or chromosome 7 region (or a variant or orthologous chromosome 7 region) comprising QTL7.1 is detectable by a molecular marker assay detecting at least three, four, or five single nucleotide polymorphism (SNP) markers from the subgroup consisting of: SNP_06 to SNP_08; SNP_04 to SNP_08; SNP_05 to SNP_08, SNP_04 to SNP_09, SNP_04 to SNP_08, SNP_03 to SNP_09, SNP_03 to SNP_08, SNP_02 to SNP_09, SNP_02 to SNP_08, SNP_05 to SNP_07, or SNP_07 to SNP_09.

[0159] A SNP genotype refers to two nucleotides and the genomic sequence that includes one of those two nucleotides (one on each chromosome 7). Thus, a plant with a TT genotype for SNP_07 has the same nucleotide (T) on both chromosomes (i.e., is homozygous), whereas a plant with a TX genotype for SNP_07 has one chromosome that has a T at nucleotide 101 of SEQ ID NO: 1, 11, or 21 (or the equivalent nucleotide in a genomic sequence that contains substantial sequence identity to SEQ ID NO: 1, 11, or 21) and one chromosome that has an X at nucleotide 101 of SEQ ID NO: 1, 11, or 21 (or the equivalent nucleotide in a genomic sequence that contains substantial sequence identity to SEQ ID NO: 1, 11, or 21), and is heterozygous, whereby X can be any nucleotide. It is clear that the genomic sequences surrounding the SNP markers provided herein may vary slightly in introgression fragments from other donors (i.e., variants or orthologous chromosome 7 regions), and therefore the nucleotide sequences before and after the SNP may not be 100% identical to the sequences provided herein. Thus, sequences that have substantial sequence identity (i.e., at least 95% identity) with the sequences provided herein but contain the identical SNP nucleotide at the SNP position are encompassed herein.

[0160] In one aspect, an introgression fragment containing QTL7.1 (or a variant) detectable by one or more of the markers described above, or a region on chromosome 7 (or a variant, or an orthologous region on chromosome 7) containing this QTL (QTL7.1 or a variant), is derived from an L. serriola line that is resistant to Fol-4 and / or Fol-1. In one aspect, the introgression fragment is the same introgression fragment found on chromosome 7 in seeds deposited under accession number NCIMB44108, or a smaller fragment carrying this QTL. The SNP markers SNP_01 to SNP_10 span a region of approximately 5 Mb on chromosome 7. In one aspect, the introgression fragment on chromosome 7 is 5 Mb or less in size, preferably 4.9 Mb or less in size, more preferably 4.5 Mb or 4.0 Mb or less in size, e.g., 3 Mb, 2 Mb, or 1.5 Mb or less. In one aspect, the introgression fragment is at least 0.2 Mb, 0.5 Mb, 1.0 Mb, 1.1 Mb, 1.5 Mb, 1.9 Mb, 2.0 Mb, 2.5 Mb, 2.7 Mb, or 3 Mb in size. Thus, encompassed herein are various ranges of introgression fragment sizes, such as fragments less than 5 Mb but greater than 0.2 Mb, fragments less than 4 Mb or 3 Mb but greater than 0.2 Mb, 0.5 Mb, 1 Mb, or 1.1 Mb, which carry QTL7.1 (or a variant) and one or more of the SNP markers SNP_01 to SNP_10, one or more of the SNP markers SNP_02 to SNP_09, or one or more of the SNP markers of the subgroups mentioned above. As described above, the location of QTL7.1 (or variants) in the region spanning SNP_01 to SNP_10 can be determined by fine mapping, and recombinants containing QTL7.1 (or variants) on smaller introgression fragments can be generated. The size of the introgression fragment can be easily determined, for example, by whole genome sequencing or next-generation sequencing. In particular, the introgression region can be easily distinguished from the genomic region of the cultivar due to genetic variation (SNPs, INDELs, etc.) in the introgression region.

[0161] To obtain the introgression fragment present on chromosome 7 (containing QTL7.1) from the deposited seeds (NCIMB44108) (i.e., to transfer the introgression fragment containing the QTL to another cultivated lettuce plant), plants are grown from the seeds and crossed with cultivated lettuce plants to obtain F1 seeds. Because NCIMB44108 contains two recombinant chromosomes 7 (containing introgression fragments), the F1 seeds and all plants grown therefrom contain one recombinant chromosome 7 from the NCIMB44108 parent and one non-recombinant chromosome 7 from the other cultivated parent. Therefore, recombinant chromosome 7 can be transferred from NCIMB44108 to other cultivated lettuce lines or varieties by conventional breeding. Plants containing QTL7.1 can be screened and selected for the presence of one or more of the above SNP markers to identify plants containing recombinant chromosome 7.

[0162] To generate the shorter introgression fragment (containing QTL7.1), meiosis must occur, and plants containing the recombinant chromosome 7 (especially new meiotic recombination events within the introgression fragment) must be identified. For example, seeds of NCIMB44108 can be selfed one or more times to generate S1, S2, or S3 plants (or additional selfed generations), and / or S1, S2, or S3 plants (and the like) containing the recombinant chromosome 7 can be backcrossed with the cultivated parent. Plants containing the recombinant chromosome 7 can be screened and selected for the presence of one or more of the SNP markers described above to identify plants containing the smaller introgression fragment. Such novel recombinants can then be tested for the presence of QTL7.1 on the smaller introgression fragment by determining the average disease score in Fol-4 and / or Fol-1 disease assays compared to a (genetic) control lacking the introgression fragment.

[0163] Similarly, cultivated lettuce plants containing QTL7.1 (or variants thereof) can be generated and / or identified using various methods. For example, to obtain cultivated lettuce plants containing an introgression fragment from a wild L. serriola donor, a wild L. serriola donor is identified that contains one or more SNP markers linked to QTL7.1 (or variants) disclosed herein (e.g., any one, more, or all of the markers described herein above). This can be done, for example, for multiple lines. The identified plants are crossed with cultivated lettuce plants to obtain F1 seeds. This F1 can be selfed to produce F2, F3, etc. plants, and / or the F2 or F3 plants, etc., can be backcrossed with the cultivated lettuce parent. Plants containing QTL7.1 (or variants thereof) may be screened and / or selected for the presence of one or more of the above SNP markers compared to the original cultivated parent (lacking the introgression) and / or screened and / or selected for the Fol-4 and / or Fol-1 resistance phenotype. Alternatively, or in addition, QTL mapping may be performed to identify additional molecular markers linked to QTL7.1 (or variants thereof) and / or to generate cultivated lettuce plants containing an introgression fragment on chromosome 7 that confers Fol-4 and / or Fol-1 resistance.

[0164] In one embodiment, the presence of the introgression fragment in a cultivated lettuce plant or in a chromosome 7 region (or a variant chromosome 7 region) comprising QTL7.1 is determined by: a) GG or GX genotype for single nucleotide polymorphism marker SNP_02 in SEQ ID NO: 2 (or a variant thereof); b) AA or AX genotype for single nucleotide polymorphism marker SNP_09 in SEQ ID NO: 9 (or a variant thereof); c) Any L. serriola genome-specific marker between markers SNP_02 and SNP_09 The gene can be detected by a molecular marker assay that detects at least 3, 4, 5, 6, 7, or 8 markers selected from the group consisting of:

[0165] In one aspect, the markers in c) are one or more of SNP_03 to SNP_08. In one aspect, at least 3, 4, 5, 6, 7, or 8 markers are detected from the markers in a), b), and / or c) above. In one embodiment, at least the markers in a) and / or b) are detected, and optionally at least 1, 2, 3, or more markers in c) are detected. In one aspect, at least one marker in c) includes SNP_07. In one aspect, the markers detected are consecutive markers.

[0166] Any L. serriola genome-specific marker between two markers refers to any molecular marker that is genetically located in the region of chromosome 7 between these two markers and / or that is physically located between these two markers and represents the L. serriola chromosome 7 region. This means that the marker is polymorphic between the cultivated L. sativa genome and the wild L. serriola genome. In one embodiment, the marker is a single nucleotide polymorphism (SNP), although other molecular markers such as INDELs, RFLPs, AFLPs, RAPDs, DNA sequencing, etc. may be used as well.

[0167] The introgression fragment in a plant of the invention is in one embodiment the fragment of chromosome 7 (containing QTL7.1) present in the seed deposited under accession number NCIMB44108, or a smaller version of this fragment (e.g., generated by recombination within the introgression fragment) carrying this QTL.

[0168] Also provided are seeds from which plants of the invention can grow, as well as heads or leaves harvested from plants of the invention and comprising a recombinant chromosome 7 (including QTL7.1 or a variant) in their genome. Also provided are plant cells, tissues, or plant parts of plants or seeds comprising at least one recombinant chromosome 7 (including QTL7.1 or a variant), wherein the recombinant chromosome 7 comprises an introgression fragment from an L. serriola line, and the introgression fragment comprises a QTL conferring Fol-4 and / or Fol-1 resistance (e.g., HR or IR resistance to either race). In one aspect, an L. serriola donor and QTL7.1 from this donor confer at least IR or HR resistance to race Fol-4, and optionally further IR or HR resistance to race Fol-1.

[0169] The molecular markers described herein can be detected according to standard methods. For example, SNP markers can be easily detected using KASP assays (see www.kpbioscience.co.uk) or other SNP genotyping assays. To develop a KASP assay, for example, 50 or 70 base pairs upstream and 50 or 70 base pairs downstream of the SNP can be selected, and two allele-specific forward primers and one allele-specific reverse primer can be designed. See, for example, Allen et al. 2011, Plant Biotechnology J. 9, 1086-1099, especially p. 097-1098 for the KASP assay method.

