DUARTE, S. N.; TAVARES, A. C. S.
Résumé:
The handling should be adapted them circumstance doesn't tend rule fastens. The
treatments were composed of the combination of 4 levels of N (N1 = 200, N2 = 300, N3 = 400 kg
have-1 of N, N4 = maintenance of the concentration of NO3 - in the solution of the substratum among
7 to 15 mmolc
L-1) and 4 levels of K (K1 = 450, K2 = 550, K3 = 650 kg have-1 of K2O, K4 =
maintenance of the concentration of K+
in the solution of the substratum among 3 to 4 mmolc
L-1), in a
total of 8 levels. The objective of that work was it of handling the fertirrigation for the treatments N4
and K4, with the maintenance of the concentrations of NO3
-
and K+
, close the averages of 682 and
136,5 mg L-1, respectively. The experiment was driven Department of Rural Engineering of the
Escola Superior de Agricultura "Luiz of Queiroz" - USP, in the municipal district of Piracicaba-SP.
The experiment was driven in a plastic greenhouse. The used substratum was Golden-Mix. The
nutrients containing N and K were dissolved previously in solutions stock. The handling of the
fertirrigation using ions meters in the monitor of the concentrations of nitrate and potassium came
effective, obtaining doses of similar fertilizers the smallest levels N1 and N2 for the nitrogen and an
economy around 85% in relation to smaller potassium levels.
