Diversity of Colletotrichum gloeosporioides Causing Anthracnose on Plum Trees in Wuhan

Wuhan is the global research and resource center of the plum(Prunus mume).Anthracnose is an important plant disease of the plum.In this study,170 fungal isolates were isolated from plum leaves showing anthracnose symptoms collected from Wuhan,Hubei Province.The isolates were classified into seven types based on colony morphology,pigment production,morphology and size of spore conidia and conidiophore.Isolates of all types could infect Rosaceae fruit trees,but could not infect plant species belonging to other tested families.Pathogenicity differed among the isolates on different species of fruit trees in the family Rosaceae.Isolates of all types were identified as Colletotrichum gloeosporioides based on ITS sequence,although there was great diversity on biological characteristics and pathogenicity.RAPD analysis indicated great genetic diversity among 36 isolates selected from the seven types.Dendrogram analysis showed that they were divided into three groups when the similarity level was 55%.The three-group classification was not consistent with the seven-type classification,or with the pathogenicity.These results suggest that isolates of C.gloeosporioides from the plum showed great diversity on biological and genetic characteristics.