Capacity of detergent to increase the efficacy of bio-pesticides and chemical pesticides against giant mealybug, Drosicha mangiferae (Homoptera: Pseudococcidae)

The giant mealybug, Drosicha mangiferae, is a pest that affects various important tropical fruits, vegetables, and ornamental plants. Its waxy body provides resistance against insecticides, making effective control challenging. This study investigated the effectiveness of biopesticides and chemical insecticides, both alone and in combination with detergent application. The biopesticides, D-limonene and Matrine, showed varying levels of effectiveness. Chemical pesticides also varied in effectiveness after detergent application. The LT₅₀ values for Abamectin and Chlorpyrifos were significantly reduced; for instance, Abamectin’s LT₅₀ changed from 2568.80 h to 273.39 h, and Chlorpyrifos went from 443.66 h to 9.64 h. Detergents notably improved pest control efficiency (LT₅₀ of Abamectin: 2568.80 vs. 273.39 h; Chlorpyrifos: 443.66 vs. 9.64 and 2161.10 vs. 4.70 h). The presence of detergent reduces the LT₅₀ by a large margin, indicating enhanced pest control efficiency. Carbosulfan, Beta Cyfluthrin + Imidacloprid, and Cypermethrin showed lower LT₅₀ values, suggesting faster control when used alone. For instance, Carbosulfan had an LT₅₀ of 2.59 h, Beta Cyfluthrin + Imidacloprid had 3.31 h, and Cypermethrin had 5.71 h. Sequential use with detergent slightly lowered their LT₅₀ values, further improving their control efficiency, with values of 2.73 h hours for Beta Cyfluthrin + Imidacloprid and 4.77 h for Cypermethrin. The findings highlight the benefits of using detergents before applying pesticides. However, the potential harm of detergents to plants must also be considered to ensure sustainable pest management practices and minimize environmental impact.