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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 CO2 and ethylene than control fruit. Ethylene and CO2 production peaks coincided for the first harvest in both treatments. In the second harvest, the CO2 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.

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Sweet pepper (Capsicum annuum L.) plants were grown using Nutrient Film Technique (NFT) at electrical conductivity (EC) levels of 2 ,4, 6, 8, and 10 mS cm -1 . Higher EC levels were achieved by adding concentrated KC1 solution to the basic nutrient solution maintained at EC 2 mS cm -1 . An additional treatment of high Ca with EC 10 mS cm -1 was made up of a solution of KC1 and CaCl 2 at a ratio of 3:1 (w/w). High nutrient conductivities resulted in high blossom-end rot (BER) incidence. This was related to the suppression of Ca uptake and reduced accumulation in the fruit accompanied by an increase in the accumulation of Mg and particularly K. Extra Ca at the highest EC level promoted the accumulation of Ca by the fruit and reduced the incidence of BER. The reduction of Ca uptake in the fruit at higher EC was more pronounced at the blossom-end of the fruit. Fractionation of Ca compounds revealed that higher EC levels reduced the physiologically active acetic acid soluble component, particularly during the BER sensitive rapid fruit growth stage.