caa a22 4500 605481156 CHVBK 20210128100419.0 cr unu---uuuuu 210128e20150601xx s 000 0 eng 10.1007/s11099-015-0113-6 doi (NATIONALLICENCE)springer-10.1007/s11099-015-0113-6 Effect of drought stress on the photosynthesis of Acacia tortilis subsp. raddiana at the young seedling stage [Elektronische Daten] [S. Kebbas, S. Lutts, F. Aid] Water stress usually impairs photosynthesis and plant growth. Acacia tortilis subsp. raddiana is well adapted to dry environments. The aim of the present study was to determine the impact of a progressive decrease in soil water content on photosynthetic-related parameters at the young seedling stage. Drought-induced plant responses occurred according to two types of kinetics. Water potential, stomatal conductance, and transpiration rates were rapidly affected by a decrease in soil water content, while chlorophyll fluorescence-related parameters and chlorophyll concentrations decreased only when soil water content was lower than 40%. The maximal efficiency of PSII photochemistry in the dark-adapted state remained unaffected by the treatment, whatever the stress duration. A. raddiana accumulated high concentrations of soluble sugars in relation to a stress-induced early stimulation of sucrose-phosphate synthase activity, while stimulation of invertase and sucrose synthase led to fructose accumulation only at the end of the stress period. We suggested that sugar accumulation may be involved in osmotic adjustment and protection of stressed tissues. A. raddiana was thus able to protect its photosynthetic machinery under drought conditions and may be considered as a promising species for revegetation of dry areas. The Institute of Experimental Botany, 2015 gas exchange nationallicence growth parameters nationallicence stomata nationallicence sugar metabolism nationallicence water-use efficiency nationallicence Chl : chlorophyll nationallicence DM : dry mass nationallicence E : instantaneous transpiration nationallicence ED : density of epidermal pavement cells nationallicence ETR : electron transfer rate nationallicence F0 : the minimal fluorescence in the dark-adapted state nationallicence Fm : the maximal fluorescence in the dark-adapted state nationallicence FM : fresh mass nationallicence g s : stomatal conductance nationallicence LA : leaf area nationallicence NPQ : nonphotochemical quenching nationallicence P N : net photosynthesis nationallicence qP : photochemical quenching nationallicence RWC : relative water content nationallicence SD : stomatal density nationallicence SI : stomatal index nationallicence SLA : specific leaf area nationallicence SPS : sucrose-phosphate-synthase nationallicence SuSy : sucrose synthase nationallicence SWC : soil water content nationallicence WUE : water-use efficiency nationallicence ΨW : shoot water potential nationallicence ΨS : shoot osmotic potential nationallicence ΦPSII : actual PSII efficiency nationallicence Kebbas S. Département de Biologie, Faculté des Sciences de la Nature et de la Vie, Université Blida 1, route de Soumaa, BP 270, 09100, Blida, Algeria aut Lutts S. Groupe de Recherche en Physiologie Végétale, Earth and Life Institute, Université Catholique de Louvain, 5 Place Croix du Sud, 1348, Louvain-la-Neuve, Belgium aut Aid F. Equipe de Physiologie Végétale, LBPO, FSB, Université des Sciences et de la Technologie Houari Boumediene, BP 32 El Alia, 16111, Bab Ezzouar-Algiers, Algeria aut Photosynthetica The Institute of Experimental Biology of the Czech Academy of Sciences 53/2(2015-06-01), 288-298 0300-3604 53:2<288 2015 53 11099 https://doi.org/10.1007/s11099-015-0113-6 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s11099-015-0113-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Kebbas S. Département de Biologie, Faculté des Sciences de la Nature et de la Vie, Université Blida 1, route de Soumaa, BP 270, 09100, Blida, Algeria aut NATIONALLICENCE 700 1- Lutts S. Groupe de Recherche en Physiologie Végétale, Earth and Life Institute, Université Catholique de Louvain, 5 Place Croix du Sud, 1348, Louvain-la-Neuve, Belgium aut NATIONALLICENCE 700 1- Aid F. Equipe de Physiologie Végétale, LBPO, FSB, Université des Sciences et de la Technologie Houari Boumediene, BP 32 El Alia, 16111, Bab Ezzouar-Algiers, Algeria aut NATIONALLICENCE 773 0- Photosynthetica The Institute of Experimental Biology of the Czech Academy of Sciences 53/2(2015-06-01), 288-298 0300-3604 53:2<288 2015 53 11099