Identification and Characterization of Colletotrichum Isolates Obtained from Various Horticultural Crops in Central Hokkaido

Abstract

We collected 11 Colletotrichum isolates from various horticultural crops, i.e., apple, grape, cherry, blueberry, watermelon and eustoma, exhibiting anthracnose symptoms in central Hokkaido from 2006 to 2016. Species-specific polymerase chain reaction (PCR) analyses revealed that all 11 isolates belonged to the Colletotrichum acutatum species complex (CASC). Based on partial nucleotide sequences of the β-tubulin-2 gene, we identified seven isolates from grape, apple, watermelon, blueberry and cherry, two isolates from eustoma and blueberry and two isolates from apple and cherry as C. nymphaeae, C. fioriniae, and C. godetiae, respectively. In the present study, we described the morphology of the conidia, appressoria and reverse colony colors of the isolates. All of the 11 isolates caused soft rot in apple fruits. The present study reveals that CASC is widespread in central Hokkaido.