Repellent and oviposition-deterrent efficacies of Cuscuta chinensis on filarial vector Culex quinquefasciatus

Abstract

In the laboratory, crude and chloroform: methanol extracts of Cuscuta chinensis seeds were evaluated for repellence and oviposition deterrence activities against adults of Culex quinquefasciatus at various concentrations. Hundred percent protection was attained from a 99% concentration of chloroform: methanol extract for 120 minutes whereas from the crude extract for the first 90 minutes with a gradual decrease. Crude and chloroform: methanol extracts of seeds were found to be highly effective in preventing oviposition of adult mosquitoes. Furthermore, neither extract has any negative side effects such as allergy or other observable reactions on human skin during or after the exposure period. Oviposition activity index (OAI) was negative at all concentrations for tested plant extracts which indicated an inhibition of Cx. quinquefasciatus oviposition. So, against Cx. quinquefasciatus mosquito species, crude and chloroform: methanol seed extracts of C. chinensis may be utilized as a repellent and oviposition deterrent.