Dose Response of Some Chemical Insecticides in Mitigating Shoot and Fruit Borer (Earias vittella Fab.) Infestation in Okra

Abstract

Okra (Abelmoschus esculentus L.), a highly consumed summer vegetable in Bangladesh, is detrimentally affected by the shoot and fruit borer, Earias vittella (Fab.) (Family: Noctuidae, Order: Lepidoptera). The current study was conducted to explore the dose effect of some chemical insecticides, viz., Belt 24 WG (flubendiamide), Voliam Flexi 300 SC (chlorantraniliprole + thiamethoxam), and Pine 6 WG (emamectin benzoate + abamectin) @ (0.25, 0.50, and 0.75) g or ml litre-1 of water with an untreated control against this notorious pest. Results revealed that Pine 6 WG @ 0.75 g litre-1 of water reduced the highest percentage of shoot infestation (66.58% & 75.94%) over control at vegetative and fruiting stages, respectively, followed by Pine 6 WG @ 0.50 g litre-1 of water (58.35% & 75.94%, respectively), whereas Belt 24 WG @ 0.25 g litre-1 of water showed the least performance (42.51% & 63.05%) in shoot infestation reduction for both stages of the crop, respectively. At the early, mid, and late fruiting phases, the least number of infested fruits was generated by Belt 24 WG @ 0.25 g litre-1 of water, with numbers of 1.08, 0.83, and 0.79, respectively. With a 51.50% increase over the control, Pine 6 WG @ 0.50 g litre-1 of water produced the maximum fruit output (19.56 ton ha-1). In conclusion, the study demonstrated that utilizing Pine 6 WG @ 0.75 g litre-1 of water successfully mitigated shoot and fruit borer infestations in okra, making this insecticide a promising method for controlling this pest.