西瓜叶枯病病残体上病菌的存活力及其传病作用

在土表、田边草丛和室内纸盒中的病残体上越冬的西瓜叶枯病菌（Ａｌｔｅｒｎａｒｉａｃｕｃ－ｕｍｅｒｉｎａＥｌ．ｅｔＥｖ．），次年均有传病作用；在稻田水中和稻田泥下５～１０ｃｍ处的病菌，３个月内失去传病力；旱地土下５～１０ｃｍ处的病菌，经３～６个月也相继失去传病力；旱地土表和田边草丛中的则需６～１５个月失去存活力。木霉可加速病残体上病菌的死亡

Studies on Leaf Blight of Watermelon Survival and Infectivity of the Dormant Pathogen in the Crop Residues

The pathogen of watermelon leaf blight (Alternaria cucumerina Ell. et Ev.)overwintering in the crop residues laying on ground or among weeds near watermelon field or on the kraft box in the room would have capacity causing the disease in the coming year. The residues with the pathogen that were put into water and soil in rice field as deep as 5～10cm would lose their infection ability in 3 months, and those into dried soil 5～10cm deep gradually in 3～6 months,but those laying on ground or among weeds near wat...