الفهرس 
Introduction
Yield components and biochemical aspects of yielded grains grainsOnly 14 pages are availabe for public view
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Abstract
A pot experiment was conducted to evaluate the beneficial effect of grain presoaking of spermine (0.2 mM), spermidine (0.35 mM) and their interaction on seawater tolerance of wheat plants (Triticum aestivum L.) v. Sakha 93 . The obtained results showed that seawater caused noticeable decreases in root length, root and shoot fresh masses, dry mass of root and shoot, leaf area, number of adventitious root, pigments content, polysaccharides, total carbohydrates and total nitrogen at heading and anthesis stages. Exogenous application of Spm, Spd or their interaction could counteract the adverse effects of seawater 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, improving all carbohydrate and nitrogen fractions. 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 seawater stress. Seawater at all used concentration increase flag leaf thickness, xylem area, number of hairs and motor cells but decrease phloem area. The used chemicals cause additional increase in the previous parameters and also the phloem area and so the nutrient move more to grains. Seawater 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. Grain priming with spermine, spermidine or their interaction alleviated the stress induced through seawater salinity by keeping water within leaves, recovering the turgidity and decreasing ABA content in flag leaf of seawater-stressed wheat plants. Furthermore, the effect was more pronounced with Spm+Spd treatment. Seawater at all examined levels caused an increases in osmotic pressure, proline, organic acids, total soluble sugars, total soluble nitrogen, Na+ , chloride and calcium . On the other hand, seawater decreased K+ and K+/ Na+ in flag leaves of wheat plants. The applied chemicals mitigated the effect of seawater and the effect was more pronounced with Spm+Spd treatment on wheat plans. The used chemicals increased the osmotic pressure and the osmolytes concentrations. Irrigation of wheat plants with diluted seawater 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 toxic ions in seawater on yield components and the biochemical aspects of yielded grains. The effect was more pronounced with Spm+Spd treatment.