A SIMPLE AND EFFICIENT PROCEDURE FOR THE ORAL INOCULATION OF TRICHOPLUSIA-NI LARVAE WITH POLYHEDRIN-NEGATIVE RECOMBINANT BACULOVIRUS

Current procedures for inoculating lepidopteran larvae with polyhedrin -negative recombinant baculovirus, i.e. intracoelomic injection or coi nfection with wild type virus, are laborious and can compromise final yields of recombinant protein. Herein is described a simple and effici ent method for oral inoculation. Up to 100% infection was obtained whe n individual early fifth instar Trichoplusia ni larvae were fed a smal l piece of a formaldehyde-free insect diet to which 4.2 x 10(5) PFU of a polyhedrin-negative recombinant Autographa californica nuclear poly hedrosis virus (AcNPV) containing the gene for beta-galactosidase was applied. Infected larvae were identified by assaying hemolymph for bet a-galactosidase activity. The maximum levels of beta-galactosidase det ected in these hemolymph samples were identical to those obtained for larvae infected by intracoelomic injection. The dose of polyhedrin-neg ative recombinant virus recommended for intracoelomic injection of T. ni was efficacious for the oral route of inoculation.