الفهرس 
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Abstract
A pot experiment was conducted to evaluate the beneficial effect of grain presoaking of spermine (0.15 mM), spermidine (0.3 mM) and their interaction on waste water tolerance of wheat plants (Triticum aestivum L.) variety Sakha 94 . The obtained results showed that waste water caused noticeable decreases in root length, root and shoot fresh masses, leaf area, pigments content, soluble sugars and nitrogen. On the other hand, waste water caused a massive increases in dry mass of root. Exogenous application of Spm, Spd or their interaction could counteract the adverse effects of waste water (mostly polluted with heavy metals) by improvement of growth vigor of root and shoot, leaf area, retention of pigments content, increasing the concentration of organic solutes (soluble sugars and soluble nitrogen) as osmoprotectants, keeping out the polysaccharides concentration and/or stabilization of essential proteins in wheat plants. The application of Spm, Spd or their interaction induced some modifications in the anatomical features of the flag leaf and peduncle of main shoot which appeared to be an adaptive response to waste water stress. Waste water induced marked decreases in relative water content and water use efficiency but led to a significant increase in the saturation water deficit and abscisic acid (ABA) concentration in flag leaves of wheat plants but significantly increased heavy metals content in roots of wheat plants. Grain priming with spermine, spermidine or their interaction alleviated the stress induced by heavy metals in waste water by keeping water within leaves, recovering the turgidity and decreasing ABA content in flag leaf of waste water-stressed wheat plants. Furthermore, the effect was more pronounced with Spm+Spd treatment. Waste water at all examined levels caused an increases in osmotic pressure, proline, organic acids, chloride and heavy metals content (Cd++, Pb++, Cu++, Ni++ & Zn++) as well as Na+/K+ ratio. On the other hand, waste water decreased total soluble nitrogen, total soluble sugars and ions (Na+, K+ &Ca++) in flag leaves of wheat plants. The applied chemicals mitigated the effect of waste water and the effect was more pronounced with Spm+Spd treatment on wheat plans. The used chemicals increased the osmotic pressure and the osmolytes concentrations. The osmotic pressure appeared to depend mainly on proline, organic acids, chloride and heavy metals content. Irrigation of wheat plants with waste water stress decreased significantly all yield components (spike length, number of spikelets / main spike, 100 kernel weight, grain number / spike, grain yield / spike, grain yield / plant, straw yield / plant, crop yield / plant, harvest, mobilization and crop indices). The applied polyamines appeared to alleviate the effect of heavy metals stress in waste water on yield components and the biochemical aspects of yielded grains. The effect was more pronounced with Spm Spd treatment.