应用群体改良技术选育水稻温敏核不育系的研究

Develop Thermo-sensitive Genic Male Sterile (TGMS) Rice Line by Means of Population Improvement

应用随机多交加混合选择的方法 ,不仅可以改良单个性状柱头外露率 ,而且可以改良配合力、品质、抗性等综合性状。从用N8S、怀早 4号、香 2B和早优 1号构建的两次随机多交加混合选择的群体中选育出一个柱头外露率高、配合力、品质和抗性都较对照V2 0A有明显改善的实用温敏核不育系准S。准S柱头外露率达 78 6 % ,比对照V2 0A高72 4 %。用准S与R4 0 2、明恢 77和明恢 6 3配组育成的两系杂交稻新组合比V2 0A的对应组合增产 3 8%～ 5 8% ,垩白度小 82 1%～ 84 4 %。

TGMS line is the key for breeding two line system hybrid rice Population improvement, or random polycross plus mass selection was adopted in this study, using N8S, Huaizao 4, Xiang 2B and Zaoyou1 as parents It was concluded that population improvement could help comprehensively improve the important characters like combining ability, grain quality, resistance, stigma exsertion etc Especially an elite TGMS line—Zhun S had been developed and performed very well The stigma exsertion rate of Zhun S was 78 6%, 72 4% higher than that of V20A Hybrids crossing Zhun S with R402, Ming hui 77 and Ming hui 63 yielded 3 8%-5 8% higher and decreased chalkiness by 82 1%-84 4% than those crossing V20A with the corresponding R lines