Consórcio de guandu-anão com Urochloa ruziziensis para produção de feno tropical

Abstract

The pastures are the main food source for ruminant animals representing the only diet in many production systems, being in the most economical way of production of meat and milk, although often do not answer in terms of productivity, depending on the low nutritive value of fodder used. In this sense, the consortium between leguminous and grass is beneficial for production systems, because it increases biomass production, promote the biological fixation of atmospheric nitrogen and quality of fodder for animal feed. The aim of this study was evaluate the consortium of pigeonpea and U. ruziziensis for tropical hay production in the cerrado. For this, an experiment was conducted in the experimental area belonging to the Fazenda Santa Brígida, municipality of Ipameri-GO, agricultural season 2012/2013, in the months between November to April. The experimental design was randomized complete blocks with six replicates. To analyze biomass, the experiment was in a split-plot scheme, being distributed kinds of consortia on the plots and the days after emergence (DAE) of the species tested in subplots. The treatments were composed of two species of plants, a pigeonpea (Cajanus cajan) legume and a Urochloa ruziziensis (syn. Brachiaria ruziziensis) grass, in monoculture and intercropping. The treatments were: (i)U. ruziziensis 100% - 8 plants per square meter (ii) pigeonpea 100% - 9 plants per square meter, (iii) 3 pigeonpea per square meter e 8 U. ruziziensis per square meter, (iv) 6 pigeonpea per square meter e 8 U. ruziziensis per square meter, (v) 9 pigeonpea per square meter e 8 U. ruziziensis per square meter, (vi) 12 pigeonpea per square meter e U. ruziziensis per square meter, (vii) 15 pigeonpea per square meter e 8 U. ruziziensis per square meter. The size of the experimental area was 666 per square meter. The plots of pigeonpea in monoculture and under a consortium with U. ruziziensis were constituted of four rows of 5.0 m long, spaced 0.5 cm. Both the consortium system and monoculture, were sampled the two centerlines of each parcel as principal area. The characteristics examined were subjected to analysis of variance, F-test, and the averages of the treatments were compared by Scott-Knott test at 5 of probability, through the SISVAR program. There was need to apply a quadratic transformation to biomass data and regression analysis of the data of green and dry matter mass. The characteristics evaluated were: Green matter mass (GMM), mass of dry matter (MDM), chemical composition and nutrient content of aerial part of U. ruziziensis. The consortium promoted larger increments of green and dry matter mass in different cuts, mainly to 114 DAE, as compared with monoculture. Consortia showed intermediate values for the variables qualitative characteristics (moisture, crude protein, Crude Fiber, Stereo Extract, calcium, phosphorus, NDT in natura and NDT dry matter), with the exception of Mineral Material. The K content presented high concentrations on entire plant of U. ruziziensis in monoculture, as well as the consortia (3 P + 8 UR, 12 P + 8 UR and 15 P + 8 UR). Based on these results, it is necessary to conduct more studies that validate the adoption of different combinations of grasses and legumes, especially with the species of pigeonpea and U.