Growth, Yield, and Postharvest Attributes of Glasshouse Tomatoes Produced under Deficit Irrigation

Abstract

In glasshouse-grown tomatoes ( Lycopersicon esculentum Mill. `Virosa'), deficit irrigation (DI), in which plant water potential was allowed to decrease from –0.5 to –1.2 MPa, reduced plant growth and fruit yield, size and count, and caused blossom-end rot. Deficit-irrigated fruit had higher color intensity, lower water content, and higher concentration of sucrose, glucose, and fructose than well-watered (control) fruit. Fruit concentrations of Ca, Mg, and K were the same for both treatments on a dry weight basis, but they were higher in DI fruit than in control fruit on a fresh weight basis. Fruit gas exchange was measured for two 30-day-apart harvests. For both harvests, DI fruit produced higher quantities of CO 2 and ethylene than control fruit. Ethylene and CO 2 production peaks coincided for the first harvest in both treatments. In the second harvest, the CO 2 production peak preceded that of ethylene. Despite yield reduction, DI enhanced fruit desirability in terms of higher concentration of soluble sugars and higher color intensity.