In vitro morphological characterization of salt tolerance in five bread wheat varieties
摘要
The present study aims to evaluate in vitro the detrimental effects of salt stress on callus induction and plant regeneration of bread wheat (Triticum aestivum L.) varieties. Endosperm-supported mature embryos were cultivated as explants to identify the most salt-tolerant variety. An acute short-term treatment was applied, where calli were directly induced on media containing 2 mg/L 2, 4-D supplemented with four salinity levels (3, 6, 9, and 12 g/L NaCl). After three weeks, all calli from each variety produced on all media were shifted to proliferation media for one week before being transferred to regeneration medium with the same salt levels. Salinity had a statistically significant effect on all parameters evaluated. At 6 and 9 g/L NaCl, the optimal percentages of regeneration were obtained by Rajae (64 and 48%) compared to other varieties. The 12 g/L NaCl level, on the other hand, was found to be intolerable for all varieties examined. The impact of salinity was also further demonstrated by a decrease in root length of regenerated plantlets with increasing salt concentration (especially at 6 and 9 g/L NaCl). Statistical analysis revealed that the varieties Rajae and Wafia were the most tolerant to salt, followed by Nassim, while the varieties Wissam and Tigre were the most sensitive.