籼粳稻杂交分类性状遗传研究初报

Preliminary Research on the Heredity of Classificatory Characters in the Hybridization Between Indica and Japonica

应用程氏指数法研究了不同类型杂交组合。结果表明：粳×籼Ｆ１为偏籼型，Ｆ２呈正态分布，大部分为籼粳中间型。粳×爪Ｆ１为偏粳型， Ｆ２为偏粳型和粳型。粳×粳Ｆ１与Ｆ２均为粳型。程氏指数法叶毛、稃毛、 穗壳色、ｉ～２穗节长、籽粒长宽比、酚反应６个分类性状间相关密切，对总分均有较大贡献，适于分析籼粳交Ｆ２以后各世代。粳×籼Ｆ２代各性状的分离除酚反应为双峰曲线外，其它５个性状均呈单峰曲线分布；除穗节长性状具有超亲现象外，其它５个性状均介于双亲之间，为部分显性。抽穗期与亲本及Ｆ１程氏指数呈极显著的负相关，结实率与Ｆ２程氏指数呈极显著的负相关。

In this study, the cross combinations of different type rice were classified by Cheng's index method. The results showed that F, from japonica-indica cross was indicaclinous and their F2 varied consistently, most of them were intermediate types, while those from japonica-javanica cross were japonicaclinous and their F2 were mainly japonicaclinous and japonica, and those from japonica-japonica cross were all japonicaclinous. Analysis of correlation showed that the six classificatory characters of Cheng's index method were closely correlated with each other and the method was suitable for analyzing the classification of F2. For the F2 from japonica-indica cross, the segregation of Phenol Reaction (PhR) character showed double-peak curve, whereas those of the other five showed single-peak curve distributions. The scores of the other five characters were all between their parents and partly dominant except the length of 1st & 2nd rachis (LOR) character. The date of heading was very significantly negatively correlated with Cheng's index of the parents and F1, so was the seed-setting rate with Cheng's index of F2.