PHOSPHATE FERTILIZATION EFFICIENCY IN SOYBEAN CULTIVARS INDICATED FOR CERRADO TROPICAL SOIL REGIONS

Abstract

Phosphorus deficiency (P2O5) is among the main abiotic stresses that limit soybean production in cerrado soils. Its low availability in soils, especially in the more weathered and acidic ones, the increased demand and its scarcity estimations leadto the need for the development of cultivars more efficient in the use of this mineral. This experiment was conducted under field conditions in the municipality of Imperatriz, state of Maranhão, Brazil, under planosol conditions, in a randomized complete block design, with treatments arranged in a 2x4 factorial scheme with four replicates, four P levels (0, 60, 120 and 180 kg ha-1), and two soy bean cultivars (BRS 333 RR and BRS 9180 IPRO) indicated for tropical regions or Brazilian cerrado. In this study, P2O5 efficiency use was evaluated based on plant height, shoot dry mass (SDM), pod dry mass (PDM) and number of pods (NP). BRS 333 RR cultivar obtained the highest efficiency with doses of 84.35 kg ha-1 and 94.46 kg.ha-1, producing 696,76.76g e 86,72.06g for SDM and PDM respectively, average height of94.15 cm with 123.98 kh.ha-1 and phosphate fertilizer use efficiency (FUE) of 13%