اثر تنش شوری بر مقادیر سدیم، پتاسیم و عملکرد دانه در ارقام تجاری و بومی گندم (.Triticum aestivum L)

In order to assess the effect of salt stress on grain yield, sodium and potassium contents and their ratio as indicators for salinity tolerance in wheat, a factorial experiment based on a completely randomized design with three replications was carried out with sixteen wheat cultivars (eight commercial and eight landrace cultivars) and three salinity levels. The experiment was conducted at the greenhouse of the Department of Crop Production and Plant Breeding, Shiraz University. Significant differences were observed between the cultivars as well as the levels of salinity in terms of grain yield, sodium and potassium contents and K+/Na+ ratio. There are significant differences between the cultivars for yield indices including mean productivity (MP), geometric mean productivity (GMP), and stress tolerance index (STI). Yield in salt stress conditions showed significant correlation with the yield indices. Salt stress caused accumulation of sodium in plant shoots, while grain yield, potassium content and K+/Na+ ratio significantly reduced. A positive and significant correlation was observed between K+/Na+ in stress conditions and the yield indices. The results showed that, in addition to the yield indices, sodium, potassium and the ratio K+/Na+ are good indicators for screening salt tolerant bread wheat cultivars. Kavir cultivar followed by Hoosi (a landrace cultivar), were the most salt tolerant cultivars tolerant varieties was the highest amount of salinity tolerance which can be used in breeding programs aimed at improvement of salt tolerance.