小麦品种川麦107对条锈病成株抗性的QTL定位

【目的】发掘川麦107中的条锈病成株抗性基因及与其紧密连锁的分子标记,为小麦持久抗性育种提供基因和分子标记辅助选择工具。【方法】在墨西哥国际玉米小麦改良中心(CIMMYT)Toluca试验站、中国成都和雅安3个环境下,对川麦107/Avocet-YrA组合的F5代重组自交系(recombinant inbred line,RIL)群体进行了小麦条锈病成株抗性鉴定,在此基础上利用SSR标记和复合区间作图法对成株抗性基因进行定位。【结果】在1B染色体长臂远端的Xcwem32和Xgwm818位点之间(连锁距离3.9cM)检测到1个主效QTL,暂定名为QYr.saas-1BL。该主效QTL在3个试验环境下分别解释19.3%、16.9%和27.4%的表型变异。【结论】QYr.saas-1BL是川麦107中对条锈病有持久抗性的成株抗性QTL。

QTL Mapping for Adult-Plant Resistance to Stripe Rust in Wheat Cultivar Chuanmai 107

Objective]The aim of this study was to identify adult-plant resistance gene to stripe rust in wheat cultivar Chuanmai 107 and the closely linked molecular markers, for breeding wheat cultivars with durable resistance.Method]A recombinant inbred line(RIL)population with 148 F_5 lines generated from the cross between Chuanmai 107 and Avocet-YrA(highly susceptible)were planted, together with their parents, in Chengdu and Ya'an, China and Toluca, Mexico during 2006 and 2007 cropping seasons for evaluating disease severities.A total of 940 SSR markers were used to screen two parents and the resistant and susceptible bulks, and subsequently the polymorphic SSRs between two bulks were used for QTL mapping based on composite interval mapping method.Result]A major QTL for adult-plant resistance to stripe rust was mapped on chromosome 1BL in the marker interval of Xcwem32-Xgwm818 with genetic distance of 3.9 cM.The QTL was tentatively designated QYr.saas-lBL.It presented resistance to yellow rust in all the three environments and explained 19.3%, 16.9%, and 27.4% of phenotypic variation at Toluca, Chengdu, and Ya'an, respectively.Conclusion]This major QTL is considered as a non-race-specific resistance locus in Chuanmal 107.