Revista Brasileira de Zootecnia
On-line version ISSN 1806-9290
DIFANTE, Gelson dos Santos et al. Morphogenetic and structural characteristics of marandu palisadegrass subjected to combinations of cutting heights and cutting intervals. R. Bras. Zootec. [online]. 2011, vol.40, n.5, pp. 955-963. ISSN 1806-9290. http://dx.doi.org/10.1590/S1516-35982011000500003.
The objective of this study was to evaluate forage accumulation and morphogenetic and structural characteristics of marandu palisadegrass subjected to combinations of cutting heights and cutting intervals. The experiment was carried out from August 2003 to April 2004. Treatments corresponded to combinations between two cutting heights (15 and 30 cm) and three cutting intervals (time corresponding to the appearance of three, four and five new leaves per tiller), and they were allocated to experimental units according to a 2 × 3 factorial arrangement and a complete randomised block design, with three replications. It was evaluated accumulation of total forage, leaf blade, stem and dead material, morphogenetic and structural variables, as well as, pre-cut sward height and regrowth duration. Swards cut at 15 cm had shorter regrowth periods, pre-cut sward height, stem elongation rate and final leaf size, and larger tiller population density than swards cut at 30 cm. The cutting interval corresponding to the appearance of five leaves per tiller resulted in higher pre-cut sward height, leaf elongation rate, final leaf size, stem accumulation and smaller tiller population density than those intervals corresponding to three and four leaves per tiller. The greatest utilization efficiency of marandu palisadegrass pastures was achieved with cuts at 15 cm. Pastures managed with cutting intervals corresponding to three new leaves per tiller regardless of cutting height evaluated, accumulated high quantities of leaf, a highly desirable component for animal feeding purposes.
Keywords : Brachiaria brizantha; ecophysiology; forage production; leaf appearance; leaf elongation; sward height.