ABSTRACT
Introducción: En la región Caribe de Colombia hay presencia de especies nativas de gramíneas que aún no han sido evaluadas. Objetivo: Identificar taxonómicamente una gramínea de la región Sabanas de Sucre y estudiar la influencia de la edad sobre sus atributos morfológicos y de producción. Materiales y métodos: El estudio se ubicó en 9º12'38.59" N y 75º24'06.63", a 165 msnm. En 18 parcelas se evaluaron tres intervalos de corte (21, 28 y 35 días). Inicialmente, se identificó la gramínea. Fue evaluada la composición química, el número y longitud de las hojas, las relaciones entre material verde y seco y entre hojas y tallos, y su evolución, y la producción y tasa de acúmulo de MS. Resultados: La gramínea se identificó como Panicum cf. hispidifolium Swallen. El contenido de PB, NDT y cenizas disminuyeron (P<0,05) con el incremento en la edad, presentando valores medios de 12,3; 58,5 y 9,7%, respectivamente. Las fracciones MS, FDA y CNE aumentaron (P<0,05) con la edad, presentando valores medios de 21,6; 37,17 y 6,24%, respectivamente. La disponibilidad de MS y la tasa de acúmulo evolucionaron cuadráticamente (P<0,05), con mayor intensidad entre los días 21 y 28. El promedio de MS disponible fue de 8049,1 kg/ha y la tasa diaria de acúmulo fue de 281,2 kg/ha. Conclusión: Se concluye que P. hispidifolium es una gramínea con potencial forrajero para la región Sabanas de Sucre, y que se debe manejar con periodos de descanso de alrededor de 28 días, considerando la disponibilidad y calidad de la MS.
Introduction: In the Caribbean region of Colombia there are native species of grasses that have not yet been evaluated. Objective: To identify taxonomically a grass observed in the Savannas de Sucre region and study the influence of age on its morphological and production attributes. Materials and Methods: The study was located at 9º12'38.59"N and 75º24'06.63", at 165 meters above sea level. In 18 plots, three cut intervals were evaluated (21, 28 and 35 days). Initially, the grass was identified. The chemical composition, the number and length of the leaves, the relationships between green and dry material and between leaves and stems, and their evolution, and the production and accumulation rate of DM were tested. Results: The grass was identified as Panicum cf. hispidifolium Swallen. The content of PB, NDT and ash decreased (P <0.05) with increasing age, presenting mean values of 12.27; 58.5 and 9.7%, respectively. The MS, FDA and CNE fractions increased (P <0.05) with age, presenting mean values of 21.6; 37.17 and 6.24%, respectively. DM availability and accumulation rate evolved quadratically (P <0.05), with greater intensity between days 21 and 28. The average DM available was 8049.1 kg / ha and the daily accumulation rate was 281.2 kg / ha. Conclusion: It is concluded that P. hispidifolium is a grass with forage potential for the Savannas of Sucre region, and that it should be managed with rest periods of around 28 days, considering the availability and quality of the DM.
Subject(s)
Panicum , Colombia , VernoniaABSTRACT
O sucesso na utilização de pastagens em sistemas silvipastoris depende da compreensão dos mecanismos morfofisiológicos e de sua interação com o ambiente e do manejo. Objetivou-se avaliar as taxas de aparecimento de folhas (TApF) e alongamento de folhas (TAlF) e colmos (TAlC), número de folhas emergentes (NFEm), expandidas (NFEx) e vivas (NFV), cobertura do solo e altura do capim-marandu consorciado com coco-anão. O experimento foi conduzido em esquema de parcelas subdivididas, tendo nas parcelas os tratamentos irrigado e não-irrigado e nas subparcelas seis intervalos de desfolha (14, 21, 28, 35, 42 e 49 dias), no delineamento inteiramente casualizado com seis repetições. A irrigação proporcionou aumento na cobertura, altura e na TAlF e TAlC do capim-marandu para os intervalos de desfolha de 49 e 14 dias, respectivamente. O intervalo de desfolha proporcionou redução linear nas TApF e TAlC, e aumento linear no NFEx, NFV, cobertura e altura do capim-marandu. A TAlF é maior quando se utilizam intervalos de desfolha de 37 e 29 dias, para o capim-marandu irrigado e não-irrigado, respectivamente. Conclui-se que mesmo em condições de sombreamento, o capim-marandu, quando irrigado e submetido a maiores intervalos de desfolha, proporciona maiores taxas morfogênicos e de crescimento, indicando o potencial desta forragem em sistemas integrados de produção.
The success in the use of pastures in silvopastoral systems depends on the understanding of the morphophysiological mechanisms and its interaction with the environment and of the management. It was aimed to evaluate the leaf appearance rate (LAR), leaf elongation rate (LER), stem elongation rate (SER), emerging leaf numbers (EmLN), expanded leaf numbers (ExLN), living leaf numbers (LLN), soil cover and plant height of Marandu grass intercropped with coconut. The experiment was mounted in a completely randomized arrangement, with six replications, in a split-plot design. The plots a treatments irrigated and not-irrigated and six rest periods in the split-plots (14, 21, 28, 35, 42 and 49 days). The irrigation provided increase in the soil cover, plant height, LER and SER of Marandu grass for the rest periods of 49 and 14 days, respectively. The rest periods provided linear reduction in the LAR and SER, and linear increase in the ExLN, LLN, soil cover and plant height of Marandu grass. The LER is bigger when rest periods used of 37 and 29 days, for Marandu grass irrigated and not-irrigated, respectively. It concludes that exactly in shade conditions, Marandu grass, when irrigated and submitted the biggest rest periods, provides to greaters morphogenic taxes and growth, indicating the potential of this fodder plant in integrated systems of production.