Abstract

Culex mosquitoes play a vital role in transmitting pathogens which continue to have a harmful impact on human beings. Indeed, Innovative vector control strategy like use of plant extracts as alternative sources of insecticidal and larvicidal agents against vector-borne diseases has become unavoidable. In this context, the purpose of the present search was to explore the larvicidal properties of Jatropha curcas L. leaf and seed extracts against Culex pipiens L. The larvicidal activity was evaluated in eight different provenances recently introduced in Tunisia (Tanzania (ARU), Mozambique (MOZ), Surinam (SUR) and Brazil represented by five provenances: Paraná (PAR), Norte de Minas (NMB), Mato Grosso (MGB), Regiao Sureste (RSB) and Vale do Fequitinhonha (VFB). The assessment of larval activity showed after 24 h of exposure, 100% mortality for aqueous seed extract and between 60 and 100% for aqueous leaf extract according to provenances. Highest mortality is observed at 1 mg/ml against C. pipiens L with LC₅₀ values of 0.49 and 0.5% for aqueous seed extract and leaf extract, respectively. Commonly, the mortality increase with the increase in concentration of each extract. However, the inhibitory effect of seeds extract on C. pipiens was more pronounced than that of leaves. These results suggest that the aqueous seed and leaf extracts of J. curcas have the potential to be used as an ideal eco-friendly compound for the control of hurtful mosquito larvae.

Key words: Aqueous extract, Culex pipiens L., Jatropha curcas L., larvicidal activity.