Occurrence of Sclerotinia Wilt on Vegetable Crops in Anambra State, South East Nigeria

Sclerotinia sclerotiorum causes wilt, crown rot, and basal stem rot across a broad range of vegetable host species and has been associated with crop failures in cool, moist environments worldwide. In Anambra State, the wet season creates conditions that may favour Sclerotinia disease establishment, yet little formal documentation of its occurrence on local vegetable crops exists. This study investigated the occurrence of Sclerotinia wilt on selected vegetable crops, including tomato, okra, and amaranth, across four local government areas of Anambra State. Field surveys were conducted during the 2023 rainy season, and symptomatic plants with cottony mycelial masses and hard black sclerotia were sampled for laboratory analysis. S. sclerotiorum was confirmed through morphological identification and pathogenicity trials on seedlings. Disease occurrence was confirmed in 63 percent of surveyed farms, with highest incidence in okra crops grown in close proximity to previously affected tomato plots. Vegetable farms situated in low-lying areas with extended periods of high canopy humidity showed significantly higher Sclerotinia infection rates. Farmers were unfamiliar with the sclerotial survival stage of the pathogen and therefore did not apply preventive soil management strategies. The study recommends deep ploughing to bury sclerotia, rotation with cereals, and the evaluation of biocontrol agents, particularly Trichoderma-based products, as components of integrated Sclerotinia management in South East Nigeria. Keywords: Sclerotinia sclerotiorum, wilt, vegetable crops, Anambra, disease occurrence.