Identification, characterization and pathogenicity of Colletotrichum asianum, C. fructicola, and C. laticiphilum causing mango anthracnose in Vietnam

Abstract

Mango (Mangifera indica L.) is famous for its flavor, aroma, and nutritional value. However, anthracnose caused by Colletotrichum is the most destructive postharvest disease of mango, causing significant economic losses. This study aimed to identify and characterize Colletotrichum species associated with mango anthracnose in Vietnam and evaluate their pathogenicity and cross-infection potential. Through examination of colony characteristics, conidia, and appressorial morphology, along with phylogenetic analysis based on the ITS region and five genetic markers (gapdh, act, tub2, chs-1, and cal), five isolates were classified into three distinct species: C. asianum (MH32, MH24, and MC76), C. fructicola (MC32), and C. laticiphilum (MC81). Notably, C. fructicola and C. laticiphilum are the two species identified for the first time on mangoes in Vietnam. Pathogenicity tests demonstrated that C. fructicola MC32 and C. laticiphilum MC81 caused anthracnose in mango, banana, guava, and tomato. Among the C. asianum isolates, differences in aggressiveness were observed: isolate MH32 caused anthracnose on mango, banana, guava, and tomato; isolate MC76 caused anthracnose on mango, banana, and tomato; and isolate MH24 affected only mango and tomato.