Abstract

CERDAS-RAMIREZ, Roberto. Productive behavior of maralfalfa grass with various levels of nitrogen fertilizer. InterSedes [online]. 2015, vol.16, n.33, pp.124-145. ISSN 2215-2458.

A study was conducted to evaluate the performance of Maralfalfa grass in Santa Cruz, Guanacaste, located 54 masl and with an annual rainfall of 1834 mm. The production of green and dry biomass, production of metabolizing energy and raw protein per hectare, chlorophyll content, extraction of macro and micronutrients of grass subjected to four nitrogen dosages per cut of 49 days were evaluated: 0, 30, 60 and 90 kgN.ha^-1. The yield of dry biomass varied with the dosage of N applied: 1760, 5193, 9820 and 12157 kgDM.ha^-1.cut-1. The production of metabolizing energy per hectare varied when fertilized with increasing nitrogen levels: 3847, 10982, 25142 and 26571 Mcal ME.ha^-1.cut-1 as well as for raw protein: 156, 541, 1334 and 1976 kgCP.ha^-1.cut-1, with 0, 30, 60 and 90 kgN.ha^-1.cut-1. Chlorophyll content (SPAD) increased with the dose of nitrogen applied: 27.9, 33.1, 37.1 and 40.4 SPAD units. All nutrients are presented in suitable animal production quantities; however, potassium values exceeded toxic levels. Quadratic prediction equations were calculated. It is recommendable to apply 80 kgN.ha^-1 by cut of 49 days.

Keywords : Maralfalfa; nitrogen fertilization; energy and protein per hectare; chlorophyll (SPAD); extraction of micro and macronutrients.

        · abstract in Portuguese     · text in Spanish     · Spanish ( pdf )