CRESCIMENTO INICIAL, N˝VEIS CR˝TICOS DE F"SFORO E FRA˙'ES FOSFATADAS EM ESP…CIES FLORESTAIS 1

An experiment under greenhouse conditions was carried out at Universidade Federal de Lavras, Minas Gerais State, Brazil, to evaluate the growth of seedlings, phosphorus critical levels and phosphate fractions, in forest species growing under four phosphorus levels. Seedlings of Schinus terenbinthifolius Raddi (aroeirinha), Chorisia speciosa St. Hill. (paineira) and Syzygium jambolanum Lam. (jambolao) were cultivated on an Oxisol fertilized with 0, 150, 300 and 600†mg†dm -3 of P. The seedlings were harvested 180†days after germination and analysed for P forms. In all levels of phospho- rus addition, the paineira produced higher aerial and root biomass than aroeirinha and jambolao, and presented higher contents of organic phosphorus and higher relative participation of organic phospho- rus in the total acid soluble phosphorus under all phosphorus levels. The improved growth rate of paineira was attributed to a greater efficiency in the metabolic adjustments of this species in relation to phosphorus nutrition, indicating that this species can grow in soils of variable P levels.