1985年北疆沿天山(精河——昌吉)一带,大白菜遭受普遍性的大面积病虫害,冬白菜大量减产,造成了上述地区冬菜的紧张局势.大部分地区产量比历年减少百分之七十以上,乌苏至沙湾的白菜全都死光了.普遍病症是:白菜植株矮小,叶面卷曲,皱缩,大部分不能包心,蚜虫密集为害;有的虽包了心,但受病毒病和霜霉病之害,叶脉上有褐色坏死条斑以至腐烂,这与白菜生长期的气候条件有密切的关系. 大白菜的生长以温和湿润而阳光充足的气候最为适宜,也就是说温度、日照、降 In 1985, along the Tianshan Mountains (Jinghe-Changji) in the northern part of the country, cabbage suffered from widespread pests and diseases and a large number of winter cabbage production was reduced, resulting in the tense situation of winter vegetables in most of the areas. The output in most areas dropped by 7% over the previous year More than ten cabbage, wusu to Shawan cabbage all died out.The general condition is: cabbage plants short, curly folds, folds, most can not be wrapped, aphid-intensive; some although wrapped in the heart, but the virus Disease and downy mildew damage, necrosis on the veins of brown streaks and decay, which is closely related to the climatic conditions of cabbage growth period.Chinese cabbage growth with mild and humid sunshine climate is most appropriate, that is, the temperature , Sunshine, drop