Pesquisa Agropecuária Brasileira
versión impresa ISSN 0100-204X
VIANA, Bruno Leal et al. Repeatability of morphophysiological and yield characteristics and response of dwarf elephant grass under grazing. Pesq. agropec. bras. [online]. 2009, vol.44, n.12, pp. 1731-1738. ISSN 0100-204X. http://dx.doi.org/10.1590/S0100-204X2009001200024.
The objective of this study was to estimate the coefficients of repeatability and determination (R2) and the minimum number of measurements necessary to predict the real value of morphophysiological and yield variables, as well as the responses to sheep-grazing of dwarf elephant grass pasture. The experiment was carried out in a randomized block design with five treatments - Taiwan A-146 2.27, Taiwan A-146 2.37, Taiwan A-146 2.114, Merker México MX 6.31 and Mott - and four replicates, over five grazing cycles, between September 2008 and April 2009. Mean sward height, leaf area index (LAI), light interception (LI), mean leaf angles (MLA), silage accumulation (SA) and silage accumulation rate (SAR) were evaluated. For the variables LAI, IL and mean sward height of plants, in long cycles, only one measurement was necessary (R2 = 80%) to place them among the most predictable characteristics in the evaluation of elephant grass clones. Assessments for SA and SAR need longer experimental periods for greater reliability in the estimation of response variables. In dwarf elephant grass, light interception increases with sward height and LAI.
Palabras llave : Pennisetum purpureum; leaf angle; dwarf elephant grass; leaf area index; light interception.