LARVICIDAL ACTIVITY OF PERESKIA BLEO (KUNTH) DC. (CACTACEAE) FRUIT ENDOCARP CRUDE AND FRACTIONATED EXTRACTS AGAINST AEDES AEGYPTI (L.) (DIPTERA: CULICIDAE) Damrongpan Thongwat1,2, Lucksagoon Ganranoo3 and Ratchanaporn Chokchaisiri3

The use of insecticides can cause adverse effects in vector control, a plant bio-insecticide is an advantageous substitute. Currently, the promising mosquito larvicidal activity from plant extracts has been reported worldwide, including Thailand. In this study, the endocarp of Pereskia bleo (Kunth) DC. fruit was extracted with distilled water and ethanol. Crudes and fractionated groups of the extracts were evaluated for their larvicidal efficacy against the 3rd instar larvae of Aedes aegypti. At 48 hours of exposure, it was found that the activities of the extracts were higher than 24-hour’s. The ethanolic extracts showed stronger activities than the aqueous ones, indicating the lower LC50 values of both crude and fractionated group extracts. The most toxic activity was found in a fractionated group of the ethanolic extract, E-Gr3, with significantly lowest LC50 values of 707.94 and 223.12 ppm for 24and 48-hour detection times, respectively. The bioassay results indicated the larvicidal property against the Ae. aegypti mosquito of the P. bleo plant extracts. A safety for non-target organisms or an action on other mosquito vectors of this plant, should be further investigated.