Dry matter and nutrients accumulation in Gliricidia sepium in response to water stress and phosphorus levels

Among the factors that have limited plant growth and crop production in tropical regions are the low availability of phosphorus and water stress. These factures assume even greater proportion in the semiarid region of northeastern Brazil. As a result, we conducted an experiment to evaluate the effects of phosphorus and two water regimes effects in dry matter and nutrients accumulation in Gliricidia sepium plants. The experimental design was a randomized block design, arranged in a 2 x 4 factorial scheme, corresponding to two water regimes (with and without water stress) and four phosphorus levels (0; 50; 100 and 150 mg dm(-3) of P). The plants grown in plastic pots containing 9 kg of soil, and the water stress was imposed by the suspension of irrigation, 45 days after emergence and remained in that condition for 15 days. It were analyzed the dry matter and N, P, K, Ca, Mg, S, Fe, Mn, Cu and Zn content in shoots. Water stress was detrimental to the production of dry matter and N and Zn accumulation, while promoted accumulation of P, S and Cu. The fertilization favored N, P, Ca, S, Mn, and Fe shoot accumulation.