An experiment was undertaken to know the effectiveness of different bio-rational insecticides for controlling brinjal shoot and fruit borer (Leucinodes orbonalis Guenee) under field conditions during winter season 2017-18. The different treatments were Bioneem 1% EC (Azadirachtin 1000ppm @1mlL- (T1) Noclaim 5 SG (Emamectin Benzoate) @1mlL- (T2), Tracer 45 SC (Spinosad) @0.4 1mlL-1 (T3), Suntec 1.8 EC (Abamectin) @1.2 1mlL-1 (T4) and untreated control (T5). Ours results revealed that the treatments Spinosad (T3), Abamectin (T4) and Emamectin Benzoate (T2) were effective to suppress brinjal shoot and fruit borer attacking brinjal shoot & fruit. The rate of shoot infestation was observed 6.25% and 26.01% in Spinosad (T3) treated plot and control, respectively. The lowest fruit infestation (6.98%) by number and (9.32%) by weight was recorded in Spinosad (T3) treated plot. The rate of reduction of fruit infestation over control was 82.82, 51.19, 41.15 and 38.17% by number and 66.11, 43.75, 33.13 and 24.44% by weight in Spinosad (T3), Emamectin Benzoate (T2), Abamectin (T4) and Azadirachtin (T1), treated plot, respectively. The yield in different treatments ranged from 22.02 - 32.52 t/ha. Healthy fruits yield increase over control varied from 19.36 to 85.46%, where the highest increase was found in Spinosad (T3) treated plot and the lowest in Azadirachtin (T1). The highest adjusted net return and Benefit Cost Ratio of Tk. 2,61564 and 11.08, respectively were obtained from Spinosad (T3) treated plot. The lowest Benefit Cost Ratio was 2.66 in Azadirachtin (T1) treated plot. Among the four bio-rational inecticides Tracer 45 SC (Spinosad) shown highest efficacy and it could be used against brinjal shoot and fruit borer in brijal production.
Key words: Brinjal, shoot and fruit borer, bio-rational insecticides, management
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