Induction of osmotic stress resistance by seed osmo-priming in winter wheat (Triticum aestivum L.) during post-germinative stages

The potential of wheat (Triticum aestivum) seed osmo-priming for post-germinative osmo-stress resistance was evaluated. Further, for comparative evaluation of seed osmo-priming and plant stress-acclimation, a set of plants was stress-acclimated prior to osmo-stress treatment. Under osmo-stress at the post-germination stage, plants from osmo-primed seeds produced 2.3% higher root biomass, 21.6% longer roots, accumulated 15.1% higher soluble sugar content and respectively, 10.4 and 12.8% higher activity of SOD and POD in the roots compared with plants from unprimed seeds. At the post-seedling establishment stage, seed-osmo-primed plants produced 29.9% higher root biomass, 15.2% longer roots, accumulated 32.7% higher soluble sugar content and 31.2% higher proline content in the roots, while the activity of SOD and POD was respectively, 19.6 and 13.1% higher than the unprimed plants. Plant stress-acclimation induced osmo-stress tolerance was exemplified by 6.9% higher root biomass, 4.6% longer roots, 52.7% higher soluble sugar content in roots, 23.9% higher proline content in the roots and 27.0% higher activity of SOD in the roots under osmo-stress when compared with the unprimed plants. The data of seedling morphology and physiological activity under control conditions showed adverse effects of stress acclimation whereas seed osmo-priming-induced stress resistance resulted in advanced germination and higher osmolyte accumulation.