2017-11-242017-11-242001-12KLIEMANN, Huberto José; LIMA, David Vieira. Eficiência agronômica de fosfatos naturais e sua influência no fósforo disponível em dois solos de cerrado. Pesquisa Agropecuária Tropical, Goiânia, v. 31, n. 2, p. 111-119, jul./dez. 2001. Disponível em: <https://www.revistas.ufg.br/pat/article/view/2472>.1517-6398http://repositorio.bc.ufg.br/handle/ri/12989To evaluate the agronomic efficiency of natural phosphates soybean was grown in two oxisols under cerrado vegetation, using apatites (Araxá, Patos de Minas, Tapira, Abaeté, and Catalão), phosphoric bauxites (Pirocaua and Phospal), Gafsa hyperphosphate, and IPT thermophosphate, using triple superphosphate as a control. The agronomic efficiency indexes found were: a) apatites - Araxá and Abaeté, 27%; Patos de Minas, 13%; Tapira, 5%, and Catalão, 2%; b) phosphoric bauxites - Pirocaua, 41% and Phospal, 50%; c) thermophosphate IPT, 97% and hyperphosphate of Gafsa, 102%. The acid extractor Mehclich-1 overestimates available P when insoluble apatites are applied to soils. Bray-1 and Bray-2 extractors preferably solubilize the aluminum phosphates from phosphoric bauxites. Critical levels of soil available phosphorus are suitably estimated by Bray-1 extractant when apatitic phosphates and by Mehlich-1 extractant phosphoric bauxites are applied.porAcesso AbertoLatossolosCerradosSojaFontes de fósforoExtratores químicosOxisolsSoybeansPhosphates sourcesChemical extractorsSoybeanArtigo