水葫芦象甲的生物学及其寄主专一性

The Biology and Host Range of Water Hyacinth Weevil,Neochetina eichhorniae,an Insect Agent for the Control of the Weed

在室温 2 5～ 2 8℃的养虫室内 ,水葫芦象甲雌成虫寿命最长可达 1 6 1d ,最大卵量为 1 0 91粒。产卵期为 2 0～ 1 59d。卵主要产在叶柄内。幼虫孵化后在叶片内和叶柄中取食 ,并向植株基部钻蛀。幼虫期 30～ 4 0d。老熟幼虫在活的水葫芦植株根部化蛹 ,蛹期 2 5～ 30d。在温州自然条件下 ,象甲年发生 2代 ,并有明显的世代重叠现象。以成虫和幼虫越冬。利用 2 3科 4 6种植物进行的寄主专一性测定发现 ,该象甲只为害水葫芦 。

The water hyacinth weevil, Neochetina eichhorniae was originally introduced from Argentina into China in 1995. The adult preferred to attack younger leaves and fed on the epidermal layer and the underlying cells and left a lot of 'feeding scars' on the leaves. The longevity of the adult was between 29 and 161 d with an average of 104 d. The female laid 84-1091 eggs during this pariod. The larvae tunneled inside the petiole and crown of the host plants, and completed their growth in 30-40 d, then pupated underwater attaching to living roots of the floating plants. Pupae required 25-30 d for development. Two overlapping generations occurred in a year in Wenzhou. Host range tests with 46 plant species from 23 families showed the weevil only attacked and completed its life cycle on water hyacinth in choice and no choice tests, indicating that the weevil could safely be used to control water hyacinth in China.