Residue height and interval between harvest and nitrogen fertilization of Mombasa Grass

Abstract

The objective was to identify the adequate moment, after defoliation, to apply nitrogen fertilizer to Mombasa grass and to verify if the height of the residue influences the moment of fertilization. Experiment was conducted in the greenhouse of the Federal University of Rondonópolis. The Panicum maximum cv. Mombasa cultivar was used. Experimental design was entirely randomized, with four treatments and ten repetitions, arranged in a 2x2 factorial scheme. Threatments consisted of two intervals between defoliation and nitrogen fertilization (0 and 7 days) and two residue heights (20 and 40 cm). The following variables were evaluated: height, number of leaves and tillers, forage dry mass, leaf blade emergence rate, phyllochron, growth rate. The timing of fertilization did not alter the development of Mombasa grass, which demonstrated that Mombasa grass is flexible as to when to perform nitrogen fertilization. Since the timing of fertilization did not alter forage mass, when fertilization is performed immediately after defoliation or up to seven days later, no change in the carrying capacity of the pasture is expected.  Therefore, nitrogen fertilization in Mombasa grass can be performed at any time, either on the day or one week after defoliation. However, attention should be paid to the height of the residue, in order to promote an adequate residual leaf area for regrowth and tillering of the grass.