Produtividade e qualidade de 4 forrageiras em função de doses de nitrogênio

Abstract

Currently, most brazilian pastures have some degradation degree, and conservation practices are needed to improve their conditions, such as adoption of new species and fertilization, especially nitrogen. The aim of this experiment was to evaluate the quantitative and qualitative performance of four forages (Brachiaria brizantha cv. Marandú, Brachiaria decumbens, Brachiaria brizantha cv. Xaraés and Panicum maximum cv. Mombaça) after N doses application (0, 100, 200, 400 kg ha-1). The experiment was carried out at Santo Domingo Farm, located in Taciba county, in which soil type is Typic Dark. The experimental design used was a randomized block, in a 4 x 4 factorial scheme, with four replications. At early 2008 august, forages were sown manually in five rows, spaced m between rows, being conducted from 2009 September to January 2009. On 2008 October, sidedressing nitrogen fertilization was applied (60 days after emergence). The first cut was held on November 23 and the second in January 2009 (42 days after the first cut), being determined shoot dry matter yield (kg ha-1), neutral detergent fiber content and crude protein (CP). Nitrogen fertilization increases shoot dry matter yield, with emphasis on Brachiaria brizantha cv. Xaraés and Panicum maximum cv. Mombaça; Panicum maximum displays, irrespective of sidedressing nitrogen application, higher crude protein values. Brachiaria brizantha cv. Xaraés and Panicum maximum cv. Mombaça had the lowest crude fiber levels.