Monitoramento das concentrações de nitrato e potássio para o manejo da fertirrigação na cultura do pimentão utilizando medidores de íons da solução.

Abstract

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.