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菜茎象(虫甲)(Ceutorrhynchus asper Roel)属鞘翅目象(虫甲)科。幼虫危害十字花科植物的茎秆,是一种蛀茎害虫,主要危害冬油菜,也危害种用萝卜和甘兰,群众称“油菜象鼻虫”。该虫在我区宁县、正宁、庆阳、镇原县不论山、川、塬、水、旱地都有发生为害,一般为害率30—40％,严重的高达90％以上。每株有幼虫10-20头,最少2头,最多86头。此虫为害后,轻者造成籽粒秕瘦,结实率降低,减产3—4成,重者成片死亡,减产一半以上。如在宁县长庆桥川水地调查,平均危害率95.3％;正宁县山地调查,平均为害率64.3％;塬
Ceratoidea (Pest) (Ceilotrhynchus asper Roel) is a Coleoptera (Anchovy) families. The larvae endanger the stems of cruciferous plants. They are a type of stem-bore pests that mainly endanger the winter rapeseed. They also endanger the use of radish and cabbage, and the masses call it “rape weevil.” The insect in our district Ningxian, Zhengning, Qingyang, Zhenyuan counties regardless of mountains, rivers, plateau, water, dry land have occurred harm, the general damage rate of 30-40%, a serious up to 90%. Each plant larvae 10-20, at least 2, up to 86. After the pest damage, the light caused by the thin seedlings, reduced seed set, cut 3-4, severe cases of death, cut more than half. For example, in Changqing County, Ningxia, the investigation of the Hashigawa River, the average hazard rate was 95.3%. In the mountainous area of Zhengning County, the average damage rate was 64.3%.