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1.常见病害核桃白粉病危害叶片幼芽和新梢,造成早期落叶,甚至苗木死亡,7月-8月发病,发病初期叶片退绿或造成黄斑,严重时叶片扭曲皱缩,幼芽萌发而不能展叶,在叶片的正面或反面出现圆片状白粉层,后期在白粉中产生褐色或黑色粒点。防治方法:连续清除病叶、病枝并烧掉,加强管理,增
1 common diseases walnut powdery mildew hazards of young leaves and shoots, resulting in early deciduous, and even death of seedlings, July-August onset, the early onset of leaves green or cause macular macular degeneration, severe leaf distortion, bud germination and Can not show leaf, appear in the front or back of the leaf disciform white powder layer, later in the white powder to produce brown or black particles. Prevention and treatment methods: continuous removal of diseased leaves, diseased branches and burn, strengthen management, increase