title: [Effects of NaCl stress on leaf photosynthesis characteristics and free amino acid metabolism of Heyedysarum scoparium].
abstract: This paper studied the variations of leaf photosynthesis gas exchange, chlorophyll fluorescence, and free amino acid contents of Heyedysarum scoparium under the stress of different concentration NaCl, aimed to understand the effects of salt stress on the leaf physiological characteristics and free amino acid metabolism of the plant. Under mild salt stress, the photo-damage of the leaf photosystem II was avoided via the dissipation of excess excitation energy, and stomatal limitation was the main factor reducing the photosynthesis rate. With the increase of salt stress, the leaf photoprotection was not sufficient to avoid oxidative damage, and thus, the damage to photosystem II happened. Under the stress of 200 mmol NaCl x L(-1), non-stomatal limitation was the main factor responsible for the inhibition of photosynthesis. The accumulation and metabolism of major free amino acids in H. scoparium leaves varied under salt stress. Under mild salt stress, the major free amino acids such as proline, glutamate, aspartate, and alanine had a significant accumulation, but with the further increase of salt stress, the aspartate and alanine contents in H. scoparium leaves decreased, while the synthesis and accumulation of praline increased.
authors.affiliation: Ministry of Education Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas, Northwest A & F University, Yangling 712100, Shaanxi, China. hnyanhui@yeah.net
authors.forename: Hui
authors.initials: H
authors.lastname: Yan
authors.forename: Xiao-Bang
authors.initials: XB
authors.lastname: Peng
authors.forename: Jian-Jie
authors.initials: JJ
authors.lastname: Xue
mesh_terms: D000596:Amino Acids / Q000378:metabolism*; D007887:Fabaceae / Q000378:metabolism / Q000502:physiology*; D010788:Photosynthesis / Q000502:physiology*; D018515:Plant Leaves / Q000502:physiology; D012965:Sodium Chloride / Q000494:pharmacology*; D013312:Stress, Physiological / Q000502:physiology*
chemical_list: D000596:Amino Acids; D012965:Sodium Chloride