RESPONSE TO SODIUM CHLORIDE SALINITY AND EXCESS BORON IN GREENHOUSE TOMATO GROWN IN SEMI-CLOSED SUBSTRATE CULTURE IN A MEDITERRANEAN CLIMATE

The effects of sodium chloride (NaCl) salinity and boron (B) toxicity were investigated in greenhouse tomato (Solanum lycopersicum L.) plants grown in closed soilless culture under the typical climatic conditions occurring in the Mediterranean regions. The experiment was conducted under semi-commercial conditions. Two NaCl (2.0 and 10.0 mol m−3) and B (27.8 and 185.0 mmol m−3) concentrations were combined to produce four different types of raw water used to prepare the nutrient solutions. The fertigation treatment did not affect significantly the uptake of water and mineral elements apart from that of sodium (Na), chloride (Cl), and B. The use of B-enriched water increased the accumulation of this element in the leaves, which showed marginal chlorosis and necrosis within 35–40 days from planting. No or minor effects of NaCl and B concentrations in the irrigation water were found on leaf area development, biomass accumulation, crop yield and fruit quality.