Silva Marcos F, Porto Edson M V, Alves Dorismar D, Vitor Cláudio M T, Aspiazú Ignacio
Departamento de Ciências Agrárias, Universidade Estadual de Montes Claros (UNIMONTES), Avenida Reinaldo Viana, 2630, Bairro Bico da Pedra, 39440-000 Janaúba MG, Brasil.
An Acad Bras Cienc. 2013 Mar;85(1):371-7. doi: 10.1590/s0001-37652013005000004. Epub 2013 Mar 1.
This study aims to evaluate the morphogenetic characteristics of three cultivars of Brachiaria brizantha subjected to nitrogen fertilization. The design was a randomized block in factorial arrangement 4x3; three cultivars of B. brizantha - Marandu, Piatã, Xaraés and four nitrogen levels - 0, 80, 160 and 240 kg/ha, with three replications. The experimental units consisted of plastic pots filled with 5 dm3 of soil. Thereupon the establishment fertilization, varieties were sowed directly in the pots, leaving, after thinning, five plants per pot. Forty-five days after planting, it was done a standardization cut at 10 cm tall. Nitrogen levels were distributed according to the treatments, divided in three applications. The morphogenetic characteristics were evaluated in three tillers per sampling unit and data were submitted to analysis of variance and regression. For all evaluated characteristics there was no interaction between factors cultivar and nitrogen levels, verifying only the effects of nitrogen on the variables leaf appearance rate and phyllochron. The dose 240 kg/ha of N corresponds to the greater leaf appearance rate. Cultivar Marandu shows the higher leaf blade: pseudostem and ratio of leaf elongation rate and elongation pseudostem, which favors higher forage quality.
本研究旨在评估施氮肥条件下三种臂形草品种的形态发生特征。试验设计为4×3析因排列的随机区组设计；三种臂形草品种——马兰杜、皮亚塔、沙拉埃斯，以及四个氮水平——0、80、160和240千克/公顷，重复三次。试验单元由装有5立方分米土壤的塑料盆组成。随后进行基肥施用，将品种直接播于盆中，间苗后每盆留五株。种植45天后，在10厘米高处进行标准化刈割。氮水平根据处理进行分配，分三次施用。在每个采样单元的三个分蘖上评估形态发生特征，并将数据进行方差分析和回归分析。对于所有评估特征，品种和氮水平之间不存在交互作用，仅验证了氮对叶片出现速率和叶龄期变量的影响。2
