Análise filogenética de isolados de Fusarium spp. agentes etiológicos da podridão da coroa em banana no Brasil

Abstract

Banana (Musa spp.) belongs to the order Zingiberales, family Musaceae, and genus Musa. Originating from Southeast Asia and the Western Pacific, it has been introduced and widely cultivated in various regions of the world. Currently, it is the most produced fruit globally and the second most consumed, with Brazil ranking as the sixth largest producer. In Brazil, production reached approximately 6.9 million tons in 2024, with a strong emphasis on domestic consumption.Despite its economic importance, banana production faces challenges due to postharvest diseases, which affect fruit quality and lead to economic losses. Crown rot has been identified as one of the main diseases, caused by a complex of fungi, particularly Colletotrichum spp., Lasiodiplodia spp., Verticillium spp., and especially Fusarium spp. The disease typically manifests after fruit ripening, compromising its marketability. Therefore, the objective of this study was to perform molecular, morphological, and pathogenic characterization of Fusarium spp. isolates obtained from different banana cultivars in Brazil. A total of 40 Fusarium spp. isolates were collected from asymptomatic banana hands in 10 municipalities across the states of Ceará, Goiás, and Rio Grande do Norte, Brazil. These isolates were georeferenced and obtained from the cultivars Prata, Nanica, and Grand Naine. The isolates were subjected to morphological analysis, molecular characterization (using TEF1 and RPB2 genes), and pathogenicity tests. Phylogenetic analysis revealed significant species diversity within the following complexes: Fusarium fujikuroi Species Complex (FFSC), Fusarium incarnatum-equiseti Species Complex (FIESC), and Fusarium oxysporum Species Complex (FOSC). Within the FFSC, Fusarium musae was the most prevalent species; within the FIESC, Fusarium sulawesiense and Fusarium pernambucanum were prominent. In the FOSC, Fusarium triseptatum and Fusarium fabacearum were identified. Pathogenicity tests demonstrated that all isolates were capable of causing disease symptoms, with F. triseptatum (FOSC) being the most aggressive. These results highlight the complexity of banana crown rot, with multiple Fusarium species contributing to the disease.