Caracterização de isolados de Colletotrichum sp. extraidos da banana (Musa sp.)

Abstract

The genus Colletotrichum comprises phytopathogenic fungi that are widely distributed globally and of great agricultural importance, causing diseases that result in significant losses in various crops, particularly bananas (Musa sp.). Morphological characterization of these fungi is a crucial step in understanding their biological behavior and supporting studies related to their identification and management. In this context, the present study aimed to morphologically characterize Colletotrichum sp. isolates obtained from banana fruits exhibiting anthracnose symptoms. The study was conducted at the Biology Laboratory of the Federal Institute of Piauí (São João do Piauí campus) using isolates cultured on Potato Dextrose Agar (PDA) medium. Cultural and morphological characteristics were evaluated, including mycelial growth, colony color and texture, conidial production, and microscopic features of hyphae and spores. Mycelial growth was measured every two days using a digital caliper; data were subjected to analysis of variance (ANOVA) and Tukey's test (at a 5% probability level) using the SISVAR software. The isolates showed vigorous growth on the culture medium; while a significant difference was observed only at the second evaluation point, both isolates exhibited similar growth by the end of the assessment period. Colonies displayed abundant mycelium, a cottony texture, and conidial masses ranging from salmon to orange in color. Microscopic analysis revealed hyaline, septate, and branched hyphae, as well as conidia with morphology consistent with the genus Colletotrichum. Although species identification was not possible based solely on morphological characterization, the results expand knowledge regarding the fungus's characteristics in vitro and provide information to support future research on molecular identification, biology, and the development of management strategies for this important phytopathogen.