title: Differential response of NADP-dehydrogenases and carbon metabolism in leaves and roots of two durum wheat (Triticum durum Desf.) cultivars (Karim and Azizi) with different sensitivities to salt stress.
abstract: Wheat (Triticum durum Desf.) is a common Mediterranean species of considerable agronomic importance. Salinity is one of the major threats to sustainable agricultural production mainly because it limits plant productivity. After exposing the Karim and Azizi durum wheat cultivars, which are of agronomic significance in Tunisia, to 100mM NaCl salinity, growth parameters (dry weight and length), proline content and chlorophylls were evaluated in their leaves and roots. In addition, we analyzed glutathione content and key enzymatic activities, including phosphoenolpyruvate carboxylase (PEPC), NADP-isocitrate dehydrogenase (NADP-ICDH), NADP-malic enzyme (NADP-ME), glucose-6-phosphate dehydrogenase (G6PDH) and 6-phosphogluconate dehydrogenase (6PGDH), involved in the carbon metabolism and NADPH-generating system. The sensitivity index indicates that cv Karim was more tolerant to salinity than cv Azizi. This higher tolerance was corroborated at the biochemical level, as cv Karim showed a greater capacity to accumulate proline, especially in leaves, while the enzyme activities studied were differentially regulated in both organs, with NADP-ICDH being the only activity to be unaffected in all organs. In summary, the data indicate that higher levels of proline accumulation and the differential responses of some key enzymes involved in the carbon metabolism and NADPH regeneration contribute to the salinity tolerance mechanism and lead to increased biomass accumulation in cv Karim.
authors.affiliation: Group of Antioxidants, Free Radicals and Nitric Oxide in Biotechnology, Food and Agriculture, Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, CSIC, Apdo 419, E-18080 Granada, Spain; Faculty of Sciences of Tunisia, University Tunis El Manar, Tunis, Tunis.
authors.forename: Donia
authors.initials: D
authors.lastname: Bouthour
authors.affiliation: Faculty of Sciences of Tunisia, University Tunis El Manar, Tunis, Tunis.
authors.forename: Tawba
authors.initials: T
authors.lastname: Kalai
authors.affiliation: Faculty of Sciences of Tunisia, University Tunis El Manar, Tunis, Tunis.
authors.forename: Haouari C
authors.initials: HC
authors.lastname: Chaffei
authors.affiliation: Faculty of Sciences of Tunisia, University Tunis El Manar, Tunis, Tunis.
authors.forename: Houda
authors.initials: H
authors.lastname: Gouia
authors.affiliation: Group of Antioxidants, Free Radicals and Nitric Oxide in Biotechnology, Food and Agriculture, Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, CSIC, Apdo 419, E-18080 Granada, Spain. Electronic address: javier.corpas@eez.csic.es.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Corpas
mesh_terms: D018533:Biomass; D002244:Carbon / Q000378:metabolism*; D002734:Chlorophyll / Q000378:metabolism; D019803:Glutathione Disulfide / Q000378:metabolism; D009252:NADPH Dehydrogenase / Q000378:metabolism*; D010641:Phenotype; D010730:Phosphoenolpyruvate Carboxylase / Q000378:metabolism; D010788:Photosynthesis / Q000187:drug effects; D010860:Pigments, Biological / Q000378:metabolism; D018515:Plant Leaves / Q000187:drug effects / Q000378:metabolism*; D018517:Plant Roots / Q000187:drug effects / Q000378:metabolism*; D011392:Proline / Q000378:metabolism; D012965:Sodium Chloride / Q000494:pharmacology*; D013312:Stress, Physiological / Q000187:drug effects*; D014908:Triticum / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development / Q000502:physiology*
chemical_list: D010860:Pigments, Biological; D002734:Chlorophyll; D012965:Sodium Chloride; D002244:Carbon; D011392:Proline; D009252:NADPH Dehydrogenase; D010730:Phosphoenolpyruvate Carboxylase; D019803:Glutathione Disulfide
keywords: Durum wheat; Glutathione; NADP-dehydrogenases; Proline; Salinity stress