Exploiting oviposition pheromone-an innovative way to control mosquitoes

Abstract

Mosquitoes have tremendous impact on both human and animal health as vectors of serious diseases. The mosquito oviposition pheromone (MOP, caproic acid), can be employed in an ‘attract and kill’ strategy as an alternative approach in control of mosquitoes. MOP (1 ppm) was impregnated in both vapour patch and Whatmann no.1 filter paper as well as encapsulated in calcium alginate beads for sustained release. The impregnated vapour patch as well as filter paper were air dried and placed in plastic cups containing 250 ml of water and left undisturbed indoors for a period of 24 hours. Similarly, plain vapour patch and plain filter paper without pheromone impregnation were kept as control. The number of mosquito egg rafts in cups containing pheromone lure as well as control was monitored and counted. The egg rafts were removed and destroyed by drying in the sun. An ovi-trap was designed and field trials were carried out to assess its efficacy. In-vitro trials for a period of one month revealed 89.28%, 3.57%, 7.14% of Culex spp. egg rafts deposited by adult mosquitoes in containers with pheromone impregnated vapour patches, filter paper and calcium alginate encapsulated with 1 ppm concentration of MOP, respectively whereas, no Culex egg raft was observed in the controls. These ovi-traps can be effectively used for the control of mosquitoes.