Abstract

ESQUEDA ESQUIVEL, Valentín A.  and  TOSQUY VALLE, Oscar Hugo. Effect of volume and pH of water to control Ixophorus unisetus (J. Presl) Schltdl. with glyphosate. Rev. Mex. Cienc. Agríc [online]. 2015, vol.6, n.1, pp.97-109. ISSN 2007-0934.

Two experiments were established to determine the effect of volume and pH of spray water in controlling grass Ixophorus unisetus with various doses of the herbicide glyphosate. The experiment was located in Medellin, Veracruz, Mexico, in a randomized block design with four replications and arrangement of treatments in a split plot. In both experiments, large plots corresponded to three doses of glyphosate (267, 356 and 712 g ha^-1), while the split plots in experiment 1, corresponded to four volumes of application (133, 217, 294 and 370 L ha^-1) and on experiment 2 four pH levels (5, 6, 7 and 8). Control of I. unisetus at 7, 15 and 30 days after application (DAA) was evaluated and the dry weight of the aerial parts at 30 DAA were determined. The application of glyphosate at 712 g ha ^-1 had the highest control of I. unisetus. The effectiveness of the herbicide was greater when applied with a water volume of 217 or 294 L ha^-1 or the pH of this varied between 5 and 7. Control of I. unisetus was reduced with a dose of 267 g ha^-1, using a water volume of 370 L ha^-1 or when pH of water was 8. Dry weight of I. unisetus was significantly lower with doses of 356 and 712 g ha^-1 of glyphosate, whereas the volume and pH of water had no influence on this variable.

Keywords : Ixophorus unisetus; chemical control; dry weight.