大葱干尖已成为大葱优质高产的一大障碍,常造成品质下降、产量降低,直接影响菜农的经济效益。了解造成大葱干尖的原因,采取针对性防治对策十分重要。1大葱灰霉病和霜霉病造成的干尖1.1症状灰霉病干尖:初在叶上生白色斑点,多由叶尖向下发展,并可向下延伸2～3cm,干枯。湿度大时在 Onion dry tip has become a green onion high yield and quality of a major obstacle, often resulting in decreased quality, lower yields, a direct impact on farmers economic benefits. To understand the causes of Onion dry tip, take targeted control measures is very important. 1 Onion gray mold and downy mildew caused by dry tip 1.1 Symptoms Botrytis dry tip: the beginning of white spots on the leaves, mostly from the tip down development, and can be extended down 2 ~ 3cm, dry. When humidity is high