Evaluation of Mosquito Larvicidal Activity of Ethanolic Extract of Grewia flavescens Juss. Whole Plant (Family: Tiliaceae) Against Culex quinquefasciatus

Abstract

To evaluate the mosquito larvicidal activity on the ethanolic extract of Grewia flavescens juss (EEGF). Whole plant against Culex quinquefasciatus larvae. The larval mortality of 4th instar larvae of Culex quinquefasciatus after 24h and 48h of treatment which were tested separately in control and five test concentrations of 125 ppm, 250 ppm, 500 ppm,750 ppm, 1000 ppm concentration. The plant extract was screened to identify phytochemical bioactive compounds like alkaloids, flavonoids, saponins, tannins and glycosides. Different concentration of crude ethanolic extract of Grewia flavescensjuss. whole plant effectively showed larvicidal activity on Culex quinquefasciatus larvae. Based on the probit analysis values for 24h and 48h ethanolic extract of Grewia flavescens shows pronounced larvicidal activity. The LC50 and LC90 values of EEGF against mosquito 4th instar larvae of Culex quinquefasciatus was found 223.87 ppm and 724.43 ppm at 24hrs and for 48hrs the LC50 and LC90 values was found to be 181.97ppm and 374.76 ppm respectively. The preliminary phytochemical was performed in search of plants secondary metabolites which might be responsible for the larvicidal activity. The bioactive phytochemical classes which were identified and confirmed as alkaloids, flavonoids, saponins, tannins and glycosides. The ethanolic extract of this plant showed potent larvicidal activity and can be considered for further investigation. This experimental study was a pioneer attempt to establish Grewia flavescens juss. as a valuable resource of effective target specific natural mosquito larvicide.
 Keywords: Culex quinquefasciatus, larvicidal activity, ethanolic ext., phytochemical.