Tree legumes are a viable option to increase ecosystem services provided by warm‐climate grasslands. Benefits of using tree legumes in silvopasture systems (SPS) include the provision of shade for livestock, biological N2 fixation, and C sequestration. This study assessed cattle performance and pasture characteristics in signalgrass (Brachiaria decumbens Stapf.) pastures in monoculture or in SPS. The following treatments were assessed: (i) signalgrass/sabiá (Mimosa caesalpiniifolia Benth.), (ii) signalgrass/gliricidia [Gliricidia sepium (Jacq.) Kunth ex Walp.], and (iii) signalgrass monoculture. Crossbred steers were managed under continuous stocking and variable stocking rates. Response variables included herbage mass, herbage allowance, stocking rate, average daily gain (ADG), gain per area (GPA), in vitro dry matter digestibility (IVDMD), and crude protein (CP). Total signalgrass herbage mass in monoculture (5091 kg DM ha−1) was greater (P ≤ 0.05) compared with SPS (3964 kg DM ha−1). Green signalgrass herbage mass, however, was greater (P ≤ 0.05) for SPS (2237 kg DM ha−1) compared with monoculture (1934 kg DM ha−1). Herbage allowance, IVDMD, CP, stocking rate, ADG, and GPA did not differ among treatments, with average values of 2.9 kg−1 green herbage mass (DM) kg−1 live weight; 633 g kg−1, 55 g kg−1, 1.9 animal units (AU) ha−1 (1 AU = 450 kg live weight); 0.57 kg−1 AU−1 d−1; and 30 kg ha−1 28 d−1, respectively. During the establishment phase (3 yr), SPS with tree legumes can produce as much livestock gain as signalgrass in monoculture, providing other ecosystem services and marketable products, increasing land use efficiency.Core Ideas Livestock production was similar in silvopasture systems and signalgrass monoculture. Silvopasture systems provided additional ecosystem services compared with grass monoculture. The use of tree legumes adds biologically fixed N2 and provide other ecosystem services. Trees compete with herbaceous vegetation and might reduce livestock production in the long term.

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O objetivo deste trabalho foi avaliar dietas a base de palma forrageira (aproximadamente 54 %) associada a diferentes fontes de fibra sobre o consumo, digestibilidade, comportamento alimentar e balanço de nitrogênio de cinco ovinos machos, com peso inicial entre 34kg. As fontes de fibra avaliadas foram: feno de tifton, casca de soja, caroço de algodão, feno de tifton + casca de soja e feno de tifton + caroço de algodão. Utilizou-se o delineamento quadrado latino 5x5. Não houve diferença para o consumo de matéria seca, matéria orgânica, proteína bruta, fibra em detergente neutro e nutrientes digestíveis totais. A palma associada ao caroço de algodão apresentou maior coeficiente de digestibilidade de extrato etéreo. Os coeficientes de digestibilidade da matéria seca e fibra em detergente neutro do tratamento com casca de soja foram superiores ao feno de tifton + caroço de algodão.O tratamentofeno de tiftonefeno de tifton+casca de sojaapresentaram maiordigestibilidade da proteína brutaem relação aocaroço dealgodão.O tratamento com palma associada à casca de soja apresentou média de excreção de nitrogênio nas fezes superior aos demais. O maior valor de excreção de nitrogênio na urina correspondeu ao tratamento feno de tifton + o caroço de algodão. A palma associada à casca de soja proporcionou menor tempo em ruminação e mastigação total. É recomendado o uso da palma forrageira associada com feno de capim tifton e casca de soja como fontes de fibra na alimentação de ovinos.

This study investigated whether genotype influences the establishment of Pennisetum purpureum Schumach. The experimental design was a randomized complete blocks with four treatments and eight replications (n=8). The treatments were four genotypes of P. purpureum, two classified as tall sizes: P. purpureum cv. Elephant B and cv. IRI 381; and two as dwarf types: P. purpureum cv. Mott and Taiwan A-146 2.37. They were planted in a tropical wet and dry region of Brazil. Tall genotypes showed superior field sprouting rates (p < 0.05), ranging between 95-99%, while dwarfs varied between 88-90%, however, Elephant B and IRI 381 produced a much lower average number of tillers (31 and 32 linear m-1, respectively), than Taiwan A-146 2.37 and Mott (56 and 41 linear m-1, respectively) (p < 0.05). Dwarf genotypes produced lower biomass yields (p < 0.05), but this was genotype-dependent and did not impact on their establishment. The levels of non-structural carbohydrates (NSC) (>10%) in the planted stems were associated with satisfactory field sprouting of the elephantgrass genotypes. Despite some variations between the genotypes in terms of sprouting, tillering, and growth rates, the kind of genotype had no major significance on the establishment of the elephantgrass.

This study hypothesised that different elephant grass genotypes respond differently in terms of their morphological development to irrigation. The objective of this study was to evaluate how water availability could affect the morphological development of different genotypes of elephant grass. The treatments consisted of four genotypes of elephant grass [Cenchrus purpureus (Schumach.) Morrone], managed under irrigation or not, during a two‐year field trial. The experiment was arranged in a randomised block design in a split‐plot, with four replicates per treatment (n = 4). Between the genotypes, two of them were classified as tall‐sized (IRI 381 and Elephant B), and two as dwarfs (Taiwan A‐146 2.37 and Mott). A three‐way interaction between season, irrigation, and genotype affected the variables plant height, stem diameter, number of dead tillers, light interception (LI), and leaf area index (LAI) (p < .05). The morphological development of all genotypes was negatively impacted by the dry season. All genotypes grew taller during the rainy season (p < .05) and had a greater light interception (62%–80%) compared to the dry period (28%–59%). The genotype Mott, showed comparable LI and LAI to the tall‐sized genotypes, whilst Taiwan A‐146 2.37 was characterized by the lowest values, despite being the genotype with the greatest tiller density (60 tillers m−2) (p < .05). The use of irrigation mitigated the negative effects of the dry season on the plants, however, the type and size (tall vs. dwarf) of the elephant grass genotypes defined the extent of the responses to the use of the irrigation during the dry period.