Molecular marker related to leukoderma resistance on corn chromosome 8 and application of molecular marker

Abstract

The invention belongs to the technical field of molecular marker-assisted breeding, and particularly relates to a molecular marker related to leukoderma resistance on a corn No.8 chromosome and application of the molecular marker, the gene sequence of the molecular marker located on the corn No.8 chromosome is shown as SEQ ID NO: 1 and / or SEQ ID NO: 2, the molecular marker is jointly located to SNP: 8-149153434 and a related gene Zm00001eb358700 (SEQ ID NO: 2) on the corn No.8 chromosome through many-year multi-point experiments, and the molecular marker is used for identifying the leukoderma resistance of the corn No.8 chromosome. The SNP can be positioned in a plurality of different environments, 22.5% of phenotypic variation can be explained, and the highest dominant effect is achieved; the associated candidate functional gene mainly encodes a heat stress transcription factor C-1a of an HSF family and is proved to be related to corn resistance, and the locus can be used as a corn leukoderma resistance molecular marker.

Description

Technical Field

[0001] The invention belongs to the technical field of molecular marker-assisted breeding, and specifically relates to an application of a molecular marker site SNP:8-149153434 related to white spot disease resistance on corn chromosome 8 and a candidate functional gene Zm00001eb358700 associated therewith in improving corn white spot disease resistance. Prior art

[0002] As one of the important food crops, corn (Zea mays L.) directly affects the world's food security and the development of animal husbandry. In recent years, corn white spot disease caused by Pantoea ananatis is a leaf disease that seriously affects corn production. The disease was first reported in India in 1965 and was prevalent in Brazil and the United States from the 1980s to the 1990s. According to reports, severe white spot disease can cause a more than 60% reduction in corn production in Brazil. Since mid-July 2020, white spot disease has broken out in the southwestern corn ecological zone of my country, especially in Yunnan, resulting in a large-scale reduction in corn production in some areas, with losses of 10% to 50%, seriously endangering corn production and causing a sharp drop in farmers' income. Since 2023, the disease has spread to the main corn producing areas in the north and has now become a national corn disease. In the early stage of corn white spot disease, lesions appear on the leaves at the base, and then quickly spread to the upper part of the plant. In the later stages of the disease, a chlorotic appearance appears, which affects the plant carbon cycle and photosynthesis. If some leaves are infected before the corn filling stage, the net photosynthetic rate can drop sharply by 40%, which will cause the reproductive maturity stage to end prematurely, and ultimately lead to deformed corn ears and low seed yield, seriously reducing the yield and quality of corn.

[0003] At present, the prevention and control of white spot disease mainly focuses on measures such as optimizing field farming systems and the use of agricultural chemicals. Studies in recent years have shown that white spot disease resistance depends largely on its genetic factors. Therefore, genetically cultivating white spot disease-resistant varieties is the most economical and effective way to control the disease. However, since white spot disease is a newly erupted corn disease in my country, functional genes related to white spot disease resistance have not yet been cloned. Based on whole genome association analysis and QTL positioning, the present invention uses tropical corn inbred lines (YML32, TRL418, CML171, TML139, YML226, NK40-1) as resistant parents, hybridizes with temperate susceptible excellent inbred line Ye107, and selects 6 F9 recombinant inbred lines (RIL) after 9 consecutive generations of single-grain self-pollination. These RILs were planted in Yanshan County, Yunnan Province for three consecutive years to carry out corn white spot disease resistance phenotypic identification. Combined with the high-quality SNPs of the RIL population, the resistance SNP molecular markers and functional genes significantly associated with corn white spot disease resistance were identified through GWAS analysis. Summary of the invention

[0004] The main purpose of the present invention is to provide a molecular marker site SNP: 8-149153434 related to white spot disease resistance on corn chromosome 8 and the application of the candidate functional gene Zm00001eb358700 associated therewith in improving the resistance to white spot disease of corn. Specifically, the present invention provides the following technical solutions:

[0005] In one aspect, the present invention provides molecular markers associated with corn white spot resistance, wherein the molecular marker gene sequence is shown in SEQ ID NO:1 and / or SEQ ID NO:2.

