Lipid changes in solanum nigrum calli grown under salt stress

ABSTRACT

Calli have been induced on an axenic hypocotyl explants excisized from germinated seeds of Solarium nigrum under tissue culture techniques using MS-medium supplemented with 0.3 mg/L NAA and 2.0 mg/L kinetin. Calli were then removed and subcultured on medium either without salt [control] or provided with either of NaCl concentrations [50, 100, 150 and 200 mM] then kept growing at 28degree 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 [70 percent] specially at the higher salt concentrations [150, 200 mM] became necrotic. Those that survived and adapted to salt medium subsequently grew more quickly than controls especially at lower salt concentrations [50, 100 mM]. Calli collected and subjected immediately for the lipid analysis. The results obtained showed with the slight increase of NaCl [50, 100 mM], no significant changes detected in neutral or phospholipids, but at the higher NaCl concentrations [150, 200 mM] most of the individual classes of neutral, phospho and the total lipids have shown a significant decrease. Few lipid classes have an increase at the higher salinity levels [150, 200 mM] e.g., diacyl glycerol and sterol from neutral lipids and phosphatidic acid from the phospholipids