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粘虫为远距离迁飞害虫,忻定盆地历年为二、三代粘虫的发生区。七十年代以来,由于生态条件的变化,已成为二代常发区,大发生频率高,受害面积大。三代偶有发生。一、发生规律二代粘虫从江淮一代随气流迁飞而来,一般5月上、中旬为始见期,5月下旬蛾量逐步上升,伴有高峰出现。6月上、中旬蛾量猛增,多次出现大的蛾峰,开始见卵。盛卵期在6月上旬末及中旬初,卵期8天左右。6月中旬末为孵化盛期,7月初幼虫大量进入4龄,因而6月下旬为防治适期。据调查,卵块产在麦叶上,初龄幼虫在麦田
Armyworms migrate pests for long distances, Xin Ding basin over the years for the second and third generation of armyworm occurrence area. Since the seventies, due to the change of ecological conditions, it has become the second generation of common areas, with high frequency of occurrence and large area of victimization. Three generations happen occasionally. First, the occurrence of the second generation of armyworms from Jianghuai generation migrated with the flow of air, usually in May on the middle of the initial period, moths in late May gradually increased, accompanied by the peak. In June, the amount of moths soared sharply in mid-to-middle period, and large moths appeared many times and began to see eggs. Sheng oviposit late in early June and mid-early, oviposit 8 days. The end of mid-June is the incubation period, early July a large number of larvae into the 4th age, so in late June for the prevention and treatment of the right period. According to the survey, eggs produced in wheat leaves, the first instar larvae in the wheat field