Bio-Pesticides: New Tool for the Control of Aedes (Stegomyia) albopictus (Culicidae: Diptera) in Pakistan

BACKGROUND Application of plant extracts as mosquito control strategy was practiced from centuries. These are easily available, non-toxic, biodegradable and exhibit broad-spectrum target specific activities against larval stages of mosquitoes. METHODS Different potential parts of locally grown plants, seeds of nutmeg (Myristica fragrans), peel of musambi (Citrus sinensis), leaves of babuna (Matricaria chamomilla), mint (Mentha spicata) and ginger rhizome (Zingiber officinale) selected and evaluated for their larvicidal properties against Aedes (Stegomyis) albopictus. Oils were extracted through steam distillation process and extracts were evaluated as per WHO 2005 guidelines for testing of insecticides against larvae of mosquitoes. RESULTS Among the five plant extracts, C. sinensis had the lowest LC50 (400.81ppm) while M. fragrans had the highest LC50 value (710.30ppm) respectively after 24h of exposure. In terms of % age mortality, a series of concentrations (300-800ppm) gave high % mortality in case of C. sinensis while M. fragrans gave low % age mortality. CONCLUSION All the five plant species have larvicidal effects to certain extant and C. sinensis had great potential. Further small-scale field trials with the extracts of the most promising one (C. sinensis) shall be conducted to determine operational feasibility.