[0170] Thus, in one embodiment, the presence / absence of SNP markers and markers associated with QTL7.1 are determined using a KASP assay, although other SNP genotyping assays may be used as well, such as TaqMan SNP genotyping assays, high-resolution melting (HRM) assays, SNP genotyping arrays (e.g., Fluidigm, Illumina, etc.), or DNA sequencing.

[0171] The physical size of the introgression fragment can be determined by various methods, such as physical mapping, sequencing, or visualization of the introgression using fluorescence in situ hybridization (FISH) imaging (Verlaan et al. 2011, Plant Journal 68:1093-1103).

[0172] Cultivated lettuce plants having a smaller introgression fragment on chromosome 7 (including QTL7.1 or a variant) can be produced by generating new recombinant plants from a population of plants derived from a cross between a cultivated lettuce plant (lacking this introgression) and a plant of the invention, and selecting recombinant progeny having the smaller introgression size. Thus, such plants are, in one embodiment, derived from (progeny or descendants of) the recombinant chromosome 7 present in the plant whose seeds have been deposited under NCIMB 44108. Such progeny or descendants that retain QTL7.1 and therefore retain increased Fol-4 and / or Fol-1 resistance compared to plants lacking the introgression described herein are encompassed herein.

[0173] In one aspect, plants and plant parts comprising QTL7.1 (or variants thereof) comprise an introgression fragment comprising this QTL that is derivable or available (or derived or obtained) from NCIMB44108 or from an L. serriola donor that comprises the same SNP haplotype or SNP genotype for at least 3, 4, 5, 6, 7, 8, 9, or 10 of the SNP markers linked to QTL7.1. The wild donor comprises at least Fol-4 resistance, but optionally also Fol-1 resistance (i.e., double resistance).

[0174] The lettuce plant, seed, plant part, cell, or tissue containing QTL7.1 (or a variant) can be any type of lettuce plant suitable for outdoor or indoor cultivation (e.g., baby leaf, romaine, iceberg, etc.). The Lactuca sativa plants of the present invention can be head or non-heading types of lettuce. In one aspect, the Lactuca sativa plants of the present invention are of the head lettuce type, teen leaf type, loose leaf type, or baby leaf type.

[0175] Since QTL7.1 (or variant) has an additive effect, the lettuce plant, seed, plant part, cell or tissue preferably contains a homozygous form of QTL7.1 (or variant).

[0176] References herein to lettuce plants include plant parts (e.g., heads, leaves, leaf parts, etc.), tissues, cells, as well as seeds from which such plants may grow.

[0177] Preferably, the plants have good agronomic quality characteristics. The plants are, in one aspect, both genetically and phenotypically uniform.

[0178] In one aspect, the lettuce plant is a plant whose seeds have been deposited under accession number NCIMB441108, or a progeny thereof, whereby the progeny carry QTL7.1 (detectable by the presence of one or more markers described elsewhere).

[0179] A further embodiment of the present invention is a plant cell, tissue or plant part of a plant or seed according to the present invention comprising at least one recombinant chromosome 7, said recombinant chromosome 7 comprising an introgression fragment comprising QTL7.1 (or a variant) as described.

[0180] In one aspect, a Lactuca sativa plant of the present invention comprising QTL7.1 from L. serriola is an inbred, diploid, or hybrid plant. Thus, in one aspect, the present invention provides that the plant of the present invention is an inbred. Such inbred plants are highly homozygous, for example, by repeated selfing or self-pollination processes. In one aspect, the present disclosure provides haploid and / or diploid (double haploid) plants of the plants of the present invention encompassed herein, comprising QTL7.1 (or a variant) described herein. Haploid and diploid plants can be produced, for example, by anther or microspore culture and regeneration into whole plants. For diploid production, chromosome doubling can be induced using known methods, such as colchicine treatment. Thus, in one aspect, a Lactuca sativa plant is provided that includes a described QTL7.1 (or variant), wherein the plant is a dihaploid plant.

[0181] The plants provided by the present invention can be used to produce food or feed. Thus, the present invention provides the use of the Lactuca sativa plants provided herein as consumable crops. In particular, harvested leaves and / or harvested heads produced by the plants of the present invention can be advantageously used as consumable crops.

[0182] The plants provided by the present invention can be used to produce propagation material. Such propagation material includes propagation material suitable for and / or resulting from sexual reproduction, such as pollen and seeds. Such propagation material also includes propagation material suitable for and / or resulting from asexual or vegetative reproduction, including, but not limited to, cuttings, explants, tubers, cell cultures, and tissue cultures. Therefore, the present invention further provides the use of the Lactuca sativa plants provided herein as a source of propagation material.

[0183] In one aspect, the present invention provides seeds from which the Lactuca sativa plants of the present invention can be grown. Additionally, the present invention provides a plurality of such seeds. Seeds of the present invention can be distinguished from other seeds phenotypically (based on plants having the Fol-4 and / or Fol-1 resistance phenotype of the present invention) and / or due to the presence of QTL7.1 (or a variant, or an introgression fragment comprising QTL7.1 or a variant) described herein using molecular methods to detect SNP markers linked to a QTL or SNP markers indicative of an introgression fragment in cells or tissues, e.g., molecular genotyping methods to detect an introgression fragment of the present invention, or sequencing.

[0184] Also provided is a method of identifying (detecting or selecting) a cultivated L. sativa plant or plant part comprising an introgression fragment on chromosome 7 comprising QTL7.1 (or a variant thereof), said introgression fragment or said QTL7.1 (or a variant thereof) as found, for example, in NCIMB44108 or an L. serriola donor, the method comprising: a) providing a cultivated L. sativa plant or plant part, or DNA of such a plant or plant part; b) screening the plant, plant part, or DNA using a molecular marker assay that detects at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 SNP markers selected from SNP_01 to SNP_10 or SNP_02 to SNP_09 to detect an introgression fragment on chromosome 7 containing QTL7.1 (or a variant); and c) identifying and / or selecting plants containing donor SNP nucleotides (donor SNP haplotypes or donor SNP genotypes) for at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 of SNP_01 to SNP_10 or SNP_02 to SNP_09 to detect the introgression fragment on chromosome 7 containing QTL7.1 (or a variant); A method is provided, comprising:

[0185] Further provided is a method for producing an L. sativa plant comprising an introgression fragment on chromosome 7 comprising QTL7.1 (or a variant thereof), the method comprising: a) providing a first lettuce (L. sativa) plant comprising a homozygous recombinant chromosome 7 harboring an introgression fragment comprising QTL7.1 (or a variant thereof) and comprising donor SNP nucleotides (donor SNP haplotypes or donor SNP genotypes) for at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 of the SNP markers linked to this QTL, wherein optionally the introgression fragment or the QTL7.1 is derivable (or derived) from NCIMB44108; b) providing a second lettuce (L. sativa) plant; c) crossing the lettuce plant of a) with the lettuce plant of b); d) recovering seeds from said cross. A method comprising:

[0186] The harvested seeds are also an embodiment of the present invention.

[0187] In another aspect, there is provided a method of generating offspring of NCIMB44108, comprising: a) growing plants from seeds deposited under accession number NCIMB44108; b) selfing the plant one or more times and / or crossing the plant with another L. sativa plant one or more times to produce progeny seed; c) The following: i) SNP_01 to SNP_10 or SNP_02 to SNP_09 screening the progeny seeds, or plants grown from the seeds, or parts of the seeds or plants, using a molecular marker assay that detects at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or more SNP markers from d) identifying and / or selecting progeny plants containing donor SNP nucleotides (donor SNP haplotypes or donor SNP genotypes) for at least one, two, three, four, five, six, seven, eight, nine, or ten of SNP_01 to SNP_10 or SNP_02 to SNP_09 to detect the introgression fragment on chromosome 7 containing QTL7.1; A method is provided that includes:

[0188] The donor SNP nucleotides (or haplotypes or genotypes) are described above and in Tables 1-3.

[0189] Further provided is a method for identifying and / or selecting a wild L. serriola donor plant containing QTL7.1 (or a variant thereof), comprising: a)See below: i)SNP_01~SNP_10 or SNP_02~SNP_09 screening seeds or seed parts, or plants or plant parts, or DNA of such plants, seeds, or plant parts of one or more L. serriola lines to detect an introgression fragment on chromosome 7 containing QTL7.1 (or a variant) using a molecular marker assay that detects at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 SNP markers from b) identifying and / or selecting L. serriola lines containing donor SNP nucleotides (donor SNP haplotypes or donor SNP genotypes) for at least one, two, three, four, five, six, seven, eight, nine, or ten of SNP_01 through SNP_10 or SNP_02 through SNP_09 to detect introgression fragments on chromosome 7 containing QTL7.1 (or variants); The method includes:

[0190] The method may also optionally include selfing the wild L. serriola line one or more times, for example prior to step a).

[0191] Wild accessions can be derived from seed depositories such as, for example, the USDA ARS-GRIN collection, the CGN collection, and the like.

