一、瓜类白毛病。瓜类白毛病是白粉病的俗称。南瓜、西瓜、黄瓜、冬瓜、甜瓜等都有感染,分布广,发生严重。病菌一旦侵染很快蔓延。在各种瓜类生长中后期发生尤重,如不及时防治,会引起瓜叶枯焦,果实早期生长缓慢,瓜藤早衰,影响瓜的品质和产量。瓜白毛病,侵染瓜叶、叶柄、茎蔓。初发生时叶片正面和背面出现小圆形白斑粉状霉点,随后扩大成白色 First, melon white hair disease. Melon white matter is commonly known as powdery mildew. Pumpkin, watermelon, cucumber, melon, melon, etc. are infected, widely distributed, serious. Once the infection of bacteria spread quickly. Occurred in a variety of melons in the late particularly serious, if not timely control, will cause melon leaves Kujiao, early fruit growth slow, melon vine premature aging, affecting melon quality and yield. Melon white, infected melon leaves, petioles, stems and vine. Occurred at the beginning of leaves on the front and back of a small white powdery mildew point, and then expanded to white