[0006] Furthermore, the molecular marker, as shown in SEQ ID NO:1, presents T / A polymorphism at the 201st base from the 5′ end; as shown in SEQ ID NO:2, the sequence corresponds to corn Chr8:149156241-149158195 sequence, and presents A / T polymorphism at the 149156930th base from the 5′ end, and as shown in SEQ ID NO:2, the expression level of the gene or its translated protein is positively correlated with corn white spot resistance.

[0007] On the other hand, the present invention provides molecular markers associated with resistance to corn white spot disease, wherein the molecular markers are SNP sites, including at least one of sites 149153434, 149156506, 149157812, 149157853, 149157932, 149157959 or 149156930 located on chromosome 8 of corn, and the reference genome version where the SNP site is located is Zm-B73-REFERENCE-NAM-5.0.

[0008] Furthermore, the present invention provides any of the following applications of any of the molecular markers:

[0009] a) Genetic diversity analysis of maize resistant to white spot disease; b) Construction of molecular genetic map of maize resistant to white spot disease; c) Whole genome association analysis of maize resistant to white spot disease; d) Identification of maize varieties resistant to white spot disease; e) Molecular marker-assisted selection breeding of maize resistant to white spot disease; f) Whole genome selection breeding of maize resistant to white spot disease.

[0010] In another aspect, the present invention provides a product for detecting any of the molecular markers, the product comprising a reagent, a kit or a gene chip, the product detecting the genotype of the molecular marker, or detecting the expression level of the sequence shown in SEQ ID NO: 2 or its translated protein. In some embodiments, the gene chip comprises a liquid chip or a solid chip; in some more specific embodiments, the kit comprises a nucleic acid extraction and purification reagent: used to extract DNA from a sample, such as a lysis solution, a deproteinization solution, a rinse solution, etc.; a PCR reaction reagent: including primers, probes, dNTPs (deoxynucleotide triphosphates), DNA polymerase, etc. for amplifying specific genes; a fluorescently labeled probe: in fluorescent PCR technology, a fluorescently labeled probe used for real-time detection of gene mutations, etc.

[0011] In another aspect, the present invention provides a product for detecting any of the molecular markers, including a product prepared by PCR, qPCR, Sanger sequencing, high-throughput sequencing, fluorescence in situ hybridization, TaqMan probe method, ARMS-PCR method or KASP method, and the product detects the genotype of the molecular marker, or detects the expression level of the sequence shown in SEQ ID NO: 2 or its translated protein.

[0012] Furthermore, the present invention provides any of the following applications of the product:

[0013] a) Genetic diversity analysis of white spot disease resistant maize; b) Construction of molecular genetic map of white spot disease resistant maize; c) Whole genome association analysis of white spot disease resistant maize; d) Identification or auxiliary identification of white spot disease resistant maize varieties; e) Molecular marker-assisted selection breeding of white spot disease resistant maize; f) Whole genome selection breeding of white spot disease resistant maize.

[0014] On the other hand, the present invention provides a method for screening corn with resistance to white spot disease. A corn sample to be tested is taken, and the gene sequence shown in SEQ ID NO:1 is detected. When the base at the 201st position from the 5′ end of the sequence shown in SEQ ID NO:1 is A, a corn variety with resistance to white spot disease is obtained.

[0015] On the other hand, the present invention provides a method for screening corn with resistance to white spot disease. A corn sample to be tested is taken, and the expression level or genotype of the gene sequence shown in SEQ ID NO:2 is detected. When the sequence shown in SEQ ID NO:2 or its translated protein is overexpressed and / or the base at the 149156930th position from the 5′ end is T, a corn variety with resistance to white spot disease is obtained. The expression level of the gene shown in SEQ ID NO:2 or its translated protein is positively correlated with the resistance to corn white spot disease.