[0192] The method may also include testing one or more L. serriola lines in a Fol-4 and / or Fol-1 resistance assay, which may be performed, for example, prior to the molecular marker assay of step a), before selfing the lines, or after selfing the lines, and / or after step b), i.e., after selection or identification of one or more lines that contain the same or similar SNP haplotypes or SNP genotypes as set forth in Tables 1-3 (e.g., a QTL7.1 (or variant) SNP haplotype having donor nucleotides for at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 of the SNP markers linked to QTL7.1 (or variants thereof)). One or more L. serriola lines may be selected for lines (or their selfed progeny) having an average Fol-4 and / or Fol-1 disease score of 2.0 or less, preferably 1.5 or less, for example 1.0 or less, using, for example, the protocols described in the Examples, or one or more L. serriola lines may be selected for lines having significantly increased Fol-4 and / or Fol-1 resistance compared to a susceptible control variety included in a disease assay.

[0193] Also provided is a method for introducing QTL7.1 (or a variant thereof) from an L. serriola donor into an L. sativa plant, comprising: a) To detect the introgression fragment on chromosome 7 containing QTL7.1 (or a variant), i)SNP_01~SNP_10 or SNP_02~SNP_09 The donor SNP nucleotides (donor SNP haplotypes or donor SNP genotypes) for at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 of and optionally providing an L. serriola line (or progeny thereof obtained by selfing one or more times) having an average Fol-4 and / or Fol-1 disease score of 2.0 or less, preferably 1.5 or less, for example 1.0 or less, or optionally having significantly increased Fol-4 and / or Fol-1 resistance compared to a control; b) crossing the line with an L. sativa plant to obtain F1, F2, F3, or further self-crossed generations, or BC1, BC2, BC3, or further backcrossed generation progeny, and optionally c) selecting progeny plants containing QTL7.1 (or a variant) from the L. serriola line of step a). Also provided is a method comprising:

[0194] Progeny plants produced by the above methods are also an aspect of the present invention.

[0195] Also provided herein are containers and packages containing or including seeds from which plants of the invention can be grown, which can be labeled as containing L. sativa seeds that will produce plants with Fusarium wilt resistance to at least races Fol-4 and / or Fol-1.

[0196] Also provided are progeny seeds and plants of plants of the invention that retain an introgression on chromosome 7 containing QTL7.1 (or a variant), or that contain a smaller introgression fragment (e.g., derivable from a fragment present in NCIMB44108) containing QTL7.1 or a variant QTL7.1 that still confers Fol-4 and / or Fol-1 resistance (i.e., still contains this QTL). Progeny can be any generation obtained by selfing a lettuce plant of the invention and / or by crossing a lettuce plant of the invention with another lettuce plant one or more times.

[0197] Thus, progeny are the generation (seed) produced from the first cross (F1) or self (S1), or any further generation produced by crossing and / or selfing (F2, F3, etc.) and / or backcrossing (BC1, BC2, etc.) one or more selected plants of the F1, and / or S1, and / or BC1 generations (or any further generation plants, e.g., F2) with another L. sativa plant. The progeny are preferably selected to retain the introgression fragment from L. serriola containing QTL7.1 (or a variant thereof). As such, the progeny also have an increased Fol-4 and / or Vol-1 resistance phenotype and preferably have at least the same average disease score as the plants used in the initial cross or self. The presence (or retention) of the introgression fragment containing the QTL can be determined phenotypically and / or using molecular marker assays described herein. With regard to phenotypic evaluation, the additive nature of QTLs must of course be taken into account.

[0198] In a further aspect, parts of the L. sativa plants of the present invention are provided. Parts include, for example, cells and cell cultures, tissue cultures, vegetative plant tissues (e.g., leaves, roots), flowers, pollen, embryos, etc. The plant parts contain an introgression fragment on chromosome 7 that is described and can be detected using one or more of the described markers. Furthermore, when whole plants are regenerated from such parts (e.g., cells, cell or tissue cultures), the regenerated plants contain a recombinant chromosome 7.

[0199] Therefore, also provided is a plant cell, tissue, or plant part of a plant or seed according to the present invention comprising at least one recombinant chromosome 7, said recombinant chromosome 7 comprising an introgression fragment from a L. serriola donor plant, said introgression fragment comprising a QTL that confers Fol-4 and / or Fol-1 resistance selected from QTL7.1 or a variant thereof.

[0200] Also encompassed herein are in vitro cell cultures and in vitro tissue cultures of cells or tissues comprising the described recombinant chromosome 7. Preferably, the cells or tissues can be regenerated into whole lettuce plants, i.e., the cells are regenerable cells and the tissues comprise regenerable cells. Thus, vegetative propagation of plants according to the present invention is also an embodiment herein. Thus, vegetatively propagated L. sativa plants are provided that comprise the described recombinant chromosome 7. In a different aspect, non-proliferating cells that comprise QTL7.1 (or a variant thereof) conferring Fol-4 and / or Fol-1 resistance are encompassed herein, as are tissues comprising such cells.

[0201] In a particular embodiment, heads or leaves harvested from plants according to the invention are provided.

[0202] Also provided is a container or package containing or consisting of harvested heads or leaves, again in which the cells of the head or leaf are distinguishable from other heads or leaves by the presence of QTL7.1 (or a variant thereof) (which can be determined by one or more of the molecular marker assays).

[0203] The present invention also provides food or feed products comprising or consisting of the plant parts described herein (preferably, the heads or leaves described herein). The food or feed products may be fresh or processed, for example, pickled, canned, steamed, boiled, fried, blanched, and / or frozen. Also provided herein are containers (e.g., cans, boxes, crates, bags, cartons), modified atmosphere packaging, films (e.g., biodegradable films), and the like, containing the plant parts, such as the heads or leaves described herein.

[0204] Methods and Uses According to the Invention In a further embodiment, the present invention provides a method for producing novel cultivated lettuce plants comprising an introgression fragment on chromosome 7 comprising QTL7.1 or a variant thereof, wherein the QTL confers Fol-4 and / or Fol-1 resistance, as described, in either a homozygous or heterozygous form relative to a control plant. The method comprises crossing a plant of the present invention or its progeny plant, as either the male or female parent, with another lettuce plant one or two times, and / or selfing a lettuce plant of the present invention or its progeny plant one or more times, and selecting progeny from the crosses and / or selfs.

[0205] Therefore, methods are provided for introducing a recombinant chromosome 7 containing QTL7.1 or a variant thereof from one (cultivated) lettuce plant into another (cultivated) lettuce plant, in particular into a lettuce variety or breeding line in which Fusarium Fol-4 and / or Fol-1 resistance is to be introduced or increased.

[0206] This method is a) providing a first cultivated lettuce plant comprising an introgression fragment comprising, preferably homozygous, QTL7.1 (or a variant thereof); b) providing a second cultivated lettuce plant, in particular a plant having a wild-type (non-recombinant) chromosome 7 or a plant lacking QTL7.1; c) crossing the lettuce plant of a) with the lettuce plant of b); d) recovering F1 hybrid seeds from said cross; and e) optionally selfing plants grown from the F1 hybrid seeds to produce F2 seeds or further selfed generations, and / or backcrossing the seeds to produce a backcross generation, and optionally selecting F2 seeds, or further selfed generation seeds, or backcross generation seeds that have QTL7.1 (or a variant thereof); and f) optionally further breeding plants grown from said F1 or F2 or further generation selfed seeds or backcross generation seeds to generate lettuce plants with good agronomic characteristics and homozygous or heterozygous for QTL7.1 (or a variant thereof). Includes.

[0207] The presence or absence of an introgression fragment comprising QTL7.1 (or a variant thereof) may be determined by one or more of the molecular marker assays described herein and / or by determining whether Fol-4 and / or Fol-1 resistance is significantly increased, for example, compared to the plant of step b). Further breeding in step e) or f) may include selfing, crossing, creating doubled haploids, backcrossing, and combinations thereof (e.g., backcrossing and selfing), etc. Plants, plant parts, and seeds obtained by the above methods are encompassed herein.

[0208] In one aspect, the plant of step a) may be a plant grown from seeds deposited in NCIMB44108 or a progeny thereof, or may be a plant that comprises QTL7.1 (or a variant thereof) that is present in another wild L. serriola donor line that contains, for example, the same SNP haplotype or genotype for at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 markers linked to the QTL (e.g., as described in Tables 1-3).

[0209] In a different aspect, there is provided a method of producing a cultivated lettuce plant comprising an introgression fragment on chromosome 7, said introgression fragment comprising QTL7.1 or a variant thereof, said method comprising: a) providing a first cultivated lettuce (L. sativa) plant; b) providing a second wild L. serriola plant, said plant comprising QTL7.1 or a variant thereof, determinable by the presence of one or more SNP markers described herein (particularly determinable by the presence of a donor SNP haplotype or genotype for at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 SNP markers linked to the QTL); c) crossing the lettuce plant of a) with the lettuce plant of b); d) recovering F1 seeds from the cross and backcrossing the F1 plants to the lettuce plants of a) to produce a backcross (BC1) population, or selfing the F1 plants one or more times to produce an F2, or F3, or higher generation selfed population; e) optionally backcrossing the plants of d) one or more times to the lettuce plants of a) to generate a higher generation backcross population; and f) identifying F2, F3, or higher generation inbred plants or BC1 or higher generation backcross plants containing an introgression on chromosome 7, wherein the introgression fragment comprises QTL7.1 or a variant thereof; A method is provided, comprising:

[0210] When a backcross population is referred to in this method, the backcross population may also be selfed, ie, BC1S1, BC1S2, BC2S1, BC2S2, etc.

[0211] In one or more of steps b) to f), the presence of the QTL (or introgression fragment containing this QTL) may be tested (and plants selected) by carrying out molecular marker assays as described elsewhere herein, for example by determining whether the plants contain one or more of the SNP markers linked to QTL7.1 (e.g. one or more of SNP_01 to SNP_10 or SNP_02 to SNP_09), and / or by testing for disease resistance to Fol-4 and / or Fol-1.

