小麦品种Libellula和咸农4号数量抗条锈病的抗性组分遗传研究

Components inheritance of quantitative resistance to stripe rust in wheat cultivars,Libellula and Xiannong 4

为明确小麦对条锈菌(Puccinia striiformisWest.f.sp.tritici)数量抗性的几个抗性组分的遗传,并确定有效的抗性组分,对Libellula和咸农4号杂交组合的7个世代进行了组织病理学和培养性状观察;运用遗传估计、通径分析和联合尺度检验的方法进行遗传力、显性度和基因数的估计,以及组分间的因果关系和基因互作方式的探讨。发现菌落长度和宽度的遗传力较高,分别为0.79和0.57,而显性度很低,分别为0.02和0.11;两者对菌落面积建成的直接效应分别为0.55和0.40,间接效应分别为0.45和0.32,远大于其他组分的直接和间接效应;尺度检验只有控制菌落长度和宽度的抗病基因才符合加性(m[d])模型。因此,在5个抗性组分中,菌落长度和宽度可以作为有效的选育抗性材料的抗性组分,同时筛选工作大大提高了抗性材料的选育和基基标记的效率。

In order to determine the components inheritance of quantitative resistance to stripe rust and the useful components in two wheat cultivars, seven populations derived from a cross of Libellula and Xian nong 4 which have resistance to Puccinia striiformis West. f. sp. tritici, were studied histopathologically. Heritability, degree of dominance and number of genes were estimated for these characters using genetic estimation. Causality of components and gene action of resistance were also studied using path analyses and joint scaling test. We found that colony length and width had higher heritability （0.79 and 0.57） and lower degree of dominance （0.02 and 0.11）. The direct effect of the two components on the area of colony were 0.55 and 0.40 while the indirect effects were 0.45 and 0.32 respectively. These effects exceeded those of the others and only the two components fit the m[d] models, These results indicate that the length and width of colony could be useful among the five resistant components in breeding.