Características agronômicas, composição químico-bromatológica e curva de desidratação da Gliricídia sepium

Abstract

The study was conducted in order to evaluate the agronomic characteristics, chemical composition and dehydration curve Gliricídia sepium grown under different residues were in relation to the seasons. The experiment was carried out in the Forage Industry Department of Animal Science of the Federal University of Ceará - UFC in Fortaleza, Brazil. The statistical design was a randomized block design with split plots. Plots consisted of three residual heights (70, 90 and 110 cm) and five 4 seasons (fall, winter, spring and summer) with four replications. For dehydration curve used the design in randomized blocks in a factorial 3x7 factorial comprising the three residues were and 7 times (0, 1, 2, 3, 4, 6 and 8 h) sample collection gliricídia. Growth variables analyzed were: the diameter of the stem at ground level, number of budding, diameter of shoots and plant height. The chemical composition of the plant variables analyzed were: dry matter, ash, crude protein, ether extract, neutral detergent fiber and acid detergent fiber. The growth and composition data were subjected to analysis of variance, the dehydration curve underwent regression analysis. Data were analyzed by program SAS version 9.0 and compared by Tukey test at 5% probability. Agronomic characteristics of gliricidia were influenced by harvest time. Significant differences from the residual height (p˂0,05) were observed on plant growth, stem diameter and diameter of the shoots, leaf area index, fresh weight of the total forage dry matter and total forage. The time of greater plant (p˂0,05) growth was recorded in the winter solstice (June). The diameters of the stem and the shoots grew better on the spring equinox, with measures of 6.85 and 2.07 mm, respectively. While the highest number of shoots was observed in the autumn equinox, with 31, 33 shoots. The dry matter, ash, acid detergent fiber and ether extract, were higher (P˂0.05) at the spring equinox (September 2013), summer solstice (December 2013), Winter Solstice (June 2013) and spring equinox (September 2013), respectively. There was a significant interaction between time of cutting and residual height for fiber neutral detergent, crude protein and organic matter. The highest average values of NDF were recorded at the spring equinox and summer solstice, the higher CP values were recorded in spring and autumn equinox and the largest values organic matter focused on the spring equinox. Effect was observed (P˂ 0,05) in the dehydration time on the dry matter and crude protein of Gliricidia in different residues were. The plants were cut at 90 and 110 cm were 80% dry matter in 6.75 and 6.63 hours of sun exposure. With 8 hours of dehydration was observed values of CP 20.16; 20.00; and 20.80% for waste heights of 70, 90 and 110 cm respectively, and observed losses in the PB values around 3.56; 2.84 and 3.69% for residual heights of 70, 90 and 110 cm, respectively. Gliricidia sepium can be cut in the residual height of 70 cm. The time indicated for the greatest dry matter production, plant growth and chemical composition suitable for animal feed is the winter solstice (June). The dehydration process of Gliricidia sepium occurred in 8 hours of sun exposure, with getting the hay with 80% dry matter and 20% crude protein.