[0212] This method can be used to generate and / or select novel cultivated lettuce plants containing an introgression harboring QTL7.1 or a variant thereof from an L. serriola donor. In one aspect, the L. serriola in step b) is selected from a donor that contains at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 SNP markers (SNP haplotypes or SNP genotypes) linked to the QTL (see, e.g., Tables 1-3) and that contains Fol-4 and / or Fol-1 resistance (e.g., an average Fol-4 disease score of 2.0, 1.5, or 1.0 or less, or significantly increased Fol-4 and / or Fol-1 resistance compared to susceptible control plants).

[0213] In one aspect, there is provided a method of producing a cultivated lettuce plant comprising an introgression fragment on chromosome 7, wherein the introgression fragment comprises QTL7.1 or a variant thereof, the method comprising: a) providing a first cultivated lettuce plant; b) providing a second wild L. serriola, the second wild L. serriola comprising at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 of the SNP markers (SNP haplotypes or SNP genotypes) linked to QTL7.1, and optionally having an average Fol-4 and / or Fol-1 disease score of less than or equal to 2.0, 1.5, or 1.0, or optionally having significantly increased resistance to Fol-4 and / or Fol-1 compared to a control; c) crossing the plant of a) with the plant of b); d) harvesting F1 seeds from the cross and backcrossing the F1 plants to plants of a) to produce a backcross (BC1) population, or selfing the F1 plants one or more times to produce an F2 or F3 population; e) optionally selfing the backcross population to generate, for example, a BC1S1 or BC1S2 population; f) identifying F2, F3, BC1, BC1S1, or BC1S2 plants containing the SNP marker(s). A method comprising:

[0214] Also provided is a method for identifying a wild L. serriola plant containing a Fol-4 and / or Fol-1 resistance QTL on chromosome 7, comprising: A) Preparing an L. serriola strain or strains; B) screening the lines using a molecular marker assay that detects at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 SNP markers linked to QTL7.1; C)Below: a) the AX or AA genotype of single nucleotide polymorphism marker SNP_01 at nucleotide 101 of SEQ ID NO: 1, or SEQ ID NO: 11, or SEQ ID NO: 21 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO: 1, or SEQ ID NO: 11, or SEQ ID NO: 21); (This marker is optional, as it is a flanking marker that bounds the QTL-containing region on one side.) b) the GX or GG genotype of single nucleotide polymorphism marker SNP_02 at nucleotide 101 of SEQ ID NO:2, or SEQ ID NO:12, or SEQ ID NO:22 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:2, or SEQ ID NO:12, or SEQ ID NO:22); c) the CX or CC genotype of single nucleotide polymorphism marker SNP_03 at nucleotide 101 of SEQ ID NO:3, or SEQ ID NO:13, or SEQ ID NO:23 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:3, or SEQ ID NO:13, or SEQ ID NO:23); d) the AX or AA genotype of single nucleotide polymorphism marker SNP_04 at nucleotide 101 of SEQ ID NO:4, or SEQ ID NO:14, or SEQ ID NO:24 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:4, or SEQ ID NO:14, or SEQ ID NO:24); e) the GX or GG genotype of single nucleotide polymorphism marker SNP_05 at nucleotide 101 of SEQ ID NO:5, or SEQ ID NO:15, or SEQ ID NO:25 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:5, or SEQ ID NO:15, or SEQ ID NO:25); f) the GX or GG genotype of single nucleotide polymorphism marker SNP_06 at nucleotide 101 of SEQ ID NO:6, or SEQ ID NO:16, or SEQ ID NO:26 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:6, or SEQ ID NO:16, or SEQ ID NO:26); g) the TX or TT genotype of single nucleotide polymorphism marker SNP_07 at nucleotide 101 of SEQ ID NO:7, or SEQ ID NO:17, or SEQ ID NO:27 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:7, or SEQ ID NO:17, or SEQ ID NO:27); h) the TX or TT genotype of single nucleotide polymorphism marker SNP_08 at nucleotide 101 of SEQ ID NO:8, or SEQ ID NO:18, or SEQ ID NO:28 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:8, or SEQ ID NO:18, or SEQ ID NO:28); i) the AX or AA genotype of single nucleotide polymorphism marker SNP_09 at nucleotide 101 of SEQ ID NO:9, or SEQ ID NO:19, or SEQ ID NO:29 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:9, or SEQ ID NO:19, or SEQ ID NO:29); j) the GX or GG genotype of single nucleotide polymorphism marker SNP_10 at nucleotide 101 of SEQ ID NO: 10, or SEQ ID NO: 20, or SEQ ID NO: 30 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO: 10, or SEQ ID NO: 20, or SEQ ID NO: 30); (This marker is optional, as it is a flanking marker that delimits the QTL-containing region on the other side.) and / or selecting lines derived from b) that contain at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 SNP haplotypes or SNP genotypes of the SNP markers linked to the QTL selected from: D) Optionally, introgressing the QTL from the wild accession into cultivated lettuce (e.g., by backcrossing). The method includes:

[0215] Steps B), C), and D) may use, for example, SNP genotyping assays (such as KASP assays), but other molecular marker assays may also be used. This also applies to the other methods described herein. Thus, this method allows for screening wild L. serriola accessions for the presence of one or more of the markers linked to QTL7.1, and for introgressing this QTL into cultivated lettuce plants. Plants and seeds obtained by this method also represent one embodiment of the present invention.

[0216] Also provided is a method for identifying a wild L. serriola plant containing a Fol-4 and / or Fol-1 resistance QTL on chromosome 7, comprising: A) Providing one or more L. serriola plants; B) optionally, testing the L. serriola plant or plants for resistance to Fusarium races Fol-4 and / or Fol-1, e.g., in a disease assay; C) screening the genomic DNA of the plant or plants of A) or optionally only the Fol-4 and / or Fol-1 resistant plants identified in B) for the presence of one or more markers indicative of QTL7.1; and D) identifying plants and / or selecting plants containing one or more markers of C); E) Optionally, testing the plants of D) for resistance to Fusarium race Fol-4 and / or Fol-1. Including, The markers representing QTL7.1 are: a) the AX or AA genotype of single nucleotide polymorphism marker SNP_01 at nucleotide 101 of SEQ ID NO: 1, or SEQ ID NO: 11, or SEQ ID NO: 21 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO: 1, or SEQ ID NO: 11, or SEQ ID NO: 21); (This marker is optional, as it is a flanking marker that bounds the QTL-containing region on one side.) b) the GX or GG genotype of single nucleotide polymorphism marker SNP_02 at nucleotide 101 of SEQ ID NO:2, or SEQ ID NO:12, or SEQ ID NO:22 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:2, or SEQ ID NO:12, or SEQ ID NO:22); c) the CX or CC genotype of single nucleotide polymorphism marker SNP_03 at nucleotide 101 of SEQ ID NO:3, or SEQ ID NO:13, or SEQ ID NO:23 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:3, or SEQ ID NO:13, or SEQ ID NO:23); d) the AX or AA genotype of single nucleotide polymorphism marker SNP_04 at nucleotide 101 of SEQ ID NO:4, or SEQ ID NO:14, or SEQ ID NO:24 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:4, or SEQ ID NO:14, or SEQ ID NO:24); e) the GX or GG genotype of single nucleotide polymorphism marker SNP_05 at nucleotide 101 of SEQ ID NO:5, or SEQ ID NO:15, or SEQ ID NO:25 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:5, or SEQ ID NO:15, or SEQ ID NO:25); f) the GX or GG genotype of single nucleotide polymorphism marker SNP_06 at nucleotide 101 of SEQ ID NO:6, or SEQ ID NO:16, or SEQ ID NO:26 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:6, or SEQ ID NO:16, or SEQ ID NO:26); g) the TX or TT genotype of single nucleotide polymorphism marker SNP_07 at nucleotide 101 of SEQ ID NO:7, or SEQ ID NO:17, or SEQ ID NO:27 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:7, or SEQ ID NO:17, or SEQ ID NO:27); h) the TX or TT genotype of single nucleotide polymorphism marker SNP_08 at nucleotide 101 of SEQ ID NO:8, or SEQ ID NO:18, or SEQ ID NO:28 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:8, or SEQ ID NO:18, or SEQ ID NO:28); i) the AX or AA genotype of single nucleotide polymorphism marker SNP_09 at nucleotide 101 of SEQ ID NO:9, or SEQ ID NO:19, or SEQ ID NO:29 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:9, or SEQ ID NO:19, or SEQ ID NO:29); j) the GX or GG genotype of single nucleotide polymorphism marker SNP_10 at nucleotide 101 of SEQ ID NO: 10, or SEQ ID NO: 20, or SEQ ID NO: 30 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO: 10, or SEQ ID NO: 20, or SEQ ID NO: 30); (This marker is optional, as it is a flanking marker that delimits the QTL-containing region on the other side.) A method selected from the group consisting of:

[0217] In yet another aspect, there is provided a method for identifying cultivated lettuce plants which comprise an introgression fragment on chromosome 7, said introgression fragment comprising a Fol-4 and / or Fol-1 resistance QTL, said method comprising screening cultivated lettuce plants, or a population of cultivated lettuce plants, or parts of such lettuce plants (e.g., cells, DNA) using a molecular marker assay to detect at least one SNP marker (preferably 2, 3, 4, 5 or more; preferably contiguous SNP markers) indicative of (linked to) QTL7.1 (or a variant thereof) as described elsewhere herein.

