In vivo isolation of baculovirus genotypes.

Restriction endonuclease profiles of a wild-type granulosis virus from Artogeia rapae (ArGV3) and a nuclear polyhedrosis virus from Lymantria dispar (LdMNPV) indicated that the preparations were genotypically heterogeneous. Eight constituent genotypes were isolated from ArGV3 by low mortality dose infections of late instar A. rapae and analysis of progeny viral DNA recovered from individual cadavers. Three distinct genotypes were isolated from LdMNPV by the same approach, using L. dispar larvae. These results show that larval mortality can occur as a consequence of productive infection by a single virus particle. Comparative physical mapping of the eight ArGV3 genotypes suggested that their diversity may be partly attributable to recombination during natural coinfection.