Missouri Southern State University, Joplin, MO 64801
Colletotrichum is an ascomycete fungus that causes anthracnose diseases on many crops worldwide and massive post harvest losses on cereals, legumes, vegetables, fruit, and ornamentals. Classification of Colletotrichum is based on physical appearance and pathogenicity on host(s). My study looked at four types of species classification for Colletotrichum from chili peppers worldwide. Classification techniques included morphology, molecular (VCGs), pathoginicity and genetic (DNA sequencing, mtDNA RFLPs). My analysis indicated that there are eight morphological groups. VCG testing indicates that 36 of 43 isolates of C. acutatum belonged to a single VCG (CA01). C. acutatum is more pathogenic on immature green fruit and less pathogenic on red mature fruit, C. gloeosporioides is more pathogenic on mature fruit than immature and C. capsici in mildly pathogenic to peppers. Isolates were placed into five RFLP groups based on the distribution of bands. Six atypical Colletotrichum isolates were found to be Nectria mauritiicola based on ITS sequencing. My results indicate that more than one species of Colletotrichum is active in pepper anthracnose and that the 36 isolates of C. acutatum are a single clone that has been distributed worldwide.
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