寒地粳稻粒宽在DH群体中遗传变异研究

Studies on Genetic Variation of Grain Width of Doubled Haploid Japonica Rice in Cold Region

为探索粒宽在寒地水稻在DH群体的遗传变异规律，笔者应用粒宽不同的3个亲本，采用F，花药培养技术构建了寒地水稻2个组合的DH（DoubledHaploid，DH）群体。应用Choo和Reibergs提出的模型及公式，分析了这2个DH群体粒宽的分布、测算了粒宽遗传力、超亲率，检测了粒宽的基因对数及基因互作方式。结果表明，水稻粒宽的遗传变异分为两种遗传模式，第一种遗传模式为主效基因加微效多基因混合数量遗传；无主效基因互作。第二种遗传模式为多个主效基因加微效多基因混合数量遗传，主效基因间存在互作，为互补作用；粒宽在DH群体的遗传力为0．61；控制粒宽的基因为7．5～12_3对、平均9．9对。因此，在寒地花培品质育种中有目的对粒宽进行低世代严格选择，对提高粒重及选育适宜粒型的优异种质是十分有效的。

In this study, the DH population of 2 combinations had been constructed in cold rice region by the technology of anther culture in hybridization combination F~ which from 3 parents of different grain width, in or- der to define the hereditary variation distribution of grain width in DH population. We estimated hereditary ca- pacity and rate over parent in DH population by the model and formula which were presented by Choo and Rei- bergs, and examined the number of gene pairs and the pattern of gene interaction which controlled these charac- ters. The results showed that the hereditary variation of grain width was divided into two models： Model I was mixed quantitative heredity which was controlled by major gene and many minor genes; there was no interac- tion of major genes. Model II was mixed quantitative heredity controlled by many major genes and many minor genes, there was effect among major genes, which was complement each other. The hereditary capacity of grain length was 0.61, and the number of gene pairs was 7.8-12.3 pairs controlled by grain length, 9.9 on average. As a result, strictly choose grain width individual of low generation was very effective for germplasm innovation, such as improving grain weight and breeding suitable grain types in quality breeding of anther culture in cold rice region.