Mosquito repellent potential of Pithecellobium dulce leaf and seed against malaria vector Anopheles stephensi(Diptera:Culicidae)

Objective:To determine the repellent properties of hexane,benzene,ethyl acetate,chloroform and methanol extract of Pithecellobium dulce(P.dulce)leaf and seed against Anopheles stephensi(An.stephensi).Methods:Repellent activity assay was carried out in a net cage(45 cm×30 cm×25 cm)containing 100 blood starved female mosquitoes of An.stephensi.This assay was carried out in the laboratory conditions according to the WHO 2009 protocol.Plant crude extracts of P.dulce were applied at 1.0,2.5,and 5.0 mg/cm^(2) separately in the exposed fore arm of study subjects.Ethanol was used as the sole control.Results:In this study,the applied plant crude extracts were observed to protect against mosquito bites.There were no allergic reactions experienced by the study subjects.The repellent activity of the extract was dependent on the concentration of the extract.Among the tested solvents,the leaf and seed methanol extract showed the maximum efficacy.The highest concentration of 5.0 mg/cm^(2) leaf and seed methanol extract of P.dulce provided over 180 min and 150 min protection,respectively.Conclusions:Crude extracts of P.dulce exhibit the potential for controlling malaria vector mosquito An.stephensi.