author(s)
Srinivas MP, Suchithra Kumari MH, Hanumantharaya L, Thippeshappa GN and Yalleshkumar HS

abstract
Field experiment on the effect of different insecticides against fruit fly, Bactrocera cucurbitae (Coquillett) infesting cucumber was carried out during kharif 2017 and summer 2018 at Chikkamagaluru. The results revealed that significantly lowest number of ovipositional punctures (0.72 and 0.98 /fruit), lowest number of maggots (8.0 and 8.93 /fruit), lowest percent fruit infestation (14.92 and 17.90 %), highest marketable fruit yield (15.63 and 16.49 t/ha.) and more cost-benefit ratio (1: 2.30 and 1: 2.43) was recorded in the treatment with spinosad 45 SC (0.15 ml/l) during both kharif and summer season, respectively and it was on par with the treatment dichlorvos 76 EC (1.0 ml/l). However, highest number of ovipositional punctures (2.72 and 3.01 /fruit), highest number of maggots (19.13 and 19.80 /fruit), highest percent of fruit infestation (46.91 and 56.79 %) and lowest marketable fruit yield (10.75 and 9.01 t/ha.) was obtained in the jaggery treatment (10 g/l) which was followed by control in both kharif and summer season, respectively. During the kharif season the lowest cost-benefit ratio (1: 1.62) was obtained in jaggery treatment while in summer season cyantraniliprole 10.26 OD recorded the lowest cost-benefit ratio (1: 1.34).