Sodium Chloride Salt Tolerance Evaluation and Classification of Spring Rapeseed (Brassica napus L.)

Abiotic stresses such as salinity, are factors that severely affects agricultural production. To evaluate the effects of salinity on some morphological and physiological traits related to salt tolerance of 22 genotypes of spring rapeseed cultivars in the vegetative growth stage, an experiment was conducted as a split plot form based on Randomized Complete Blocks Design using levels of salinity: zero (control), 150 and 300 mM sodium chloride with three replications were done in the research greenhouse of Tabriz university. In present study, dry weight of shoot and root, height, Na+ and K+ contents of leaves and roots, K+/Na+ ratios in leaves and roots were measured. Increasing salinity levels have significantly increase Na+ contents of leaves and roots and reduced traits such as height, shoot and root dry weight, K+ contents and K+/Na+ ratios of leaves and roots. Cultivars showed the most significant differences, this shows that high diversity of genotypes in salinity tolerance. Cluster analysis led to the separation of genotypes into four groups. Results showed that SAN-2 was the most tolerant and the Amica was the most sensitive to salt stress during vegetative growth, respectively. Therefore They can be used to identify genes loci determination and understand the mechanisms salt tolerance genes.