First Report of Damping-off Caused by Pythium Aphanidermatum in Seedlings of Wax Gourd

In February 2023 in Japan, seedlings of wax gourd [ Benincasa hispida (Thunb.) Cogn.] in seedling boxes developed water-soaked rot on hypocotyls typical of damping off and eventually died. A Pythium sp. was isolated from the hypocotyls and was identified as Pythium aphanidermatum based on morphological characteristics and DNA sequence data. The same symptoms developed after seedlings were inoculated with the isolated fungus, and the same fungus was reisolated from the seedlings. This is the first report of damping off in wax gourd seedlings caused by P . aphanidermatum in seedling boxes in Japan.