How to Treat Konjac Diseases? A Detailed Guide to Prevention and Control Methods
As early as 3000 years ago, our country had already begun cultivating and using konjac, and there are abundant konjac resources in the hilly areas of the southern provinces, the Qinling-Daba Mountains region, the Sichuan Basin, the Yunnan-Guizhou Plateau, southern Yunnan, and Taiwan, China. So how do you treat konjac diseases?
1. Soft rot
Soft rot is a bacterial disease that mainly affects the leaves, petioles, and underground corms of konjac. It can occur during the konjac growing stage and even during the storage period after harvest. The symptoms of soft rot are: the affected area slowly turns yellow, then wilts, and finally becomes a gray or brown rotting mass with a foul odor.
Prevention and control: Oxalic acid solution, agricultural streptomycin, or thiophanate-methyl solution can be used for prevention and control.
2. Southern blight
Southern blight is a fungal disease that mainly affects the stems, petioles, and underground tubers of konjac. After southern blight develops, irregular brown water-soaked spots appear on the affected area, and as the condition worsens, they further soften, ultimately causing the plant to lodging. When there is excessive moisture in the field, white mycelium may also appear, eventually infecting the underground corms and causing them to rot.
Prevention and control: For southern blight, chlorothalonil or carbendazim can be used for prevention and control.
3. Root rot
Root rot is a fungal disease that mainly affects the roots of konjac. In the early stage of the disease, the part of the aboveground stem close to the underground corm slowly turns yellow, then the entire plant turns yellow and wilts, and finally the underground corm is affected; in severe cases, the underground corm directly rots.
Prevention and control: Carbendazim and chlorothalonil can be used for prevention and control.
The konjac varieties with relatively high utilization value include six species: Amorphophallus konjac, Amorphophallus albus, Amorphophallus tianyangensis, Amorphophallus ximengensis, Amorphophallus youleensis, and Amorphophallus menghaiensis. China and Japan cultivate konjac on a large scale.