COMPARATIVE EFFECTIVENESS OF NEEM EXTRACTS AND SYNTHETIC ORGANIC INSECTICIDE AGAINST MUSTARD APHID

Effectiveness of different doses of neem extracts and a synthetic organic insecticide against mustard aphid was studied in the experimental farm of the Oilseed Research Centre, Bangladesh Agricultural Research Institute (BARI), Joydebpur, Gazipur, during two consecutive years 2010-2011 and 2011-2012 for the control of mustard aphid. Eight treatments were evaluated against mustard aphid under field condition. The maximum aphid population was (180 per plant) observed at the pod formation stage of mustard crop. Among the treatments, Malataf (Malathion 57EC) @ 2ml/l significantly reduced the highest aphid population (93.75%) over pretreatment which produced the highest seed yield (1440 kg/ha) of mustard. The neem leaf extracts reduced 63.16-72.55 % aphid population in mustard while neem seed extract reduced 73-81 % aphid population over pretreated plants in both the years. Among the different doses of neem extracts, the highest aphid population reduction over pretreatment (81%) was recorded from 50g neem seed per litre of water treated plots with high MBCR (3.88) followed by 75g neem seed/l treated plots having reduction of 80 % and MBCR 3.78