ABSTRACT
Phosphorus deficiency is one of the most important yield-limiting factors in bean production in lowland soils of Brazil. A field experiment was conducted for two consecutive years to calibrate a lowland soil analysis (Inceptisol) regarding to phosphorus in the bean ( Phaseolus vulgaris L.) production. In the first year, the broadcast P rates were 0, 200, 400, 600, 800 and 1000kg P2O5.ha-1. In the second year, each broadcast P rate received band application of 0, 50, 100 and 150kg P2O5.ha-1. Interpretation of P levels for Mehlich-l extracted soil and the P fertilization recomendations for the bean crop were based on relative grain yield. Very low soil tests ranged from 0 to 5.3mg P.kg-1, low from 5.3 to 7.1mg P.kg-1, medium from 7.1 to 9mg P.kg-1, and high exceeded 9mg P.kg-1 soil. The amounts of broadcasted P needed to build up soil P concentrations at very low, low, medium, and high soil categories were 350, 560, 760 and more than 760kg P2O5.ha-1, respectively. The amounts of banded fertilizer P required to obtain maximum yield were 150kg P2O5.ha-1 for the very low soil P level, 100kg P2O5.ha-1 for the low and medium soil P levels and 50kg P2O5.ha-1 for the high soil P level.
Key words:
Phaseolus vulgaris; grain yield; soil P concentration; nutrient accumulation