João Vitor de Souza Silva
Abstract:
The application of phosphate fertilizer is indispensable to obtain sustainable bean production, being P the necessary nutrient practically throughout its cycle. Thus, cultural management alternatives are being used aiming at the best use of this nutrient, among them the use of brachiaria as a cover plant. The objective of this research was to evaluate the dynamics of phosphorus in the soil with and without the presence of Brachiaria brizantha cv. Marandú as a cover plant, as well as bean response to phosphate fertilization in these two systems. The experiment was carried out in a dystroferric red latosol at the Federal University of Goiás, Jataí Regional-GO, where a randomized complete block design (DBC) was used, in a split plot arrangement, and the plots were composed of P2O5 doses. (0, 50, 100, 200 and 400 kg ha-1), and the subplots were composed by the presence and absence of brachiaria as a cover plant prior to bean cultivation. For fertilizer distribution was used furrower containing 4 traction rods, where the furrows were made approximately 7 cm from the soil and the fertilizer placed manually. Bean sowing occurred after phosphate fertilization, using a pneumatic seeder with 7 individual rows spaced 0.50 m, placing 10 seeds per meter. Soil samples were collected in 3 seasons, as follows: 1) 15 days after bean sowing (15DAS); 2) 30 days after bean sowing (30DAS) and 3) postharvest of bean (PC). In the collected samples, the phosphorus was fractionated in the soil by the Hedley technique. In bean plants were evaluated plant height, number of pods per plant, leaf phosphorus content, plant dry mass, 100 grain mass and yield. The treatments, P2O5 doses and presence of Brachiaria brizantha cv. Marandú as cover plant, provide changes in soil P-labile content at 15 and 30DAS of bean, and soil P-placable at 15 DAS of bean. The presence of Brachiaria brizantha cv. Marandú as cover crop increased the phosphorus content of the bean leaf, resulting in increased productivity.
