玉米大斑病菌小种鉴别寄主综合抗性评价

Comprehensive Evaluation of Differential Hosts Resistance to Northern Corn Leaf Blight

以14份含有Ht1、Ht2、Ht3和HtN抗性基因的3套玉米大斑病菌小种鉴别寄主为材料,采用SNP基因芯片方法检测每套鉴别寄主的遗传背景相似度,用1,2,3,N号小种混合菌作为接种物,通过单叶病斑面积的发展速率评价含有Ht1、Ht2、Ht3和HtN基因的鉴别寄主综合抗性。结果表明：A619和OH43两套近等基因系内部遗传背景相似度最高,平均为98.86%和98.40%;B37近等基因系内部遗传背景相似度相对较低,平均为94.77%。接种后含有Ht2、Ht3抗性基因的鉴别寄主综合抗性最好,病斑发展速率为0.01~0.032,而CK和含Ht1、HtN基因的鉴别寄主抗性较差,病斑发展速率为0.112~0.216,推断这些鉴别寄主的抗病性差别是由抗性基因控制的。

Three set of 14 near isogenic lines（NILs） to northern corn leaf blight （NCLB） containing Htl, Ht2, Ht3 and HtN resistance gene were chosen as testing materials, the genetic background were tested by SNP gene chip. NILs were injected by mix races of exserohilum turcicum, the disease resistance were measured by the growth speed of lesions in single leaf. The results showed that the hosts containing Ht2 and Ht3 gene had better resistance than others. The developing rates of lessions to A619Ht2,A619Ht3, OH43Ht2, OH43Ht3, B37Ht2 and B37Ht3 were 0.012, 0.010, 0.032, 0.020, 0.027 and 0.024, respectively.