Glyphosate rates in the desiccation of Urochloa ruziziensis preceding corn planting

Abstract

The Urochloa ruziziensis stands as a fodder alternative for the straw development in the tillage system. However, there are few information regarding to the management of desiccation, and the effect of the straw on the weed control. This study aimed at evaluating the efficacy of glyphosate into the management of desiccation of the U. ruziziensis, and the effect of the straw on the weed suppression in corn plantation. The experimental design was a randomized complete block with four replications. The treatments consisted of the following rates of glyphosate: 0; 360; 720; 1,440; 2,160 and 2,880 g ha^-1, besides a testimony in fallow, and another in corn without straw. There was no influence of the U. ruziziensis straw in the development and the productivity of corn plants. The dose of 360 g ha^-1 of glyphosate provided 100% of of U. ruziziensis desiccation at 28 days after its application, while the remaining straw (6.5 t ha^-1) promoted 72.1% of reduction of the weeds population in the fallow portion at 30 days after the corn harvest. We concluded that the glyphosate doses evaluated were effective in the management of the U. ruziziensis desiccation, as well as, it can be an excellent alternative for the integrated management of the weeds in corn tillage system.