98 results about "Backcrossing" patented technology

A method for selectively culturing the new variety of wheat includes such steps as respective crossing between the wheat 'Aibai' as female parent and 15-20 excellent varieties as male parent to obtain F1 generation, respective backcrossing between the dwarf sterile plants as female parent and the said male parent to obtain the backcrossed seeds F1, mixing them together, free pollination between fertile plants and sterile plants to obtain the seeds, mixing, free pollination between dwarf sterile plants and non-dwarf fertile plants to obtain seeds A, controlled pollination between the high-quality dwarf sterile plants as female parent and the specific plants as male one to obtain seeds B, proportionally mixing seed A with B, repeating said steps to obtain improved group, and culturing the excellent fertile plants by genealogical method.

The invention relates to a breeding method of hybrid cabbage, in particular to a simplified breeding method for preparing hybrid cabbage by using cytoplasmic male sterile lines, which belongs to the technical field of plant culture. The invention directly adopts the cabbage varieties of Zhonggan No.22 and Hugan No.2 prepared by cytoplasmic male sterile lines sold in the market as maternal plants, and adopts cabbage inbred lines (with the same ball shape as the maternal plants, the same type of leaf ball mature performance as the maternal plants and stable botanical characters) as pollen suppliers for preparing good coenospecies. The invention has the advantages that when the advantages of using the cytoplasmic male sterile lines for preparing the cabbage coenospecies are maintained, good cabbage inbred lines do not need to be used as recurrent parents for fifth to seventh generation backcrossing and transformation with male sterilant materials, the labor is saved, the cost is saved, the breeding time is greatly shortened, and in addition, the hybrid vigour parts of the original varieties can be maintained into the new hybrid varieties.

The invention discloses a continuous recessive character backcrossing technology which is characterized by taking a material which contains no target recessive genes and is ready to be improved as a recurrent parent, and taking a material which contains the target recessive genes as a donor parent; taking the recurrent parent as the parent to be hybridized with the donor parent and harvesting hybrid seeds of the first generation F1 and recurrent parent seeds; and planting the hybrid seeds of the first generation F1 and the recurrent parent seeds till the planting of a group containing backcross hybrid seeds of the second of n generations BCn F2 and till the typing into a target recessive gene isogenic line of the recurrent parent. The invention also discloses a method for creating a purpleleaf marker isogenic line by applying the continuous recessive character backcrossing technology and also a method for transferring new purple leaf marker nucleus sterile line by taking the purple leaf marker isogenic line as an intermediate material. In the methods, a selfing process is combined with a next backcrossing process for the treatment in one season, therefore, the time efficiency is improved by about 50 percent, a small number of dominant-gene-controlled unsuitable characters of existing fine-quality parents can be fast improved, and useful recessive characters can be fast imported to the present high-level heredity background.

The invention discloses a QTL-seq based method for mining a cold-tolerant gene of Dongxiang wild rice. According to the method, cultivated rice 'Xieqing Zao B' is taken as a receptor parent, namely, a female parent; the Dongxiang wild rice is taken as a male parent; a recombinant inbred line BC1F10 obtained by distant hybridization and continuous backcrossing is subjected to cold tolerance identification; obtained 20 cold-tolerant strains form a cold-tolerant gene pool; and 20 cold-sensitive strains form a cold-sensitive gene pool. The two gene pools are subjected to high-throughput sequencing and QTL-seq analysis to obtain differential SNP makers and cold-tolerant character related QTL loci of the two gene pools; candidate cold-tolerant genes are subjected to fluorescent quantitative PCR detection; and finally the Dongxiang wild rice is detected to contain five cold-tolerant related genes by identification. According to the method, the cold-tolerant genes of the Dongxiang wild rice can be quickly and accurately detected and mined, a powerful evidence can be provided for comprehensively illuminating a genetic mechanism of cold tolerance character of the Dongxiang wild rice, a foundation is laid for cloning and functional analysis of the cold-tolerant genes of the Dongxiang wild rice, and the breeding practice of the cold-tolerant genes of the Dongxiang wild rice is facilitated.

The invention relates to a method for hybrid rice variety breeding and safe and high-efficiency seed production by use of sensitivity character of a weed killer and color character of a specific rice husk. The method is characterized in that marker characters (weed killer sensitive lethal and specific rice husk color) are utilized and genetic improvement methods such as hybridization, backcrossing, self-crossing and the like are comprehensively utilized, double differences of the rice husk color and the weed killer sensitivity are created between parents of hybrid rice, male parent and female parent of the hybrid rice, containing different marker characters and suitable for mechanized seed production, are cultivated, the weed killer is sprayed for killing the male parent and the sorting technology of a seed color sorter is adopted according to the different marker characters after mechanical mixed sowing (transplanting), so that under the condition that the purity of the hybrid seed is guaranteed, the mechanized hybrid rice seed production is realized, the seed production efficiency is improved, and safe and high-efficiency production of the hybrid rice seed is achieved.

