北京枝瘿象虫研究初报

A PRELIMINARY STUDY ON THE COCCOTORUS BEIJINGENSIS LIN ET LI

本文报导了北京枝瘿象虫(Coccotorus beijingensis Lin et Li)的生物学特性与药剂防治研究结果。在北京地区一年发生一代,成虫在虫瘿内越冬。翌年3月上旬,越冬成虫出蛰、交尾。中旬产卵。4月上旬,卵孵化。幼龄幼虫为害小叶朴树(Celtis bungeana BL.)的新梢,形成虫瘿。幼虫期150天左右。三龄幼虫有停育越夏的特性。8月中旬,幼虫化蛹。9月上旬羽化。10月上旬,成虫在虫瘿前端咬一圆形羽化孔越冬。成虫期240天左右。成虫出蛰期用40％氧化乐果1000倍+24％万灵500倍;或50％甲胺磷1000倍+90％敌百虫1000倍等混合药剂,连续喷药两次,间隔7天,累计防治效果达100％。

The Coccotorus beijingensis Lin et Li was a new species reported by Lin Kaijin and Li Guixiu in March 1990 and Genus of Coccotorus is a new record from China. This paper presents brief accounts on biology and control measures of shis insect. The insect only has a hoste [Celtis bungeana BL.], so it is called pests of single habit. This insect only has one generation a year in Beijing Region and over-winter as adult at insect gall. The adult stage is about 240 days and it comes out of the insect gall in early March of the following year and both sexs are on mating. The female lays eggs into the buds or on the young stems top in the middle part of March. Its eggs hatch into Larva in early April and they have the habit of eating in young stems to make young stems into insect gall. The Larva stage is about 150 days. The study also showed. For the control experiment sprayiny with one of the 24％ Lannatel 500 times add 40％ omethoat 1000 times mixture; or 50％ methamidophos 1000 times add 24％ lannatel 500 times mixture; or 90％ trichlorfon 1000 times add 40％ omethoat 1000 times mixtures, if one of these insecticides is sprayed once in early young Larva stage, the control effect can reach 100％, but if one of these insecticides is sprayed twice, when the adult comes out of the insect gall, the cumu lative control effect can also reach 100％.