Effect of Cold Hexane Extract of Karanja (Pongamia Glabra Vent) Seed Kernel on the Development of Mosquito Larvae.

Cold Hexane extract of karanja, Pongamia glabra Vent (Fabaceae) seed kernel (HKSK) ranging at the concentrations of 4 ppm to 28 ppm was evaluated against the freshly emerged larvae of Aedes aegypti and Culex quinquefasciatus. Treatment of HKSK imparted the mortality that was correlated with the level of dosage. Before pupation,100% fatality occurred in Ae. aegypti at a concentration of 20 ppm whereas in Cx. quinquefasciatus the same degree of mortality occurred at the extract concentration of 12 ppm in the first instar larvae only. At low doses, the emerging adults of Cx. quinquefasciatus had deformed legs, wings and truncated abdomen but the adults of Ae. aegypti showed no deformities. The developmental period was prolonged significantly in a dose-dependent manner for both the species treated. In Cx. quinquefasciatus this effect was more pronounced because of increased intermoult period showing an IGR effect of the extract. The calculated growth index also decreased in dose-dependent manner significantly more in Cx. quinquefasciatus. Indeed, Ae. aegypti appeared more susceptible to HKSK than Cx. quinquefasciatus.

Use of mycelial suspension and metabolites of Paecilomyces lilacinus (Fungi: Hyphomycetes) in control of Aedes aegypti larvae.

Mycelial suspension of possible was assessed to examine its Paecilomyces lilanicus, a fungus, detrimental effects on fourth instar larvae of Aedes aegypti. The immature stages suffered 64-68% mortality with 0.5-1% mycelial suspension. There was 12-16% adult emergence which was statistically significant (P < 001). Czapeckdox and PYG media metabolites were used against the third instar larvae in various concentrations. The effects were evaluated on several parameters like mortality, mean survival time and time taken for adult emergence. The results indicate that the fungus does not producae any toxic metabolites.

Bioactivity of ethanol extract of Karanja (Pongamia glabra vent) seed coat against mosquitoes.

Laboratory evaluation revealed that the treatment of larvae of Aedes aegypti and Culex quinquefasciatus with ethanol extract of karanja seed coat (ALKSC) significantly increased the larval mortality and developmental period proportianately with increase in the extract concentrations. Aedes proved more sensitive to the effect of extract in terms of mortality than Culex. At a high concentration (8 ppm), 100% Aedes larvae died in the first instar within two days whereas, 16 pmm was required for achieving the same level of mortality in Culex. Culex was also found more sensitive than Aedes regarding IGR effect. In emerging Culex pupae several abnormalities were observed while Aedes pupae did not exhibit any abnormalities. However larvae which pupated successfully resulted in adults with several structural abnormalities in both the species.

Effects of aqueous extract of deoiled neem (Azadirachta Indica A. juss) seed kernel and karanja (Pongamia Glabra vent) seed kernel against Culex quinquefasciatus.

Aqueous extract obtained from deoiled neem and karanja seed kernels (ADNSD and ADKSK) were assessed for their toxic and growth regulating activities against Cx quinquefaciatus treated as first instar larvae. ADNSK at various concentrations was effective on the growth regulating mechanism, inducing prolonged larval stages. However, 100% larval mortality was observed, especially during the first and the second instars at all the tested concentrations. ADKSK caused 100% mortality in the fourth instar larvae and prepupae at the concentration of 100 ppm with no significant effect on the developmental period. The adults emerging from treated (50 ppm) larvae were smaller in size and malformed. We found ADNSK to be more effective than ADKSK.