Effect of Simulated Glyphosate Drift on the Initial Growth of Physic Nut Plants

This work aimed to evaluate the effect of simulated glyphosate drift on the initial growth of physic nut plants (Jatropha curcas) under greenhouse conditions. The experimental design was a randomized block with four replications. To simulate drift, glyphosate was used at the following rates: 0.0, 1.4, 2.8, 5.6, 11.3, 22.5, 45.0, 90.0, 180.0 and 360.0 g ha(-1), distributed in randomized blocks with four replications. Glyphosate was applied 51 days after sowing, when the plants displayed between 16 and 18 fully developed leaves and 45 cm height. A backpack sprayer was used, pressurized to CO2 and adjusted to provide spraying consumption of 200 L ha(-1). The results indicated that height, stem diameter, leaf area and dry mass of leaf, stem and root of the physic nut plants showed reductions after glyphosate drift simulation, compared with the control. Thus, it can be concluded that the initial growth of the physic nut plants was influenced by simulated glyphosate drift, and that the drift of rates higher than 45.0 g ha(-1) can cause severe damage to the plants during the period of 41 days after application.