Revista Brasileira De Herbicidas 2012; 11(1): 49-61
Ipomoea hederifolia control with low volume using adjuvant spray liquid with spray rotary nozzle
The use of scientific knowledge that make possible the characterization and choice of spray nozzle suitable to control of biological target is a function of application technology. This work aimed to characterize the volumetric distribution, the spacing between nozzles, the diameter and uniformity of droplets produced by spraying nozzle of centrifugal energy and control in post-emergence of I. hederifolia with herbicide diuron + hexazinone (1170 g ha-1 + 330 g ha-1) using spray volumes of 20 and 40 L.ha-1 with or without addition of adjuvants (organosilicone – 0,025% v/v (Silwett) and vegetable oil – 1% v/v (Veget Oil). Treatments with use of rotative jet Herbi-4® model were compared to the check with hydraulic nozzle TT110.01 (150 L ha-1). Weeds control, volumetric median diameter (VMD), the percentage of droplets below 100 μm (% 100 μm) diameter and relative amplitude (RA) were evaluated. The addition of adjuvants to spray solution did not increase I. hederifolia control. The nozzle of centrifugal energy (model Herbi-4) has significantly reduced the risk of drift towards the use of hydraulic nozzle TT110.01, due to increase diameter of droplets, reducing the percentage of droplets less than 100μm and greater uniformity of droplet size, despite a pattern of distribution to be no uniform. There was no difference in I. hederifolia control between rotative jet Herbi-4® and hidraulicnozzles TT110.01.
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