Effectiveness of the mixture picloram and fluroxypyr on the control of perennial weeds of tropical grasslands.
During 2001 an experiment was established in three locationsof the central and northern areas of the state of Veracruz,Mexico. The objective was to assess the effectiveness of theformulated mixture of the herbicides picloram + fluorxypyr inthe control of Sida acuta Burm f., Croton reflexifolius Kunt...
|Main Authors:||Esqueda Esquivel, Valentín Alberto, Tosquy Valle, Oscar Hugo, Rosales Robles, Enrique|
Universidad de Costa Rica
During 2001 an experiment was established in three locationsof the central and northern areas of the state of Veracruz,Mexico. The objective was to assess the effectiveness of theformulated mixture of the herbicides picloram + fluorxypyr inthe control of Sida acuta Burm f., Croton reflexifolius Kunthand C. cortesianus Kunth, three perennial weed speciescommon in tropical grasslands. The mixtures of picloram +fluroxypyr at 40 + 40, 60 + 60 and 80 + 80 g a. i./100 l water;picloram + 2,4-D at 64 + 240 and 96 + 360 g/100 l water andpicloram + metsulfuron methyl at 64 + 4 g/100 l water wereevaluated in a Randomized Complete Block Design with fourreplications. The effect of the treatments on the control of thethree weed species and on the toxicity to the forage grasseswas determined. The best control of S. acuta and C.cortesianus were obtained with the highest and medium ratesof picloram + fluroxypyr, with average values higher than90%. This herbicide mixture had a significantly higher controlthan the picloram + 2,4-D and picloram + metsulfuron methyltreatments. With the highest rates of picloram + fluroxypyr andpicloram + 2,4-D, C. reflexifolius was controlled 55 and 46%,respectively; these mixtures were statistically similar betweenthem. None of the herbicide treatments caused any toxicity tothe forage grasses. It was concluded that applications of atleast 60 + 60 g a. i./ha. of picloram + fluroxypyr are requiredto have a good control of S. acuta and C. cortesianus.