TITLE:
How Much Do Adjuvant and Nozzles Models Reduce the Spraying Drift? Drift in Agricultural Spraying
AUTHORS:
Fabiano Griesang, Ricardo Augusto Decaro, Cícero Antônio Mariano dos Santos, Eduardo Souza Santos, Nelson Henrique de Lima Roque, Marcelo da Costa Ferreira
KEYWORDS:
Droplet Size, Uniformity of Droplets, Span, Volumetric Median Diameter, Safe Application
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.8 No.11,
October
24,
2017
ABSTRACT: The spraying of herbicides in crops has become the
main form of weed control. Although it means unexpected effects on non-target
plants resulted by spraying drift. Thus, improvements in application
techniques, as the best selection of spray nozzles and adjuvant, are essential to avoid environmental contamination and economic losses. On this work, we evaluate how much adjuvant associated with nozzles can
reduce the spray drift. The nozzles used at experiment were air induction flat
tip, hollow cone and twinjet and the spray liquids, which were composed of herbicide glyphosate and phosphatidylcholine +
propionic acid adjuvant. Measurements were made at wind tunnel and droplet
sizer, at laser diffraction method. The models of nozzles influence in droplet size characteristics and in
occurrence of spray drift. The use of adjuvants reduces the spray drift only
combined with the twinjet nozzle, while for the other models the adjuvant did
not reduce the global spray drift at significant levels. The adjuvant reduced
the spray drift until 39%, while the nozzles model reduced until 74%. Both
techniques when combined were able to reduce until 80%. The model of nozzle has the biggest result on drift mitigation and the
use of adjuvants can increase the drift mitigation specially with nozzles that
produces smallest droplets.