Behavioural study in relation to oviposition of wild Culex quinquefasciatus in laboratory condition

Abstract

Mosquito borne diseases are majorcontributors to the communicable disease burden in the South-East Asia region. In the present investigation, both immature and mature stages of various mosquito species were collected from different localities of Ganjam district, Odisha during 2016. Mosquitoes were identified based on the examination of the taxonomic keys and Culex quinquefasciatus mosquitoes were abundantly available in almost all selected study sites.In order to find out oviposition preference, gravid female Cx. quinquefasciatus were allowed to oviposit in ovitraps with different concentrations of NaCl, in different colouredovitraps, in water from different sources, in larva holding water and in different sized ovitraps. Results of laboratory oviposition bioassays showed that the number of egg rafts laid by gravid Cx. quinquefasciatus gradually decreased with increase in NaCl concentration. When gravid mosquitoes were allowed for oviposition in different colour edovitrap, black ovitrap was found to be the most preferred colour by this mosquito species. Water samples collected from different sources were used in the ovitraps to understand the oviposition preference of this mosquito species. Water collected from paddy field was found to be the most preferred water among all other water sample surveyed. Further, it was noticed that Cx. quinquefasciatus laid maximum number of egg rafts in ovitraps containing larva holding water than distilled water. In relation to the container size, female adult Culex mosquito deposited apparently more egg rafts in the largest ovitrap taken.