Population fluctuations of fruit flies, Bactrocera spp., infesting cucumber monitored by attractant-insecticide bait traps

Population of fruit flies, Bactrocera spp., was monitored with the help of attractant-insecticide traps installed in cucumber field. Two types of traps, viz., suspension traps and wooden block traps were used. The catch consisted of males of mixed populations of Bactrocera tau (Walker), B. cucurbitae (Coquillett) and B. scutellaris (Bezzi), the latter dominating over the other two species. The mean catch was higher (23. 7 adults/ trap/ week) (ranging from 7.8-43.4 adults/ trap) in wooden block traps than suspension traps (16.6 adults/ trap/ week) (ranging from 4.6-28.4 adults/ trap). The maximum catch (43.4 adults/ trap) was recorded during 32^nd standard week in wooden block traps. A significant positive correlation was evident between trap catch data and minimum temperature (r = 0.57) and relative humidity (r = 0. 71) in suspension traps, as well as in wooden block traps (r = 0.64 and 0.65, respectively).