Bio-efficacy of crude leaf extracts of Acalypha fruticosa Forssk. against some agriculturally important insect pests

ObjectiveTo investigate the antifeedant and larvicidal activities of Acalypha fruticosa Forssk. (Euphorbiaceae) (A. fruticosa) leaf extracts.MethodsEfficacy of various organic solvent extracts of dichloromethane, acetone, dimethyl sulfoxide and aqueous extracts of the leaves of A. fruticosa were evaluated for their feeding inhibition and larvicidal activities against third instar larvae of Leucinodes orbonalis (L. orbonalis), Helicoverpa armigera (H. armigera), Spodoptera litura (S. litura) and Earias vittella (E. vittella). Antifeedant and larvicidal activities were performed by leaf and fruit discs no-choice method at 0.625%, 1.25%, 2.5% and 5% concentrations.ResultsThe results revealed that 5% concentration of dichloromethane extract had significant antifeedant activity on L. orbonalis (77.1%), H. armigera (66.2%), S. litura (74.8%) and E. vittella (67.2%) followed by acetone, dimethyl sulfoxide and aqueous extracts. The result on larvicidal activity also showed that the 5% concentration of dichloromethane extract exhibited significantly higher larval mortality for L. orbonalis (62.12%), H. armigera (62.14%), S. litura (55.11%) and E. vittella (77.15%) when compared to acetone, dimethyl sulfoxide and aqueous extracts.ConclusionsFrom this study, it is concluded that the dichloromethane extracts of leaves of A. fruticosa could serve as a potential natural pesticide for further exploration of active compounds.