[0218] This method may use any of the molecular marker tests described elsewhere herein and may therefore be used to detect the presence of an introgression fragment containing QTL7.1 (or a variant thereof) in a cultivated lettuce plant or plant part.

[0219] In yet another aspect, there is provided a method for detecting whether a cultivated lettuce plant comprises an introgression fragment on chromosome 7, said introgression fragment comprising QTL7.1 (or a variant thereof), said method comprising: a) providing a cultivated lettuce plant or plant part; b)Below: screening the plant or plant part (or DNA obtained from the plant or plant part) using a molecular marker assay that detects at least one (preferably at least 2, 3, 4, 5, 6, 7, 8, 9, 10, or more) SNP marker selected from the group consisting of SNP_01 to SNP_10 linked to QTL7.1 (or variants thereof); or SNP_02 to SNP_09 linked to QTL7.1 (or variants thereof). A method is provided, comprising:

[0220] Further provided is a method of screening cultivated lettuce lines or varieties for the presence of QTL7.1, comprising: A) providing a cultivated lettuce plant or a plurality of cultivated lettuce plants; B) optionally testing the cultivated lettuce plant or plants for resistance to Fusarium race Fol-4 and / or Fol-1, e.g., in a disease assay; C) screening the genomic DNA of the plant or plants of A) or optionally only the Fol-4 and / or Fol-1 resistant plants identified in B) for the presence of one or more markers indicative of QTL7.1; and D) identifying and / or selecting plants containing one or more markers of C); E) Optionally, testing the plants of D) for resistance to Fusarium race Fol-4 and / or Fol-1. Including, The markers representing QTL7.1 are: a) the AX or AA genotype of single nucleotide polymorphism marker SNP_01 at nucleotide 101 of SEQ ID NO: 1, or SEQ ID NO: 11, or SEQ ID NO: 21 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO: 1, or SEQ ID NO: 11, or SEQ ID NO: 21); (This marker is optional as it is a flanking marker) b) the GX or GG genotype of single nucleotide polymorphism marker SNP_02 at nucleotide 101 of SEQ ID NO:2, or SEQ ID NO:12, or SEQ ID NO:22 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:2, or SEQ ID NO:12, or SEQ ID NO:22); c) the CX or CC genotype of single nucleotide polymorphism marker SNP_03 at nucleotide 101 of SEQ ID NO:3, or SEQ ID NO:13, or SEQ ID NO:23 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:3, or SEQ ID NO:13, or SEQ ID NO:23); d) the AX or AA genotype of single nucleotide polymorphism marker SNP_04 at nucleotide 101 of SEQ ID NO:4, or SEQ ID NO:14, or SEQ ID NO:24 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:4, or SEQ ID NO:14, or SEQ ID NO:24); e) the GX or GG genotype of single nucleotide polymorphism marker SNP_05 at nucleotide 101 of SEQ ID NO:5, or SEQ ID NO:15, or SEQ ID NO:25 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:5, or SEQ ID NO:15, or SEQ ID NO:25); f) the GX or GG genotype of single nucleotide polymorphism marker SNP_06 at nucleotide 101 of SEQ ID NO:6, or SEQ ID NO:16, or SEQ ID NO:26 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:6, or SEQ ID NO:16, or SEQ ID NO:26); g) the TX or TT genotype of single nucleotide polymorphism marker SNP_07 at nucleotide 101 of SEQ ID NO:7, or SEQ ID NO:17, or SEQ ID NO:27 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:7, or SEQ ID NO:17, or SEQ ID NO:27); h) the TX or TT genotype of single nucleotide polymorphism marker SNP_08 at nucleotide 101 of SEQ ID NO:8, or SEQ ID NO:18, or SEQ ID NO:28 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:8, or SEQ ID NO:18, or SEQ ID NO:28); i) the AX or AA genotype of single nucleotide polymorphism marker SNP_09 at nucleotide 101 of SEQ ID NO:9, or SEQ ID NO:19, or SEQ ID NO:29 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO:9, or SEQ ID NO:19, or SEQ ID NO:29); j) the GX or GG genotype of single nucleotide polymorphism marker SNP_10 at nucleotide 101 of SEQ ID NO: 10, or SEQ ID NO: 20, or SEQ ID NO: 30 (or nucleotide 101 in a variant thereof comprising at least 95%, 96%, 97%, 98%, or 99% sequence identity to SEQ ID NO: 10, or SEQ ID NO: 20, or SEQ ID NO: 30); (This marker is optional as it is a flanking marker) A method selected from the group consisting of:

[0221] Thus, in one aspect, there is provided a method for detecting or selecting L. sativa or L. serriola plants, or plant parts, or seeds, comprising QTL7.1, for example, comprising the following SNP markers: - a guanine (G) for SNP_02 at nucleotide 101 of SEQ ID NO: 2 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 2, - a cytosine (C) for SNP_03 at nucleotide 101 of SEQ ID NO: 3 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 3, - an adenine (A) for SNP_04 at nucleotide 101 of SEQ ID NO: 4 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 4, - a guanine (G) for SNP_05 at nucleotide 101 of SEQ ID NO: 5 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 5, - a guanine (G) for SNP_06 at nucleotide 101 of SEQ ID NO: 6 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 6, - a thymine (T) for SNP_07 at nucleotide 101 of SEQ ID NO: 7 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 7, - a thymine (T) for SNP_08 at nucleotide 101 of SEQ ID NO: 8 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 8, - an adenine (A) for SNP_09 at nucleotide 101 of SEQ ID NO: 9 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 9 determining the presence in the genome of at least 2, 3, 4, 5, 6, 7, or 8 plants, plant parts, or seeds of and optionally selecting a plant, or plant part, or seed comprising said SNP marker.

[0222] The method further comprises: - testing plants or seeds comprising said at least 2, 3, 4, 5, 6, 7 or 8 SNP markers for resistance to Fusarium races Fol-4 and / or Fol-1, and optionally selecting plants or seeds comprising resistance to Fusarium races Fol-4 and / or Fol-1. may include:

[0223] Similarly, there is provided a method for detecting or selecting a plant, plant part, or seed of, for example, L. sativa or L. serriola, comprising QTL7.1, the method comprising: I) testing a plant or seed (or multiple plants or seeds) for resistance to Fusarium race Fol-4 and / or Fol-1; and II) The following SNP markers: - a guanine (G) for SNP_02 at nucleotide 101 of SEQ ID NO: 2 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 2, - a cytosine (C) for SNP_03 at nucleotide 101 of SEQ ID NO: 3 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 3, - an adenine (A) for SNP_04 at nucleotide 101 of SEQ ID NO: 4 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 4, - a guanine (G) for SNP_05 at nucleotide 101 of SEQ ID NO: 5 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 5, - a guanine (G) for SNP_06 at nucleotide 101 of SEQ ID NO: 6 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 6, - a thymine (T) for SNP_07 at nucleotide 101 of SEQ ID NO: 7 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 7, - a thymine (T) for SNP_08 at nucleotide 101 of SEQ ID NO: 8 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 8, - an adenine (A) for SNP_09 at nucleotide 101 of SEQ ID NO: 9 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 9 determining the presence in the genome of at least 2, 3, 4, 5, 6, 7, or 8 plants, plant parts, or seeds of and optionally, III) Selecting plants, plant parts, or seeds containing Fol-4 and / or Fol-1 resistance and at least 2, 3, 4, 5, 6, 7, or 8 of the SNP markers A method is provided that includes:

[0224] The order of steps I and II) may be reversed, so that first the presence of one or more donor SNP markers linked to and representing QTL7.1 in the genome may be determined, and then plant lines or seeds (i.e. plants grown from this plant) may be tested for the resistance phenotype conferred by QTL7.1 or variants thereof.

[0225] Molecular marker screening obviously involves obtaining plant material and analyzing the genomic DNA of this material for SNP marker haplotypes or genotypes.

[0226] The methods may also use other molecular marker tests described elsewhere herein.

[0227] Also encompassed herein is a method of producing a cultivated lettuce plant comprising an introgression fragment on chromosome 7, said introgression fragment comprising QTL7.1 (or a variant thereof), the method comprising: a) providing a first cultivated lettuce plant, preferably lacking QTL7.1; b) providing a second cultivated lettuce plant selected from a plant grown from the seed deposited under accession number NCIMB44108, or a progeny thereof, or providing a second cultivated lettuce plant or a wild L. serriola plant comprising at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 resistance donor SNP haplotypes or genotypes that contain and are linked to QTL7.1 (or a variant thereof); c) crossing the plant of a) with the plant of b); d) collecting F1 seeds from the cross and optionally selfing the F1 plants one or more times to produce an F2 or F3 population, or to produce further selfed populations; e) optionally backcrossing this F1 plant, or an F2 or F3 or further selfed plant, to a plant of a) to produce a backcross population; f) optionally selfing this backcross population one or more times; g) identifying F1 plants, F2 plants, F3 plants, further selfed plants, or backcross plants that contain resistance donor SNP haplotypes or genotypes for at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 SNP markers linked to the QTL; The method includes:

[0228] In another aspect, there is provided a method of generating offspring of NCIMB44108 carrying QTL7.1, comprising: a) growing plants from seeds deposited under accession number NCIMB44108; b) selfing said plant one or more times or crossing said plant one or more times with another cultivated lettuce plant to produce progeny seed; c) screening the progeny seeds, or plants grown from the seeds, or parts of the seeds or plants, using a molecular marker assay that detects at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 SNP markers disclosed herein as linked to QTL7.1; d) identifying and / or selecting progeny plants that contain resistance donor SNP haplotypes or genotypes of at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 SNP makers linked to a QTL (as described elsewhere herein); and e) optionally confirming the Fol-4 and / or Fol-1 resistance of said progeny plants. A method is provided that includes:

[0229] 1. A method for generating offspring of NCIMB44108, comprising: a) growing plants from seeds deposited under accession number NCIMB44108; b) selfing the plant one or more times or crossing the plant one or more times with another lettuce plant to produce progeny seed; c) screening the progeny seeds, or plants grown from the seeds, or parts of the seeds or plants, using a molecular marker assay to detect at least 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 SNP markers linked to QTL7.1, SNP_01 to SNP_10 to detect the introgression fragment containing QTL7.1; or SNP_02 to SNP_09 to detect the introgression fragment containing QTL7.1 That is, screening; d) The following: i) at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 markers among SNP_01 to SNP_10 having a resistant donor SNP haplotype; and / or ii) at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 markers among SNP_02 to SNP_09 having a resistant donor SNP haplotype; and / or iii) identifying and / or selecting progeny plants that contain at least SNP_07 and one, two, or three additional markers flanking SNP_07 selected from SNP_04, SNP_05, SNP_06, SNP_08, SNP_09 that have a resistance donor SNP haplotype; e) optionally confirming the Fol-4 and / or Fol-1 resistance of said progeny plants. A method is provided that includes:

[0230] Progeny plants produced by any of the above methods are also an aspect of the invention.

