温敏核不育水稻柱头外露率的群体改良研究——Ⅰ.不同群体改良方法对柱头外露率的改良效果

用温敏核不育水稻N8S作工具,选用长江流域早籼品种怀早4号、香2B和早优1号做材料,在兼顾综合性状的基础上,对温敏核不育水稻柱头外露率进行群体改良研究.结果表明,不同群体改良方法对水稻柱头外露率的改良效果不同.二次随机多交的改良效果最好;一次随机多交后混合选择的效果次之;单纯混合选择的效果最差.柱头外露率、包颈率和闭颖率3个异交习性都较理想的单株的频率以2次随机多交群体最高;1次随机多交后的混合选择群体次之;单纯混合选择群体最低.

A Study on Population Improvement on the Percentage of Exserted Stigma in Thermo-sensitive Genie Male Sterile RiceI . The Effect of Different Methods on the Improvement in Percentage of Exserted Stigma

Huaizhao 4, Xiang 2B and Zhaoyou 1 of early indica type in the Changjiang region were selected for population improvement on the percentage of exserted stigma in thermo-sensitive male sterile (TGMS) rice by using the recessive TGMS gene in N8S which was derived from Annong S - 1. It was concluded that different methods had different effect on improving the percentage of exserted stigma of TGMS line. Twice random polycross was the best, once random polycross plus mass selection was the next and mass selection was the worst for improving the percentage of exserted stigma. The frequency of plants with desired percentage of exserted stigma, percentage of spikelets enclosed in the sheath and percentage of cleistogamous spikelets was found highest in twice random polycross population, next in once random polycross plus mass selection population and lowest in mass selection population.