Effect of Neem (Azadirachta indica) Leaves Extracts on Bactrocera carambolae Drew and Hancock (Diptera: Tephritidae) Oviposition on Mango (Mangifera indica)

Neem tree (Azadirachta indica) is broadly recognized as a plant that has some biological activities against some insect pests. This research aimed to investigate the activity of water, methanol and n-hexane neem leaves extracts on oviposition of B. carambolae. The results revealed that all the extracts tested have the potential as oviposition deterrents against B. carambolae, but n-hexane extract was the most oviposition deterrent among them. It was indicated by its consistency on the deterring oviposition for all concentrations tested. n-Hexane extract at concentration of 1,000; 2,500 and 5,000 ppm deterred B. carambolae oviposition with oviposition activity index (OAI) of -0.76, -0.87 and -0.51, respectively. Based on olfactometry test, the mechanism of neem leaves extracts in protecting fruits from eggs deposition by B. carambolae was most likely by deterrence mechanism rather than repellency. The main compound found in the n-hexane extracts was nonacosane. This results contributes in obtaining a safe tool for controlling B. carambolae, by spraying the fruits whether with the n-hexane extract of neem leaves or with nonacosan.