[0231] Using the methods and markers described herein, it is also possible to reduce the size of the introgression fragment containing the QTL, i.e., to generate and select recombinants with smaller introgression fragments but which retain the QTL.

[0232] In one aspect, the invention encompasses the use of a recombinant chromosome 7 comprising an introgression fragment from an L. serriola line, for breeding a lettuce variety with Fol-4 and / or Fol-1 resistance (particularly double resistance), wherein the introgression fragment comprises QTL7.1 (or a variant thereof).

[0233] Also provided is the use of chromosome 7 found in the seed deposited under accession number NCIMB44108 or its progeny to generate cultivated lettuce plants containing an introgression fragment of said chromosome 7.

[0234] Also provided is the use of a plant grown from the seed deposited under accession number NCIMB44108 or its progeny to generate a cultivated lettuce plant comprising Fol-4 and / or Fol-1 resistance, wherein the resistance is conferred by an introgression fragment obtained from chromosome 7 of the plant or progeny.

[0235] When referring to the presence of QTL7.1 in the deposited seed (NCIMB44108) or its progeny, it should be noted that the sequence flanking the SNP at nucleotide 101 shown in Table 2 is the flanking sequence of the particular donor used in mapping and introgression. However, the SNP marker at nucleotide 101 may also be present in a sequence that has less than 100% sequence identity to the sequence provided in SEQ ID NOS: 11-20, e.g., at nucleotide 101 of a sequence that has at least 95%, 96%, 97%, 98%, 99% sequence identity to the provided sequence. The sequence identity of the region flanking the SNP may be analyzed, for example, by BLAST analysis or by pairwise alignment of sequences of the same length that include the SNP at nucleotide 101 (e.g., using Needle with default parameters). Similarly, Table 1 shows SNPs at nucleotide 101 in sequences where the flanking sequences upstream and downstream of the SNP nucleotide are consensus sequences, taking into account variation in the flanking sequences between a particular L. serriola donor and an L. sativa reference genome. Thus, the SNP marker at nucleotide 101 of SEQ ID NOs: 1-10 can also be present in sequences that have less than 100% sequence identity to the sequences provided in SEQ ID NOs: 1-10, e.g., at nucleotide 101 of sequences that have at least 95%, 96%, 97%, 98%, 99% sequence identity to the provided sequences.

[0236] Similarly, the molecular marker sequences disclosed herein (and isolated nucleic acid molecules comprising such sequences), and The use of this molecular marker sequence in the detection and / or generation of lettuce plants containing the QTL described herein is encompassed herein.

[0237] Additionally, methods are provided for growing plants containing QTL7.1 (or variants thereof) in either fields, greenhouses, or tunnels in regions where Fusarium races Fol-4 and / or Fol-1 occur (e.g., Mediterranean countries (e.g., Spain, Italy, France) or Northern European countries (e.g., the Netherlands, Belgium, etc.)). Due to the presence of QTL7.1 in lettuce plants, less yield loss occurs during the growing season compared to plants lacking QTL7.1. Growing disease-resistant plants is the best way to control the effects of Fusarium wilt. When growing plants containing QTL7.1, there is less need for fallowing, sanitation procedures (e.g., removal of debris, cleaning of equipment, etc.), soil fumigation or solarization, crop rotation, and / or fungicide treatments.

[0238] In a further aspect, there is provided a method of transferring QTL7.1 from a Lactuca serriola plant into Lactuca sativa to generate a Fol-4 and / or Fol-1 resistant cultivated lettuce plant, comprising: a) crossing Lactuca serriola plants containing QTL7.1 with Lactuca sativa plants to generate an F1; b) optionally selfing this F1 one or more times to generate further selfed progeny; c) backcrossing this F1 or further selfed progeny one or more times to the Lactuca sativa plant of step a); and d) identifying and / or selecting backcross progeny that contain the genome of the Lactuca sativa plant of step a) that contains the introgression fragment of the Lactuca serriola plant of step a) on chromosome 7 containing QTL7.1. Including, The markers representing QTL7.1 are: - a guanine (G) for SNP_02 at nucleotide 101 of SEQ ID NO: 2 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 2, - a cytosine (C) for SNP_03 at nucleotide 101 of SEQ ID NO: 3 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 3, - an adenine (A) for SNP_04 at nucleotide 101 of SEQ ID NO: 4 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 4, - a guanine (G) for SNP_05 at nucleotide 101 of SEQ ID NO: 5 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 5, - a guanine (G) for SNP_06 at nucleotide 101 of SEQ ID NO: 6 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 6, - a thymine (T) for SNP_07 at nucleotide 101 of SEQ ID NO: 7 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 7, - a thymine (T) for SNP_08 at nucleotide 101 of SEQ ID NO: 8 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 8, - an adenine (A) for SNP_09 at nucleotide 101 of SEQ ID NO: 9 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 9 The method is provided in which the method is one, more, or all of:

[0239] In one aspect, the L. serriola plant of step a) is the plant from which a representative sample of seeds has been deposited under accession number NCIMB44108, or a progeny thereof obtained by selfing and / or crossing, which progeny comprises QTL7.1.

[0240] In a further aspect, there is provided a method of transferring QTL7.1 from one Lactuca sativa plant to another Lactuca sativa plant to generate a Fol-4 and / or Fol-1 resistant cultivated lettuce plant, comprising: a) crossing a first Lactuca sativa plant containing QTL7.1 with another second Lactuca sativa plant to produce an F1; b) collecting F1 seed from the cross and optionally selfing the F1 plants one or more times to generate an F2 or F3 population, or further selfed populations; c) optionally backcrossing the F1 plant, or an F2 or F3 plant, or a further selfed plant, to a second L. sativa plant to create a backcross population; d) optionally selfing this backcross population one or more times; and e) Identifying F1 plants, F2 plants, F3 plants, further selfed plants, or backcross plants containing one, more, or all of the SNP markers that represent QTL7.1. Including, The markers representing QTL7.1 are: - a guanine (G) for SNP_02 at nucleotide 101 of SEQ ID NO: 2 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 2, - a cytosine (C) for SNP_03 at nucleotide 101 of SEQ ID NO: 3 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 3, - an adenine (A) for SNP_04 at nucleotide 101 of SEQ ID NO: 4 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 4, - a guanine (G) for SNP_05 at nucleotide 101 of SEQ ID NO: 5 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 5, - a guanine (G) for SNP_06 at nucleotide 101 of SEQ ID NO: 6 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 6, - a thymine (T) for SNP_07 at nucleotide 101 of SEQ ID NO: 7 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 7, - a thymine (T) for SNP_08 at nucleotide 101 of SEQ ID NO: 8 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 8, - an adenine (A) for SNP_09 at nucleotide 101 of SEQ ID NO: 9 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 9 one, more, or all of A method is provided.

[0241] Also provided is a method for generating cultivated lettuce (Lactuca sativa) plants comprising Fol-4 and / or Fol-1 resistance, the method comprising: a) providing cultivated lettuce plants containing 1, 2, 3, 4, 5, 6, 7, 8 or more SNP markers indicative of QTL7.1; b) crossing cultivated lettuce plants with lettuce plants that are sensitive to Fol-4 and / or Fol-1 or contain only moderate resistance to Fol-4 and / or Fol-1 to produce F1 seeds; c) optionally selfing the plants grown from the F1 seeds one or more times to produce F2, F3, or further generations of selfed progeny; d) identifying F1, F2, F3, or further selfed progeny that have Fol-4 and / or Fol-1 resistance and / or contain an introgression fragment on chromosome 7 that contains QTL7.1; e) optionally crossing the identified F1 or further generation selfed progeny to the cultivated lettuce plant of step b) to produce backcross progeny; and f) optionally selecting backcross progeny comprising resistance to Fol-4 and / or Fol-1 and / or comprising an introgression fragment comprising QTL7.1 Including, The markers representing QTL7.1 in step a) are: - a guanine (G) for SNP_02 at nucleotide 101 of SEQ ID NO: 2 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 2, - a cytosine (C) for SNP_03 at nucleotide 101 of SEQ ID NO: 3 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 3, - an adenine (A) for SNP_04 at nucleotide 101 of SEQ ID NO: 4 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 4, - a guanine (G) for SNP_05 at nucleotide 101 of SEQ ID NO: 5 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 5, - a guanine (G) for SNP_06 at nucleotide 101 of SEQ ID NO: 6 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 6, - a thymine (T) for SNP_07 at nucleotide 101 of SEQ ID NO: 7 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 7, - a thymine (T) for SNP_08 at nucleotide 101 of SEQ ID NO: 8 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 8, - an adenine (A) for SNP_09 at nucleotide 101 of SEQ ID NO: 9 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 9 one, more, or all of It is a method.

