Abstract: Nine cytoplasmic male sterile lines and five restoring lines were used in an incomplete diallel cross for analyzing genetic correlations of nutrient quality traits(protein content,protein index, lysine content, lysine index and the ratio of lysine content to protein content) of milled rice in indica rice(Oryza sativa L.). The results indicated that the genetic correlations of seed, cytoplasm and/or maternal plant are responsible for genetic correlations of most pairwise nutrient quality traits. The seed additive and dominance correlations, cytoplasmic correlations, maternal additive and dominance correlations for most pairwise traits studied were significantly positive. Some of the pairwise traits had negative genetic correlations especially for the traits between nutrient quality traits and the ratio of lysine content to protein content. Indirect selection for those traits with additive correlations was better than with dominance correlations. But the dominance correlations could be effectively used in hybrid rice breeding. The cytoplasmic correlations could be applied in both conventional crossing breeding and hybrid rice breeding.

Key words: genetic correlations, indica rice, nutrient quality

摘要： 利用9个籼型不育系和5个籼型恢复系进行不完全双列杂交，同时分析了早籼稻米蛋白质含量、蛋白质指数、赖氨酸含量、赖氨酸指数以及赖氨酸含量与蛋白质含量的比值等营养品质成对性状间种子、细胞质和母体等多种遗传相关。结果证实蛋白质含量与蛋白质指数等多数成对性状间的种子加性和显性相关、细胞质相关以及母体加性和显性相关系数均为显著正值，对这些性状进行间接改良有效。但赖氨酸含量与蛋白质含量的比值同蛋白质性状的关系则以显著负相关为主，表明选择高蛋白质含量或蛋白质指数的单株将会显著降低该比值。正向的种子和母体显性相关以及细胞质相关可以同时显著提高杂交稻组合中赖氨酸含量和赖氨酸指数以及赖氨酸含量与蛋白质含量比值。对于主要受加性相关控制的成对性状进行间接选择具有较好的效果，而杂交稻育种中则以利用显性相关为主。

关键词: 遗传相关, 营养品质, 籼稻