Control of mosquito breeding through Gambusia affinis in rice fields.

Abstract

Studies on mosquito breeding and its control through Gambusia affinis in nursery and paddy fields after transplantation of seedlings were carried out during June to October 1991 in about 10 ha rice field area. Six anopheline species, viz. An. culicifacies, An. annularis, An. subpictus, An. nigerrimus, An. barbirostris and An. aconitus, and four culicine species, viz. Cx. tritaeniorhynchus, Cx. bitaeniorhynchus, Cx. quinquefasciatus, and Aedes sp. could be identified. These were found breeding in rice fields with fluctuations in their percentage composition, exhibiting species succession in different months. G. affinis survived well in submerged rice fields and provided 87.8% mosquito larval control. In rice fields which exhibited intermittent drying up leading to formation of pools, puddles etc., moderate larval control was achieved. However, in nursery rice fields, this method was not applicable. Mosquito larval control through larvivorous fish in rice fields can be achieved but the method has limitations.