Relative toxicity of neem fruit, bitter gourd, and castor seed extracts against the larvae of filaria vector, Culex quinquefasciatus (Say).

In search of a natural larvicide, petroleum ether, carbon tetrachloride, and methanol extracts of Azadirachta indica fruits and seed extracts of bitter gourd (Momordica charantia) and castor (Ricinus communis) were tested for larvicidal activity against Culex quinquefasciatus. Among the extracts tested, the methanol extract of Az. indica was observed the most potent with LC(50) at 74.04 and 58.52 ppm and LC(-90) at 201.83 and 171.70 ppm as compared to methanol extract of M. charantia with LC(50) at 101.18 and 93.58 ppm and LC(90) at 322.81 and 302.62 ppm carbon tetrachloride extract of R. communis with LC(50) at 144.11 and 92.44 ppm and LC(90) at 432.42 and 352.89 ppm after 24 and 48 h, respectively. The methanol extract of Az. indica exhibited potential results and can be exploited as a preferred natural larvicide for the control of filarial vector, Cx. quinquefasciatus.