Insecticidal Activities of Chromolaena odorata and Vernonia amygdalina leaf extracts against Anopheles gambiae [Diptera: Culicidae

Omotayo Olabimi Isaac,David Ileke Kayode

doi:10.23937/ijtd-2017/1710018

Abstract

Female Anopheles mosquitoes are the vectors of human malaria. The use of chemical insecticides for vector control has hampered with environmental pollution and insect. This suggests the need for the development of more potent and environment-friendly insecticides for effective control of malaria.This research investigated the larvicidal, pupicidal and adulticidal activities of Chromolaena odorata and Vernonia amygdalina leaf extracts against, An. gambiae in the laboratory at ambient temperature of 28 ± 2 °C and 75 ± 5% relative humidity. Different concentrations of 20 mg/L, 40 mg/L, 80 mg/L, 120 mg/L and 160 mg/L were prepared and these aqueous solutions were used for the experiments. Larval, pupal and adult mortality of An. gambiae were tested after 24 hours of exposure. Results showed that there were significant differences (P < 0.05) in toxicity level of the two plant extracts on An. gambiae larvae, pupae and adults. Vernonia amygdalina extract was the most toxic to An. gambiae larvae at all tested concentrations of 20 mg/L, 40 mg/L, 80 mg/L, 120 mg/L and 160 mg/L causing 47.5%, 82.5%, 100%, 100% and 100% mortality after 24 hours of treatment, respectively.

Highlights

Several diseases are transmitted by arthropod vectors [1] of which mosquito is one of them
Mosquitoes are responsible for the transmission of diseases such as malaria, lymphatic filariasis, and dengue fever among others [2] most especially in the tropical regions of the world. Out of these diseases transmitted by mosquitoes, malaria is the most devastating in terms of the number of incidence, prevalence, morbidity and mortality [2]. It is transmitted by the mosquitoes of the genus Anopheles and it is caused by the protozoa of the Plasmodium genus [3]
The aim of this research study isto investigate the antimosquito activities of C. odorata and V. amygdalina leaf extracts on the larvae, pupae and adults of malaria vector, An. gambiae

Summary

Introduction

Several diseases are transmitted by arthropod vectors [1] of which mosquito is one of them. The major method that have been employed in the control of mosquitoes is the use of synthethic insecticides such as chlorodane, aldrin, Dieldrin, dichlorodiphenyl trichoroethane (DDT) among others [4] These chemical have been shown to have negative effect in the dynamics of the earth’s ecosystem resulting in resistance of mosquito species to the chemicals, environmental pollution and toxicity to human and other non-targeted organisms [10]. There have been clamor by various quarters to develop a safe means to combat the proliferation of insect vector species [11] This has led to the focus on developing insecticides from botanical sources that are safe to use in the environment due to the fact that they are degradable and less toxic to humans and non-targeted organisms [12,13]. The aim of this research study isto investigate the antimosquito activities of C. odorata and V. amygdalina leaf extracts on the larvae, pupae and adults of malaria vector, An. gambiae

Materials and Methods

Result

Discussion

Conclusion