天水地区小麦白粉病菌致病类群初步测定

1987～1989年,对甘肃天水地区的小麦白粉病菌致病类群,用鉴别寄主品种进行了室内测定和田间自然感染监测。结果表明,有11个致病类群,三年结果基本一致,没有明显变化。优势类群(015,011)的频率在48.1％～67.9％,它们是弱致病类群,但对生产上的品种,大部分能侵染。供试的菌样对鉴别寄主品种的毒性频率为:阿夫,100％;Ulka×Cc8(Pm2),22.4％;Era,55％,高加索(Pm8),100％;CI12633(Pm2+Pm6),14.3％;Maris Huntsman (Pm2+Pm6),14.3％;肯贵阿,2.5％;白免3号(Pm2x),12.3％;新疆小白冬麦,0.0％。另外,对洛夫林10的毒性频率100％,对Khapli(Pm4等)免疫。

Preliminary Differentiation on Pathogenic Groups ofWheat Powdery Mildew Fungus (Blumeria graminis f.sp.tritici) in Tianshui Area

In the years of 1987-1989, isolates of Blumeria graminis f. sp. tritici (Erysiphe graminis f. sp. tritici) from Tianshui area were differentiated with differential hosts in laboratory, and natural infection to differential hosts was detected in the field. The results indicated that the isolates were divided into 11 pathogenic groups and that results of three years were basically the same without any apparent changes. Frequency of the major groups(015, OlOwere 48.1%-67.9% and they are the weak groups in virulence, but it can affect most cultivated varieties. Frequency of virulence of the pathogen to Afu, kavkaz (Pm8) and lovrin 10 were 100%, 55% to Era, 22.4% to UlkaxCcS (Pm2) , 14.3% to CI12633 and Maris Huntsman (Pm2 + Pm6) , 12.3% to bai mian 3 hao (Pm2x) ,2.5% to kenguia and 0.0% to xinjiang xiao bai dong mai. Khapli (Pm4a) was immune to the all isolates.