A sustainable IPM system for oil palm in Papua New Guinea

Oil palm is an important cash crop in Papua New Guinea (PNG), with about 80,000 hectares in cultivation, grown both on large-scale plantations and by smallholders. The principal pests of oil palm in PNG are a group of insect species from the Tettigoniidae family (Orthoptera), known collectively as sexava. Three species of sexava are pests of oil palm in PNG, Segestes decoratus, S. defoliaria and S. novaeguineae. These insects cause damage by feeding on oil palm fronds and defoliation levels call be very severe where high populations occur. Severe defoliation causes reductions in photosynthesis resulting in yield loss from lower fruit production. During the last five years an integrated system has been developed for the management of sexava. The integrated pest management (IPM) system described here has the following components:- (1) a knowledge of the biology and ecology of the pest, (2) economic thresholds, (3) monitoring system for the pest, (4) precise targeting of chemical control agents, (5) biological control and (6) cultural and physical control. The IPM system is sustainable and environmentally acceptable to the industry. Future research involving the development of strepsipteran parasites for biological control is likely to improve this system still further.