Insecticide spray drift reduction with different adjuvants and spray nozzles

Rodrigo Y. P. Marubayashi,Marcelo da C. Ferreira,Otavio J. G. A. Saab,Samuel Roggia,Eder D. de Moraes,Rone B. de Oliveira

doi:10.1590/1807-1929/agriambi.v25n4p282-287

Abstract

ABSTRACT Insecticide spray drift can lead to reduced control efficiency and loss of product to the environment. Thus, we conducted a study to evaluate the effect of different spray nozzles and the addition of adjuvants in insecticide spray on the resulting droplet spectrum and wind tunnel drift. All experiments were conducted in a completely randomized design with four repetitions using a 5 × 3 factorial scheme. Five spraying solutions were studied; one contained only water and the other four comprised thiamethoxam + lambda-cyhalothrin (no adjuvant, Oro-solve, Wetcit Gold, and Orobor N1), in combination with three spray nozzles (AXI, JFC, and J3D). The droplet spectrum was evaluated through the volumetric median diameter, relative amplitude, and percentage of the droplet volume with diameter ≤ 100 µm. The drifts were evaluated in a wind tunnel at 5, 10, and 15 m. Data were subjected to analysis of variance and means were compared using the Tukey’s test. In addition, a principal component analysis was performed. Application of the insecticide with the adjuvants combined with the different nozzles changed the droplet spectrum and the risk of drift. The AXI nozzle and the J3D associated with the Oro-solve and Wetcit Gold adjuvants resulted in a greater volumetric median diameter of the droplets and drifts were observed at 5 m.

Highlights

The spraying of insecticides to control brown stink bugs in soybean agriculture is predominantly carried out when plants reach a maximum leaf area, requiring applications with maximum capacity to penetrate the leaf mass and cover the surface (Antuniassi et al, 2004).In order to successfully apply phytosanitary products, it is necessary to master the appropriate techniques to ensure that the product reaches the target efficiently, thereby minimizing losses and reducing environmental contamination (Cunha et al, 2005)
There was a significant effect of the interaction between the spray solution and nozzle in the variables volumetric diameter (VMD), RS, and Drops ≤ 100 (Table 2)
These results corroborate those found by Ferreira et al (2013), who observed that the effect of adjuvants on the droplet spectrum was dependent on the interaction between the product and the spray nozzle used

Summary

Introduction

The spraying of insecticides to control brown stink bugs in soybean agriculture is predominantly carried out when plants reach a maximum leaf area, requiring applications with maximum capacity to penetrate the leaf mass and cover the surface (Antuniassi et al, 2004).In order to successfully apply phytosanitary products, it is necessary to master the appropriate techniques to ensure that the product reaches the target efficiently, thereby minimizing losses and reducing environmental contamination (Cunha et al, 2005). The formation of droplets on the nozzles is often quite uneven (Cunha et al, 2007) This can be mitigated by adding adjuvants to the spray solution (Thebaldi et al, 2009) to alter its physico-chemical characteristics (Antuniassi, 2006). This can affect both the application mode and the activity of the chemical product (Aguiar Júnior et al, 2011), and reduce the number of drops susceptible to drift (Oliveira et al, 2015)

Methods

Results

Conclusion