[0242] In the above method, the susceptible L. sativa plant or a plant with moderate resistance to Fol-4 and / or Fol-1 is preferably a plant lacking QTL7.1. This plant may contain some level of resistance to Fusarium, but it is conferred by a different locus than QTL7.1. Therefore, QTL7.1 may be combined with other Fusarium resistance genes / loci found at different locations in the genome.

[0243] Furthermore, reference to a SNP marker indicative of QTL7.1 is understood to refer to the donor SNP haplotype (the nucleotides on one chromosome 7 in the plant) and / or donor SNP genotype (the nucleotides on both chromosomes 7 in the plant) of one, more than one, or all of the SNP markers provided herein that are linked to QTL7.1 (e.g., one or more of SNP_01 to SNP_10, preferably one or more of SNP_02 to SNP_09).

[0244] Deposit A total of 2500 seeds of Lactuca sativa homozygous and containing QTL7.1 from an L. serriola donor were deposited by Nunhems BV (Napoleonsweg 152, 6083 AB Nunhem, The Netherlands) under the Budapest Treaty on 1 February 2023 using Expert Solution at the depository NCIMB Limited, Wellheads Place, Dyce, Aberdeen, AB21 7GB, and were assigned the accession number NCIMB44108.

[0245] The deposited seeds do not meet the DUS references required to obtain plant variety protection and therefore cannot be considered a plant variety.

[0246] The applicant requests that samples of the biological material, and of any material derived therefrom, be released only to designated experts in accordance with Rule 32(1) EPC or the relevant legislation of any country or treaty having similar rules and regulations until the mention of the grant of the patent, or for a period of 20 years from the filing date if the application is refused, cancelled or deemed cancelled.

[0247] Access to this deposit will be available to any person the Director of Patents determines to be entitled thereto upon request during the pendency of this application. Subject to 37 C.FR § 1.808(b), all restrictions imposed by the depositor on the availability to the public of the deposit will be irrevocably removed upon the granting of a patent. This deposit will be maintained for 30 years, or 5 years from the most recent request, or for the enforceable life of the patent, whichever is longer, and will be replaced if it becomes nonviable during that period. Applicant does not waive any rights granted under this patent or under the Plant Variety Protection Act (7 U.S.C. 2321 et seq.) to this application.

[0248] The following non-limiting examples describe how plants containing QTL7.1 or variants thereof can be obtained. The examples provided herein are non-limiting examples. All patent and non-patent literature referred to herein is incorporated by reference.

[0249] Sequence data SEQ ID NO: 1: Consensus flanking sequence containing SNP_01 at nucleotide 101 together with the SNP nucleotides of the resistant donor SEQ ID NO: 2: Consensus flanking sequence containing SNP_02 at nucleotide 101 together with the SNP nucleotides of the resistant donor SEQ ID NO: 3: Consensus flanking sequence containing SNP_03 at nucleotide 101 together with the SNP nucleotides of the resistant donor SEQ ID NO: 4: Consensus flanking sequence containing SNP_04 at nucleotide 101 together with the SNP nucleotides of the resistant donor SEQ ID NO: 5: Consensus flanking sequence containing SNP_05 at nucleotide 101 together with the SNP nucleotides of the resistant donor SEQ ID NO: 6: Consensus flanking sequence containing SNP_06 at nucleotide 101 together with the SNP nucleotides of the resistant donor SEQ ID NO: 7: Consensus flanking sequence containing SNP_07 at nucleotide 101 together with the SNP nucleotides of the resistant donor SEQ ID NO: 8: Consensus flanking sequence containing SNP_08 at nucleotide 101 together with the SNP nucleotides of the resistant donor SEQ ID NO: 9: Consensus flanking sequence containing SNP_09 at nucleotide 101 together with the SNP nucleotides of the resistant donor SEQ ID NO: 10: Consensus flanking sequence containing SNP_10 at nucleotide 101 together with the SNP nucleotides of the resistant donor SEQ ID NO: 11: L. serriola donor flanking sequence containing SNP_01 at nucleotide 101, together with the SNP nucleotides of the resistant donor SEQ ID NO: 12: L. serriola donor flanking sequence containing SNP_02 at nucleotide 101 together with the SNP nucleotides of the resistant donor SEQ ID NO: 13: L. serriola donor flanking sequence containing SNP_03 at nucleotide 101, together with the SNP nucleotides of the resistant donor SEQ ID NO: 14: L. serriola donor flanking sequence containing SNP_04 at nucleotide 101, together with the SNP nucleotides of the resistant donor SEQ ID NO: 15: L. serriola donor flanking sequence containing SNP_05 at nucleotide 101, together with the SNP nucleotides of the resistant donor SEQ ID NO: 16: L. serriola donor flanking sequence containing SNP_06 at nucleotide 101, together with the SNP nucleotides of the resistant donor SEQ ID NO: 17: L. serriola donor flanking sequence containing SNP_07 at nucleotide 101, together with the SNP nucleotides of the resistant donor SEQ ID NO: 18: L. serriola donor flanking sequence containing SNP_08 at nucleotide 101, together with the SNP nucleotides of the resistant donor SEQ ID NO: 19: L. serriola donor flanking sequence containing SNP_09 at nucleotide 101, together with the SNP nucleotides of the resistant donor SEQ ID NO: 20: L. serriola donor flanking sequence containing SNP_10 at nucleotide 101, together with the SNP nucleotides of the resistant donor SEQ ID NO: 21: L. sativa reference genome V11 flanking sequence containing SNP_01 at nucleotide 101, together with the SNP nucleotides of the resistance donor SEQ ID NO: 22: L. sativa reference genome V11 flanking sequence containing SNP_02 at nucleotide 101, together with the SNP nucleotide of the resistance donor SEQ ID NO: 23: L. sativa reference genome V11 flanking sequence containing SNP_03 at nucleotide 101, together with the SNP nucleotide of the resistance donor SEQ ID NO: 24: L. sativa reference genome V11 flanking sequence containing SNP_04 at nucleotide 101, together with the SNP nucleotides of the resistance donor SEQ ID NO: 25: L. sativa reference genome V11 flanking sequence containing SNP_05 at nucleotide 101, together with the SNP nucleotide of the resistance donor SEQ ID NO: 26: L. sativa reference genome V11 flanking sequence containing SNP_06 at nucleotide 101, together with the SNP nucleotides of the resistance donor SEQ ID NO: 27: L. sativa reference genome V11 flanking sequence containing SNP_07 at nucleotide 101, together with the SNP nucleotide of the resistance donor SEQ ID NO: 28: L. sativa reference genome V11 flanking sequence containing SNP_08 at nucleotide 101, together with the SNP nucleotide of the resistance donor SEQ ID NO: 29: L. sativa reference genome V11 flanking sequence containing SNP_09 at nucleotide 101, together with the SNP nucleotide of the resistance donor SEQ ID NO: 30: L. sativa reference genome V11 flanking sequence containing SNP_10 at nucleotide 101, together with the SNP nucleotides of the resistance donor

[0250] In the consensus sequences of SEQ ID NO: 1 to SEQ ID NO: 10, differences in the regions flanking the SNP nucleotides are designated according to the IUPAC nucleotide ambiguity code, as shown below. RA or G YC or T SG or C WA or T KG or T MA or C BC or G or T DA or G or T HA or C or T VA or C or G N any base

[0251] Note that the differences between the L. serriola flanking sequence and the L. sativa reference genome V11 flanking sequence are small, with no differences found in the sequences flanking SNP_3, SNP_4, SNP_5, and SNP_7, one nucleotide difference found in the sequences flanking SNP_06 and SNP_08, two nucleotide differences found in the sequences flanking SNP_01 and SNP_02, five differences found in the sequence flanking SNP_10, and nine differences found in the sequence flanking SNP_09. Therefore, the greatest difference is found between SEQ ID NO: 09 (SNP_09 with L. serriola flanking sequence) and SEQ ID NO: 19 (SNP_09 with L. sativa reference genome V11 flanking sequence), which still share 95.5% sequence identity when aligned pairwise (using Emboss Needle). [Example]

[0252] A large in-house core set of germplasm consisting of Lactuca sativa, L. serriola, L. saligna, and L. virosa species was screened for resistance to Fusarium oxysporum lactucae races Fol-1 and Fol-4 in a high-throughput in vivo root assay.

[0253] This high-throughput screen identified an L. serriola donor line obtained from the Dutch CGN collection and originating from Georgia.

[0254] Through subsequent rescreening in resistance assays, this donor was confirmed to exhibit moderate to high levels of resistance to the Fol-1 and Fol-4 races of Fusarium oxysporum lactucae.

[0255] To map the underlying QTLs, segregating F2 mapping populations were generated by crossing the donor with elite susceptible cultivars, and the resulting F2 populations were subjected to QTL mapping (n = 184 for Fol-1 and Fol-4, respectively, in each screening).

