Seed selection method of high stigma exsertion rate japonica two-line sterile line

Abstract

A seed selection method of a high stigma exsertion rate japonica two-line sterile line belongs to the fields of two-line hybrid japonica rice genetic breeding and seed production. The method comprises the following steps: 1 choosing a two-line sterile line with a high stigma exsertion rate as a donor parent; 2, hybridizing the donor parent with a japonica two-line sterile line; 3, selecting individual plants with the stigma exsertion rate reaching above 95% from the above obtained F2 generation; 4, selecting materials with high stigma exsertion rate and stable and consistent group properties from the above obtained F3 to F7 generations; 5, carrying out high stigma exsertion rate gene positioning on the obtained materials, and selecting low initial temperature materials by using a greenhouse; 6, hybridizing the materials obtained in step 5 with conventional japonica rice, backcrossing the F2, selecting thoroughly abortive individual plants from BC1F2, cutting spikes, and collecting seeds; 7, continuously inbreeding the obtained materials in Hainan to F4, experimentally planting the BC1F5 in different latitude regions, selecting temperature and light-insensitive sterile individual plants, cutting spikes, and collecting seeds; and 8, carrying out stigma exsertion gene detection on the obtained materials, and finally screening a two-line sterile line material with a high stigma exsertion rate. The method can significantly improve the breeding efficiency and the seed yield.

Description

1. Technical field [0001] The invention belongs to the field of genetic breeding and seed production of two-line hybrid japonica rice, in particular to a method for breeding a japonica two-line male sterile line with a high stigma exposure rate. 2. Background technology [0002] There are two subspecies of indica and japonica cultivated in Asia. Most of the typical indica rice has the character of exposed stigma, and the rate of exposed stigma of typical japonica rice is very low, generally about 0.2%. The two-line hybrid rice is an original high-tech technology in my country that focuses on the utilization of photothermo-sensitive sterility. It is another major scientific and technological innovation in rice genetics and breeding after the three-line hybrid rice. Compared with the three-line method, the two-line method has significant advantages: the male sterile line and the restorer line can be combined freely, and the probability of selecting a good combination is high; ...

AI Technical Summary

Problems solved by technology

In addition, due to the short opening time of rice spikelets, the sterile line cannot accept pollen for fertilization, and the final seed production yield is low, which has become a bottleneck in the development of hybrid japonica rice production.