Tomato calli have been induced on an axenic hypocotyl explants excisized from germinated seeds under tissue culture techniques using MS-medium supplemented with 0.4 mg/L Naphthalene acetic acid (NAA) and 0.3 mg/L kinetin. Calli were then removed and subcultured on a medium either without salt (control) or provided with different NaCl concentrations (0.0, 50, 100, 150, and 200 mM) then kept growing at 28o C under low light intensity for 8 weeks. During the first 4 weeks, the salt treated calli grow more slowly than the control and most of them especially at the higher salt concentrations (150 and 200 mM) became necrotic. Those that grew under lower salt concentrations (50 and 100 mM) have been survived and adapted to salt medium subsequently grew more rapidly. Fresh calli collected and subjected immediately for determination of phenolic compounds and lipids. Some of the calli were oven dried for determination of carbohydrates and ion accumulation. The results obtained show that low concentration of NaCl (50 and 100 mM), induced no significant changes in neutral or phospholipids, but at the higher NaCl concentrations (150 and 200 mM) most of the individual classes of neutral, phospho and the total lipids were reduced. Also, free or bound and total phenolic compounds exhibited a significant increase. Na+ accumulation showed an increase but K+ and Ca++ exhibited a marked decrease in response to salt stress. Concerning carbohydrate contents, reducing sugars exhibited a slight decrease, while non- reducing and total sugars showed a marked increase by the increase of salt concentration.
Key words: Salt stress; Carbohydrates; Pr‾ Phenolic compounds; Ions accumulation; Lipid contents; Tissue culture; Lycopcrsicon esculentum.
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