Identification and characterisation of Colletotrichum fructicola, C. tropicale and C. theobromicola causing mango anthracnose in the Philippines

Mango (Mangifera indica L.) is widely grown in the Philippines. It is very susceptible to several pre- and post-harvest diseases, with Colletotrichum as one of the most important fungal pathogens worldwide. This study aims to characterise the Colletotrichum species associated with mango anthracnose in the Philippines through combined morphological and molecular approaches. A total of 58 isolates were obtained from the anthracnose-infected leaves collected from 11 provinces in the Philippines. Thirty isolates were used for sequence analyses of the actin, glyceraldehyde 3-phosphate dehydrogenase, and beta-tubulin gene regions. Phylogenetic analyses and morphological characterisation revealed the identity of the anthracnose pathogens as C. fructicola, C. tropicale, and C. theobromicola. All isolates caused anthracnose symptoms in mango leaves (cv. Carabao) in pathogenicity assays, hence, Koch's postulate was established. This study is the first scientific report of C. fructicola, C. tropicale, and C. theobromicola as mango anthracnose pathogens in the Philippines.