A Survey of Puerto Rican Soils for Entomogenous Nematodes Which Attack Diaprepes abbreviatus (L.) (Coleoptera:Curculionidae)

Abstract

A survey was conducted to determine the presence of entomogenous nematodes which might parasitize Diaprepes abbreviatus (L.) larvae in Puerto Rican soils. One larva (2.3%) was parasitized with Heterorhabditis sp. Poinar when 4-month-old larvae were placed in the soil at eight different sites throughout the Island. Soil samples, taken from sugarcane fields and pasture lands in five geographical regions during July and September 1980, and January and April 1981, and inoculated with D. abbreviatus larvae did not reveal entomogenous nematodes. In the laboratory, when Neoaplectana carpocapsae Weiser was introduced into sterile soil from these regions, 40% of the exposed D. abbreviatus larvae became infected. We believe this is the first report of the entomogenous nematode, Heterorhabditis sp., occurring in Puerto Rico.