为明确黑龙江省玉米丝黑穗病病菌致病性及遗传分化,应用人工接种和RAPD技术进行了试验。结果表明,按致病性将12个玉米丝黑穗病菌分为3个反应型,但差别较小,仅存在致病力差异,不存在致病性分化;相异系数在0.48水平上,将12个菌株分为3个遗传类型,有优势类型存在。说明两种鉴别体系存在着一定相关性且都与地域差异密切相关。 In order to clarify the pathogenicity and genetic differentiation of maize head smut in Heilongjiang Province, experiments were carried out by artificial inoculation and RAPD techniques. The results showed that according to the pathogenicity, 12 maize head smut were divided into three reaction types, but the difference was small with only difference in pathogenicity and no pathogenic differentiation. The coefficient of variation was 0.48 Twelve strains were divided into three genetic types, there are dominant types exist. This shows that there are some correlations between the two kinds of identification systems and are closely related to the geographical differences.