Breeding method for high-temperature-resistant and disease-resistant rice two-line sterile line

Abstract

The invention discloses a breeding method for a high-temperature-resistant and disease-resistant rice two-line sterile line. The breeding method includes the steps that the rice two-line sterile line S is used as a female parent, a high-temperature-resistant glutinous rice farm variety C is used as a male parent and hybridized with the female parent, and the generation F1 is expressed through S*C; the generation S*C is used as a female parent during planting in the second season, a three-line maintainer line B resistant to rice blast and false smut is used as a male parent and is subjected to composite hybridization with the female parent, and composite hybridization seeds (S*C)*B are harvested after composite hybridization; the generations F2-F4 are subjected to composite hybridization; the generation F5 is subjected to composite hybridization, and a generation F5 two-line sterile line single plant is hybridized to prepare a hybridization testing combination; after hybridization testing seeds are harvested, rice bags are cut for generation adding; the single plant selecting and generation adding method of the generation F6 is the same as that of the generations F2-F4; the generation F7 is subjected to composite hybridization, and the selected two-line sterile line is basically set. The rice two-line sterile line capable of seeding well at high temperature and capable of resisting rice blast and false smut can be bred through the method, the defects that an existing two-line rice variety is low in high-temperature seeding rate and poor in disease resistance can be overcome, and a high and stable yield two-line hybrid rice variety can be cultivated easily.

Description

technical field [0001] The invention belongs to the field of agricultural breeding and can be directly applied to parental selection of hybrid rice by "two-line method". Background technique [0002] At present, the "two-line method" hybrid rice varieties are developing rapidly in the middle and lower reaches of the Yangtze River in my country, and the planting area in this area exceeds that of the "three-line method" hybrid rice varieties. However, in the high temperature and drought areas of the upper reaches of the Yangtze River, the proportion of "two-line" hybrid rice varieties is still smaller than that of "three-line" hybrid rice varieties. Not very strong, which restricts the further development of two-line hybrid rice varieties. The heat tolerance and disease resistance of hybrid rice varieties are related to their parents, which directly determine the heat tolerance and disease resistance of hybrid rice varieties. [0003] There are two defects in the existing tw...

AI Technical Summary

Problems solved by technology

[0003] There are two defects in the existing two-line sterile lines: the first is that the existing two-line sterile lines have poor high temperature resistance, which causes low seed-setting rate of hybrid rice varieties in high-temperature and summer-drought areas, which affects the yield of hybrid varieties; The two-line CMS lines have weak resistance to rice blast and rice false smut, which may cause rice yield reduction in mild cases, or failure in severe cases

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