Infection of Spodoptera frugiperda and Choristoneura fumiferana cell lines with the baculovirus Choristoneura fumiferana nuclear polyhedrosis virus

Abstract

The growth properties of cell lines derived from Spodoptera frugiperda (alfalfa looper) and Choristoneura fumiferana (spruce budworm) were investigated. The data demonstrated that the spruce bud worm cell line grew more slowly than the alfalfa looper cell line, and this reduced growth rate appeared to affect the rate of baculovirus replication in infected cells. Trypsinizing the spruce budworm cells or varying the multiplicity of infection did not greatly influence the rate of viral replication. Autographa californica nuclear polyhedrosis virus was able to replicate its DNA and synthesize late and very late proteins in both cell lines but did not produce infectious extracellular virus in the spruce budworm cell line. The replication cycle of C. fumiferana nuclear polyhedrosis virus did not produce late proteins or infectious extracellular virus in the alfalfa looper cells. The results indicate that S. frugiperda cells are nonpermissive for the C. fumiferana nuclear polyhedrosis virus but C. fumiferana cells are semipermissive for the A. californica nuclear polyhedrosis virus, resulting in an abortive infection.Key words: baculovirus, host specificity, AcMNPV, CfMNPV, spruce budworm.