Quaid I Azam University Islamabad Islamabad, Islamabad, Pakistan
Abstract: The mosquito-borne flaviviruses are causing major diseases in humans every year across the globe, resulting in a significant burden of morbidity and mortality. Dengue is the most common flaviviruses mosquito-borne disease predominantly transmitted by the Aedes (Stegomyia) aegypti mosquito. It is one of the fastest-growing global infectious diseases, with 100–400 million new infections a year. Phytochemicals are advantageous in vector control strategies due to their target-specificity, eco-friendly, and no development of resistance, higher acceptability and suitability for rural areas. The current study was carried out to assess the role of larvicidal activities of seven Pakistan native medicinal plants viz. Albizia lebbeck, C. fistula, D. sisso, F. palmate, M. azedarach, Z. mauritiana and Z. namularia against the 1st to 4th instar dengue vector Ae. aegypti larvae reared in entomology laboratory, Quaid I Azam University Islamabad, Pakistan. The experimented plants extracts (80 ppm to 400 ppm (multiple of 80)) were taken in 300 ml plastic containers, added 200 ml distilled water and 25 larvae, fed with dog biscuits. Each experiment was setup in triplicates along with control. Among the experimented plants M. azedarach found to be the most affective. The M. azedarach showed 96% mortality of 1st instar larvae at 400 ppm after 72 hrs. showing LC50 (114.179) and LC90 (433.425) with Chi-Square value of 33.3039, DF:4 and P = 0.000. The morphology of dead larvae observed under microscopic showed adverse effects of plant extracts indicating shrinkage and damaged comb scale and siphon. The plants were comparatively analyzed for their biochemical constituents using UV, FTIR, GCMS. The results obtained from this study showed a potential toxicity of M. azedarach extracts in the control of Ae. aegypti mosquito larvae. This is a new eco-friendly approach which can be used for vector control. Therefore, this study provides first report on the larvicidal activities of seven plant extracts against larvae of Ae. aegypti mosquito from Pakistan. Key words: Larvicidal bioassay, Aedes aegypti, mortality, plant extracts, concentration, probit analysis
