CIMMYT小麦材料Kundan条锈病成株抗性QTL的定位与效应鉴定

QTL Mapping and Characterization of Stripe Rust Adult Plant Resistance in CIMMYT Wheat Cultivar Kundan

小麦条锈病是严重影响中国小麦产量的主要病害之一,利用成株抗性是小麦抗病育种的重要方向。本研究利用国际玉米小麦改良中心(centro internacional de mejoramientode maizy trigo,CIMMYT)引进的条锈病成株抗性品种Kundan和易感品种Avocet构建而成的131株群体大小的重组自交系群体来研究小麦条锈病成株抗性遗传基础。通过小麦50K DArT-Seq基因芯片技术完成131重组自交系群体的基因分型,经筛选获得了1 293个DArT-Seq标记,构建了分布于21条染色体上的22个连锁群,总长度为1 715.934 cM,两标记间的平均距离为1.34 cM。A、B和D基因连锁群长度分别为809.379 cM、674.469 cM和232.086 cM。连续两年在四川绵阳调查成株期抗性表型鉴定,利用复合区间作图法鉴定出一个位于染色体1BL上的抗条锈病主效基因QTL,位于标记G1107928与G1121552之间,遗传距离为5.5 cM,解释表型变异14.8%~18.8%,发现该基因不同于1BL上其他抗条锈病基因,具有成株抗性,为该基因的分子辅助选择和遗传利用提供了依据。

Stripe rust is one of the major diseases that seriously affect wheat production in China.Utilization of adult plant resistance is an important direction of wheat breeding for disease resistance.In this study,the genetic basis of adult resistance to stripe rust was studied using a 131 recombinant inbred lines population constructed by the adult resistance cultivar Kundan and susceptible cultivar Avocet,that introduced from CIMMYT.Wheat 50K gene chip technology was used to complete the genotyping of the recombinant inbred lines.Finally,1293 DArT-Seq markers were obtained,22 linkage groups were constructed distributed on 21 chromosomes,the total length is 1715.934 cM,the average distance between two markers is 1.34 cM,the lengths of the A,B,and D gene linkage groups were 809.379 cM,674.469 cM,and 232.086 cM,respectively.We executed disease resistance evaluation at adult plant stage for two consecutive years.Inclusive composite interval mapping identified a major YR QTL on chromosome 1BL.Between markers G1107928 and G1121552,the genetic distance is 5.5 cM,contributed 14.8%to 18.8%of YR variations.The new gene was found to be different from other stripe rust genes on 1BL,provides usable gene for the development of new varieties that possess adult plant resistance.