Loading ...Author: Mangesh Chorge
Although synthetic insecticides are proved to be effective in pest control its frequent use causes major problems such as health hazards either by inhalation or ingestion of pesticide or its residue along with the food crop. Due to the public concern over the toxicity & environmental impact of conventional synthetic insecticides a novel kind of mosquito control is necessary. Genetically modified mosquitoes & exploration and utilization of naturally occurring products for combating harmful mosquitoes are the two possible ways to attain this goal. It turns out that analysis of the embryonic development of wild type mosquitoes is important in order to accomplish exogenous DNA injections, phenotypic analysis of mutants and even to define the expression pattern of new genes. However when culicidae species are concerned, morphological information on their developmental biology is limited. Therefore we decided to analyze Aedes aegypti embryonic development.
Further in order to take important step in exploration and utilization of naturally occurring products for combating harmful mosquitoes, we evaluated leaves extract of Annona squamosa for its inhibitory effect on the embryonic development of aedes aegypti mosquito, a most common vector of dengue virus in tropical countries. Dried, powdered leaves of Annona squamosa were macerated in methanol for 24hrs. filtrate is evaporated to dryness. Concentrated extract was tested for its inhibitory effect on egg hatching of Aedes aegypti and compared with water as control and temephos(50%EC) as standard synthetic insecticide. In another experiment, eggs were allowed to exposure of calcium hypochlorite and acetic acid for 30min. to render the egg chorion transparent, without affecting embryo morphological integrity. This enabled observation of embryo development under low power of binocular light microscope.
Embryos at typical major developmental stages were clicked through microscope camera. This work aims at filling a gap on mosquito embryogenisis knowledge, necessary as a toll in further studies directed towards the control of mosquitoes. The extract from the leaves of Annona Squamosa is a good inhibitor of mosquito breeding as it is environmentally safe and non toxic to humans as compared to temephos (50%EC).There is need for studies that will provide the basis for developing more effective prevention strategies, including bioenvironmental factors responsible for mosquito breeding and new mosquito control measures. We hope this study would enable such an approach.
About the author:
Mangesh is a R&D executive. He has a M.Sc. (By research)In Applied Biology from Haffkine Institute For Training, Research & Testing, Parel, Mumbai and a passion to improve the Quality of community health with his nine years experience in Diagnostic Field. He is also pursuing MBA