In vitro host range of five baculoviruses in lepidopteran cell lines.

The in vitro host range of five nuclear polyhedrosis viruses (NPV) was assessed in five lepidopteran cell lines from three genera. Multiple-enveloped baculoviruses of Autographa californica (ACMNPV), Trichoplusia ni (TNMNPV), and Galleria mellonella (GMMNPV) replicated in cells of T. ni, Spodoptera frugiperda, and Heliothis virescens to a titer of approximately 10(7) TCID50/ml. The multiple-enveloped baculovirus of S. frugiperda (SFMNPV) replicated only in S. frugiperda cells. The single-enveloped baculovirus of H. zea (HZSNPV) replicated in cells of H. zea and H. virescens but not in cells of H. armigera, T. ni, or S. frugiperda. Low levels of replication of ACMNPV, TNMNPV, and SFMNPV in cultures of H.zea, H. virescens, and T. ni, respectively, could not be detected by using a sensitive tritiated thymidine technique. However, two characteristically labelled peaks at densities of 1.145 and 1.245 g/ml were obtained in H. virescens cells inoculated with ACMNPV.60 min postinoculation ACMNPV particles were observed both entering and inside S. frugiperda cells but were not observed in H. zea or H. armigera cells. None of the five baculoviruses replicated in H. armigera cells.