Breeding method and propagation method for indica-japonica intermediate type sterile line Chunjiang 35A with early flowering time and high stigma exsertion rate

Abstract

The invention discloses a breeding method and a propagation method for an indica-japonica intermediate type sterile line Chunjiang 35A with early flowering time and a high stigma exsertion rate, and belongs to the field of utilization heterosis in hybrid rice. The breeding method disclosed by the invention comprises the following steps of selecting an indica-doped type late japonica rice maintainer line Chunjiang 19B with the characteristics of high stigma exsertion rate, early flowering time, resistance to the stripe virus disease and the like and a partial indica type maintainer line Chunjiang 23B with the characteristics of high stigma exsertion rate, very early flowering time and the like to carry out hybridization; then carrying out backcross by using a late japonica rice sterile line Chunjiang 16A with the characteristics of high stigma exsertion rate, very early flowering time and the like as a male parent; planting a backcross descendant, until B6F1 generation is low and the backcross descendant is stable, naming the backcross descendant as Chunjiang 35A. The indica-japonica intermediate type sterile line Chunjiang 35A bred by the method is early in flowering time, high in stigma exsertion rate, high in allogamous seed setting rate, high stress resistance (to be specific) and excellent in quality.

Description

technical field [0001] The invention relates to a breeding method of Dian I-type indica-japonica intermediate male sterile line, in particular to a breeding and propagation method of an indica-japonica intermediate male sterile line Chunjiang 35A with early flowering time and high stigma exposed rate. Background technique [0002] In recent years, in japonica rice areas and indica-japonica mixed planting areas in Jiangsu, Anhui, Zhejiang, Shanghai and other provinces and cities, the occurrence of stripe leaf blight of japonica rice varieties has increased year by year. Therefore, the breeding of new hybrid japonica rice combinations must pay attention to stripe leaf blight. In order to solve the resistance problem of stripe blight, the transfer of japonica rice sterile lines resistant to stripe blight has become one of the keys to the resistance breeding of hybrid japonica rice stripe blight. [0003] In addition to the excellent comprehensive traits of the new hybrid japoni...

AI Technical Summary

Problems solved by technology

Most of the three-line japonica sterile lines currently used in my country's production generally have no or low stigma exposure, late flowering time, low outcross seed setting rate and low seed production, which restricts hybrid japonica rice to a certain extent. The popularization and application of the new combination urgently requires the breeding of japonica male sterile lines with high outcrossing seed setting rate in order to increase the yield of seed production

[0004] In addition, the current japonica CMS lines in Zhejiang Province are mainly of late japonica type, such as Ning 67A, Yongjing 2A, Chunjiang 12A, Xiushui 110A and other CMS lines, all of which are late japonica CMS lines. Due to the limitation of the strong photosensitivity of the sterile line, the photosensitivity of the hybrid japonica rice or indica-japonica subspecies hybrid rice combination is also strong, and some combinations even have a long growth period and cannot be used in Zhejiang Province.

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