Management of onion thrips by using border crop

抄録

Border crops have been employed as a cultural strategy to reduce pest populations. This management technique for controlling insect pests involves the use of secondary plants within or around a major crop. A field study was conducted during Rabi season of 2021-22 at Spices Research Centre, BARI, Shibganj, Bogura, Bangladesh (geographic coordinates 25.0167° N, 89.3167° E) to investigate the effect of border crop on thrips management and the activity of natural enemy of onion. Among various treatments, it was ovserved that an onion crop bordered by two rows of maize, with two spray interventions (first spray with Azadirachtin at 1 ml per litre at 7 weeks after transplanting (WAT) and second spray with Diafenthiuron at 1 ml per litre at 9 WAT), resulted in a lower thrips population (3.98 thrips/plant) and a higher bulb yield (18.06 t/ha). This treatment was significantly superior to all other treatments and farmers traditional practice. The greatest reduction in thrips population (70.08%) compared to the untreated control was also observed in the crop bordered by two rows of maize with Azadirachtin and Diafenthiuron treatments. Therefore, it is recommeded to use onion crop bordered by two rows of maize with two spray interventions (first spray with Azadirachtin at 1 ml per litre at 7 WAT and second spray with Diafenthiuron at 1 ml per litre at 9 WAT) for effective thrips management in onion.