普通小麦白粉病成株抗性的QTL分析

QTL Mapping for Adult-Plant Resistance to Powdery Mildew in Bread Wheat

以抗白粉病的日本小麦品种Fukuho-komugi和以色列小麦Oligoculm杂交F1的DH(doubled haploid)群体107个系为材料,利用313个SSR标记和37个RFLP标记,对Fukuho-komugi和Oligoculm的白粉病成株抗性进行QTL分析。试验材料于2003—2004年度种植在北京2、003—2004和2004—2005年度种植在安阳,调查白粉病发病情况。构建了由350个位点组成的遗传连锁图,覆盖小麦21个连锁群,全长3 101 cM。采用复合区间作图法进行白粉病成株抗性QTL分析,在1A、2B4、B和7D上发现4个抗白粉病QTL,分别解释13.6%、6.6%、8.9%和12.7%的表型变异。抗白粉病基因及其紧密连锁分子标记的发掘,将为小麦抗白粉病育种的分子标记辅助选择提供理论和技术支持。

Powdery mildew, caused by Blumeria graminis f. sp. tritici, is a major wheat disease in China. Use of adultplant resistance is an effective method to develop wheat cultivars with durable resistance to powdery mildew. In the present study, a total of 313 SSR and 37 RFLP markers were used to map QTL for adult-plant resistance to powdery mildew in a DH population with 107 families derived from the cross Fukuho-komugi × Oligoculm. Field trials were conducted in Beijing in 2003-2004 crop season, and in Anyang, Henan Province in 2003-2004 and 2004-2005 crop seasons, respectively. The DH families were planted in a randomized complete block design with 3 replicates. Artificial inoculation was carried out in Beijing with highly virulent isolate E20 of Blumeria graminis f. sp. tritici and the powdery mildew severity on penultimate leaf was evaluated for 5 times. The maximum disease severity on penultimate leaf was scored in Anyang under natural inoculation around May 18, 2004 and 2005. Linkage analysis indicated that the genetic map consisting of 313 SSR and 37 RFLP markers covered 21 wheat linkage group with a total genetic distance of 3101 cM. With the method of composite interval mapping （CIM）, 4 QTLs for adult-plant resistance to powdery mildew were detected on chromosome 1A,2B,4B and 7D, explaining 13.6% ,6.6% ,8.9% and 12.7% of phenotypic variance, respectively. Three QTLs on chromosome 1A, 2B, and 7D were derived from the female parent Fukuho-komugi, while the one on chromosome 4B was from the male Oligoculm. The QTL on chromosome 1A showed high genetic effect for powdery mildew resistance across two environments.These results are essential for marker-assisted selection for improving powdery mildew resistance in wheat breeding programs.