Schoninger, E.L. Gatiboni, L.C. Ernani, P.R. Rhizosphere pH and phosphorus forms in an oxisol cultivated with soybean, brachiaria grass, millet and sorghum Subjects--Topical Terms: RHIZOBIUMFÓSFOROFERTILIDADE DO SOLOOXISOLPHSOJAMILHOSORGOCAPIM BRACHIARIA