Occurrence of Damping-Off of Okra in Florida, Caused by Pythium aphanidermatum

During summer 2025, yellowing, stunted, and dying okra plants were observed in a 50-acre field in Homestead, FL, U.S.A. Three isolates of microorganisms associated with symptomatic plants were obtained and identified as Pythium aphanidermatum based on the morphological characteristics and DNA sequencing. Phylogenetic analysis based on ITS, CoxII, and β-tubulin sequences confirmed the identification. The pathogenicity of the Pythium isolates was confirmed on okra, revealing a high mortality rate up to 60 and 2.5% for pre- and postemergence damping off, respectively. This is the first report of P. aphanidermatum causing severe damping-off of okra in Florida and may pose a serious threat to okra production in Florida if not managed properly.