水稻功能叶性状的遗传分析

Genetic Analysis on Characters of Functional Leaves in Rice

以籼型水稻13个不育系和19个恢复系为材料，按NCⅡ交配设计配制两套杂交组合（7×10和9×9），在四川泸州和重庆北碚两个不同的生态环境下，研究水稻剑叶、倒2叶和倒3叶的遗传特征。剑叶宽、倒2叶长和宽、倒3叶长的遗传变异是由加性和显性效应共同引起的，但叶宽是加性效应占主导地位，而叶长则以显性效应为主，剑叶长的遗传变异主要由显性效应引起，倒3叶宽的遗传变异则主要由加性效应引起。功能叶各性状的加性效应与环境互作不显著，而叶长的显性效应与环境互作均达到显著或极显著水平。两套组合中叶宽的狭义遗传率均大于叶长，其中最大的是倒2叶宽，分别为58．65％和48．19％。叶长和叶宽均表现出不同程度的中亲优势或负向超亲优势，其中，叶长和叶宽的中亲优势率变幅为4．46％（倒3叶宽，第1套）～27．53％（倒3叶长，第2套），而6个功能叶性状的杂种优势指数则均大于100％。

Genetic characterization of functional leaves of rice （Oryza sativa L. subsp, indica）, including flag leaf, the 2nd leaf from the top and the 3rd leaf from the top, was conducted based on diallel cross data（7× 10 and 9 ×9） with 13 sterile lines and 19 restorer lines by the NC Ⅱ design. The F1 and parents were planted at Luzhou, Sichuan and Beibei, Chongqing with a randomized block design and three replications. The results showed that the genetic variances of the flag leaf width, the length and the width of the 2nd leaf from the top, and the length of the 3rd leaf from the top were led by both additive and dominant effects, in which the genetic variances of the leaf width were mainly led by additive effects while those of the leaf length were mainly led by dominant effects. The genetic variance of the flag leaf length was primarily led by dominant effect, while the width of the 3rd leaf from the top was only led by additive effect. The dominant effect and environmental effect interaction of the length of the functional leaves were significant at 5% or 1% level, while the additive effect and environmental effect interactions of the width of the functional leaves were not significant. Narrow heritability （hN） of the leaf width was generally higher than that of the leaf length in the two sets of combinations, in which hN of the width of the 2nd leaf from the top was the highest, with 58.65% and 48.19% respectively in the two sets of combinations. The length and the width of functional leaves in rice exhibited mid-parent heterosis or negative over-parent heterosis at vari ous degrees, in which the mid-parent heterosis ranged from 4.46% to 27.53%, and the indexes of heterosis of the leaf width and length all exceeded 100%.