Productive potential for dry matter and crude protein in Jiggs Bermuda grass under nitrogen fertilisation

Abstract

The adjustment of nitrogen fertilization is essential to promoting dry matter production together with a high concentration of crude protein in Jiggs Bermuda grass under a continuous cuts. The aim of this study was to quantify dry matter and crude protein production in Jiggs Bermuda grass, a cultivar of the genus Cynodon, associated with nitrogen fertilisation. The experimental design was randomised blocks with four replications, where treatments consisted in five doses of nitrogen (0, 50, 100, 150 and 200 kg ha-1 cut-1) as urea, first applied during seedlings settlement, and second between 5 to 15 days after each harvest. For three years, in the flowering stage of the plants, 0.50 m2 area per plot was collected, totaling 18 collections for the determination of the dry mass, after oven drying at 65 °C until constant weight, and after grinding, the concentration and the crude protein content were quantified. Data were analyzed by variance, adjusting the regressions in function of the levels of nitrogen applied. There was a significant response to the nitrogen dosesin dry matter production and crude protein content. The maximum potential for crude protein content was 158.5 kg nitrogen ha-1 (477.7 kg ha-1 of crude protein content), applied per harvest during the autumn/winter period, and 171.2 kg ha-1 (753.1 kg ha-1 of crude protein content) in the spring/summer, with respective increases of 49.7 and 78.9% regarding to the treatment without nitrogen fertilisation.