After infection with Trichoplusia ni nuclear polyhedrosis viruses, the esterases in the hemolymph of the fifth instar larvae of the Argyrogramma agnata were examined by the polyacrylamide gel electrophoresis (PAGE) and thin - layer scanning. The results showed that TnNPV can inhibite the metabolism of the esterases at the early stages and the effects of heterologous NPV were different from those of homlogous NPV.
