Environmental Impacts of Entomopathogenic Nematodes Used for Biological Control in Soil

Abstract

Biological control is a powerful tactic that has been used to obtain many significant, well documented economic and public health benefits against pests in agroecosystems and against disease vectors (Caltagirone 1981, DeBach 1974, Pimentel et al. 1984). The use of biological control has generally been considered environmentally safe and risk-free (Batra 1982, DeBach 1974, Hokkanen and Pimentel 1989, Hoy 1992), especially in comparison to the widespread use of synthetic insecticides (Pedigo and Higley 1992, Pimentel et al. 1992). However, data to support the assumption of absence of environmental impacts are not regularly collected (Howarth 1991), and it cannot be assumed that the lack of published evidence of negative environmental impacts is evidence of their absence. Indications of the growing concern about this complex issue include the recent debate in the literature over the use of introduced biological control agents to manage rangeland grasshoppers (Carruthers and Onsager 1993, Lockwood 1993a, b).