小麦纹枯病抗性QTL的SSR标记研究

SSR Markers Linked Resistance QTLs to Sharp Eyespot (Rhizoctonia cerealis) in Wheat

以ARz/扬麦158F6重组自交系(RILs)群体为材料,对其纹枯病抗性进行SSR分析和初步的QTL分析。群体抗性分析结果表明:纹枯病抗性是由多个基因控制的数量性状;单个标记方差及回归分析显示有6个SSR标记至少在2份抗性资料中能被检测到,涉及2D、3A、3B、3D、7D5条染色体,能解释2.6%～10.1%的抗性表型变异。标记Xgwm340来源于感病品种扬麦158,其余的SSR标记(Xgwm102、Xgwm155、Xgwm71-2、Xgwm645、Xgwm437)来源于抗病亲本ARz;利用MapManagerQTX软件进行QTL分析,检测到2个QTL。

This study was conducted to identify and locate the SSR markers for sharp eyespot resistance QTLs in ARz/Yangmai 158 RILs. The population of 137 lines was developed by SSD method from the cross of ARz (resistant) and Yangmai 158. Response to the R. cerealis was tested on the RILs from 2002 to 2003 at Nanjing in field using a toothpick and seed with Rhizoctonia cerealis inoculation method. 44 polymorphism SSR primers were analyzed on the population, and 47 loci were detected. Using regression analysis, 25 SSR markers linked to resistant QTLs were found based on three experiments. 6 SSR markers (located on five chromosomes respectively) of them were detected in two or three experiments, explained 2.6%-10.1% phenotypic variation (P<0.05). A major QTL linked SSR marker (Xgwm437) (located on 7D) explained 10.1% phenotypic variation (P<0.000()1). SSR marker Xgwm340 was from Yangmai 158, and the other SSR markers (Xgwm102, Xgwm155, Xgwm71-2, Xgwm645, Xgwm437) were from ARz. Quantitative trait loci(QTL) analysis was undertaken based on a constructed molecular linkage map (33 markers) of this population. Two resistance QTLs were identified,and located on chromosomes2D and 7D, respectively.