Observations on the pupal productivity of Culex tritaeniorhynchus in rice fields of West Bengal, India: implications for vector management (Diptera: Culicidae)

Abstract

The mosquito Culex tritaeniorhychus is an established vector of Japanese encephalitis in India and many Asian countries. Entomological monitoring enables estimation of the abundance of the vector mosquitoes and therefore aids in vector management and disease control. In compliance with this proposition, an assessment of the pupal productivity of the mosquito C. tritaeniorhynchus was made from selected rice fields of West Bengal, India. The results are expected to provide the present status of mosquitoes in an endemic region of Japanese encephalitis. In course of sampling of the rice fields, the mosquito C. tritaeniorhyhchus was found in abundance with other mosquitoes like Culex bitaeniorhynchus, Anopheles subpictus, Anopheles vagus, Anopheles barbirostris. Application of multivariate analysis indicated that the plant height, water depth and temperature could explain the variations in the pupal productivity of C. tritaeniorhynchus in rice fields. The correspondence of the immature abundance of C. tritaeniorhynchus with plant height suggests persistence of the population throughout the paddy rice cultivation period. Using the plant height as an indicator, the abundance of the mosquito C. tritarniorhynchus can be predicted enabling application of appropriate strategies for population intervention and thus the possibility of the disease.