基于主基因+多基因混合模型的甜高粱茎秆含糖量基因遗传分析

Genetic Analysis of Stalk Sugar Content Using Mixed Major Gene Plus Poly-genes Model in Sweet Sorghum

笔者以茎秆含糖量(锤度)较低的粒用高粱品系LR625(P1)和茎秆含糖量(锤度)较高的甜高粱品系Rio(P2)及其杂交后代F1、F2群体为研究对象,运用主基因+多基因混合遗传模型对茎秆含糖量的遗传进行了联合分离分析。结果表明:茎秆含糖量性状受2对加性-显性-上位性主基因和加性-显性多基因共同控制。2对主基因的加性效应分别为-4.004和-2.116,显性效应分别为0.084和-0.462,主基因遗传力为83.27%,多基因遗传力为7.38%。这说明锤度性状主要受2对主基因的作用,而且2对主基因均以加性效应为主。这一研究结果为茎杆含糖量性状的基因定位和育种选择提供了理论依据。

The genetic segregation analysis of stalk sugar content（Brix） was made with the parents of LR625,a grain sorghum variety（P 1）,Rio,a sweet sorghum variety（P 2） and their F 1 and F 2 population using the mixed major gene plus poly-gene inheritance model.The results suggested that stalk sugar content（Brix） was controlled by two major genes with additive-dominant-epistatic effects and poly-genes with additive-dominant effects.The additive effects of the two major genes were -4.004 and -2.116 respectively,and the dominant effects of the two major genes were 0.084 and -0.426 respectively.The heritability of major genes was 83.27% and the heritability of poly-genes was 7.38%.This study indicated that the trait of stalk sugar content（Brix） was mainly affected by two major genes through additive effects.And the results can provide reference for QTL mapping and selection of stalk sugar content.