Potential Drift and Injury of Herbicides Sprayed in a Wind Tunnel

Abstract

The possibility of synthetic auxin applications in crops increases the risk of injury to sensitive plants. The aim of this study was to quantify the drift of herbicides sprayed in a wind tunnel and the injury in cotton plants. The experimental design was a completely randomized design with five treatments and four replications. The tested spray solutions were dicamba (0.250 L c.p. ha −1), glyphosate (0.625 L c.p. ha −1), 2,4-D (0.250 L c.p. ha −1), glyphosate + 2,4-D (0.625 L c.p. ha −1 + 0.250 L c.p. ha −1), and glyphosate + dicamba (0.625 L c.p. ha −1 + 0.250 L c.p. ha −1). Drift was quantified in a wind tunnel, collected at distances of 5, 10, and 15 m in relation to the spray tip. Cotton plants were placed in the same wind tunnel and the injury was visually evaluated for at 3, 7, and 15 days after application (DAA). The addition of glyphosate to dicamba and 2,4-D potentiated the drift from 5 m. At 10 and 15 m, dicamba and 2,4-D in isolation had the lowest drift potential. At 5 m, the injury is higher than at other distances regardless of the spray solution. At 10 m, 2,4-D in isolation presented the highest injury when compared to dicamba in isolation at 7 and 15 DAA. At 10 and 15 m, the addition of glyphosate to dicamba enhances the injury in cotton plants and herbicide mixtures do not differ from each other in relation to injury.

Effect of 2,4-D sub-dose on the initial development of common bean crop

“…L -1 presented injury greater than 80%, considering a satisfactory control index from this value (Figure 3B). The injuries observed from sub-doses resulted in swelling of the tissues, hyponastic response of the petioles, chlorosis and necrosis of leaves and stems (GROSSMANN, 2010;OLIVEIRA et al, 2019), since synthetic auxin cause cellular disorganization of the mesophile (PAZMIÑO et al, 2011).…”

Potential of preventive bioremediation to reduce environmental contamination by pesticides in an agricultural context: A case study with the herbicide 2,4-D

“…After only one day of incubation, significant differences in leaf-coverage were observed between treatments (P < . This is not surprising because, although wheat is not sensitive to 2,4-D, it has already been shown that this herbicide can impact wheat yield at all growth stages, mainly due to a decrease in the number of kernels per spikelet and a reduction of the numbers of spikes per plant and spikelets per spike (Pinthus and Natowitz, 1967;Islam et al, 2018;Oliveira et al, 2019;Scholtes et al, 2019).…”

“…The preventive bioremediation could also provide the means to better protect the culture and avoid a decrease of productivity. Some studies have evidenced 2,4-D causing many injuries to crops, despite its theoretical selectivity (Islam et al, 2018;Oliveira et al, 2019;Scholtes et al, 2019).…”

Phytotoxicity in soybean crop caused by simulated dicamba drift

“…To achieve profitable yields, pests and diseases that attack soybean crops need to be controlled, as do the weeds that compete for light, water, and nutrients. The application of herbicides is the primary method of weed control (Oliveira et al, 2019). However, the inappropriate use of these products has led to the emergence of many cases of weed resistance (Heap, 2019), especially after the development of glyphosatetolerant soybean cultivars.…”