Acaricidal efficacy of certain neem based pesticides against the red spider mite (Tetranychus urticae Koch) infesting okra

Overall result of two year's experiment conducted during summer, 2008 and 2009 revealed that out of nine neem based treatments, neem seed kernel extract (NSKE) 5 per cent applied as six round of foliar sprays proved to be the most effective in reducing the population of two spotted spider mite (Tetranychus urticas Koch) resulting in 88.80 per cent mite pest reduction. All other neem based formulated products almost remained at par in this regards, causing mite pest reduction ranging from 81.00 to 83.60 per cent (Neem Ban) (Rakshak Gold). The highest fruit yield (172.80 q ha⁻¹) of okra was obtained also in case of NSKE-5 per cent and other neem based formulations of pesticides viz. Neembecidine, Achook, Neemark, Neemguard, Rakshak Gold and Uttam Neem remained statistically at par in this regard. Neem Ban and Neemazal appeared to be little inferior to the neem products in terms of yield realization, inspite of their equivalent acaricidal efficacy against T. urticae. So far as the overall efficacy of both neem based and chemical pesticides tested under the experimentation, propargite 57 EC @ 1.250 l ha⁻¹ proved to the most efficacious against T. urticae infesting okra causing maximum reduction in the mite population to the tune of 81.50, 86.70 and 98.50 per cent recorded at 4,7 and 10 DAA (days after application). The maximum yield of 180.50 q ha⁻¹ also registered in case of propargite with minimum yield of 124.80 q ha⁻¹ which was obtained from the unprotected crop. The present findings suggest that NSKE (neem seed kernel extract) 5 per cent being the most effective against the mite pest could have the better place in IPM for eco-friendly management of T. urticae for sustainable cultivation of okra during summer season. Propargite can be used in the extreme situation of severe mite pest incidence.