水稻籽粒不同发育时期灌浆速率的遗传及其与环境互作的分析

Analyses of Genotype and Environment Interaction and Heredity of Filling Rate in the Different Developmental Stages of Rice Grain

以 6个水稻品种作完全双列杂交 ,应用包括基因型×环境互作的三倍体胚乳遗传模型及条件遗传方差分析方法 ,对水稻灌浆速率进行动态遗传分析。结果表明 ,不同类型水稻品种及其组合在不同时期测定的灌浆速率存在明显差异。水稻灌浆速率主要受三倍体胚乳核基因及二倍体母体植株基因的遗传控制 ,细胞质效应较小 ,并且以胚乳核基因的加性效应为主。基因型×环境的互作效应主要表现为母体加性×环境互作。灌浆速率后代的分离主要决定于水稻开花后 18d之前。各时期母体植株基因的遗传效应对水稻灌浆速率均有一定作用 ,并且水稻开花后 18～ 2 4d母体植株基因对灌浆速率的效应比胚乳核基因还大。各时期均以种子直接遗传率为主 ,母体遗传率很低 。

Using a genetic model of triploid endosperm including interaction of genotype×environment and statistical approaches of conditional genetic variances, the dynamic changes and genetic effects on grain filling rate of rice were studied with completed diallel cross of 6 rice varieties. The results indicated that the grain filling rate of rice varied largely with measuring time in the developmental stage of rice grain for various types of rice varieties and crosses. The grain filling rate was mainly controlled by triploid endosperm and diploid maternal plant genetic effect. The cytoplasmic effect was small, the endosperm additive effect was the major effect at the grain filling stage. The maternal additive × environment interaction was the major component of interaction in all components of interaction. The results of conditional genetic variance components showed that the grain filling rate was mainly determined before 18 days after flowering. The grain filling rate was also affected by genetic effects of maternal plant in the filling stage of rice. The genetic effects of maternal plant were larger than that of endosperm for a grain filling rate in the range of 18～24 days after flowering. Analysis of heritability demonstrated that the seed direct heritability was much higher than the heritability of maternal plant. The action of maternal additive effects were weakened by the covariance between maternal additive effects and endosperm additive effect for grain filling rate.