小麦品种中梁21抗条锈病基因遗传分析与SSR标记定位

摘要

Wheat cultivar Zhongliang 21 displayed resistance to epidemic yellow rust races in China when tested with seven races oiPuccinia striiformis f. Sp. Tritici (Psi). To use the elite resistance to Pst in wheat breeding, we identified the resistance gene (s) in Zhongliang 21 by means of phenotypic evaluation and molecular marker technique. Seedlings of the F1, F2, and BQ generations from the cross between Zhongliang 21 (resistant) and Mingxian 169 (susceptible), as well as the parents, were tested with Pst race CYR30. The results showed that the stripe rust resistance in Zhongliang 21 was conferred by a single dominant gene, which was designated YrzhongH, temporarily. Ten simple sequence repeat (SSR) markers located on chromosome arm 5AL, Xgwml86, Xbarcl65, Xwmc795, Xbarc40, Xgwml56, Xgwm617, Xwmc415, Xbarcl51, Xwmc338, andXgwm666, were linked to YrzhongH with the nearest flanking markers ofXgwml86 andXbarc!65. The genetic distances were 7.5 cM toXgwml86 and 2.7 cM toXbarcl65. Based on chromosomal location, reactions to various pathotypes and pedigree analysis, we deduced YrzhongH is a novel resistance gene to stripe rust. Eighteen cultivars (lines) of Zhongliang series were tested with the flanking markers Xgwm 186 and Xbarc 165, and only 17% showed the same banding pattern as that in Zhongliang 21. This result suggested that 17% of Zhongliang cultivars (lines) might carry YrzhongH, indicating that this resistance gene has a potential application in wheat breeding program for strip rust resistance.%用7个我国当前流行的条锈菌生理小种评价中梁21的苗期条锈抗性,结果表明该品种对我国优势流行小种具有良好的抗性.采用CYR30小种对中梁21与铭贤169杂交的F1、BC1、F2及F3代群体进行遗传分析,并利用SSR分子标记进行遗传作图,发现中梁21对CYR30的抗性由1个显性基因控制,暂命名为Yrzhong21.该基因与位于小麦5AL染色体上的10个SSR位点Xgwm186、Xbarc165、Xwmc795、Xbarc40、Xgwm156、Xgwm617、Xwmc415、Xbarc151、Xwmc338和Xgwm666连锁,其中最近的侧翼位点为Xgwm186和Xbarc165,其遗传距离分别是7.5cM和2.7cM.系谱分析及结合分子标记结果表明,该基因可能来自Ciemenp.与已定位于5A染色体上的抗条锈病基因的比较表明,Yrzhong21可能是一个抗条锈病的新基因.用标记Xgwm186和Xbarc165检测中梁系列品种,其中仅17%扩增到与中梁21相同的位点,表明该基因在抗条锈病育种中可能有很大的应用潜力.