Effect of spices upon the activity of the gypsy moth (Lepidoptera: Lymantriidae) nucleopolyhedrovirus

The ability of host plants to influence the incidence and severity of diseases in insects has been known for more than 20 yrs and may play a critical role in the efficacy of insect pathogens, including viruses. In this study, we investigated the effects of 35 spices from 15 plant families, on the activity of the gypsy moth nucleo-polyhedrovirus (LdMNPV) infecting the gypsy moth, Lymantria dispar (L.). The activity of LdMNPV was not affected in 29 different virus/spice combinations, whereas six virus/spice combinations (NPV/cayenne, NPV/curry, NPV/dill, NPV/nutmeg, NPV/paprika and NPV/tarragon) enhanced activity of the virus against gypsy moth larvae. These findings indicate that several of these spices may be useful as viral enhancers and should be further investigated to obtain more efficacious formulations for the control of agriculturally important insect pests.