Pathogenicity test of major fungal pathogens in vanilla (Vanilla planifolia Andrews)

Vanilla (Vanilla planifolia Andrews) is an economically important spice crop affected by several fungal diseases that significantly reduce yield and quality. The present investigation was undertaken to isolate, identify, and prove the pathogenicity of major fungal pathogens associated with vanilla under Konkan conditions. Diseased samples of leaves, stems, roots, and pods were collected and subjected to tissue isolation on Potato Dextrose Agar (PDA). The isolated fungi were purified, mass multiplied, and tested for pathogenicity on healthy vanilla plants and pods following Koch’s postulates. Five major fungal pathogens, namely Colletotrichum gloeosporioides Penz., Fusarium oxysporum F. sp. vanillae Schlecht, Rhizoctonia bataticola (Taub.) Butler, Sclerotium rolfsii Sacc and Aspergillus niger van Tieghem, were isolated and confirmed. Pathogenicity tests revealed characteristic symptoms such as stem rot, leaf spot, basal rot, wilting, and pod rot. Reisolation of pathogens confirmed their causal role. The study highlights the importance of these fungal pathogens in vanilla cultivation and provides a basis for developing effective disease management strategies.