Residual efficacy of methoxyfenozide applied on different grain commodities for the control of three stored-product insect pests

Abstract

The residual efficacy of methoxyfenozide was assessed by exposing last instar larvae of Oryzaephilus surinamensis (Linnaeus, 1758) (Coleoptera: Silvanidae) , Tribolium castaneum Herbst, 1797 (Coleoptera: Tenebrionidae) and Trogoderma granarium Everts, 1898 (Coleoptera: Dermestidae) to the treated grain commodities (maize, oat, rice and wheat) at concentrations of 1, 2 and 4 mg kg -1 of active ingredient under laboratory conditions. This trial was performed at the Department of Entomology, University of Agriculture, Faisalabad, Pakistan during the year 2018. Six bioassays were conducted by releasing the insects on treated commodities after different post treatment periods (0, 2, 4, 8, 12 and 16 weeks). At 4 mg kg -1 , the adult emergence from larvae exposed to treated commodities did not exceed 15% at week 0 and it was less than 36% at week 12 in all the tested insect species on all the tested commodities. The methoxyfenozide was generally more effective on oats followed by wheat, maize and rice in the O. surinamensis and T. castaneum while against T. granarium it was more effective in wheat followed by oats, maize and rice. Results show that methoxyfenozide possess great potential for residual control of O. surinamensis, T. castaneum and T. granarium , and can be used for replacement of conventional neurotoxic insecticides.