date:Sep 23, 2021
A contagious disease is spreading among Japan's sweet potatoes. It's called foot rot disease, and since November 2018 it has been confirmed in Japan's southwestern prefectures of Okinawa, Kagoshima and Miyazaki. It then emerged in the eastern prefectures of Ibaraki and Chiba at the start of 2021. As of early September, cases have been confirmed in 20 prefectures, including Tokyo.
The disease is caused by a filamentous fungus. When the disease develops, plant leaves go red or yellow, and the ste