Evaluation of relationship between salinity stress tolerance indices and some physiological traits in bread wheat

The deleterious effects of salinity on plant growth and development are associated with the imbalance ion in plant, decreased K+ and increased Na+, and ultimately yield loss. In order to evaluate the effects of salinity, 41 bread wheat varieties (Trticum aestivum L.) were planted in the randomized complete block design with three replications under two saline irrigation conditions, 0.631 and 11.8 dS/m, in Agriculture and Natural Resources Research Center, Kerman, Iran. The results of analysis of variance showed that the effect of salinity on the grain yield, the content of sodium, potassium, the ratio of this two ions and relative water content (RWC) in flag leaf of the genotypes was significant. The indices of mean productivity (MP), geometric mean productivity (GMP), harmonic mean (HM) and stress tolerance index (STI) were calculated based on grain yield evidence positive significant correlation with Yp (yield in non-stress conditions), Ys (yield in stress conditions) and Na+ and K+ / Na+ in stress conditions. Varieties were selected based on these indices had high performance in both environments. These varieties had the lowest reduction in K+ / Na+ and RWC. Each of these indicators, tolerance indicators or the amount of Na+, K+, K+/Na+ and RWC, can be used to select tolerant varieties depending on the plant growth stage.