Evaluation of changes in morphological, physiological and biochemical traits of some canola cultivars under salinity stress

To investigate the effects of salinity stress on canola, ten cultivars of spring canola obtained from Karaj Seed and Plant Improvement Institute, were evaluated in vegetative growth stage in the greenhouse of Payam-e- Noor University of Mahabad, in 2017. The experiment was carried out in two salinity levels of Sodium Chloride (zero (control) and 250 mM) using a hydroponic system. Traits were measured at the end of rosette and before the stem elongation stages, after two weeks of salinity stress. The results showed that in addition to morphological depreciation, salinity stress caused imbalance in ionic concentration, increased Na+ concentration, and decreased K+ and K+/Na+. Meanwhile amount of the electrolyte leakage, proline and glycine betaine was higher under stress than control condition while the RWC was decreased. Generally, the most tolerant and succeptible cultivars were SW5001 and Sarigol respectively.  Traits such as plant dry weight, chlorophyll index and K+/Na+ were 10.89, 41.53 and 16.80 respectively in tolerant SW5001 cultivar and were of 8.70, 38.10 and 8.25, respectively in Sarigol succeptible variety. Therefore, there was diversity between the studied cultivars in terms of response to salinity stress, which could be used in complementary studies and ultimately in plant breeding programs.