The role of entomopathogenic nematodes in regulating the abundance of pest species: a generalised model.

Abstract

Entomopathogenic nematodes provide a potential control agent for invertebrate pests and may be capable of regulating the abundance of these pests in the long term. This paper examines the conditions when entomopathogenic nematodes may be capable of regulating invertebrate pests. Unlike most nematodes, entomopathogenic nematodes exhibit the characteristics of microparasites and we apply a basic microparasite model to the system. Two models are developed, Model 1 considers the situation for heterorhabditid nematodes and Model 2 for steinernematid nematodes. In both systems, regulation occurs in pest species at high density when there is a high contact rate between parasite and host and each host produces abundant infective stages that have a high life expectancy. Overall, heterorhabditid nematodes are more likely to be effective control agents than steinernematid nematodes since only one nematode is necessary for infection.