The plants were fertilise with a commercial mixture ( l-0.3-1.44) plus micro-elements.
Electric conductivity and pH of the irrigation water were 1.4 (mS cm-‘) and 6.3, respectively. Before each fertigation, the pots were drained with water for 5 min to avoid accumulation of salts in the substrate. Hence, the substrate conductivity was maintained between 1 and 1.5 mS cm-‘.