EFFECTS OF DEFOLIATION AND NITROGEN UPTAKE ON FORAGE NUTRITIVE VALUES OF PENNISETUM SP Authors: M. P. Palacios-Díaz, V. Mendoza-Grimón, J. R. Fernández-Vera, J. M. Hernández-Moreno Journal: Journal of Animal and Plant Sciences (JAPS) ISSN: 1018-7081 (Print), 2309-8694 (Online) Volume: 23 Issue: 2 Pages: 566-574 Year: 2013 DOI: NA URL: https://doi.org/NA Publisher: Pakistan Agricultural Scientists Forum Abstract:

In semiarid regions, the increasing cost of imported forage is encouraging its replacement by on-farm produced fodder crops. The aim of this study was to characterize the nutritive values of maralfalfa grass ( Pennisetum sp.) in function of different harvest frequencies under subsurface drip irrigation. During 2009 a maralfalfa grass experiment was conducted 2 in a field of 8000 m on allophanic soils in the island of Hierro (Canary Islands), under subtropical climate. In a randomized block design, one linear meter from three different rows was sampled of plants from 30 to 120 days. In a 50 2 m subplot, biodegraded liquid pig manure was applied. Crude Protein (CP) in plants was determined with and without it. Another objective was to calculate N uptake which was added by manure and, the N depletion in soil in organic farming production. The results showed that the optimum age for harvesting was 55-60 days and also allowed to obtain relationships between CP and the age of the plant. Our results demonstrate that, in order to obtain high yields of -1 -1 maralfalfa by organic farming, the maximum animal residue use of 240 kg N ha year recommended by the European Community Directive 91/676/EEC should be increased. alternative to increase forage availability for livestock

Keywords: crude protein, drip irrigation, Maralfafa ( Pennisetum sp) , N uptake, N depletion, organic farming