黑龙江玉米大斑病菌生理分化研究

用常规鉴别寄主鉴定方法对2005年和2006年采自黑龙江省玉米主产区的48个大斑病菌菌株进行生理分化鉴定。结果表明，在黑龙江玉米产区鉴定出0、1、12、13、23N、123共6个生理小种。黑龙江玉米大斑病菌以0号生理小种为主，所占比例为52.08%；但其他小种有上升为优势小种的趋势，如1、12、13号小种所占比例分别为22.92%、10.42%和8.33%。说明黑龙江玉米产区玉米大斑病菌生理分化组成已发生变化，并且出现了克服多个抗性基因的生理小种，小种毒性组成呈复杂化。

Identification of Physiological Races of Setosphaeria turcica in Northeast Corn Region of Heilongjiang

Using different resistant genes(Ht1, Ht2, Ht3 and HtN) as differential hosts 48 isolates of Exserohulum turcium, collected from Heilongjiang in 2005 and 2006. The results showed that 6 physiological races including 0, 1, 12, 13, 23N, 123 were found, the races with higher frequency were race 0, about 52.08% respectively of the total isolates collected. However, other physiological races have advantage for the rise in the trend of species, such as 1, 12 and 13 physiological races account for the proportion of 22.92%, 10.42% and 8.33%. The corn-producing areas in Heilongjiang composition of physiological race of Exserohilum turcicum had changed, and appeared had overcome many resistant genes the physiologic races, the physiological race of toxicity composition had presented the complication.