In order to study the mechanism of action of tea saponin on Pieris raPae,antifeedingeffect of tea saponin on P. rapae 5-instar larva was examined,and contact poison and stomach poi-son actions of tea saponin on P. rapae 4-instar larva were also examined.

• 为探讨茶皂素对菜青虫的作用方式，测定了茶皂素对菜青虫Pierisrapae（Lin-naeus）5龄幼虫的拒食作用，以及对4龄幼虫的触杀和胃毒作用。