Deriva do herbicida 2,4-d aplicado com pontas hidráulicas de jato plano tipo leque

Abstract

Drift is one of the major problems in the application of agrochemicals, often responsible for the low efficiency of controls. The objective of this study was to analyze the 2,4-D herbicide drift applied with fan-type flat jet hydraulic tips. Two solutions were evaluated: water and water + 2,4-D and four tips: simple fan (JS), simple fan with pre-orifice (JSPO), simple fan with induction (JSIA) and double fan with induction (JDIA). The diameter of the volumetric median (DMV), relative amplitude (SPAN), and percentage of droplets with a diameter less than 100 ?m (V < 100) were analyzed in a laser analyzer and drift in a wind tunnel. Data were submitted to ANOVA and Tukey’s test at 5%. The tips JS, JSPO, JDIA, JSIA, in this order, generated decreasing percentages of V < 100 and drift. Addition of 2,4-D decreased 16% drift at the tip with JSPO and increased 26% at the tips with induction. At the tips with induction, the JDIA generated higher V < 100 and lower DMV, and consequently greater drift, in relation to JSIA. In induction tips, the presence of 2,4-D increases the drift and the double fan provides greater drift compared to the single fan. Regardless of the presence of 2,4-D, tips with induction are more efficient in drift reduction over pre-bore.