The invention relates to the field of breeding and specifically relates to a multi-ecological-area recurrent mixed selection - mixed planting cotton breeding method, which comprises the following steps of: 1) preparing cotton hybridized combinations; 2) reproducing generation F1 hybrid seeds in the south for increasing the generation; 3) respectively sowing generation F2 seeds in cotton regions of the Yellow River Valley, the Yangtze River Valley and the northwest inland; 4) selecting generation F3 seeds of excellent individual plants and reproducing in the south for increasing the generation; 5) respectively sowing generation F4 seeds in the cotton regions of the Yellow River Valley, the Yangtze River Valley and the northwest inland; and 6) selecting generation F6 seeds of excellent individual plants, sowing the seeds in hybrid seed production fields and selecting excellent individual plants according to breeding purposes. The method provided by the invention complements a modified backcrossing and recurrent selection method and improves the yield, the quality and the insect resistance. The method has the advantages of high breeding efficiency, diversified varieties, high adaptability, high purity and good consistency, and lays a foundation for breeding better varieties in future.

The invention provides a molecule marker of brown planthopper resistant gene. According to the present invention, through the hybridization and backcrossing of a resistant parent RBPH54 and a susceptible variety TN1, progenies are obtained. Through respective resistance identifications and molecule genetic linkage analysis of the progeny strains, a brown planthopper resistant major recessive genebph20(t) is obtained. Two nearest molecule markers linked beside bph20(t) are BYL7 and BYL8, which are self-developed SSR markers. The distances from the markers to bph20(t) are 1.3cM and 1.2 cM. With molecule markers linked to the brown planthopper resistant gene, the detection can be carried out to detect whether the pest resistant variety RBPH54 or the derivative varieties (systems) of RBPH54 contain the pest resistant genetic locus. Therefore, the selection of brown planthopper resistant paddy varieties or paddy qualities can be substantially improved in efficiency.

The invention discloses a novel selective breeding method for a male sterile line of Sichuan preserved pickle cytoplasm brasica napus. According to the method, a sterile source of the Sichuan preserved pickle is transferred into the brasica napus through distant hybridization and continuous backcrossing between different inter-species in brassica, so as to obtain Sichuan preserved pickle cytoplasm brasica napus CMS '93-12A'. The Sichuan preserved pickle cytoplasm brasica napus CMS '93-12A' is improved by hybridization and continuous backcrossing, so as to obtain a novel, stable, and double low sterile line material 'Jia rapeseed 58A'; the identification of the restoring and maintaining relationship of the Sichuan preserved pickle cytoplasm CMS shows that the restoring and maintaining relationship of the 'Jia rapeseed 58A' is different from the restoring and maintaining relationships of Pol CMS and Shaan 2A CMS, and meanwhile, one part of restorer material is screened out, and is improved to obtain five parts of double haploid restorer materials; the PCR identification with a specific primer shows that sterile sources of the '93-12A', the 'Jia rapeseed 58A' and mustard CMS are the same; an identification result of hybridization mating group yield of the 'Jia rapeseed 58A' and different restorer materials shows that a part of the combinations have a good yield-increasing potential, and the 'Jia rapeseed 58A' has a good combining ability. The method provided by the invention can be applied to the selective breeding of rapeseed varieties and the planting of the rapeseed in production.

The invention discloses a method for improving a brassica napus type temporary maintainer line of nuclear recessive epistatic interaction sterility in rapes. The method comprises the following steps: selecting a homozygous two-type line strain B to cap and self-cross, selecting an individual plant from a sterile segregation population to hybridize with a to-be-improved temporary maintainer line; then, taking the sterile segregation plant as a recurrent parent to continuously backcross and self-cross, and test cross to breed a new temporary maintainer line after the backcrossing; hybridizing the temporary maintainer line with the homozygous two type line to obtain a complete sterile line, wherein sterile plants account for 100% of the complete sterile line. The bred temporary maintainer line is stable in heredity, very close to the homozygous two type line genetic background, the obtained complete sterile line is easily compounded with a restoring line to prepare strong superiority hybridized combination, and a novel excellent hybrid rape variety is obtained by screening. The invention provides a novel technical method for widely applying a nuclear recessive epistatic interaction sterility pollination control system with a development prospect to the production practice.

The invention belongs to the field of genetics and discloses a breeding method for new varieties of drought-resistant wheat. Gaocheng 9411 serves as the female parent, ATHLET serves as the male parent, continuous selection is conducted through plant-to-row for generations, and the drought-resistant wheat strains JM205 and JM208 high in waxiness are created; Jimai 22 serves for backcrossing and conducts backcrossing with the drought-resistant wheat strains JM205 and JM208 high in waxiness respectively, six generations of BC6F-5 and BC6F1-8 strains are backcrossed for expanding propagation, waxiness of flag leaves is tested, testing and calculation of physiological indexes about drought resistance are conducted, and the wheat strains J-JM205 and J-JM208 which are high in waxiness, resistant to drought and high in yield are created. According to the breeding method for the new varieties of the drought-resistant wheat, conventional visual inspection conducted at the early stage of backcrossing and index testing conducted at the later stage are adopted, breeding cost is saved at the early stage, and accurate selection is conducted at the later stage.

