Adulticidal Effect of Crude Ethanol Extract of <i>Phytolacca dodecandra</i> on <i>Anopheles gambiae</i>

Abstract

Knockdown and not adulticidal effect of extracts of Phytolacca dodecandra (Endod) has been demonstrated against Anopheles gambiae adults. In this study we demonstrate adulticidal effect of ethanol extracts of mature green fruits and leaves of Endod on Anopheles gambiae adults in the laboratory. Material & Methods: Different concentrations (80, 40, 20, 10, 10, 5 and 2.5 mg) of Ethanol extracts of leaf and mature green fruits of Endod, Neem and deltamethrin were used to impregnate standard Whatman No. 1 filter papers and wall surfaces. Wall surfaces were modeled from plywood measuring 26 x 26 cm 2 . The surfaces were then smeared with a mixture of mud and cow dung, cement or used as it were (plain). Three to five day old laboratory and field sourced female An. gambiae were then exposed for five minutes, withdrawn put in clean paper cups and left to be observed for mortality after 24 hours. Results: Mortalities of exposed female An. gambiae were higher for extracts of Endod sourced from the highlands than that from the lowlands for laboratory reared (60%) and (40%) and field sourced (30%) and (28%) respectively. Mortalities were higher on modeled surfaces (61%) than on Whatman No. 1 papers (30%). Toxicity level of extracts of Endod were below the WHO threshold of >80% mortality irrespective of part or source. Deltamethrin met the threshold on all surfaces while Neem on cement surfaces only. Conclusion: Ethanol extracts of mature green fruits and leaves of Endod are a potential adulticide against An. gambiae adults.