Shonga et al Greener Journal of Agricultural Sciences Vol. 3 (7), pp.569-578, July 2013. ISSN: 2276-7770 Research Paper Manuscript Number: 061213667 Effect of Insecticide Rotation and Mixtures Use for Resistance Management on Cotton Aphid, Aphis gossypii Glover (Hemiptera, Aphididae) in Middle Awash Areas of Ethiopia Ermias Shonga,1* Kemal Ali2 and Ferdu Azrefegne3 1Entomologiest, Hawassa Agricultural Research center. 2Entomologist; Holeta Agicultural Research Center, Ethiopian Institute of Agricultural Research (EIAR). 3Entomologist, Hawassa University College of Agriculture (HU), Po Box 06, Hawassa, Ethiopia. 3Email: fazerefegne@ hotmail. com *Corresponding Author‘s Email: ermishon @ yahoo. com, Fax: +251462200084, Tel: +251912011604 Abstract: A field experiment was conducted at Werer Agricultural Research Center, Afar region, Ethiopia, to determine the best insecticide rotation sequence and use of compatible mixtures in the Insecticide Resistance Management strategy for cotton aphid, Aphis gossypii. Randomized Complete Block design having eight treatment combinations and four replications were used. The parameter assessed were aphid population at pre and post insecticide application; and seed cotton yield. In this experiment, four round of spray application was made by using insecticides from different chemical class and their mixtures. Using the modified Abbott’s formula, the percent efficacy was computed. A highly significant difference (P< 0.001) was observed among the treatments for post spray counts. In most of the treatments made during the first round spray, the aphid population didn’t show a response to the insecticides applied. But starting the second round, the insecticides were able to express their potential in reducing aphid population. In most cases sole treatments were better than mixtures. However, the mixtures like endosulfan + carbosulfan and endosulfan + furathiocarb gave better control of aphid. As the effect of insecticide rotation, treatment 2 (Carbosulfan, Diafenthiuron, Furathiocarb and Deltamethrin), 3 (Dimethoate, Carbosulfan, Deltamethrin and Diafenthiuron) and 5 (Endosulfan, Endosulfan + Carbosulfan, Deltamethrin and Dimethoate) were the best alternative combinations of insecticide groups to be used in IRM strategy. Seed cotton yield was significantly different (P< 0.0001) among treatments. The highest seed cotton yield (29.84 q/ha) was recorded from treatment 5 (Endosulfan, Endosulfan* Carbosulfan, Deltamethrin and Dimethoate), followed by treatment 1(Endosulfan, Carbosulfan, Deltamethrin and Furathiocarb) and 7 (Furathiocarb Endosulfan * Furathiocarb, Deltamethrin and Dimethoate) and yielding 26.29 and 20.47 q/ha, respectively. These findings point to the fact that, alternative use of insecticides from different class and using insecticide mititures is the best option to manage insecticides resistance in cotton aphid. Keywords: Cotton aphid (Aphis gossypii), insecticide resistance management, Ethiopia. Return to Content View Reprint (PDF) (994KB)