Salicylic acid and osmotic stress effects on seed germination and seedling growth of wheat (Triticum aestivum L.) cultivars

Abstract

Low seed germination and seedling stand establishment are main factors in dryland farming for winter wheat production in low rainfall regions (<300 mm annual rainfall) of Iran. Previous studies have shown that salicylic acid (SA) plays positive roles to plants responses to osmotic stress. Therefore, the influence of seed treatment with salicylic acid on germination and seedling growth under drought stress was studied with two wheat cultivars; Roshan as a tolerant and Mahdavi as an intolerant cultivar to osmotic stress. The results showed osmotic stress (10% and 20% PEG) reduced germination percentage, growth rate, vigor index, seedling length and dry weight and also increased leaf cells electrolyte leakage. The effect of 20% PEG was more severe. On the contrary, SA (0.1 and 0.5 mM) significantly improved germination and seedling indices and cultivars responded similarly to interaction of drought and SA. SA, especially at 0.5 mM alleviated the adverse effects of osmotic stress on most recorded parameters. Therefore, it is concluded that SA may have improve germination and seedling growth and establishment of wheat in dryland farming.