The structure of the sward is important because it influences the responses of plants and animals in grazing conditions. The objective with this work was to evaluate the structural characteristics of the Marandu palisade grass pasture (Brachiaria brizantha syn. Urochloa brizantha) during spring and summer, depending on the condition of the sward at the end of winter. Four grazing conditions at the end of winter were evaluated: short (24.1 cm), short (25.2 cm)/mown (8 cm), tall (49.0 cm) and tall (50.0 cm)/mown (8 cm). The foliar area index was lower in the tall pasture than in the tall/mown pasture. The mass and the volumetric density of dead stem were higher in the tall pasture, intermediate in the short pasture, and lower in mowed pastures. At the beginning of the grazing period, the live stem mass was higher in the tall pasture. At the beginning and middle of the grazing period, the volumetric density of dead leaf lamina was lower in mowed pastures. At the beginning of the pasture period, the short pasture had a higher tiller number (TN). In the middle of the grazing period, the short and short/mown pastures had higher TN. At the end of the pasture period, the lowest TN value occurred in the tall pasture. The tall pasture at the end of winter presents an unfavorable structure to the animal in grazing, while the mowing and reduction in the height of the marandu palisade grass improves the structure of the sward in spring and summer.

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A adubação foliar com macro e micro minerais para o estabelecimento de gramíneas forrageiras pode ser uma alternativa menos onerosa ao produtor, contudo os possíveis benefícios dessa técnica de maneja ainda precisam ser melhor estudados. O objetivo deste trabalho foi avaliar as respostas fisiológicas, produtivas, estruturais de gramíneas do gênero, em função da aplicação ou não de adubo foliar durante o estabelecimento das plantas. Quatro experimentos foram conduzidos separadamente e concomitantemente, para avaliar, as seguintes gramíneas forrageiras: Urochloa brizantha cv. Marandu e os capins Mulato II, Mavuno e Ipyporã, híbridos de Urochloa. Os experimentos foram conduzidos de novembro de 2018 a março de 2019, em delineamento inteiramente casualizado, com quatro repetições. A área experimental de cada experimento consistiu de quatro parcelas com 12,25 m², onde metade da área das parcelas recebeu o adubo foliar (FH PASTAGEM FOLIAR, com 14% de N; 12% de P; 12% de K; 0,38 % de Mg; 10,2% de S; 0,24% de Cu; 0,18% de Mn e 0,63% de Zn) e a outra metade, não. O fertilizante foliar (2 kg ha-1) foi diluído em água e aplicado com pulverizador manual aos 42 dias após a emergência das plantas. Foram avaliadas as variáveis respostas: índice spad, índice de área foliar, interceptação de luz pelo dossel, produção de forragem e densidade de raiz. Em todos os experimentos, a aplicação do adubo foliar durante o estabelecimento dos capins Marandu, Mulato II, Mavuno e Ipyporã não influenciou os índices spad e de área foliar, a produção de forragem e a densidade de raiz.

Height and mowing of a sward in late winter can change its structure during the subsequent spring and summer seasons, which influences plant growth and animal performance. This work was conducted to evaluate the structural characteristics of Urochloa brizantha (syn. Brachiaria brizantha) cv. Marandu (marandu palisadegrass) during spring and summer in relation to the following sward conditions in late winter: short (15 cm), medium (23 cm), tall (31 cm) and tall (31 cm)/mowed to 8 cm. Stages of the grazing period (beginning, middle and end) in spring and summer were considered measures repeated over time. Leaf area index was lower in the tall pasture than in the other pastures and was lower at the beginning than at the end of the grazing period. Dead material mass was highest in the tall pasture, intermediate in the short and medium pastures and lowest in the tall/mowed pasture. Live stem mass was higher at the end than at the beginning and middle of the grazing period of the short, medium and tall/mowed pastures, contrary to that observed in the tall sward. At the end of the grazing period, tiller number did not vary among pastures. The tall pasture in late winter presents a limiting structure to animal consumption. Short and tall/mowed pastures in late winter show a favorable structure for forage plant growth and, probably, animal performance.

This study aims to evaluate the effects of height (15 and 30 cm)and nitrogen dose (N, 40, 80, and 120 kg ha-1) at the beginning of thestockpiling period on the structural characteristics of the Urochloabrizantha cv. Marandu (Marandu palisade grass) during winter. Thefalling index of the plant did not vary with the factors under scrutiny(P>0,10). The number of basal tillers was higher (P<0,10) in the 15-cmdeferred canopy than in the 30-cm canopy only when the highest N dosewas used. Under conditions of application of 0 or 80 kg ha-1 of N, the 30-cmstockpiled canopies showed a higher (P<0,10) forage mass than the 15-cmones. Associated with reduced canopy height at the beginning ofstockpiling period, nitrogen fertilization improves the morphologicalcomposition of Marandu palisade grass. To maximize the forage mass inthe dry season, the canopies of Marandu palisade grass can be deferredeither at 15 cm (fertilized with about 100 kg ha-1 of N) or at 30 cm (with nonitrogen fertilization) at the beginning of the stockpiling period.