一.洋葱生育期病虫种类及危害 1.根蛆 主要危害洋葱根部,使其地下部分腐烂,地上部分萎蔫,枯死,洋葱受害达9.76％。 2.葱蓟马 危害洋葱叶片,形成许多灰白色斑点,严重时,导致叶片扭曲,畸形,且能传播病毒病,洋葱受害达12.78％。 3.紫斑病 叶片受害,形成灰白色梭形病班,病斑上有黑色霉 I. Growth and development of onion pest species and hazards 1. Root maggot main harm onion roots, the underground part of decay, the above part of the wilting, dead, onion damage up to 9.76%. 2. Thistle species endanger onion leaves, the formation of many gray spots, severe, leading to leaf distortion, deformity, and can spread viral diseases, onion damage up to 12.78%. 3. purple spot leaf damage, the formation of fusiform shuttle class, black mold on the spot