Efficiency of Certain Neonicotinoid Mixtures Against the Cowpea Aphid, Aphis craccivora (Koch)

Abstract

Insecticide combinations are a strategy for increasing toxicity, combating resistance, and overcoming resistance. Neonicotinoid mixtures have been recommended to control a variety of sucking insects. In this study, the combination index (CI) was used to examine the synergistic interactions of certain neonicotinoids (acetamiprid, thiamethoxam, and dinotefuran) with various insecticides. The interactions of neonicotinoid mixtures were assessed by using the experimental combinations (1:1) and the commercial formulation mixtures ratio. The results clarified that the combination between neonicotinoids and acetylcholinesterase inhibitors insecticides had a strong synergistic effect, with (CI) values ranging between 0.05 -0.56. On the other hand, the lowest combination index (CI) value was 0.05 in thiamethoxam/profenofos mixtures, indicating the strongest synergism. Likewise, similar results were obtained with the antifeedant pymetrozine, with CI values ranging between 0.34- 0.68. Neonicotinoids had an additive effect when mixed with the tested pyrethroids and abamectin. Synergized mixtures can help to establish a resistance management strategy, reduce costs, and provide broad spectrum activity to cover multiple target pests at the same time.