Biology, pathology, and management of Colletotrichum musae and perspectives on developing anthracnose-resistant crop varieties

Abstract

Colletotrichum musae, initially described as Myxosporium musae, is the fungus responsible for pre- and post-harvest banana anthracnose. On banana fruits, the fungus causes sunken lesions, which turn into sunken, dark patches with orange acervuli as the fruit ripens. In the field, the pathogen also causes crown rot that attacks the deciduous flowering parts of the banana, leading to fruit and peel necrosis. Colletotrichum musae can be easily isolated from the infected tissue and grown in potato dextrose agar medium. Serological assays, molecular methods, biosensors, machine learning, and artificial intelligence-based approaches can also achieve detection and identification. The infection process of C. musae in banana involves rapid spore germination and appressorium formation in its host under favorable conditions, which include high relative humidity, temperatures ranging from 25 to 30 °C, and a neutral pH. Colletotrichum musae causes a latent infection in immature fruits, with symptoms gradually developing as the fruits ripen. This “quiescent anthracnose” phase remains unnoticeable, and the fungus remains dormant in the subcuticle until fruit maturation. Management strategies for banana anthracnose caused by C. musae focus on preventing infection and slowing symptom development. They encompass cultural, chemical, natural products, biological, and genetic resistance of the host, and their combinations. This paper reviews the current understanding of the biology, pathology, and management of banana anthracnose caused by C. musae. This paper also discussed a general framework for improving crop varieties for anthracnose resistance. Anthracnose management often involves chemical control, which can lead to the development of fungicide resistance and pose environmental and health risks. Thus, resistant varieties are the most sustainable and viable options for managing anthracnose in the integrated disease management approach.