الفهرس 
Stomatal movement under salt stress conditionsOnly 14 pages are availabe for public view
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Abstract
The effect of foliar application of either salicylic acid (0.5 mM) or putrescine (2 mM) on cowpea plants grown at 100 and 200 mM NaCl throughout the growth period were studied. The changes in growth criteria, metabolic and biochemical reactions as well as the yield components were estimated in response to the applied treatments. Foliar application of salicylic acid or putrescine significantly increase the growth parameters, stomatal movement, photosynthetic pigments, total soluble and insoluble carbohydrates, total soluble protein and nucleic acids in stressed cowpea shoots and roots compared to their corresponding controls grown at 100 and 200 mM NaCl. Application of either salicylic acid or putrescine increase the absorption, accumulation and transport rates of both K+ and Ca++ however, a reverse trends observed for Na+ in salinized cowpea plants. New proteins were expressed in salinized shoots (92.8 KDa) and roots (19.66 KDa) of cowpea plants. Salicylic acid and putrescine treatments induced the expression of proteins with molecular weights 28.0, 30.0 and 33.5 KDa in shoots and 53.0 KDa in roots of cowpea plants grown at 200 mM NaCl. The oxidative damage induced by salt stress could be mitigated by application of either salicylic acid or putrescine. Salicylic acid and putrescine enhance the oxidative defense system in salinized cowpea plants by promoting the synthesis of antioxidant compounds such as ascorbic acid, glutathione and phenols as well as increasing the activities of some antioxidant enzymes (SOD, CAT, POX, ASO, APX, GR) which buffer ROS induced by salt stress thereby nullify the salt stress injuries. Furthermore, foliar spray of either salicylic acid or putrescine enhanced the yield components and improved the seed quality thereby increasing total soluble and insoluble carbohydrates and proteins, as well as increase K+ and Ca++ accumulation but decrease Na+ content in salinized yielded cowpea seeds.
Key words: Vigna sinensis, NaCl, salicylic acid, putrescine, photosynthetic pigments, stomatal movement, carbohydrates, mineral translocation, nucleic acids, amino acids, gene expression, phenols, antioxidant substances, antioxidant enzymes.