Insect-associated Nematodes with Emphasizing on Entomopathogenic Species

Most nematodes are free-living. They live in oceans, fresh waters and soil and feed on bacteria, fungi and other nematodes. Some are predators and some are parasites of plants and animals. Some of the latter group are insect-associated. There are different types of relations between insects and nematodes. Beneficial nematodes that cause disease in insects are referred to as “entomopathogenic” and have the ability to kill the insects. Entomopathogenic nematodes from the genera Stein¬ernema and Heterorhabditis have proven to be the most effective as biological control organisms. Only the infective juvenile stage of entomopathogenic nematodes will survive in the soil, find and penetrate insect pests. In this paper, different types of association between nematode and insect with emphazing on entomopathogenic nematode species have been reviewed.