Effect of salinity on root characteristics and ionic distribution of six bread wheat cultivars (Triticume aestivum L.)

In order to investigate the effect of salinity on some root characteristics and ion distribution, a research was carried out in a split factorial on three replications with two salinity levels (2 dS.m-1) and 16 dS.m1 (salinity) on six wheat cultivars (Atrak, Pishtaz, Chamran, Roshan, Qods, and Shiraz) and in two levels of harvest (two weeks and three weeks after planting) in greenhouse. The traits of root dry weight, shoot dry weight, shoot dry weight/root dry weight ratio, root length, total volume, sodium ion concentration, potassium ion concentration, potassium/sodium ratio in root and shoot, number of axial root, number of first and second- order lateral roots were measured. The results showed that salinity in the second and third week reduced the dry weight of root, shoot, length, root volume, axial, and first-order lateral root number in all cultivars. In the control treatment Chamran and Roshan had the highest ability to produce root and shoot dry weight respectively. Under salinity the highest root dry weight (14 and 18 mg/plant) and total root volume (78 and 93 mm3 /plant) were related to Roshan in both weeks. Qods had the lowest root dry weight with the highest drop (54% and 50%, respectively) in second and third week. The lowest total root volume in salinity of second and third week respectively was related to Qods and Shiraz (40 and 59 mm3 /plant).Qods with high root producing potential in control showed a significant decrease in the production of lateral roots and total root length in salinity. Also, Roshan cultivar, despite having the highest sodium concentration of shoots in salinity treatment, it was able to produce the highest amount of shoots due to maintaining potassium ions in roots and shoots. Based on the traits evaluated and the response of the studied cultivars to salinity, tolerance of the Roshan cultivar and susceptibility of Qods cultivar to salinity arecompatible with previous study at this stage of growth.