Irrigation with salt water affects growth, yield, fruit quality, storability and marker-gene expression in cherry tomato

Abstract

ABSTRACTThe use of saline water for plant production will become increasingly necessary over future decades. In some cases, fruit quality such as in tomato, can be improved by irrigation with saline water. The influence of different salt concentrations on physiological responses and the expression of some selected genes of cherry tomato (Solanum lycopersicum L), cv. West Virginia 106, was examined. Tomato plants were grown in peatmoss substrate and irrigated with 0, 25, 50, 75, 100 or 150 mM sodium chloride (NaCl) in a glasshouse. The NaCl treatments of 75, 100 and 150 mM salt resulted in shorter plants, decreased stem width, a lower plant dry weight, fewer flowers, and smaller leaf area, while yield was reduced by treatment with concentrations of 50 mM NaCl and above. Average fruit weight and fruit number were also negatively affected by treatment with 50 mM salt and above. Salinity treatment led to increased fruit total soluble solids, titratable acidity and firmness and improved the taste index. Salt-responsive marker genes identified in Moneymaker were also induced in cherry tomato but not at the highest salt concentrations. Our results indicated that cherry tomato treated with 25 mM NaCl produced fruit with improved quality in comparison with non-salinized control plants without compromising yield, while at 50 and 75 mM the improved fruit quality was accompanied by a reduction in yield.