Outbreaks of bagworms (Lepidoptera: Psychidae) and nettle caterpillars (Lepidoptera: Limacodidae) in oil palm occasionally affects some estates in Malaysia. Control involves mainly the use of systemic chemicals such as monocrotophos and methamidophos and the spraying of selective narrow spectrum insecticide such as triclorfon. Chemical insecticides pose several potential hazards such residual problem, insect pest resistance to chemicals and increased frequency of pest outbreaks. In the 1991 national biological control conference, integration of selective chemicals with biological control was recommended as a strategy towards non-polluting agriculture in Malaysia. Use of baculovirus (BV) as a biological control agent supports this recommendation. The objective of this study is to report the progress made in collection, isolation and amplification BV for the control of some oil palm insect pests.

Collections of 62,000 larvae of Metisa plana, Wlk (Lepidoptera: PSychidae) and 1000 other pests were made in 1992-1995 from 20 estates in Selangor, Johor, Negeri Sembilan, Pahang, Sabah and Perak. The larvae were dissected, treated and examined for BV infection, particularly the subgroup A and B. The results indicated that nucleopolyhedrosis virus (NPV) was detected in M. plana, but the degree of infection was tertiary, meaning that it did not successfully infect the host. Granulosis viruses (GV) were detected more frequently than the NPV. Detection of BV was enhanced in stressed and newly dead larvae.

To date, Mahasena corbetti NPV (McNPV), Darna trima GV (DtGV), Spodoptera litura NPV (S1NPV), Mamestra brassicae NPV (MbNPV), Agrotis segetum NPV (AsNPV), A.segetum GV (AsGV), Autographa californica NPV (AcNPV) (L1, 210,449) and Panolis flammae NPV (PfNPV) have been purified. Mass production of BV for field experiment has been by in vivo amplification of these viruses in an alternative host, S. litura was carried out. The amplified viruses and cross-infectivity studies against oil palm insect pests.