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油菜蚤跳甲是陕甘塬区白菜型油菜上的重要害虫。幼虫春季先蛀食叶肉后转蛀根茎,新羽化成虫对将熟角果为害也烈。成虫羽化后有明显的趋上、趋绿、群集和伪死4种特性。调查表明,春季每株油菜内平均有幼虫20头以上时才对产量有影响。可根据下式进行测报防治: 20(经济域值幼虫量)≤N(10月中旬每亩成虫基数)×100(繁殖系数)/P(每亩株数)10月下旬用2.5％辛硫磷或1605两种粉剂每亩2kg,效果极佳。
Brassica campestris is an important pest on Brassica campestris in Shaanxi and Gansu provinces. The larvae first eaten in the spring after the moths turn the roots, the new emergence of adults will harm ripe cocoon also. After the emergence of adults there is obvious tendency to trend green, cluster and pseudo-death four kinds of characteristics. Surveys show that when there are more than 20 larvae per rape per spring in spring, the yield is affected. It can be controlled according to the following formula: 20 (economic larval amount) ≤ N (mid-October per acre adult base number) × 100 (multiplication coefficient) / P (per acre) In late October, 2.5% phoxim 1605 two kinds of powder per acre 2kg, the effect is very good.