[0016] On the other hand, the present invention provides a method for screening corn with white spot disease resistance, taking a corn sample to be tested, detecting SNP sites, the SNP sites include at least one of 149153434, 149156506, 149157812, 149157853, 149157932, 149157959 or 149156930 sites on chromosome 8 of corn, the reference genome version of the SNP site is Zm-B73-REFERENCE-NAM-5.0, when the bases of the SNP site are A, C, C, A, C, C and T respectively, it is judged as a corn variety with white spot disease resistance. In a specific embodiment, the SNP sites provided by the present invention are used to prepare a liquid gene chip, and multiple site detections are performed by high-throughput genotype detection technology to identify or assist in identifying corn white spot disease resistance.

[0017] The technical effects achieved by the present invention are:

[0018] Through multi-point experiments over many years, the present invention co-localized SNP: 8-149153434 and its associated gene Zm00001eb358700 (Chr8: 149156241-149158195, NCBI gene ID number: 103636099) on chromosome 8 of maize. The SNP can be located in multiple different environments, can explain 22.5% of the phenotypic variation, and has the highest dominant effect; its associated candidate functional gene mainly encodes the heat stress transcription factor C-1a of the HSF family, which has been confirmed to be related to maize resistance. The site can be used as a molecular marker for maize white spot resistance.

[0019] The present invention confirms through research that SNP: 8-149153434 of corn chromosome 8 and its associated gene Zm00001eb358700 have strong resistance to corn white spot disease. Corn white spot disease resistance is a quantitative trait regulated by multiple genes. The technical solution provided by the present invention provides a new method for breeding new corn varieties resistant to white spot disease using modern molecular breeding technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Leaf images of corn with different grades of white spot disease; HR: highly resistant to white spot disease, R: resistant to white spot disease, M: moderately resistant to white spot disease, S: sensitive to white spot disease, HS: highly susceptible to white spot disease.

[0021] Figure 2 .Correlation heat map of white spot disease resistance in six populations; describes the correlation of the overall performance of the six RIL populations under different environments. The narrower the circle and the redder the color, the stronger the correlation.

[0022] Figure 3. SNP density and LD decay plots; (a) Chromosome-specific SNP density within 1Mb intervals, the ordinate represents the chromosome, the abscissa represents the position on each chromosome, and the redder the corresponding position, the more variant sites there are. (b) The change of genome-wide LD decay (r2) of all chromosomes in 941 maize RILs with physical distance (Kb).

[0023] Figure 4 Manhattan plot and QQ plot; Manhattan plot (left) and QQ plot (right) of YS21 (a), YS22 (b), YS23 (c), BLUP (d) show SNPs associated with MWS resistance. Each point in the left figure represents a SNP, and the black line represents the threshold of <1×10-5. Different colors represent different chromosomes. The red line in the right figure is the trend line that the ideal QQ plot should correspond to in each case.

[0024] Figure 5 . Box plots of SNP additive and dominant properties;

[0025] Figure 6 .Identification diagram of the candidate gene Zm00001eb358700 for white spot disease resistance; (a) LD block of the candidate gene; (b) Schematic diagram of the mutation sites that form different haplotypes in the Zm00001eb358700 gene.

[0026] Figure 7 . Overall difference of seven haplotypes in resistance to corn white spot disease, * indicates p<0.05, **** indicates p<0.0001;

