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近年来,甜菜象虫发生面积日益增大,为害程度日趋严重,一般减产11—25%,严重者达50%以上,甚至绝收。如1981年,据山西省轻工厅调查,应县播种甜菜2.4万亩,因象虫全面发生,毁种1.5万亩;朔县贾庄乡贾庄大队播种500亩,毁种400亩。1983年,据大同糖厂原料科调查,大同糖厂原料区播种13万亩,甜菜象虫普遍发生,致使3
In recent years, asbestos beetle area increases, the degree of damage is more serious, the general cut 11-25%, in serious cases up to 50% or even absolute. For example, in 1981, according to a survey conducted by Shanxi Light Industry Bureau, 24,000 mu of sugar beet should be planted in Yingxian County. Due to the occurrence of elephantidae and pests, 1.5 million mu of species were destroyed. Jiazhuang Brigade of Jiazhuang Township in Shuo County sowed 500 mu and destroyed 400 mu of species. In 1983, Datong sugar factory raw materials, according to investigation, Datong sugar raw materials planted 13 million mu of sugar beets, asbestos insects common occurrence, resulting in 3