Saturação por bases e nitrogênio no desenvolvimento do capim-pojuca cultivado em vasos

Abstract

An activity determinam to a good production and quality offorage grass is ascribed to soil fertility management. This work aimed to evaluate the forage of Paspalum atratum Swalen cv. Pojuca in two distinct experiments. The experiments were conducted in greenhouse of the Soil Science Department of the Universidade Federal de Lavras. Sowing was performed in plastic pots without orifices with a capacity of4 dm3 ofsoil. Experiment 1 was conducted in a Yellow-Red Latosol. The treatments consisted offour doses ofN (0, 100, 200 and 400 mg/dm3)and four leveis of base saturation (18, 40, 60 and 80%). Experiment 2 had as treatments four doses of N (0, 100, 200 and 400 mg/dm3) and four leveis ofbase saturation (40, 50, 60 and 80%). In both experiments, the experimental design was in a randomized blocks, constituting for each, a 4 x 4 factorial scheme with four replicates. The morphogenetic characteristics, tiller appearance rate (TAR) , tiller lengthening rate (TLR) and leaf appearance rate (LAR) before the first cutting were evaluated. Also, tiller density (TD), dr>' matter yield (DMY), "in vitro" dry matter (IVDMD), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) , phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) at the three cuttings performed and total dry matter yield (TDMY) ofthe three cuttings were assessed The pojuca-grass presented significam responses to the N treatments in both soils, providing increased yields and forage quality. The increase in the leveis of base saturation provided significam variations in Red-Yellow Latosol in the parameters TAR, TD, DM, CP, Ca and Mg. The interaction among the treatments was significam for DM at the second cutting, TDMY and FVDMD at the second and third cuttings. In Gleysolo Haplic, only the chemical composition of the forage was affected by the increase in the leveis of base saturation . The interaction among the treatments only influenced CP at the second cutting. It follows that the pojuca grass responds to base saturation leveis bellow that recommended for that forage grass as well as the application ofelevated doses in the two soils studied.