Survey of Choanephora Wet Rot on Okra (Abelmoschus esculentus) in Osun State, South West Nigeria

Okra (Abelmoschus esculentus) is a commercially and nutritionally significant vegetable in Osun State, commonly cultivated in both rural homesteads and peri-urban market gardens. Choanephora wet rot, caused by Choanephora cucurbitarum, is a fungal disease characterised by soft, water-soaked rot of flowers, pods, and growing tips, which can rapidly devastate okra crops under humid conditions. This survey investigated the incidence and severity of Choanephora wet rot in okra farms across three local government areas of Osun State during the 2023 rainy season. A total of 48 farms were surveyed at biweekly intervals, with disease rated based on the proportion of plants with infected flowers or pods. C. cucurbitarum was isolated from all symptomatic samples, confirmed through the distinctive sporangial and sporangiophore morphology characteristic of the species. Wet rot incidence peaked at 58 percent during August, coinciding with the period of heaviest rainfall and highest relative humidity. Farms with dense plant populations and inadequate sunlight penetration showed significantly higher incidence than widely spaced plots. Irrigation using overhead sprinklers was positively associated with wet rot incidence compared to drip-irrigated plots. Farmers were generally familiar with the disease but relied on repeated copper fungicide applications as the sole management strategy. The study recommends improved spacing guidelines, alternation to drip irrigation, and management of plant debris to reduce Choanephora inoculum in Osun State okra fields. Keywords: okra, Choanephora wet rot, Choanephora cucurbitarum, Osun State, disease incidence.