Improving tomato fruit quality by raising the EC of NFT nutrient solutions and calcium spraying: Effects on growth, photosynthesis, yield and quality

Tomato cv. Trust plants were grown with Nutrient Film Technique (NFT). The electrical conductivity (EC) of the nutrient solution was increased to 40 or 80% above the standard, with either all major macronutrients, NaCl or NaCl/KCl following a seasonal EC schedule, in which target EC changed with plant age and ambient solar radiation. Plants were sprayed with 0.1 M CaCl2 or distilled water, biweekly. Calcium spraying reduced the incidence of blossom-end rot (BER) only in early fruit production. Calcium spraying decreased total marketable yield. It appears that calcium spraying should be used only early in the season when solar radiation is not high. Increased salinity reduced total marketable yield and fruit size, but improved tomato fruit. quality. Raising EC 40% above standard improved tomato fruit quality without yield loss, It appears that raising the EC of NFT nutrient solution 40% above the standard (total EC 3.0-4.6 mS cm(-1)) with NaCl is a practical way to improve tomato fruit quality in southwestern Ontario, one of the most important greenhouse vegetable production areas in the world.