Breeding method for japonica two-line thermo-photo-sensitive genic male sterile line

Abstract

The invention discloses a breeding method for a japonica two-line thermo-photo-sensitive genic male sterile line. The breeding method comprises the following steps: selecting Shuxin 8S and japonica restorer line Xinjing 326, and carrying out sexual hybridization to obtain a Shuxin 8S / Xinjing 326 F1 generation; carrying out allopatric hybridization on the Shuxin 8S / Xinjing 326 F1 generation and Xinjing 221 to obtain a Shuxing 8S / Xinjing 326 / / Xinjing 221 F1 generation; and then carrying out backcross on the Shuxin 8S / Xinjing 326 / / Xinjing 221F1 generation and Xinjing 326, and carrying out shuttlegeneration-adding nursery breeding between north and south on the obtained F1 generation according to a genetic selection method to obtain the japonica two-line thermo-photo-sensitive genic male sterile line. According to the breeding method for the japonica two-line thermo-photo-sensitive genic male sterile line, an indica male sterile line and a japonica middle-long-neck restorer line are subjected to initial hybridization, then a short-neck japonica restorer line is subjected to alternate hybridization to obtain a wide compatibility application type japonica-indica two-line ear exposed neck genic male sterile line, the length of an ear exposed neck is 5-6 cm, and the degree of the ear exposed neck is 100%. The breeding method lays a firm foundation for transformation of Chinese hybridrice into environmentally large-area production seed planting promotion.

Description

technical field [0001] The invention relates to the technical field of agricultural planting, in particular to a method for breeding two lines of japonica thermo-photosensitive male sterile lines. Background technique [0002] Rice belongs to the Poaceae Oryza genus and is an extremely ancient crop. The history of artificial planting in my country has been at least 7,000 years. After long-term evolution and artificial domestication and creation under different ecological conditions, rice has been differentiated into two subspecies: indica rice and japonica rice. my country's hybrid rice breeding technology is leading the world. At present, the hybrid rice CMS used in the world is divided into two categories: three-line CMS and two-line CMS; three-line CMS is divided into indica three-line CMS and japonica CMS. Three-line CMS, two-line CMS are divided into indica two-line CMS and japonica two-line CMS; the existing two types of CMS both have the technical problem of ear wrappi...

AI Technical Summary

Problems solved by technology

China, which is the world leader in hybrid rice breeding technology, has been on the road for more than 40 years. The reason why the problem of panicle neck wrapping in the breeding industry cannot be solved is that the breeding creation method and direction stand in line, the materials and creation follow the trend, and the innovation and breakthrough of technology are not mutually beneficial. The beginning of ear wrapping in male sterile line has not been resolved

[0003] The ear-neck CMS line was developed by Chinese breeders as early as the mid-1980s. However, due to many disadvantages in its own creation technology (excessive neck length of more than 13cm), only 30% of the ears are set in practice, and the ear necks are only 30%. The breakage causes the complete production to be unusable; the existing sterile line is only slightly changed in the wrapping degree, and only solves the percentage problem; although the current sterile line breeding adopts the combination of genetic and molecular breeding in the application of innovative technology, it is still in the In terms of the key technology, it is still impossible to break the practical type of male sterile line that can be perfectly integrated in one body.

[0004] At present, the panicle wrapping degree of the existing sterile lines is more than 40%-60%. It is necessary to spray a large amount of hormone medicament 920 during seed production. If it is too low, it will cause great economic losses to seed farmers and enterprises, and at the same time increase the cost of seeds and increase the cost of planting for farmers who grow grain. The continuous increase in income also causes air pollution; if the existing male sterile lines use a small amount of hormones, the ears in the trousers cannot be completely extracted, and the florets cannot be fertilized, which leads to low yields in field seed production and low seed production. The risk of purity increases, which is even more unfavorable for farmers to increase income and enterprises to increase efficiency; the existing sterile line such as 920 will kill glumes when used in a small amount, making the color of seed grains brown or cracking glumes, resulting in losses such as unqualified seeds