Mosquito survey and larvicidal activity of actinobacterial isolates against Culex larvae (Diptera: Culicidae)

The present study aims to survey and identify the mosquito vector distribution throughout the Bharathidasan University Campus, Tiruchirappalli district, Tamil Nadu, India. Mosquito larvae were collected during October 2012–December 2012 from different breeding habitats. The survey revealed the presence of Aedes sp., Anopheles sp. and Culex sp. mosquito larvae. Among them Culex is dominant, in particularly Culex pipiens followed by Culex quinquifasciatus. Totally 41 actinobacterial isolates were isolated from soil and screened for the production of larvicidal metabolites against the 3rd instar Culex larvae. The obtained data exhibited that the isolated metabolites have lethal effects. Five isolates have shown a most significant mortality rate of the Culex mosquito larvae. In the biolarvicidal assay 1000 ppm concentration of the isolate KA13-3 showed 100% mortality and KA25-A showed 90% mortality after 24 h of incubation.