title: Enhanced salt-induced antioxidative responses involve a contribution of polyamine biosynthesis in grapevine plants.
abstract: The possible involvement of polyamines in the salt stress adaptation was investigated in grapevine (Vitis vinifera L.) plantlets focusing on photosynthesis and oxidative metabolism. Salt stress resulted in the deterioration of plant growth and photosynthesis, and treatment of plantlets with methylglyoxal-bis(guanylhydrazone) (MGBG), a S-adenosylmethionine decarboxylase (SAMDC) inhibitor, enhanced the salt stress effect. A decrease in PSII quantum yield (Fv/Fm), effective PSII quantum yield (Y(II)) and coefficient of photochemical quenching (qP) as well as increases in non-photochemical quenching (NPQ) and its coefficient (qN) was observed by these treatments. Salt and/or MGBG treatments also triggered an increase in lipid peroxidation and reactive oxygen species (ROS) accumulation as well as an increase of superoxide dismutase (SOD) and peroxidase (POX) activities, but not ascorbate peroxidase (APX) activity. Salt stress also resulted in an accumulation of oxidized ascorbate (DHA) and a decrease in reduced glutathione. MGBG alone or in combination with salt stress increased monodehydroascorbate reductase (MDHAR), SOD and POX activities and surprisingly no accumulation of DHA was noticed following treatment with MGBG. These salt-induced responses correlated with the maintaining of high level of free and conjugated spermidine and spermine, whereas a reduction of agmatine and putrescine levels was observed, which seemed to be amplified by the MGBG treatment. These results suggest that maintaining polyamine biosynthesis through the enhanced SAMDC activity in grapevine leaf tissues under salt stress conditions could contribute to the enhanced ROS scavenging activity and a protection of photosynthetic apparatus from oxidative damages.
authors.affiliation: Laboratoire Biotechnologies Végétales, Ecologie et Valorisation des Ecosystèmes, Faculté des Sciences, Université Chouaib Doukkali, 24000 El Jadida, Morocco.
authors.forename: Fatima Ezzohra
authors.initials: FE
authors.lastname: Ikbal
authors.affiliation: Group of Fruit Trees Biotechnology, Dept. Plant Breeding, CEBAS-CSIC, Campus Universitario de Espinardo, P.O. Box 164, Murcia E-30100, Spain.
authors.forename: José Antonio
authors.initials: JA
authors.lastname: Hernández
authors.affiliation: Group of Fruit Trees Biotechnology, Dept. Plant Breeding, CEBAS-CSIC, Campus Universitario de Espinardo, P.O. Box 164, Murcia E-30100, Spain.
authors.forename: Gregorio
authors.initials: G
authors.lastname: Barba-Espín
authors.affiliation: Laboratoire Biotechnologies Végétales, Ecologie et Valorisation des Ecosystèmes, Faculté des Sciences, Université Chouaib Doukkali, 24000 El Jadida, Morocco.
authors.forename: Tayeb
authors.initials: T
authors.lastname: Koussa
authors.affiliation: URVVC EA 4707, UFR Sciences Exactes et Naturelles, Université de Reims Champagne Ardenne, 51687 Reims Cedex 02, France.
authors.forename: Aziz
authors.initials: A
authors.lastname: Aziz
authors.affiliation: Laboratoire Biotechnologies Végétales, Ecologie et Valorisation des Ecosystèmes, Faculté des Sciences, Université Chouaib Doukkali, 24000 El Jadida, Morocco.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Faize
authors.affiliation: Group of Fruit Trees Biotechnology, Dept. Plant Breeding, CEBAS-CSIC, Campus Universitario de Espinardo, P.O. Box 164, Murcia E-30100, Spain. Electronic address: pdv@cebas.csic.es.
authors.forename: Pedro
authors.initials: P
authors.lastname: Diaz-Vivancos
mesh_terms: D012437:Adenosylmethionine Decarboxylase / Q000378:metabolism*; D000975:Antioxidants / Q000378:metabolism*; D001205:Ascorbic Acid / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008935:Mitoguazone / Q000494:pharmacology; D018384:Oxidative Stress; D010788:Photosynthesis / Q000502:physiology*; D010937:Plant Growth Regulators / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism; D011073:Polyamines / Q000032:analysis / Q000302:isolation & purification / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological; D027843:Vitis / Q000187:drug effects / Q000201:enzymology / Q000254:growth & development / Q000502:physiology*
chemical_list: D000975:Antioxidants; D010937:Plant Growth Regulators; D010940:Plant Proteins; D011073:Polyamines; D017382:Reactive Oxygen Species; D002734:Chlorophyll; D012965:Sodium Chloride; D012437:Adenosylmethionine Decarboxylase; D005978:Glutathione; D008935:Mitoguazone; D001205:Ascorbic Acid
keywords: Antioxidative metabolism; Grapevine; Photosynthesis; Polyamines; Salt stress