Role of Ascorbic Acid in the Initiation and Growth of Helianthus annuus L. Callus under Salt Stress Conditions


The research included study the effect of sodium chloride NaCl salt with concentrations 50, 100, 150 and 200 mM and ascorbic acid concentrations 20, 40 mg/ l-1 in the initiation and growth of Helianthus annuus L. callus. The results showed that increasing salt concentration in cultured media led to decrease callus induction from stem segments of seedlings that grown on agar-solidified Murashige and Skoog medium (MS) provided with 1 mg/ l-1 of BA and 0.5 mg/ l-1 of NAA. This was accompanied by a decrease in the fresh and dry weights of callus, whereas, the addition of ascorbic acid to media containing salt resulted in a restoration of the initiation and growth of callus after 30 days of cultivation. The results also showed that cultivation of samples of callus in MS media with different concentrations of NaCl led to a significant decrease in the indicators of callus growth (fresh and dry weight, salt stress index, absolute and relative rates, callus viability) with an increase in electrolyte leakage of callus cells. The addition of ascorbic acid 20 or 40 mg/ l-1 to MS media encourages the callus growth indicators above with the superior concentration 20 mg/ l-1. The presence of ascorbic acid, especially 20 mgl-1 in growing media containing NaCl at 150 mM, increased the callus content of ascorbic acid as compare to salt treatment only, after 21 days of cultivation.