加拿大蓟天敌─欧洲方喙象的寄主专一性测定

Biology and host range tests of Cleonus piger,a natural enemy of Crisium arvense

在温度为25-28℃的养虫室内选择具有代表性的菊科植物及豆科、禾本科牧草共10科30种植物对欧洲方喙象进行寄主专一性测定试验,结果表明其食性专一,只取食加拿大蓟,个别成虫或幼虫在饥饿状态下仅少量取食菊科其他植物,但随后即拒绝取食。非选择性试验(饥饿试验)表明欧洲方喙象耐饥饿能力强,不同龄期平均达28d。欧洲方喙象最适宜的生长温度是25℃,高于30℃或低于10℃,生长发育则受到抑制。

The bioassay of Cleonus piger Scopovi was carried out in the laboratory, in which temperature was set at 25-28 ℃. Totally ten families and thirty species including Compositae, Legumioosae and Gramineae were chosen to test the host specificity of C. piger. The results showed that C. piger mainly fed on Crisiurn arvense （L.） Scop. Only a few adults （or larvae） fed on a few other Compositae plants slowly when they were very hungry. The non- choice test results indicated that the capability of C. piger against hunger averaged as long as 28d for different instars was strong than others. The optimal growth temperature for C. piger was 25 ℃. If the temperature was over 30 ℃ or under 10 ℃, its growth and development would be checked.