DISPONIBILIDADE DE FÓSFORO EM NEOSSOLO QUARTZARÊNICO CULTIVADO COM MELÃO

Abstract

In function of the low availability, due the precipitation and specific adsorption, the phosphorus is very required in fertilization programs. The availability of the phosphorus can be evaluated through chemical extractors, aiming simulate the soil-plant system. The aims of this work are: to determine the available phosphorus in a Quartzarenic Neosol through Mehlich -1, Mehlich -3 and Bray -1 extractors and to observe the relationship between the absorbed and accumulated phosphorus in the melon crop. The experiment was carried out in a greenhouse at Federal Rural University, Pernambuco state, Brazil, in casualizated blocks with three replications and six doses of phosphorus (0, 37, 74, 148, 222 and 370 mg dm-3). The plants were collected at 37 days after seedling, determining the dry mass and the content of phosphorus in the shoot biomass and were collected soil samples to determine available phosphorus with Mehlich - 1, Mehlich - 3 and Bray - 1 extractors. The extractors didn't present differences to the available phosphorus. The increase of soil phosphorus doses increased the phosphorus content in the dry mass, without to cause changes in the production of dry mass.