Abstract:

Analysis of genetic main effects and genotype×environment (GE) interaction effects for brown rice weight (BRW) at four different filling stages in indica rice ( Oryza sativa L.) was conducted for two-year experimental data by using developmental genetic models and corresponding statistical approaches for quantitative traits of seeds in cereal crops. It was indicated that the genetic main effects and their GE interaction effects of triploid endosperm, cytoplasmic and diploid maternal plant genes were important for BRW at different filling stages of rice, especially for endosperm or maternal additive main effects and their additive interaction effects. Because of the higher additive effects and additive interaction effects for BRW at different filling stages, the better improving effects for this trait could be expected by selection in rice breeding. The results of conditional genetic variance components showed that the new expression of quantitative genes in endosperm and maternal plant for BRW was mostly found at all different filling stages of rice. The gene expression, however, was most active at the early filling stages especially for the first (1-7 d) and the second filling stages (8-14 d after flowering). The phenomena that some genes were spasmodically expressible among filling stages of rice were detected for some genetic effects especially for net cytoplasmic main effects or its interaction effects and net dominance main effects. Predicted genetic effects at different filling stages of rice showed that some parents such as V20 and Zuo 5 were better than others for improving the BRW.

不同环境下籼稻糙米重的发育遗传研究
石春海¹ 吴建国¹ 樊龙江¹ 朱军¹  吴平²

（1.  浙江大学农学系，杭州310029；2.  浙江大学生命科学学院，杭州310029）

摘要：采用包括遗传主效应和基因型与环境互作效应的数量性状发育传模型和统计分析方法，分析了籼稻（Oryza sativa L.）稻米4个发育时期糙米重的两年资料。结果表明，除了三倍体胚乳和二倍体母体植株基因的加性和显性主效应以及细胞质主效应可以控制不同稻米发育时期的糙米重量外，基因型与环境互作效应也可明显影响不同发育时期糙米重量。基因加性主效应和加性×环境互作效应在整个稻米灌浆过程中起着主要作用，对糙米重的选择可以取得良好的改良效果。条件方差分量分析结果表明，不乳和母体植株中控制行糙米重表现的基因在多数稻米发育时期均有新的表达，且以稻米发育早期为主，开花后第1－7天是控制糙米重的基因表达最为活跃的时期，其次为开花后第8－14天。一些基因只在个别发育时期间断表达，这在净细胞质主效应和净细胞质×环境互作效应以及净显性主效应上表现得尤为明显。稻米不同发育时期的遗传效应预测值表明，V20和作5等亲本可以明显提高后代的糙米重量。

Key words: indica rice ( Oryza sativa), developmental genetics, brown rice weight, genetic variances and conditional genetic variances, genetic effects