Identification and Pathogenicity of Verticillium dahliae Causing Wilt Disease in Eggplant Under Field Conditions

Abstract

Wilt disease caused by Verticillium dahliae is a serious soil-borne fungal disease affecting eggplant cultivation and leading to significant reductions in plant vigor, yield, and fruit quality. Accurate identification and pathogenicity assessment of the causal pathogen are essential for effective disease diagnosis and management. The present study investigated the identification and pathogenicity of V. dahliae associated with wilt disease in eggplant under field conditions. Diseased eggplant plants exhibiting characteristic symptoms including chlorosis, vascular discoloration, wilting, and stunted growth were collected from infected fields. The pathogen was isolated using standard microbiological techniques and identified based on colony morphology, microsclerotia formation, and microscopic examination of fungal structures. Molecular confirmation was performed through polymerase chain reaction (PCR)-based analysis using species-specific primers to verify pathogen identity. Pathogenicity tests were conducted by artificial inoculation of healthy eggplant seedlings under controlled conditions to fulfill Koch’s postulates. Inoculated plants developed typical wilt symptoms, confirming the virulence of the isolated pathogen. Significant variation in disease severity and aggressiveness was observed among different isolates collected from various locations. Environmental conditions such as soil temperature and moisture were found to influence disease development and pathogen establishment in the field. The integration of morphological, molecular, and pathogenicity analyses provided comprehensive insights into the biology and variability of V. dahliae populations affecting eggplant crops. The findings contribute valuable information for disease monitoring and support the development of integrated disease management strategies aimed at reducing wilt incidence and improving sustainable eggplant production.