Innovative air assisted electrostatic sprayer for managing jassids (amrasca biguttula biguttula Ishida) and aphids (aphis gossypii Glover) in cotton

Jassids and aphids are major sucking pests of cotton. These pests typically feed on the undersides of leaves. Consequently, chemical insecticides are often less effective due to inadequate adsorption on the leaves caused by small droplet sizes and prevailing wind speeds during spraying. As a result, the droplets fail to settle on the crop canopy, reducing the efficacy of plant protection chemicals. To address these challenges, an induction-based air-assisted electrostatic sprayer was developed. This sprayer aims to achieve high deposition, uniform spray distribution, better coverage, and improved mortality of these target sucking pests. A method was developed to optimize the amount of pesticide by considering the combined influence of the plant, the pest, the pesticide, and the spray equipment on the bioefficacy of the treatment. The developed system was evaluated and compared with the existing knapsack sprayer in terms of droplet distribution and bioefficacy. The methodology involved optimizing pesticide application by considering the combined effects of the plant, pest, pesticide, and spray equipment on treatment bioefficacy. The developed induction-based air-assisted electrostatic sprayer was then evaluated and compared to a conventional knapsack sprayer for droplet distribution and bioefficacy against aphids and jassids.The electrostatic sprayer demonstrated 85% efficacy against aphids and 92% efficacy against jassids in 2020, slightly lower in 2021 (78% against aphids and 87% against jassids). Mortality rates for aphids were 88% (2020) and 91% (2021). Knapsack sprayer had mortality rates of 81% (2020) and 86% (2021) for aphids. The study highlights the importance of establishing pesticide guideline values for aphid and jassid control in cotton using bioassay indices. It proposes a method to calculate optimal lethal doses and suggests the use of electrostatic charging to reduce pesticide usage, promoting efficient and eco-friendly pest control.