甘薯台龟甲对五爪金龙的取食力测定

The feeding ability of Cassida circumdata(Coleoptera:Chrysomilidae)on Ipomoea cairica(Dicotyledoneae:Convolvulaceae)

试验结果表明,甘薯台龟甲幼虫对五爪金龙具有较强的取食力,取食力随着虫口密度的增加而增强。幼虫期的取食力(y)和投放1龄幼虫密度(x)的线性关系式为y=19.32+11.36x。每个叶片投放1龄幼虫2头,8d后取食力可达100%。甘薯台龟甲成虫对五爪金龙的取食力更为显著,每叶放虫1头,6d后取食量达100%,且取食力随着虫口密度的上升而提高。放虫后6d的取食力和成虫密度的对数关系式为y=51.09+120.67logx。成虫的投放密度达到1头/叶,6d后叶片就能100%被取食。

The test showed that the larvae of Ipomoea cairica could effectively feed on the alien weed Cassida circumdata and the feeding ability strengthened with the density increasing of the larvae.The relation between the feeding ability and the density of the first instar larvae could be described as y=19.32＋11.36x.The feeding ability could be reached 100% under feeding after 8 days with 2 of the first instar larvae to each leaf.The feeding of adult on the plant was similar to that of the larva,but more effective,the relation between the feeding ability after 6 days and the density of adult was y=51.09＋120.67logx,the whole leaves were fed with 1 adult to each leaf after 6 days.