Larvicidal activity of Cyclamen(Myrsinaceae) extracts against the larvae of West Nile virus vector Culex pipiens L.(Diptera:Culicidae)

Objeclive:To evaluate the larvicidal activity of the tuber extracts isolated from two species of Cyclamen（Cyxltimen mimbile Hildebr.and Cyclamen alpinum Dammann ex.Sprcnger） against Culex pipiens L.（Diptera:Culicidae）.Methods:Twenty young（first-second） or older（third- fourth） instars of tile Culex pipiens were exposed to various concentrations（100 to I 000 ppm） of the extracts.Mortality was recorded after 12-,24-,48-.72- and 96-h of exposure.Results:We determined that the young larval stages were more susceptible to the extracts in comparison with the older larval stages.A comparison of LC;and LC;values has shown that Cyclamen mimbile was more active than Cyclamen alpinum.Conclusions:This study is the first to report on the larvicidal activity of the extracts of Cyclamen species against Culex pipiens.More studies are needed to isolate and identify the active components involved,their mode of action,and effects on other mosquito and pest species.