84 results about "Recurrent selection" patented technology

The invention discloses a method for breeding wheat cultivar, comprising the following steps: a. taking a dominant sterility gene Ta1 material as a female parent, and carrying out single cross or multiple cross on a breeding parent material containing required genetic components for combined hybridization to obtain a recurrent selection group CO; b. carrying out mutual hybridization recurrent selection on the descendant of the recurrent selection group CO to obtain a recurrent descendant Cn; and c. breeding the recurrent descendant Cn, building different adverse-situation or non adverse-situation seed selection environments on the same site, and carrying out adverse-situation or non adverse-situation alternate selection and a yield ratio qualification test among generations to cultivate the excellent cultivar of wheat. The wheat cultivar cultivated with the method provided by the invention has the advantages of stress resistance, water saving property, yielding ability and wide adaptability.

The invention relates to a method for carrying out recurrent selection breeding on water-saving and drought-resisting rice by utilizing a dominant nuclear male sterile material. The method comprises the steps of hybridizing by using the dominant nuclear male sterile material as a female parent and the water-saving and drought-resisting rice as a male parent, and backcrossing by five times, thus obtaining a water-saving and drought-resisting rice dominant nuclear male sterile plant; then hybridizing by using the water-saving and drought-resisting rice dominant nuclear male sterile plant as the female parent and 15 to 30 kinds of good parents as the male parent, and equivalently mixing offsprings to form a first round of recurrent selection populations; planting the first round of recurrent selection populations in a dry land, carrying out artificial supplementary pollination during a heading stage, selecting seeds on good sterile plants during a maturing stage, and equivalently mixing the seeds to form a second round of recurrent selection populations; repeating the recurrent selection process; selecting good fertile individual plants from the recurrent selection populations at any time, entering a pedigree method, and breeding a new variety of the water-saving and drought-resisting rice. The method for carrying out the recurrent selection breeding on the water-saving and drought-resisting rice by utilizing the dominant nuclear male sterile material, disclosed by the invention, has the advantages that the dominant nuclear male sterile material is used as a carrier, materials of the water-saving and drought-resisting rice and materials of good rice are in wide hybridization, and the genetic basis of existing water-saving and drought-resisting rice is greatly enriched.

The invention discloses a method for recurrently and selectively breeding non-glutinous rice by using a recessive cytoblast sterile material, which mainly comprises the following steps: hybridizing a sterile strain with recessive cytoblast sterile gene ms-np serving as a female parent and 20 to 30 rice materials serving as male parents, and backcrossing one generation; then, selecting seeds on excellent sterile strains in the later generations, and equivalently mixing the seeds to form a first recurrent selective population; and repeating the recurrent selection process, selecting the excellent fertile strains to a pedigree method at any time, combining molecular marker-assisted selection, and breeding a new variety. The method has the advantages that: recessive cytoblast sterility is used for performing a large amount of hybridization so as to enrich the hereditary basis of the breeding material; new rice materials can be added at any time so as to continually improve the population; moreover, the method avoids manual castration and pollination so as to save a large amount of manpower; and by utilizing a DNA molecular marker for assisting in selection, the method shortens the breeding progress and time, and reduces the breeding cost.

The invention discloses a molecular marker which is used for corn tripsacum monosome addition line nucleic male sterility genes and belongs to the field of crop molecular markers. The molecular marker is composed of nucleotide sequences shown by SEQ ID No:1. The invention further discloses an SCAR primer pair used for amplifying the molecular marker and composed of SEQ ID No:2 and SEQ ID No:3. In addition, the invention further discloses a method of using the molecular marker for backcross and recurrent selection breeding. The molecular marker is not limited by time and environment conditions, can identify and screen the corn tripsacum monosome addition line nucleic male sterility genes at the seedling stage, selects and weeds out the nucleic male sterility genes easily, saves manpower and material resources in large quantities, improves the breeding efficiency, shortens the breeding process and time, and substantially reduces breeding cost. In addition, the molecular marker can serve as a tool for large-scale recurrent selection for corns and continuously extend the corn heredity basis and is beneficial for selecting out a breakthrough corn variety.

The invention discloses a high-oil routine rape variety recurrent selection method. The method comprises the following steps: 1, classifying materials, and establishing a base recurrent selection colony; 2, selecting a recurrent selection colony; and 3, establishing a high-oil recurrent selection colony, and breeding a high-oil routine variety. A new variety of double-low routine oil rape, with the advantages of high oil content, good yielding ability, strong stress resistance and wide adaptability is cultivated through fusing genes controlling the oil content, the yield and the stress resistance, and a new feasible high-oil routine rape breeding approach is provided.

The invention provides a brassica napus cytoplasmic male sterile restore line population improvement method. The method comprises the following steps: a restore line is taken as a female parent and is hybridized with a plurality of inbred lines, a first filial generation selects a fertile plant as a female parent for backcross and inbred for a generation, restore gene locus homozygous single plants are selected through identification, equivalent seeds are taken from each single plant and mixed to form an S0 population, the S0 population is sown, a chemical inducer is sprayed to the female parent, open pollination is carried out in the population to harvest chemically-induced sterile plant seeds to form a recurrent selection population S1, then recurrent selection is carried out for at least 6 times, and a DH single plant obtained by carrying out field planting and microspore culture on a screened target single plant is a brassica napus cytoplasmic male sterile restore line. According to the method, a chemical induction method is initiatively adopted to acquire a sterile plant, so that the time and the labor are saved, and finally, the genetic basis of the restore line is wide; and more importantly, in the process of applying a chemically-induced sterile plant to carry out recurrent selection, the ratio of restore genes in the recurrent population is stable to be 100 percent.

The invention relates to a breeding method for fresh-eating red waxy hybrid maize belonging to the hybrid maize breeding field, comprising the procedures as follows: black pearl waxy corn with perfect plasmid and modena grain chosen as male parent and Darfur waxy corn with perfect plasmid and silvery white grain chosen as female parent are hybridized to establish an underlying group; recurrent selection is carried through in the underlying group in the aspects of red grain, waxy property, sweet taste, single plant production capacity, the ability of anti tan disease and lodging resistance, and repeated anisotropic hybridization and self-pollination are carried through to establish a hybridization group; the self-fertilization of parent strain and retrogression choiceness of the hybridization group are completed, vermeil hard grain is produced after 4-6 generations. The breeding method of the invention can breed the fresh-eating and eatable red waxy corn with high officinal value, good mouthfeel, high contents of natural haematochrome and rich nutrition which can be used in industry and as feed and has the advantages of strong ability to resist disease, drought resistance, flood resistance, high yield and fertility.