[0256] Phenotypic data were generated according to our in-house routine in vivo protocol, and tissue samples from the corresponding plants were collected to generate genotypic data using the infinium XT genotyping platform, which contains 18K markers. Among these, approximately 2000 markers were found to be informative and provided good genome coverage with good distribution in this particular mapping population. Using IM analysis, we identified major QTLs that confer moderate levels of resistance to races Fol-1 and Fol-4.

[0257] The QTL was finely mapped to the region beginning with SNP_01 at nucleotide 64.382.881 (SNP_01) on chromosome 7 of the reference genome V11 and ending with SNP_10 at nucleotide 69.375.685 (SNP_10) on chromosome 7 of this reference genome V11. Therefore, SNP_01 and SNP_10 are markers flanking the region containing QTL7.1. The L. sativa V11 reference genome can be found on the World Wide Web at ncbi.nlm.nih.gov / data-hub / genome / ?taxon=4236, and BLAST can be performed with any of the sequences provided herein to identify the nucleotide location of the SNP on chromosome 7 of this V11 reference genome. This genome is also referred to as Lactuca sativa cultivar Salinas (LSAT_Salinas_v11).

[0258] The genomic region containing QTL7.1 from the L. serriola donor is characterized by the presence of QTL7.1 and one or more of the following SNP markers linked to QTL7.1 as shown in the table below:

[0259] Table 1 shows the consensus sequence flanking the SNP, taking into account the nucleotide differences (in the sequence region flanking the SNP nucleotide) between the wild L. serriola donor (shown in Table 2) and the L. sativa reference genome (shown in Table 3). So, for example, a "C" in the wild donor and an "A" in the L. sativa V11 reference genome are shown as "M" in this consensus sequence. This consensus sequence is based on the IUPAC nucleotide code.

[0260] An example of the BLAST output of SEQ ID NO:1 (query) against Lsat_Salinas_v11 is shown in Figure 3, where the "query" sequence is aligned with the "subject" chromosome 7 sequence of the L. sativa V11 genome. The SNP at nucleotide 101 of SEQ ID NO:1 is located at nucleotide 64,382,881 of chromosome 7 of the L. sativa V11 genome. Both sequences have 99% sequence identity in the BLAST output (not shown).

[0261] [Table 1]

[0262] [Table 2]

[0263] [Table 3]

[0264] [Table 4]

[0265] [Table 5]

[0266] [Table 6]

[0267] [Table 7]

[0268] [Table 8]

[0269] [Table 9]

[0270] [Table 10]

[0271] [Table 11]

[0272] [Table 12]

[0273] [Table 13]

[0274] The resistance donor nucleotides for SNP markers SNP_02, SNP_03, SNP_04, SNP_05, SNP_06, SNP_08, and SNP_09 appear to be unique to the particular wild L. serriola accession used for mapping and introgression of QTL7.1.

[0275] From the mapping population, an L. sativa line homozygous for the introgression fragment containing QTL7.1 was selected, and seeds resulting from this line were deposited by Nunhems BV under the Budapest Treaty and assigned the accession number NCIMB44108.

[0276] The L. serriola donor and L. sativa lines containing the QTL7.1 introgression (seed deposit NCIMB44108) were further tested with a differential set of ISFs in root dip assays (see the World Wide Web at worldseed.org / our-work / disease-resistance / differential-hosts / ) as described in the CPVO protocol (on the World Wide Web at cpvo.europa.eu, pages 34 to 36).

[0277] Briefly, nine plants per genotype were tested with either Fol-1 (reference isolate from Naktuinbouw) or Fol-4 (isolate 04750888 from Gilardi et al. 2017).

[0278] Before transplanting, the roots of young plants are soaked in water for 5-15 minutes. 6 The seeds were suspended in a spore suspension containing spores / ml.

[0279] 18 days after inoculation, the CPVO scale for "inoculation by soaking seedlings" (see page 35 of the CPVO protocol with photographs): 0: Plants without symptoms and healthy vessels 1: Plants with brown vessels only under the cotyledons, no yellowing or wilting 2: Plants with brown vessels above the cotyledons and no yellowing or wilting 3: Yellowing and wilting plants with brown vessels 4: Plant death Phenotypic observations were performed using

[0280] The photographs in Figures 1 and 2 were taken 12 days after inoculation.

[0281] The results are shown in Table 4 below.

[0282] [Table 14]

Claims

1. 1. Lettuce plants (Lactuca sativa L.) comprising a quantitative trait locus (QTL) designated QTL7.1 from Lactuca seriola that confers resistance to Fusarium oxysporum lactucae speciale races Fol-1 and Fol-4, said QTL7.1 being located on chromosome 7 between nucleotide 64.382.881 (SNP_01 at nucleotide 101 of SEQ ID NO:1) and nucleotide 69.375.685 (SNP_10 at nucleotide 101 of SEQ ID NO:10), and a representative sample of which is identified under accession number NCIMB A lettuce plant, as found in the genome of a plant grown from seed deposited under No. 44108.

2. 2. The lettuce plant of claim 1, wherein the plant comprises a thymine (T) for SNP_07 at nucleotide 101 of SEQ ID NO:7 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO:

7.

3. The plant may have in its genome the following groups: - a guanine (G) for SNP_02 at nucleotide 101 of SEQ ID NO:2 or at the equivalent nucleotide of a sequence containing at least 95% sequence identity to SEQ ID NO:2; - a cytosine (C) for SNP_03 at nucleotide 101 of SEQ ID NO: 3 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 3; - an adenine (A) for SNP_04 at nucleotide 101 of SEQ ID NO: 4 or at the equivalent nucleotide of a sequence containing at least 95% sequence identity to SEQ ID NO: 4; - a guanine (G) for SNP_05 at nucleotide 101 of SEQ ID NO: 5 or at the equivalent nucleotide of a sequence containing at least 95% sequence identity to SEQ ID NO: 5; - a guanine (G) for SNP_06 at nucleotide 101 of SEQ ID NO: 6 or at the equivalent nucleotide of a sequence containing at least 95% sequence identity to SEQ ID NO: 6; - a thymine (T) for SNP_07 at nucleotide 101 of SEQ ID NO: 7 or at the equivalent nucleotide of a sequence containing at least 95% sequence identity to SEQ ID NO: 7; - a thymine (T) for SNP_08 at nucleotide 101 of SEQ ID NO: 8 or at the equivalent nucleotide of a sequence containing at least 95% sequence identity to SEQ ID NO: 8; - an adenine (A) for SNP_09 at nucleotide 101 of SEQ ID NO:9 or at the equivalent nucleotide of a sequence containing at least 95% sequence identity to SEQ ID NO:9 3. The lettuce plant (Lactuca sativa L.) according to claim 1 or 2, comprising at least 2, 3, 4, 5, 6, 7, or 8 markers selected from:

4. A lettuce plant (Lactuca sativa L.) according to any one of claims 1 to 3, wherein the plant comprises QTL7.1 in homozygous form.

5. A seed capable of growing into a lettuce plant according to any one of claims 1 to 4.

6. 5. A seed produced from the lettuce plant of any one of claims 1 to 4, comprising QTL7.

1.

7. A progeny plant of the lettuce plant of any one of claims 1 to 4, comprising QTL7.

1.

8. 5. Propagation material derived from a plant according to any one of claims 1 to 4, comprising said QTL7.

1.

9. Propagation material according to claim 8, capable of growing into a plant according to any one of claims 1 to 4.

10. 1. A method for detecting or selecting a plant, plant part, or seed containing QTL7.1, comprising detecting or selecting the following SNP markers in the genome of said plant, plant part, or seed: - a guanine (G) for SNP_02 at nucleotide 101 of SEQ ID NO:2 or at the equivalent nucleotide of a sequence containing at least 95% sequence identity to SEQ ID NO:2; - a cytosine (C) for SNP_03 at nucleotide 101 of SEQ ID NO: 3 or at the equivalent nucleotide of a sequence comprising at least 95% sequence identity to SEQ ID NO: 3; - an adenine (A) for SNP_04 at nucleotide 101 of SEQ ID NO: 4 or at the equivalent nucleotide of a sequence containing at least 95% sequence identity to SEQ ID NO: 4; - a guanine (G) for SNP_05 at nucleotide 101 of SEQ ID NO: 5 or at the equivalent nucleotide of a sequence containing at least 95% sequence identity to SEQ ID NO: 5; - a guanine (G) for SNP_06 at nucleotide 101 of SEQ ID NO: 6 or at the equivalent nucleotide of a sequence containing at least 95% sequence identity to SEQ ID NO: 6; - a thymine (T) for SNP_07 at nucleotide 101 of SEQ ID NO: 7 or at the equivalent nucleotide of a sequence containing at least 95% sequence identity to SEQ ID NO: 7; - a thymine (T) for SNP_08 at nucleotide 101 of SEQ ID NO: 8 or at the equivalent nucleotide of a sequence containing at least 95% sequence identity to SEQ ID NO: 8; - an adenine (A) for SNP_09 at nucleotide 101 of SEQ ID NO:9 or at the equivalent nucleotide of a sequence containing at least 95% sequence identity to SEQ ID NO:9 determining the presence of at least 2, 3, 4, 5, 6, 7, or 8 of: and optionally selecting a plant, or plant part, or seed containing said SNP marker. A method comprising:

11. 11. The method of claim 10, - testing said plants or seeds comprising said at least 2, 3, 4, 5, 6, 7 or 8 SNP markers for resistance to Fusarium races Fol-4 and / or Fol-1, and optionally selecting said plants or seeds comprising resistance to Fusarium races Fol-4 and / or Fol-1. The method further comprises:

Images