Elimam Abdalla M, Elmalik Khitma H, Ali Faysal S
Department of Biology, Faculty of Education, Al zaiem Al azhari University, Sudan.
Trop Biomed. 2009 Aug;26(2):130-9.
Malaria and filariases are prevalent in Sudan and their control depends largely on preventive measures against mosquito vectors. The present work aimed to investigate the larvicidal, adults emergence inhibition and oviposition deterrent effects of aqueous extracts from leaves of Ricinus communis L. against the mosquitoes, Anopheles arabiensis and Culex quinquefasciatus as a biological control means. The larval mortality was observed after 24 hours. The LC50 values calculated were 403.65, 445.66 and 498.88 ppm against 2nd, 3rd and 4th instar larvae of An. arabiensis and 1091.44, 1364.58 and 1445.44 ppm against 2nd, 3rd and 4th larval instars of Cx. quinquefasciatus. 50% of adult emergence inhibition (EI50) were 374.97 and 1180.32 ppm against 3rd instar larvae of An. arabiensis and Cx. quinquefasciatus. The extract showed oviposition deterrent effect against both species. Results reveal that the crude extract of R. communis possesses remarkable larvicidal, adult emergence inhibition and oviposition deterrent properties against both the tested species and can be used as biological control means.
疟疾和丝虫病在苏丹流行,其防治很大程度上依赖于针对蚊媒的预防措施。本研究旨在调查蓖麻叶水提取物对阿拉伯按蚊和致倦库蚊的杀幼虫、抑制成虫羽化和驱避产卵作用,作为一种生物防治手段。24小时后观察幼虫死亡率。计算得出的针对阿拉伯按蚊2龄、3龄和4龄幼虫的LC50值分别为403.65、445.66和498.88 ppm,针对致倦库蚊2龄、3龄和4龄幼虫的LC50值分别为1091.44、1364.58和1445.44 ppm。针对阿拉伯按蚊和致倦库蚊3龄幼虫的50%成虫羽化抑制率(EI50)分别为374.97和1180.32 ppm。该提取物对这两种蚊虫均表现出驱避产卵作用。结果表明,蓖麻粗提取物对两种受试蚊虫均具有显著的杀幼虫、抑制成虫羽化和驱避产卵特性,可作为生物防治手段。