甘蓝型油菜DH群体抗裂角性的遗传分析

提高抗裂角性是培育适合机械化收获油菜品种的基本要求。为了明确油菜抗裂角性的遗传规律,本研究利用抗裂角性差异显著的两个甘蓝型油菜品系配制杂交组合,通过小孢子培养构建了一个双单倍体(doubled haploid,DH)群体。采用随机碰撞法对该群体进行连续两年的抗裂角性鉴定,并利用植物数量性状的主基因+多基因混合遗传模型及偏度和峰度分析对抗裂角性进行遗传分析。结果表明,甘蓝型油菜的抗裂角性受3对主基因+多基因控制,涉及的基因数目为8~10对,存在基因的加性效应及基因间的互补作用;两年试验中抗裂角性的主基因遗传率均大于85.00%,主基因遗传率较高,表明该性状主要受主基因控制,受其它微效多基因及环境的影响有限。因此,在油菜抗裂角性遗传改良中,应通过杂交聚合不同抗性等级材料中的主效抗裂角基因,在早期世代加强对抗性的选择,并可以忽略环境因素的影响。

Inheritance of pod shatter resistance using a DH population in Brassica napus L.

Improvement of pod shatter resistance is the basic target for rapeseed breeding suitable for mechanized harvesting. To better understand the inheritance of pod shatter resistance in Brassica napus, a doubled haploid (DH) population was used in the study. Two parents of the population had contrasting pod shatter resistance levels. Pod shatter resistance index was determined using random impact test method in two years, and the inheritance was analyzed by major gene plus polygene genetic model for plant quantitative traits as well as the analysis of skewness and kurtosis. Results showed that the pod shatter resistance was controlled by 3 genes with major effects and 5-7 polygenes with minor effects. There were major genes additive effects and complementary gene interactions. The heritability of major genes was greater than 85.00% in both years, indicating pod shatter resistance was mainly controlled by major genes and less influenced by environments. Therefore, in breeding process for pod shatter resistance of rapeseed, pyramiding major genes from lines containing different major genes by hybridization and selection in early generation should be considered, and the influence of environmental factors can be ignored.