[0027] Figure 8 . (a) The relative position of Zm00001eb358700 and SNP, and the base variation and amino acid variation diagram in the parent TML139; (b) The expression level diagram of the Zm00001eb358700 gene in different tissues of corn at different stages. The red boxes are leaves at different stages, and it can be seen that its expression level is high in the leaves of corn at different stages. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] The invention is based on whole genome association analysis, uses tropical maize inbred lines (YML32, TRL418, CML171, TML139, YML226, NK40-1) as resistant parents, hybridizes with temperate susceptible excellent inbred line Ye107, and selects 6 F9 recombinant inbred lines (RIL) after 9 consecutive generations of single seed self-pollination. These RILs were planted in Yanshan County, Yunnan Province for three consecutive years to carry out phenotypic identification of white spot disease resistance. Combined with the high-quality SNPs of the RIL population, GWAS analysis identified molecular marker SNPs that were significantly associated with corn white spot disease resistance in multiple environments: 8-149153434 (i.e., the 201bp site from the 5′ end of the sequence shown in SEQ ID NO: 1) and its associated gene Zm00001eb358700 (Chr8: 149156241-149158195, NCBI gene ID number: 103636099). Molecular breeding can be used to apply this resistance gene to corn white spot disease resistance breeding in the future.

[0030] The utility of the molecular markers provided by the present invention is fully explained through the following examples:

[0031] Example 1

[0032] 1. Experimental methods

[0033] 1. Experimental Materials and Design

[0034] In this experiment, six tropical maize inbred lines (YML32, TRL418, CML171, TML139, YML226, and NK40-1) with wide genetic variation and resistance to white spot disease were selected as female parents, and Ye107, an excellent temperate maize inbred line susceptible to white spot disease, was used as a common parent for hybridization (the pedigree, heterotic groups, ecological groups, and related resistance levels of the seven parents are detailed in Table 1). Through the single-seed transmission method, nine consecutive generations of self-pollination were performed to produce six recombinant inbred line (RIL) populations: pop1 (YML32×Ye107), pop2 (TRL418× The RIL lines were selected from the following 100 RIL lines: Ye107, pop3 (CML171×Ye107), pop4 (TML139×Ye107), pop5 (YML226×Ye107), and pop6 (NK40-1×Ye107). Initially, each population contained 200 RIL lines, but due to environmental selection, inbreeding depression, and other factors, 904 RIL lines were finally available for this study (pop1: 145; pop2: 141; pop3: 147; pop4: 160; pop5: 152; pop6: 159). These RIL lines were planted in Yanshan County, Yunnan Province (23°19'-23°59'N, 103°35'-104°45'E) in 2021, 2022, and 2023. The experimental design adopted a completely randomized block design, with 14 plants per row, a row length of 4 m, and a plant spacing of 25 cm. Standard farmland management was followed.

[0035] Table 1. Pedigrees, ecotypes and white spot resistance of the seven parents used in the experiment

[0036]

[0037]

[0038] 2. Disease grade score

[0039] The white spot disease resistance phenotype of RILs from a multi-parent population was evaluated in Yanshan County (YS), Yunnan Province, China in 2021, 2022, and 2023. Maize white spot disease outbreaks occur from early August to late September each year, when maize is in the grain filling to maturity stage, which is suitable for resistance assessment. The disease severity grading of white spot disease follows the symptom recognition criteria outlined in the Maize Disease and Pest Manual, and the average disease severity of a single plot is evaluated on a scale of 1 to 9, such as Figure 1 , as shown in Table 2.

[0040] Table 2. Classification standards for corn white spot disease

[0041]

[0042] 3. Phenotypic Identification and Statistical Analysis

[0043] Descriptive analyses of phenotypic data were performed using SPSS (SPSS Statistics) and ORIGIN (Origin 2022) software. Mean, minimum, maximum, standard deviation (SD), coefficient of variation (CV), skewness, and kurtosis were calculated. Frequency distribution of phenotypic data was performed using SPSS software. Kurtosis and skewness were used to assess the normality of the frequency distribution. Broad-sense heritability was calculated following the method outlined by Knapp et al.

[0044] 4. Whole-genome resequencing

[0045] DNA was extracted from maize seedling leaves using a modified CTAB method and subjected to whole-genome resequencing. DNA libraries were prepared according to standard procedures and sequenced using Illumina Hi Seq TM The filtered reads were then aligned to the maize reference genome B73_RefGen_v5 (full name: Zm-B73-REFERENCE-NAM-5.0) to identify SNP markers, which were annotated using SNPeff software.

