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酒花霜霉病是一种毁灭性病害,在我国酒花栽培区普遍流行,并且常年发生,轻者产量品质下降,重者严重减产以至绝收。此病在河西地区一般5月份开始发病,幼苗被初次侵染,6月上中旬开始次侵染,到7—8月份,在湿度适宜的条件下,来势猛、蔓延快,反复循环侵染,迅速流行,造成毁灭性灾害。发病主要条件是低温、高湿,一般在架上密度大,灌水次数多,灌量大,积水多或连续阴雨的情况下极易发病。 1.症状:叶、花、球果、枝蔓、根茎及芽都可发病。叶片发病初沿叶脉出现边缘不明显的细小水渍状黄绿色病斑,后扩展为黄褐色多角形病斑,且互相融合成大病斑变成褐色,叶背面产生软毛状灰白色霉层,后
Hop downy mildew is a devastating disease in our horticulture generally popular and perennial occurs, the light of the decline in the quality of production, serious serious production cuts as well as absolute. The disease in Hexi area generally onset in May, the seedlings were infested in the beginning of June infection in the middle of the beginning, from July to August, under the conditions of appropriate humidity, Meng Meng, spread fast, repeated cycle of infection, Rapid popularity, causing devastating disasters. The main condition is the incidence of low temperature, high humidity, the shelf density in general, the number of irrigation, irrigation, water or more continuous rainy conditions easily. 1. Symptoms: leaves, flowers, cones, branches, roots and buds can be disease. At the beginning of leaves, there appeared little yellowish-green lesion with little edge on the edge of veins, which then expanded into yellowish-brown polygonal lesion and merged with each other into large lesion into brown, Rear