Produtividade da Brachiaria brizantha cv. Xaraés em diferentes manejos e doses de aduba？？o, períodos de descanso e épocas do ano

in experiments conducted in the eastern part of minas gerais in brazil to evaluate the forage grasses, brachiaria brizantha cv. xaraes proved to be exceptional. thus, it was decided intensify the research on this grass, conducting an experiment in a sub-split-plot, and plots a 2 x 2 factorial (seasons and management of fertilization), four rest periods in the subplots and six levels of fertilization in the sub-subplots, in a completely randomized design with four replications. the seasons were fall/winter and spring/summer. the rest periods were 21, 28, 35 and 42 days. the management consisted of application of nitrogen and potassium fertilizers scattered conventional and fertigation. to differentiate the dose of fertilization in the treatment fertirrigated, it was used a line-source irrigation system. the fertilization doses had a ratio of nitrogen and potassium, 1 n: 0.8 k2o and were 0, 15, 39, 64, 83 e 100% of the reference (700 e 560 kg of n and k2o). dry matter was obtained by means of the dry material in ventilated stoves at 60 °c, for 72 h. the dry season had dm yield, but on average, the yield in the autumn/winter was 75% of that obtained in the spring/summer. the management of fertilization did not influence the values of dm yield, but increasing the dose of fertilization has positive linear effect on xaraes-grass fertigated in the autumn/winter and quadratic in the other treatments. the rest periods provided quadratic effect only in the treatment fertigated in fall/winter season.