关键词: 籼型杂交水稻, 株高, 发育遗传, 杂种优势, 环境效应

Abstract: The developmental genetic rule of plant height was analyzed from two groups of three-line indica hybrid rice at two environmental conditions based on the NCⅡ design, using the additive-dominant developmental genetic models and the statistic methods. The results showed that the materials and environmental conditions both could affect plant height, and the effects of environment on plant height were decreased gradually with plant development. Additive and dominant effects both governed the performance of plant height at all developmental stages. However, the degree of effect varied with materials. Moreover, the interaction between environmental effects and genotypes also affected plant height. The genetic effects differed at most developmental stages. Furthermore the expression of additive effect was more active than that of dominant effect. Conditional interaction effects with environment also had some effects on plant height during genetic development, especially at the early stages. Mid-parent heterosis (H_MP) increased gradually with the developments stage of plant height, and maximized at the latest stage, whereas, heterosis over the better parent (H _BP) showed differences among the materials, and kept stable at the later stage, with positive numeric value. At most developmental stages, conditional H_MP was positively significant, while conditional H_BP was negatively significant. All above results showed that H_MP and H_BP had some new expression in all developmental periods and level and direction were quite different.

Key words: indica hybrid rice, plant height, developmental genetics, heterosis, environmental effect