ABSORÇÃO DE NUTRIENTES E SÓDIO PELO CAUPI EM SOLOS SALINO-SÓDICOS CORRIGIDOS COM GESSO

Abstract

The use of mine gypsum in reclamation of soils with high levels of exchangeable sodium is viable by its effectiveness, and although this product show others advantages as low price and easy applicability in field. The product is finding in great amount at the Araripe Highland, located across (between) the division of the Ceará and Pernambuco states. The aim of the research work is to evaluate the shoot dry biomass and Ca+2, Mg+2, K+, P and Na+ accumulation on cowpea plants grown in two saline sodic soils recently amended with gypsum. The experiment was carried out in a completely randomized factorial design with three replications, applying 6 levels of gypsum in two soils. The statistical calculations were achieved using the Program SAEG 9.0 and the standard deviations and the averages were compared by the Tukey test at probability P < 0.05. The effects of gypsum levels and the relationships between the variables were analyzed by the Pearson correlation test. Application of gypsum in different levels reduced sodium uptake and increased shoot dry biomass of cowpea plants grown in the Neossolo Flúvico Eutrófico Saline Sodic soil with medium texture. Higher levels of gypsum promoted reduction in phosphorus accumulation on cowpea plants grown in the Neossolo Fluvico Eutrófico saline sodic soil with medium texture.