PSXI-36 Productivity of the Mombaça grass cultivated in a crop-livestock-forest integration system in the Amazon region.

摘要

This study aimed to evaluate the effect of shading caused by different orientations of ranks of eucalyptus ( spp.) on the height and dry matter yield (DM) of the Mombaça grass ( ) cultivated in a crop-livestock-forest integration system, during the rainy season. The experiment was conducted at the Federal Institute of Rondônia, Campus Colorado do Oeste-RO, Brazil (13°07’40’’S, 60°29’07’’W, 400m). The eucalyptus ranks were implanted in double rows, spaced 3 x 2m (between rows and between plants, respectively) and 26 m between ranks. When Mombaça grass was sampled, the trees were, on average, 12m high. The experimental design was in randomized blocks, subdivided into plots (2x3) with three replications. The plots consisted of the two orientations planting of ranks (east-west and north-south), and the subplots were three parallel planting ranges between the ranks (ranges 1 and 3: 0 to 8,6m in relation to the ranks; and range 2: 8.7 to 17.3m, located in the central part between the ranks). The statistical model used was: Yijk = μ + Pi + Sij + P*Sij + eijk, where: Yijk - observed value; μ - overall constant; Pi - effect of plot; Sij - effect of splitplot; P*Sij - effect of interaction and eijk - randomized error. There was no isolated effect of planting ranges on the canopy height (P=0.626) and DM productivity (P=0.745). However, the Mombaça grass cultivated in the east-west direction presented higher canopy height (P<0.001) and higher productivity (P=0.001), with values of 0.95m and 2.62t DM.ha , respectively. The cultivation in the north-south direction showed 0.8m height and productivity of 1.25t DM.ha . It is concluded that in a crop-livestock-forest integration system in the Amazon region, ranks of trees planted in the east-west direction allow a higher incidence of luminosity in the canopy of pasture, thus increasing its dry mass productivity.