The Effectiveness of Certain Insecticides and Combined Activities Against Adult Cowpea Beetles

Abstract

Callosobruchus maculatus is a common pest in legume fruits. Herein, this study was conducted to evaluate the toxic potential of certain chemicals against cowpea beetle using filter paper and dipping seeds bioassays. As a result, carbosulfan, a carbamate insecticide, was the most toxic, followed by indoxacarb and malathion. The LC50 values varied in both tested bioassays. In general, in filter paper contact and dipping seeds as residual bioassay, all tested insecticides categories have the same toxicity ranking. Whilst neuro insecticides have the first ranks, the IGRs have the later ranks. These results suggest certain tested insecticide is more suitable in contact, while others are more effective in mixing with seeds such as thiamethoxam. While carbosulfan and malathion are good candidates as store or seed protectant agents. Also, the emamectin benzoate and spinosad are promised ecofriendly agent as contact and residual effects as protectant against storage insect pest. Neuro insecticides were the highest toxicity among the tested insecticides, while IGRs have the lowest. Some insecticides are more suitable for contact, while others are more effective in mixing with seeds. Emamectin benzoate and spinosad are eco-friendly agents for contact and residual effects. Synergistic activity was detected in thiamethoxam, lemongrass oil, jojoba oil, and flaxseed oil.