Non-chemical methods of controlling eggplant fruit and shoot borer, Leucinodes orbonalis (Guenee) (Lepidoptera: Pyralidae)

Due to excessive use of synthetic insecticides and the very high demand for organically grown eggplant, there is an urgent need to evaluate the effectiveness of non-chemical control methods (release of Euborellia annulata Lucas. Trichogramma spp.,spraying of langkauas + oregano crude extracts, planting of lemon grass as repellent and sanitation) against eggplant fruit and shoot borer (EFSB), Leucinodes orbanalis Guenee, the most destructive insect pest of eggplant. The experiment was conducted at the Central Experiment Station UPLB [University of the Philippines Los Baños], from February to December 2015. The effectiveness of the non-chemical methods was compared with that of spraying methomyl, the conventional method of controlling EFSB. The field releases of Trichogramma in combination with the release of earwig, were separately conducted in organic farm in San Pablo City (SPC), Laguna [Philippines]. Based on two trials at UPLB, release of earwigs, and spraying of langkauas + oregano crude water extracts were consistently as effective as methomyl in reducing EFSB fruit damage. The highest yield was obtained from plants in plots where earwigs were released and those sprayed with methomyl. However, the highest net income was obtained from plants released with earwig, E. annulata followed by spraying of langkauas + oregano crude extracts and sanitation. Lower net profit was obtained with the conventional insecticide application since the insecticide is quite expensive while the market price of produce is higher for organically grown crops. The field releases of Trichogramma and earwigs at SPC resulted in crop yield comparable with that of spraying of crude plant extracts. Results suggests that each of the component control methods (release of earwigs; Trichogramma; spraying of langkauas + oregano extracts and sanitation) could contribute in reducing EFSB damage, thereby increasing the yield of eggplant. The effectiveness of field releases of earwig, spraying of langkauas + oregano extracts and sanitation) could contribute in reducing EFSB damage, thereby increasing the yield eggplant. The effectiveness of field releases of earwig, spraying of langkauas + oregano crude extracts, and sanitation in combination with the release of Trichogramma egg parasitoid, is currently being verified in an organic farm in San Pablo City.