Described herein are methods and materials useful for improving root growth and nutrient uptake in cereal grasses. In particular, present disclosure provides methods for increasing root growth and nutrient uptake in a cereal grass involving marker assisted selection and backcrossing. The present disclosure also provides recombinant DNA for the generation of transgenic plants, transgenic plant cells, and methods of producing the same. The present disclosure also provides materials and methods useful for improving the tolerance of a cereal grass to phosphorus-deficiency The present disclosure further provides methods for generating transgenic seed that can be used to produce a transgenic plant having increased root growth, nutrient uptake, and phosphorus-deficiency tolerance.

The invention belongs to the field of genetics, a molecular marker for rapid detection of high yield gene of Thinopyrum elongatum and its application are provided, by conventional hybridization, backcrossing and greenhouse and artificial climate chamber generation techniques, a near-isogenic line of high yield gene 7el2L of Thinopyrum elongatum was created. Combined with fluorescence in situ hybridization (FISH) and analysis of agronomic and yield-related traits, molecular markers closely linked to 7el2L were obtained, which could be used in wheat breeding for high yield and early molecular-assisted selection for yield-related traits, in order to improve breeding efficiency.

The invention belongs to the technical field of flower breeding, and particularly relates to a transformation method of a zinnia male sterile dual-use system. The invention takes a sterile plant of a zinnia male sterile dual-use system AH209AB as a parent plant, takes a zinnia inbred line as a father plant, and after cross breeding, inbreeding, continuous backcrossing, group pair hybridizing and restoring and maintaining test, an orangered single recessive zinnia male sterile dual-use system J16AB is finally transformed and obtained. The invention can transform a male sterility gene into an inbreeding line with excellent properties, obtains the zinnia male sterile dual-use system with consistent gardening properties, thorough abortion and stable fertility inheritance, enriches the breeding materials, and lays the foundation for the zinnia crossbreeding. During the transformation process, through the phenotype characteristics of floral organs, the invention can accurately analyze and judge the fertile plants and the sterile plants of the zinnia, and provides phenotype marks for zinnia fertility identification.

A method for increasing the high yield potential of hybridized rice includes hybridizing and continuous backcrossing to introduce the high-yield genes yld 1.1 and/or yld 2.1 of Malaysian wild rice O. rufipogon to the parent of hybridized rice, descriminating the plants carrying said high-yield gene by molecular marker aided selection, analysis, screening the dominant plants, breeding the strong and dominant recovery line, and pairing the combination of cross rice.

The invention provides a method for cultivating very early-maturing rice and belongs to the field of crop genetics and breeding. The invention relates to the utilization of a main spike early-maturingrice material, for a characteristic that a main spike maturation period and a tiller spike maturation period of the main spike early-maturing rice material have a large difference, and a strategy forreducing the tiller number of the rice and shortening the maturation period of the whole plant is proposed, which means that the purpose of controlling the rice maturation period is achieved by controlling the tiller number of rice. A less tiller early-maturing rice material is created through a cross breeding technique or genome editing technique, then the less tiller early-maturing rice material and excellent rice varieties are hybridized, followed by continuous backcrossing, a less tiller early-maturing rice individual is selected, a less tiller early-maturing excellent rice variety with agrowth period within 90 days is obtained, and the early-maturing rice variety is particularly suitable for direct seeding cultivation in rice production.

The invention discloses a mutant gene OsCOPT7 of rice copper low accumulation mutant lc1 and application of the gene. According to the mutant gene OsCOPT7 of rice copper low accumulation mutant lc1, abase mutation occurs in the coding region of a wild OsCOPT7 gene, namely, the 344th base downstream of ATG is mutated from G to A, and the 115th codon in the coding region is changed from GGG to GAG,so that the amino acid at position 115 in the protein sequence is mutated from glycine (Gly/G) to glutamic acid (Glu/E). the coding nucleotide sequence of the mutant gene OsCOPT7 is shown in SEQ ID No. 1, and the amino acid sequence is shown in SEQ ID No. 2. The copper content in rice grains of mutant lc1 is significantly lower than the copper content in rice grains of the wild type. The application of the mutant comprises one or more of transgene, hybridization, backcrossing or asexual reproduction; and the application of the mutant gene OsCOPT7 comprises enabling rice to contain the mutantgene OsCOPT7, or enabling rice to contain the amino acids encoded by the mutant gene OsCOPT7.