两系杂交水稻糙米率的配合力研究

Combining ability studies on brown rice percentage of rice hybrids by two-line method

选用8个籼型光温敏不育系作母本,30个恢复系品种作父本,共配制两系杂交水稻组合74个,进行两系杂交水稻糙米率配合力遗传研究.结果表明:1)两系法杂交水稻杂种F1谷粒的糙米率与父本(恢复系)和双亲平均的谷粒糙米率呈极显著正相关,相关系数为0.3123和0.3068;与母本(不育系)谷粒糙米率相关不显著,相关系数为0.1031.2)6×6不完全双列杂交法配合力分析结果表明,两系杂交水稻糙米率性状的表现在组合间差异极显著;父、母本的一般配合力效应和组合的特殊配合力效应差异显著;父、母本的一般配合力作用大于组合的特殊配合力作用,一般配合力方差占总个基因型方差的65.02%,特殊配合力方差占34.98%;一般配合力作用,父本的作用(基因型方差为63.70)大于母本的作用(基因型方差为55.34).

74 combinations were obtained by crossing 8 photo-thermo-sterilities with 30 restoring line varieties, and their combining ability of brown rice percentage was studied. The main results were as follows： 1） Brown rice percentage of hybrids （Fi） was significantly positively correlated with that of the male parentages and the mean level of two parents, and the correlation coefficient were 0.312 3 and 0.306 8; slightly positively correlated with brown rice percentage of the female parentages, and the correlation coefficient is 0.103 1. 2） The difference of brown rice percentage was significant among combinations; The difference of brown rice percentage between general combining ability （GCA） and special combining ability （SCA） of combinations was significant; The brown rice percentage of hybrids was controlled by GCA and SCA, and GCA of parents, especially the restoring line parents, played a more important role. percentage in rice hybrids （FD by two-line system were At last, the breeding methods of improving brown rice discussed.