Toxicity and bioefficacy of selected plantrnextracts against the mosquito vector Culex pipiens L. (Diptera: Culicidae)

Abstract

In this study, thernlarvicidal activity and bioefficacy of two different extracts (acetone andrnhexane) of Artemisia herbalba, Lavandula multifida, Peganum harmalarnand Ruta chalepensis against the 3rd instar larvae of Culexrnpipiens was performed under laboratory evaluation. The toxicity values ofrnacetone extracts based on Lc50 values may be arranged in arndescending order as follows: R. chalepensis > P. harmala >rnA. herbalba> L. multifida. On the contrary, hexane extracts mayrnbe arranged as follows: L. multifida > A. herbalba >rnP. harmala > R. chalepensis. The data also revealedrnsignificant decrease in growth index in treated individuals ranged (2.00 -rn8.90) when compared to control (11.25). The sublethal concentrations of thernacetone extracts induced sterility in the progeny of C. pipiens mosquitoesrnranged 61(R. chalepensis) -73% (A. herbalba) whereas,rnhexane extracts induced sterility ranged 55 (A. herbalba) -64% (R.rnchalpensis). There are no negative effects on the hatchability of eggs.