Evaluation of repellent and larvicidal activity of hyptis suaveolens against filarial vector, Culex quinquefasciatus

Abstract

Mosquito vector control is facing a threat due to the emergence of resistance to synthetic insecticides. Safe and eco-friendly insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. Hyptis sauveolens (bush minth)  belonging to the  family, Lamiaceae is common and widely distributed in the south-eastern Nigeria. The repellent and larvicidal activity of the ethanol extract of this herbs against the filarial vector, Culex quinquefasciatus 3^rd instar larvae and adults respectively was investigated or 48 hours. The extract was screened chemically for phytochemicals. The extracts showed larvicidal and repellent activity with Lethal  Concentration ,LC_50, LC₉₀   and  Effective Dose, ED₅₀, ED₉₀  values 81.817mg/l, 166.704mg/g and 38.75mg/l , 258.925mg/l  respectively. Alkaloids, flavonoids, Tannins, Saponins and Steroids were the phytochemicals  present. Repellency and mortality were observed to  significantly and positively correlated with  the concentrations of the ethanol extracts  (p<0.05). The  present study revealed that an indigenous common weed, Hyptis suaveolens could be considered as potential natural larvicidal and repellent agent against mosqutoes.