176 results about "Test cross" patented technology

The invention discloses a method for breeding colored rice two-line hybrid rice. The method comprises the steps of carrying out hybridizing by taking colored rice +C as a male parent and a two-line sterile line S as a female parent, and carrying out backcrossing with the female parent to obtain BCnF2 generation seeds; selecting male sterile plants, carrying out paired test cross on the male sterile plants and a two-line restoring line R, and selecting and maintaining homozygous sterile line plants with colored seed coats and corresponding hybrid seeds; detecting seed heterosis, and selecting and maintaining hybrid plants and sterile line plants with heterosis to obtain colored rice sterile line seeds; identifying the fertility, yield, quality and resistance of the sterile line to obtain excellent colored rice sterile line plants; and breeding seeds to obtain a colored rice two-line hybrid system. According to the method, the colored rice and the two-line sterile line of the approved hybrid rice are hybridized and backcrossed, and the two-line sterile line plants with the colored seed coats and heterosis are screened through the restoring line, so that the obtained colored rice hybrid rice and the sterile line thereof not only have the colored seed coats, but also have the advantages of high yield, high quality and disease resistance.

The present invention uses rice intermedium type sterile line as female parent, uses intermedius type restoring line as male parent for cross breeding rice hybrid species. Said invention also includes that uses hsien rice sterile line and intermedius sterile line as female parent and uses rice hsien-keng crossed duplex haploid (DH) population and hsien-keng crossed recombinant inbred line (RIL) population as male parent to make test cross to obtain four hybrid populations of hybrid F1 generation. By detecting character of F1 and using hisen-keng molecule specific probe to detect keng-type index of F1 correspondent to male parent DH and RIL the F1 character-male-type keng-type index correlation can be obtained.

The present invention discloses a method for breeding Brassica napus varieties and materials with a double haploid induction line of rapeseed, including: 1) determining target traits of breeding restorer lines, maintainer lines and conventional varieties of Brassica napus; 2) crossing or convergently crossing two or more Brassica napus with the target traits; 3) pollinating the cross or back-cross progenies with the double haploid induction line of rapeseed; 4) identifying the stability of the induced progenies; 5) performing test-cross identification or yield and resistance identification on the stable progenies; and 6) forming stable restorer lines and maintainer lines for cross breeding combination or for forming conventional varieties. The present invention can quickly and efficiently obtain rapeseed materials or conventional varieties with application value in breeding on a large scale, and lays a solid foundation for genetic breeding of Brassica napus, innovation of breeding resources, breeding of conventional rapeseed varieties, and breeding of new varieties of hybrid rapeseed. The method of the present invention can greatly improve the breeding speed and efficiency of hybrid or conventional varieties of Brassica napus, and reduce the human and material resources.

The present invention is cross breeding process of color trilinear cotton hybrid. Pigment gene is led into restoring line to be improved to breed color cotton restoring line with strong restoring capacity to fertility of cytoplasmic male sterile line. Pest and disease resisting gene and pigment gene are transferred into sterile line to breed color cotton cytoplasmic male sterile line with resistance to cotton blight, bollworm and pink bollworm separately. Through test cross and screening with color cotton type sterile line and white cotton restoring line or white cotton sterile line and color cotton restoring line, combined advantageous hybrrid F1 with high yield, high quality and high resistance is bred. The present invention can express the heterosis sufficiently.

The invention relates to a method for breeding a novel strain of anurous laying hens. The method includes steps of (1), selecting mutant anurous cocks and hens from indigenous chicken or laying hen resources and enabling the cocks and hens to perform self-reproduction to expand propagation; (2), selecting anurous cocks and hens from descendents of the expanded propagation, introducing blood relationship of high-yield laying hens into the anurous cocks and hens, selecting anurous cocks and hens in hybrid descendents, enabling the anurous cocks and hens to perform cross-breeding, and selectively reserving anurous cocks and hens in cross-bred descendents; (3), performing test-cross on the reserved anurous cocks and hens, evaluating the anurous cocks and hens and screening individual cocks and hens which are anurous genetic homozygous and enabling the individual cocks and hens to perform self-reproduction to expand propagation; (4), selecting the anurous genetic homozygous cocks and hens and improving the bodily form and appearance uniformity and the laying performance of the anurous genetic homozygous cocks and hens; (5), repeating executing the steps (3) and (4) until the novel strain of laying hens with the anurous character capable of being stably inherited. Appearance features of the anurous cocks and hens in cross-bred descendents meet requirements of breeding objectives. The method has the advantages that the bred novel strain of anurous laying hens is fast in growing speed and high in dressing percentage and egg numbers, and requirements of modern laying hen and broiler production can be met.