低温敏显性核不育水稻“8987”的育性转换与遗传研究

１９８９年在３３０４／明恢６３的Ｆ５代发现一个水稻雄性不育材料８９８７。它具有育性转换特性，温度是引起育性转换的主导因素，较低温时完全雄性不育，较高温时正常可育，结实率可达８０％。８９８７与其它品种正、反交Ｆ１代具有与它相同的育性转换，但组合间表现程度不完全一致。Ｆ２代在较低温度下发生育性分离时，有些组合Ｆ２不育株数：可育株数符合３：１，但有些组合可育株较多，分离比偏离３：１。这表明８９８７具有低温敏不育特性，它的不育性主要受细胞核内一对显性基因控制，遗传背景（微效修饰基因）对育性也有一些影响，是一种雄性不育新类型。

STUDY ON FERTILITY TRANSITION AND INHERITANCE OF THE LOWER TEMPERATURE THERMO-SENSITIVE DOMINANT MALE-STERILE RICE“8987”

A male-sterile rice plant“8987”(Oryza Sativa L. subsp indica)was found in F5 of the cross(3304/Minghui 63)in 1989. It has the fertility transition character. Temperature is the main factor to induce its fertility transition. It shows complete sterility under lower temperature conditions and normal fertility (with the seed-setting rate of above 80%)under higher temperature conditions. The F1 hybrids of 8987 when crossed or reciprocally crossed have the same fertility transition as 8987 does, but there are some differences between the F1 and 8987 and among F1 combinations. The F2 hybirds of some combinations are segregated in a ratio of 3 sterile to 1 fertile, but those of other combinations are segregated into less sterile plants and more fertile plants under lower temperature conditions. These results suggest that 8987 has lower temperature thermo-sensitive malesterility , its male-sterility is controlled mainly by a dominant male-sterile gene and somewhat influenced by genetic background yiz.minor genes. Therefore , it is a new type of male-sterile material.