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 (2022ââ¬â2023) (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 crownââ¬â¢s surface were typical symptoms of crown rot. 4500 banana hands, 1230 crown fragments, and 474 fungal colonies were used in the investigationââ¬â¢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.