吉林省玉米苗病发生为害及病原真菌种类调查

A Study on Occurance of Corn Seedling Diseases and Spieces of Pathogenic Fungi in Jinn Province

近年来玉米苗期病害为害加重，一般发病率为１０％左右，感病杂交种发病率为２０％～３０％，少数重病地块发病率高达５０％以上。造成断苗断条，甚至毁种。经多年分离鉴定，致病菌主要有：串珠镰刀菌、禾谷镰刀菌、炭黑蠕孢菌、立枯丝核菌及腐霉菌。其中以串珠镰刀菌占优势，其次为禾谷镰刀菌和炭黑蠕孢菌，立枯丝核菌及腐霉菌极少。有的病苗由两种病原真菌复合侵染发病。

The occurance of corn seedling diseases increased in recent years. Generally,the disease incidence was asbout 10%, that of Susceptible hybrids 20-30%,in a fewsevere fields that up to more than 50%, which caused seedling missing and even plantdead. The pathoguns have been isolated and identificated for many years and it wasfound that the major pathogen were Fusarium moniliforme. F. graminearm,Bipolaria zeicola Rhizoctonia solani,Pythium spp, in which F. moniliforme was predominant,the second were F. graminearm and B. zeicola, R. solani and P. spp. only a few. Some of theseedling diseases were infected by mixture of two pathogenic fungi.