Formulation and Field Efficacy of Nano-Emulsified Insecticides for Sustainable Pest Control in Cotton Against Helicoverpa Armigera

Abstract

The traditional pesticidal compounds have severe constraints such as low solubility, environmental persistence, and non-target toxicity. This paper examined the formulation of nano-emulsified      lambda-cyhalothrin and efficacy against Helicoverpa Armigera (Hubner) infesting cotton (Gossypium hirsutum L.) using this formulation. Mean particle size of 126 ± 12 nm and zeta potential of -34.2 mV were obtained by using ultrasonication (20 kHz, 15 min) as the surfactants: Tween 80 and Span 20, to prepare nano-emulsion. Field experiments were carried out at Research Farm, CCS HAU Hisar, in kharif 2022 and 2023, which compared 5 treatments: nano-emulsion at 10,15, and 20 g a.i./ha; commercial EC formulation at 20 g a.i./ha; and no treatment. Three replications of the randomized complete block design were adopted. At 20 g a.i./ha, 89.3% larval kill at 7 days after treatment was achieved in nano-emulsion, which was considerably higher than that of the EC formulation (76.8%). Average boll damage was decreased to 8.4%. in comparison to 15.2 %. using EC formulation with 22.7%. Higher seed cotton (2,847 kg/ha). The nano-formulation was found to have better foliar adhesion, rainfastness, and UV stability. The cost-benefit analysis provided more returns of 18420/ha. Findings demonstrate that nano-emulsification is an effective approach to minimizing pesticide dosage without reducing efficacy, which fits the sustainable crop protection agenda.