Efficacy of Entomopathogenic Nematodes Versus Diaprepes Abbreviatus (Coleoptera: Curculionidae) Larvae in a High Clay-Content Oxisol Soil: Greenhouse Trials with Potted Litchi Chinensis (Report‪)‬

ABSTRACT In a previous study, laboratory trials indicated that 9 strains and species of entomopathogenic nematodes (EPNs) were pathogenic against larvae of Diaprepes abbreviatus in an Oxisol from Puerto Rico. In this study we tested the efficacy of 5 species/strains of EPN in an Oxisol under greenhouse conditions. The nematodes were applied at 100 infective juveniles per [cm.sup.2] to 19-L pots containing a high clay-content Oxisol (69% clay) and 3 seedlings of Litchi chinensis. All treatments significantly reduced the mean proportion of D. abbreviatus larvae surviving (ranging from 0 to 36%) compared to survival in untreated controls (ranging from 80 to 86%). This suggests that EPNs might be suitable to play a role in integrated pest management strategies against D. abbreviatus in tropical soils with high clay content.