Spray drift with several nozzles under wind breeze in a vineyard nursery

Abstract

The area planted with grapes in Chile has grown nearly 50 % in the last 12 years, causing a drastic increase in use of agrichemicals. In particular, herbicides need to be applied more precisely to reach the desired targets. Weeds are a limiting factor in nurseries, mostly because of the reduced distance between rows. The spray nozzles are of vital importance because they distribute the mixture over the target. A comparative study between conventional extended rage flat spray (XR) and drift reducing nozzles (TT, DG and AI) was conducted in Vitis vinifera L. cv. Thompson Seedless plants self-rooted in the nursery, studying the drift detection and quantification, of a 5.8 km.h-1 wind breeze, using the food tracer Brilliant Blue FD & C-1. Under this breeze condition, at the plants level, the drops produced with the XR nozzle suffered a trajectory deviation. A strong decrease in the spray deposits occurred while the spray area distance increased. At ground level, it was appreciated that with wind conditions, there is an increase in all the nozzles of the tanks before the plant, next to it, and after cultivation, but these did not become statistically significant at this wind level