Phosphorus availability for soybean cropped over brachiaria straw

Abstract

Brazilian soils are deficient in phosphorus, an essential element for plant growth. So it is limiting for crop yields in tropical soils. Conservation systems as no-till modifies P dinamics in soil, increasing its concentration mainly in the superficial soil layers. the inclusion of some plant species in the system can promote P availability and improve its distribution within the soil profile. In this experiment the contribution of brachiaria in making P more available for soybeans as weel as its effect on P forms in the soil. The experiment will be conducted in Botucatu, using rates of Suluble and Natural phosphates applied broadcast or in furrow, with and without cropping to brachiaria. (AU)