对供试的6个小麦品种进行小麦黑胚病调查统计.结果显示,6个品种均有小麦黑胚病发生,前后两代籽粒黑胚率分别为0.10％～21.10％和0.26％～25.22％,且不同品种间的发病程度存在差异.根据柯赫氏法则,分离所得主要病原菌为突脐蠕孢(Bi polaris sorokiniana)和细链格孢(Alternaria alternata),分离率分别为6.67％和76.67％；通过温室滴接试验,两种菌均能引起小麦黑胚病,突脐蠕孢和细链格孢的回接分离率分别为99.50％和96.67％,前者的致病力比后者强；小麦黑胚病的两种主要病原菌从扬花期至乳熟期均可侵染,以扬花盛期和灌浆初期为侵染的最适时期.%The results of investigation from 6 wheat varieties showed that all the wheat varieties had black point pathogen. The percentage of the black seeds was 0. 10% -21. 10% and 0. 26% -25. 22% separately between filial generation and offspring. The disease index was different among varieties. According to the Koch's postulates, the pathogens isolated from the wheat seeds mostly were B. Sorokiniana and A. Alternata, the percentage of separation was 6. 67% and 76. 67%. The result of dripping inoculation test in the greenhouse showed that B. Sorokiniana and A. Alternata both can cause black point of wheat, when we use these two pathogen return inoculated the wheat and isolated again, the isolation percentage of two pathogen B. Sorokiniana and A. Alternata was 99. 50% and 96. 67% , but the pathogenic degree of B. Sorokiniana v. As heavy than A. Alternata. At the same time, we concluded that the time of these two pathogens infecting wheat spike was very long, they can infect wheat spike from the stage of wheat flowering to rrilking, but the best infected time was the stage of flourishing flower and initial stages of grouting.
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