打瓜白粉病是常见且易发生的一种病害,主要危害瓜果类作物,从苗期到收获期均可发生,该病分布广,危害较重,一旦感染,病菌蔓延很快,如不及时防治,会引起瓜叶枯焦,果实生长缓慢,瓜藤早衰。打瓜白粉病主要危害叶片,发病初期在叶面上出现灰白色霉点,后逐渐向四周扩散,形成近圆形斑块,条件适宜时霉斑扩张迅速,病斑相连成一片,使整个叶片覆盖一层白粉状物,严重时瓜面也可出现白粉状物。通风不良、透光性差、荫蔽繁茂,当田间湿 Fight melon powdery mildew is a common and prone to a disease, the main damage to fruits and vegetables, from seedling to harvest can occur, the disease is widely distributed, more serious, once infected, the bacteria spread rapidly, if not Timely prevention and treatment, will cause melon leaves Kujiao, fruit growth is slow, melon vine premature aging. Fight melon powdery mildew main hazards leaves, early onset of gray mildew on the foliage, and then gradually spread to four weeks to form nearly circular plaque, mildew expansion under appropriate conditions when the rapid expansion of spots into one, so that the entire leaf cover A layer of white powder, melon can also occur in severe white powder. Poor ventilation, poor light transmission, lush shade, when the field wet