吉林省玉米大斑病菌生理小种的组成变异与动态预测

通过1套鉴别寄主对2006～2007年采自吉林省7个地区100份玉米大斑病病菌分离物的致病性进行分析。结果表明,共鉴定出15个类型的生理小种:0、1、2、3、12、13、1N、23、2N、3N、12N、13N、123N、123、23N;吉林省玉米大斑病菌的小种组成十分复杂,在中晚熟玉米产区已没有明确优势小种的存在;1号生理小种虽然是主要小种类群,但所占比例仅为18%,并且出现了能够克服4个抗性基因的强毒力小种。不同玉米熟区的大斑病生理小种的分布与种间变异频率也趋于复杂。

The Composition Variation and Dynamic Forecast of Exserohilum turcicum Race Physiological Variation in Jilin Province

Using routine technique,one hundred isolates of Exserohihun turcicum,collected from 7 farming areas of Jilin province from 2006 to 2007,were identified in pathogenic variation to different Ht resistance gene by the group of hosts.The results showed that 15 physiological races including 0,1,2,3,12,13,1N,23,2N,3N,12N,13N,123N,123,23N were found.It was quite complex race component in Jilin province,and there were not dominant races as well as in mid-serotinous production areas of maize.Race 1 was also the main races but its frequency was only about 18% respectively.The virulence of the race 123N was so stronger that it could infect all the maize with single Ht gene.Races of Exserohihun turcicum distribution and interspecific variability in different maturity corn varieties areas also became complex.