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Objetivou-se com este trabalho avaliar a produção de forragem e as características morfogênicas e estruturais do Panicum maximum cv. BRS Tamani, em função de doses de nitrogênio e intensidades de corte. O experimento foi conduzido em casa de vegetação. Foram avaliadas quatro doses de nitrogênio (0, 50, 100 e 200 mg/dm-³) e duas intensidades de corte (5 cm e 15 cm), em esquema fatorial 4 × 2, num delineamento inteiramente casualizado com quatro repetições. A taxa de alongamento foliar do capim BRS Tamani foi influenciada pela adubação nitrogenada, com resposta linear e positiva. Não foi observado efeito da intensidade de desfolhação para essa variável. A duração de vida da folha foi influenciada pela adubação nitrogenada, pela intensidade de desfolhação e pela interação entre os fatores. As características morfogênicas do capim BRS Tamani são influenciadas pela adubação nitrogenada. Plantas com maior aporte de nitrogênio alongam maior número de folhas, sendo o intervalo de aparecimento menor. Em ausência de adubação nitrogenada o capim BRS Tamani mantem as folhas vivas por mais tempo e em menor número. Plantas de capim BRS Tamani cortadas mais intensamente apresentam maior número de perfilhos. A adubação nitrogenada aumentou a produção de forragem da parte aérea de capim BRS Tamani, sem efeito na produção de raiz. Plantas submetidas a cortes mais intensos (5 cm) apresentaram maior produção de matéria seca da parte aérea. The objective of this work was to evaluate the forage production, and the morphogenic and structural characteristics of Panicum maximum cv. BRS Tamani, as a function of nitrogen doses and cut intensities. The experiment was conducted under greenhouse conditions. Four nitrogen doses (0, 50, 100 and 200 mg/dm³) and two cut intensities (5 cm and 15 cm) were evaluated in a 4x2 factorial in a completely randomized design with four replicates. The leaf elongation rate of the Tamani grass was influenced by nitrogen fertilization, with a linear and positive response. No effect of defoliation intensity was observed for this variable. The leaf life had a negative linear influence of the nitrogen fertilization without effect of the defoliation intensity. The morphogenic characteristics of the Tamani grass are influenced by nitrogen fertilization. Plants with greater nitrogen supply lengthen more leaves, with a shorter appearance interval. In absence of nitrogen fertilization the BRS Tamani grass keeps the leaves alive longer and in smaller numbers. More intensely cut BRS Tamani grass plants have a greater number of tillers. Nitrogen fertilization increased forage yield of BRS tamani grass, with no effect on root production. Plants submitted to moreintense cuts (5 cm) presented greater dry matter production of the aerial part.

Since the 1970s, common Urochloa (syn. Brachiaria) humidicola seeds have been an important part of the Brazilian market of cultivated tropical pasture seeds. Most of these seeds come from pasture areas in which animals are excluded from spring to harvest in summer. Commercial productivity is low and variable, especially because of the lack of appropriate management of seed production. Production is impaired in heterogenous lawns in terms of ground cover, height and constitution. An automatic harvester is the most widely used harvesting method, which is known to be inefficient in recovering the seeds produced. The use of this equipment is also limited in this species by the strong association between flowering synchronization and natural seedfall, which results in a short period of attachment of the seeds to the inflorescences. Thus, this harvesting method can only be used for 5-7 days during each harvest. The anticipation or delay of the reproductive phase of plants obtained by distinct agronomic management may permit the temporal distribution of production during the same harvest. The objective of this study was to evaluate the effects of cultural practices on the productivity, quality and harvest window of common U. humidicola seeds. The effects of cutting height (5 and 15 cm above ground level, respectively, and control [uncut plants]), associated or not with the removal or burning of resulting plant residues, were evaluated in an area previously used as pasture in 1999/2000 and 2001/2002. Compared to control, the treatments resulted in delays during the harvest window of pure germinable seeds. The accumulation of biomass consisting of leaf remnants and dead or sterile tillers and their segments reduces the production of pure germinable seeds in common U. humidicola. The effect of the type of elimination of this accumulated material depends on the amount accumulated. However, in the two years of the experiment, cutting the plants at 5 cm above ground level at the beginning of the rainy season, followed by removal of these plant residues, increased the production of pure germinable seeds.