Growth of a clonal cell line of Helicoverpa zea (Lepidoptera : Noctuidae) in suspension culture and replication of its homologous baculovirus HzSNPV

A clonal cell line (BCIRL-HZ-AM1-11) of Helicoverpa zea was grown in statio nary and suspension cultures in ExCell 401 (TM) medium containing 10% fetal bovine serum at 28 degreesC. The cell population doubling time was 22 h in stationary culture as compared with 27 h in suspension culture. A lag time of approximately 24 h was observed during the first 24 h of the suspension culture following initiation but no lag time was observed in the stationar y culture. Maximum viral titers were achieved in stationary and suspension cultures at 120 h (1.80 X 10(6) TCID50/ml) and 168 h (1.48 X 10(7) TCID50/m l), respectively, following inoculation with the Helicoverpa zea baculoviru s (HzSNPV/Br-CL2). Infected cells harvested at 168 h from the 50 ml suspens ion culture produced a total number of occlusion bodies of 3 X 10(9).