[0046] 5. Population structure analysis and LD decay

[0047] The distance matrix was calculated using TreeBeST (version: Treebest-1.9.2) software, and the phylogenetic tree was constructed based on this distance matrix using the neighbor-joining method (NJ). To ensure accuracy, the bootstrap values ​​were calculated up to 1000 times. PCA analysis was performed using GCTA. After obtaining the PCA results, the values ​​of the first two PCs were used to display the samples involved in the analysis in two dimensions. PopLDdecay software was used to calculate the degree of linkage disequilibrium (r 2 ) and used the software's own script Plot_OnePop.pl to plot LD decay.

[0048] 6. Genome-wide association analysis

[0049] A genome-wide association analysis was performed using GEMMA software (http: / / www.xzlab.org / software.html) based on 6,390,967 high-quality SNP analyses. The analysis used a mixed linear model (MLM) for GWAS for phenotypes and best linear unbiased estimates (BLUPs) for all environments. A significance threshold of -log10(p)>5 was used to identify significant SNPs associated with corn white spot resistance, and bedtools v1.7 was used to extract SNP sites that met or exceeded the threshold. Based on the B73_RefGen_v5 reference genome and annotation information, candidate genes associated with corn white spot resistance were screened within 50 kb upstream and downstream of the significant SNPs.

[0050] 7. Analysis of additive and dominant effects of resistance-related SNP loci

[0051] Mixed linear model (MLM) analysis was performed using Tassel software, and corrections were made using kinship and PCA matrices to calculate the additive and dominant effects of SNPs.

[0052] 8. Candidate Gene Analysis

[0053] Haploview v4.2 software was used to perform haplotype analysis of candidate genes. The corresponding gene sequences were extracted from the reference genome B73_RefGen_v5 according to the candidate gene IDs and compared with the parent with the strongest resistance, TML139. The corresponding coding regions and amino acid variation information were extracted, and the functional gene motifs were predicted using MEME online software (https: / / meme-suite.org / meme / tools / meme).

[0054] (II) Experimental results

[0055] 1. Phenotypic Data Analysis

[0056] The white spot disease resistance phenotypic data of six RIL groups in Yanshan were collected for three years, and descriptive statistical analysis was performed. The results showed that the coefficient of variation of the six RIL groups in Yanshan was between 0.25-0.79, indicating that there were differences between the samples. At the same time, the average disease level of white spot disease in plants of the six RIL groups was between 2.90-5.81, and the absolute values ​​of the skewness and kurtosis coefficients of the six groups in three years were close to 1, indicating that the white spot disease resistance phenotypes of the test groups in the three-year resistance identification were in line with the normal distribution and met the quantitative trait characteristics. Further analysis showed that the heritability of the severity of white spot disease in each RIL group ranged from 76.47% to 98.79%, and there was a strong correlation between the resistance phenotypes of the same group under different environments (0.46-0.98) ( Figure 2), indicating that the RIL lines have strong consistency in resistance to white spot disease in different environments. The phenotypic identification results show that corn white spot disease resistance has a high heritability and corn white spot disease resistance is mainly determined by genes.

[0057] 2SNP density and LD decay

[0058] Through whole genome resequencing, a total of 6,390,967 high-quality SNPs were identified in the whole genome. These SNPs were evenly distributed on the 10 chromosomes of maize ( Figure 3 a) The number of SNPs identified on chromosomes 1 to 10 are as follows: 1354402, 699661, 716354, 880880, 668865, 485243, 563392, 545220, 472482, and 462679. A total of 6390967 SNPs were identified to assess linkage disequilibrium (LD) decay in the association mapping population. Figure 3 As shown in b, when r 2 When the decline rate tends to be flat, the physical distance is about 50kb. Therefore, we selected the 50kb range upstream and downstream of the significant SNP site as the standard for screening candidate genes.

