Effects of nuclear polyhedrosis virus formulations on Lymantria dispar larval peritrophic membrane
The peritrophic membrane is a continuous tube that encases the food in the midgut and hindgut of Lepidopteran larvae. It presumably protects midgut cells from abrasion by food particles, and perhaps acts as a barrier to infection. The gypsy moth, Lymantria dispar, is susceptible to a nuclear polyhedrosis virus (LdMNPV), which is transmitted per os. Once ingested, viral occlusion bodies (OB) dissolve in the alkaline midgut, liberating virions that ultimately invade susceptible cells. Recent studies have shown that selected stilbenedisulfonic acid derivatives administered in combination with LdMNPV significantly enhance viral potency, but the precise mode of action is unknown. We tested the effect of the stilbene derivative, Blankophor BBH (Burlington Chem. Co., Burlington, NC), on potency of LdMNPV in gypsy moth larvae, and determined the effects of ingested BBH/LdMNPV combinations on the surface structure of the peritrophic membrane.Newly molted second instar larvae were fed high wheat germ diet overlaid with either water, LdMNPV (102-106 OBs/ml), BBH (0.5%), or LdMNPV + BBH.