1999年我国小麦叶锈菌毒性监测

采用国际通用的小麦叶锈菌鉴别寄主和辅助鉴别寄主分析了来自1999年我国不同地区小麦叶锈菌的毒性基因,479个叶锈菌株共划分为162个毒性类型,其中23个为主要毒性类型.毒性类型中出现频率最高的为FHB、PHT、FHG、THT,它们对抗叶锈基因Lr2a、Lr2b、Lr3、Lr10、Lr14b、Lr16、 Lr26的平均毒性频率高于80%,而对Lr3ka、Lr25、Lr19、Lr24、Lr30、Lr15、Lr35的平均毒性频率低于30%;发现对Lr35有毒力的菌株,出现频率为1.04%;至今尚未发现对Lr38、Lr45抗性基因有毒力的菌株.研究同时发现,不同地区小麦叶锈菌的毒性类型不同,毒性频率存在一定的差异.Lr9、Lr15、Lr19、Lr24、Lr35、Lr38、Lr45为小麦抗叶锈育种可利用的有效抗病基因.

Virulence of Puccinia triticina on wheat in China in 1999

479 urediniospore isolates of Puccinia triticina obtained from main wheat growing regions in China in 1999 were tested by using near-isogenic lines in thatcher background of wheat leaf rust resistance as differentials.162 pathotypes were found among 479 single uredinal isolates in 1999.The prevalence pathotypes in 1999 were FHB,PHT,FHG and THT.Virulence frequency was above 80% to genes Lr2c,Lr2b,Lr3,Lr10,Lr14b,Lr16 and Lr26 below 30% to Lr3ka,Lr25,Lr19,Lr24,Lr30,Lr15 and Lr35.New isolate virulent to Lr35 was detected in 1999 that had not being detected before,and the virulence frequency was only up to 1.04%.No virulence isolate was found to Lr38 and Lr45.Different pathotypes and virulence frequency were found in different wheat growing regions in 1999 as before.Lr9,Lr15,Lr19,Lr24,Lr35,Lr38 and Lr45 are more potential resistance genes to wheat leaf rust in wheat resistance breeding program.