Insect-borne diseases remain to this day a major source of illness and death worldwide. The resistance to chemical insecticides among mosquito species has been considered as a setback in vector control. Mosquito control programs, botanical origin may have the potential to eliminate eggs and larvae. So, the larvicidal and ovicidal activities of crude benzene, hexane, ethyl acetate, chloroform and methanol extracts of were assayed for their toxicity against three important vector mosquitoes, viz.,, , and The larval mortality was observed after 24 h of exposure. All extracts showed moderate larvicidal effects; however, the highest larval mortality was found in the methanol extract of against the larvae of, , and with the LC values were 87.13, 93.24 and 111.98 ppm, respectively. Mean percent hatchability of the ovicidal activity was observed 48 h post treatment. The percent hatchability was inversely proportional to the concentration of extract and directly proportional to the eggs. All the five solvent extracts showed moderate ovicidal activity; however, the maximum egg mortality (zero hatchability) was observed in the methanol extract of at 200 and 250 ppm against, and showed 100% mortality at 300 ppm. No mortality was recorded in the control. The finding of the present investigation revealed that the leaf extract of possesses remarkable larvicidal and ovicidal activity against medically important vector mosquitoes and make this plant product promising as an alternative to synthetic insecticide in mosquito control programs.

The objective of the present study was to investigate the mosquito ovicidal, oviposition deterrent and larvicidal efficacy of hexane, benzene, chloroform, ethyl acetate and methanol extracts of, Lobophora variegata against malarial vector Anopheles stephensi. Among the five extract tested, the methanol extract was notable, which attained the 100 percent mortality at the concentration of 200.0 ppm and the hatchability rate ranged from 71.3 to 36.3 percent. In laboratory oviposition deterrent test, the extract of L. variegata greatly reduced the number of eggs deposited by gravid An. stephensi. The maximum and significant diminished fecundity in An. stephensi was observed with methanol extract which caused 76.15­–97.69% effective deterrence. Larvicidal response of An. stephensi was more susceptible in methanol extract. The LC50 ­value of methanol extract was 61.63 ppm and the Chi-square value were significant at p<0.05 level. It is concluded, that the extract of L. variegata could be used in control of malarial vector An. stephensi.

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