Ecology, Environment and Conservation Paper

FIRST REPORT OF FUNGAL PATHOGENS CAUSING POSTHARVEST CROWN ROT DISEASE IN BANANAS FROM COASTAL DISTRICTS OF ODISHA

Manasranjan Rout, Shyama Sundar Mahapatra, Sushree Suparna Mahapatra, Tapas Ranjan Das and Dibyajyoti Swain

Abstract

From March 2022 to February 2023, a study was carried out in the coastal districts of Odisha state to investigate crown rot disease samples, symptoms, and morphological traits of these pathogens in three banana varieties: Champa (AAB), Deshi patakpura (AAB), and G9 (AAA). Jajpur district had the highest disease incidence from March to June (2022) (Patakpura: 96%, G9:100%, Champa: 82%), whereas Mayurbhanj district had the lowest incidence between November and February (2022–2023) (Patakpura:18%, G9:22%, Champa:12%). Incidence of disease peaked in the summer, followed by the rainy season, and was minimal in the winter. Tissue blackening, softening, and a white mycelium or orange tinge beneath the crown’s surface were typical symptoms of crown rot. 4500 banana hands, 1230 crown fragments, and 474 fungal colonies were used in the investigation’s year-long data collection. Using cultural and morphological methods, these colonies were isolated, characterized, and identified, with Fusarium and Colletotrichum being the most prominent genera. Fusarium genera comprised 79.7% of the fungi that were identified, with Fusarium equiseti (37.3%), Fusarium verticillioides (35.4%), and Fusarium oxysporum (27.2%) among its species. Colletotrichum genera, as represented by 20.2% of the sample, was identified as Colletotrichum musae. White mycelia with orange pigmentation, slender macroconidia, and oval to obovoid-shaped microconidia lacking chlamydospores were all characteristics of Fusarium verticillioides. Fusarium equiseti colonies developed a russet coloration and included oval, hyaline microconidia and curved, hyaline macroconidia, and 2-5 septa with conspicuous foot cells. Fusarium oxysporum colonies initially produced white colour which changed to violet colour and produced fusiform macroconidia, 2-4 septa, and ellipsoidal to cylindrical microconidia. Both Fusarium equiseti and Fusarium oxysporum included chlamydospores. Black, acervulus-like masses, white to orange aerial mycelium, ellipsoidal aseptate conidia, and discernible oil globules were all present in Colletotrichum musae cultures.