Genetic Diversity of Colletotrichum spp. Causing Strawberry Anthracnose in Zhejiang, China

Anthracnose is a serious fungal disease that primarily infects strawberry roots and stolons during development. Here, 91 isolates from different areas of Zhejiang province, China, were collected. Morphological characteristics were analyzed, and a phylogenetic analysis based on multiple genes (actin, internal transcribed spacer, calmodulin, glyceraldehyde-3-phosphate dehydrogenase, and chitin synthase) was performed. We found that all of the Colletotrichum species causing strawberry anthracnose belonged to the Colletotrichum gloeosporioides complex. Among them, we identified 48 isolates of C. fructicola, 21 isolates of C. siamense, 13 isolates of C. gloeosporioides, and 9 isolates of C. aenigma. C. siamense was distributed in the central and eastern regions of Zhejiang province (Hangzhou, Jinhua, Shaoxing, Ningbo, and Taizhou). This is the first report of C. siamense causing strawberry anthracnose in Zhejiang province. C. fructicola was the most dominant species causing strawberry anthracnose in Zhejiang province. We identified the four species causing strawberry anthracnose in Zhejiang province, which will improve our understanding of the strawberry anthracnose epidemic and will benefit the development of future control measures.

Molecular and Morphological Characterization of Colletotrichum Species in the Colletotrichum gloeosporioides Complex Associated with Persimmon Anthracnose in South Korea

Anthracnose is a major disease of persimmon in the pre- and postharvest phase. Several species of Colletotrichum (Colletotrichum gloeosporioides, C. acutatum, and C. horii) have been reported as causal agents of persimmon anthracnose in South Korea. In this study, a collection of 50 isolates associated with persimmon anthracnose were collected from Sangju (n = 25) and Cheongdo-gun (n = 25), South Korea. The morphological characteristics of all 50 Colletotrichum isolates were similar, and it was difficult to identify the isolates to the species level. A subsample of eight isolates was characterized phylogenetically to ascertain species. BLAST search and phylogenetic analysis of the internal transcribed spacer (ITS), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and actin (ACT) genes revealed two species: C. horii as well as a previously unreported persimmon anthracnose causal agent C. siamense. C. siamense isolates were confirmed again by phylogenetic analysis of the ITS, ACT, GAPDH, calmodulin, and Apn2-Mat1-2 intergenic spacer partial mating type genes. Koch’s postulates for C. horii and C. siamense were fulfilled, confirming the pathogenicity of the two species in persimmon fruit. Morphological characteristics (colony morphology and size and shape of conidia and appressoria) from two representative isolates support results of the phylogenetic analysis and match those of previous descriptions of C. horii and C. siamense.