Formas de aplicação do fósforo em um latossolo de cerrado na cultura da soja

Abstract

The dynamics of phosphorus (P) in soil is highly complex in view of the low mobility of this nutrient and its reactions with soil. In order to understand the interactions occurring between phosphorus, soil and plants, has developed this study objective to evaluate the efficiency of application methods, combining the application of phosphorus broadcast with applied in the row-and. For this, an experiment was set up in Randomized Block Designs, with 6 treatments and 4 repetitions in an agricultural area of the first year of cultivation. The treatments were applied on a combined dose of 120 kg ha-1 P2O5 in soybean, 100% broadcast, 75% broadcast and 25% row-and, 50% braadcast and 50% row-and; 25 broadcast and 75% row-and, 100% row-and and control. We evaluated the soybean productivity, plant height and phosphorus content in the leaf. Was evaluated by means of Mehlich-1 and resin, the behavior of phosphorus in the soil outline, its vertical and horizontal mobility. In the assessments of productivity, plant height and P content in leaf, it was noticed statistically superiority of treatments where you have 50, 75 and 100% of the P applied in the row-and. In evaluating the phosphorus present in the soil outline at surface layer of 0 - 2.5 cm, it was noticed that most of the treatments with fertilizer broadcasted (100 and 75%) were significantly higher, and in surface layer 5 to 7.5 cm treatments with most of the fertilizer in the row-and (100 and 75%) are shown above. In avaluation the vertical and horizontal mobility of P in soil, it was noticed that there was no movement of this nutrient in the soil, remaining at the site of application. The results presented by extractants, Mehlich-1 and resin, followed the same trends, and the extraction resin was more stable and is consistent with the treatment.