[0059] 3. Group structure analysis

[0060] We used TreeBeST to analyze the population phylogenetic tree and divided the 941 RIL lines into 6 subgroups. We then used GCTA to perform principal component analysis (PCA), which also divided the 941 RIL lines into 6 subgroups, which were consistent with the 6 RIL populations we assembled. During the analysis, some mixed or overlapping families were found, which may be due to the common parent Ye107 in the 6 subgroups and the gene introgression during the breeding process. Therefore, the possibility that the population structure will lead to false positives in GWAS needs to be considered in subsequent analysis.

[0061] 4. Genome-wide association analysis

[0062] The software GEMMA (http: / / www.xzlab.org / software.html) was used to conduct GWAS analysis on the white spot disease resistance phenotype data of 941 RIL lines in the multi-parent population in the three years of Yanshan and 6390967 high-quality SNPs obtained by whole genome resequencing. The mixed linear model (MLM) was used to simultaneously correct for population structure and individual kinship, and multiple SNPs were identified. Since artificial populations may cause false positives in GWAS analysis results, it is necessary to cross-validate SNPs using multiple results in multiple environments. By comparing the GWAS analysis results of Yanshan for three years, a total of multiple consistent significant SNPs that co-localized in all environments were identified ( Figure 4 ), the present invention conducted additive effect and dominant effect analysis on four co-located SNP loci with large effect values ​​related to corn white spot disease resistance, and found that the SNP with the largest phenotypic contribution rate: 8-149153434 has the largest dominant effect ( Figure 5 ), indicating that this SNP has a significant effect on improving corn white spot disease resistance.

[0063] 5. Candidate gene mining

[0064] This study used the B73_RefGen_v5 reference genome to screen the 50Kb region upstream and downstream of SNP: 8-149153434 with the largest effect value and the largest dominant effect, and used databases such as MaizeGDB, InterPro, UniProt and NCBI to annotate and predict the function of candidate genes. Finally, the candidate functional gene Zm00001eb358700 associated with SNP: 8-149153434 located on chromosome 8 was screened. SNP: 8-149153434 and gene Zm00001eb358700 were co-located in 21YS, 22YS, 23YS, and BLUP. The SNP explained a total of 22.5% of the phenotypic variation and had the largest dominant effect among the four significant SNPs with the highest effect values ​​( Figure 5 , Figure 6 a), indicating that the SNP has a strong effect on white spot disease resistance. The Zm00001eb358700 gene mainly encodes the heat stress transcription factor C-1a of the HSF family. HSF transcription factors regulate the expression of jasmonic acid, abscisic acid, indole-3-acetic acid and other plant hormones, which mediate the activation of stress conditions under certain conditions to enhance the stress tolerance of plants.

[0065] 6. Candidate Gene Analysis

[0066] In order to clarify whether the selected candidate functional gene Zm00001eb358700 is related to the resistance to corn white spot disease, Zm00001eb358700 was analyzed and it was found that Zm00001eb358700 mutated at sites 149156506, 149157812, 149157853, 149157932 and 149157959 on chromosome 8 of corn, making the gene Zm00001eb358700 show 7 major haplotypes: CCGAT (Hap1), TTGAT (Hap2), TCACC (Hap3), CCACC (Hap4), CTGAT (Hap5), CTGCT (Hap6) and TTGCT (Hap7). Among them, plants with haplotype CCACC (Hap4) showed better resistance to corn white spot disease ( Figure 6b. Figure 7 ). By comparing the sequence of this gene in the resistant material TML139, a specific A / T mutation was found at position 149156930 of the Zm00001eb358700 gene of TML139, which caused the corresponding amino acid sequence of the resistant material TML139 to mutate from threonine to serine ( Figure 8 a), the mutation of these amino acids changes the motif of the protein. By studying the expression of the gene RNA in different periods and different tissues of corn, it was found that Zm00001eb358700 in leaves remained at a high level ( Figure 8 b), further proving that this gene is closely related to resistance to maize leaf diseases.

