Abstract:

Fourth and fifth instars larvae of fall webworm， Hyphantria cunea，were infected with different concentrations of Hyphantria cunea nucleopolyhedrovirus (HcNPV). Survivors were collected and reared in laboratory respectively. Mortality of the larvae，average weight of the single pupae，laying eggs for the female and hatch rate of the eggs were observed in parental generation and successive filial generations. The results showed that the virus not only led to death of larvae in parental and filial generation，but also impacted the average weight of the single pupa and laying eggs，especially to the parental and the first filial generation. The virus could weaken the host in filial generations，which could control populations of the host for a long time. Meanwhile，it was proved that HcNPV can spread and diffuse in the host population by many approaches.

Key words: sustainable effect, Hyphantria cunea nuclear polyhedrosis virus (HcNPV), diffusion approach