[0067] Although the present invention has been described in detail above with general descriptions and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements may be made thereto based on the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection claimed by the present invention.

Claims

1. A molecular marker associated with corn white spot disease resistance, characterized in that: The molecular marker gene sequence is shown in SEQ ID NO: 1 and / or SEQ ID NO:

2.

2. The molecular marker according to claim 1, characterized in that As shown in SEQ ID NO:1, the base at the 201st position from the 5′ end presents a T / A polymorphism; as shown in SEQ ID NO:2, the sequence corresponds to the corn Chr8:149156241-149158195 sequence, and the base at the 149156930th position from the 5′ end presents an A / T polymorphism, or as shown in SEQ ID NO:2, the expression level of the gene or its translated protein is positively correlated with the resistance to corn white spot disease.

3. A molecular marker associated with corn white spot disease resistance, characterized in that: The molecular markers are SNP sites, including at least one of sites 149153434, 149156506, 149157812, 149157853, 149157932, 149157959 or 149156930 located on chromosome 8 of corn, and the reference genome version where the SNP sites are located is Zm-B73-REFERENCE-NAM-5.

0.

4. Any of the following uses of the molecular marker according to any one of claims 1 to 3, a) Genetic diversity analysis of maize resistant to white spot disease; b) Construction of molecular genetic map of maize resistant to white spot disease; c) Whole genome association analysis of maize resistant to white spot disease; d) Identification of maize varieties resistant to white spot disease; e) Molecular marker-assisted selection breeding of maize resistant to white spot disease; f) Whole genome selection breeding of maize resistant to white spot disease.

5. A method for detecting a product labeled with a molecule according to any one of claims 1 to 3, characterized in that: The product includes a reagent, a kit or a gene chip, and the product detects the genotype of the molecular marker, or detects the expression level of the sequence shown in SEQ ID NO: 2 or its translated protein.

6. A method for detecting a product labeled with a molecule according to any one of claims 1 to 3, characterized in that: The products include products prepared by PCR, qPCR, Sanger sequencing, high-throughput sequencing, fluorescence in situ hybridization, TaqMan probe method, ARMS-PCR method or KASP method, and the products detect the genotype of the molecular marker, or detect the expression level of the sequence shown in SEQ ID NO: 2 or its translated protein.

7. Any of the following uses of the product according to claim 5 or 6, a) Genetic diversity analysis of white spot disease resistant maize; b) Construction of molecular genetic map of white spot disease resistant maize; c) Whole genome association analysis of white spot disease resistant maize; d) Identification or auxiliary identification of white spot disease resistant maize varieties; e) Molecular marker-assisted selection breeding of white spot disease resistant maize; f) Whole genome selection breeding of white spot disease resistant maize.

8. A method for screening corn resistant to white spot disease, characterized in that: A corn sample to be tested is taken, and the gene sequence shown in SEQ ID NO: 1 is tested. When the base at the 201st position from the 5′ end of the sequence shown in SEQ ID NO: 1 is A, a corn variety with white spot disease resistance is obtained.

9. A method for screening corn resistant to white spot disease, characterized in that: Take a corn sample to be tested and detect the expression level or genotype of the gene sequence shown in SEQ ID NO:

2. When the sequence shown in SEQ ID NO: 2 or its translated protein is overexpressed and / or the base at the 149156930th position from the 5′ end is T, it is judged to be a corn variety with white spot disease resistance.

10. A method for screening corn resistant to white spot disease, characterized in that: Take a corn sample to be tested and detect the SNP site, wherein the SNP site includes at least one of the sites 149153434, 149156506, 149157812, 149157853, 149157932, 149157959 or 149156930 located on chromosome 8 of corn, and the reference genome version where the SNP site is located is Zm-B73-REFERENCE-NAM-5.

0. When the bases of the SNP site are A, C, C, A, C, C and T respectively, it is judged to be a corn variety with white spot disease resistance.

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