title: Physiological and molecular features of Puccinellia tenuiflora tolerating salt and alkaline-salt stress.
abstract: Saline-alkali soil seriously threatens agriculture productivity; therefore, understanding the mechanism of plant tolerance to alkaline-salt stress has become a major challenge. Halophytic Puccinellia tenuiflora can tolerate salt and alkaline-salt stress, and is thus an ideal plant for studying this tolerance mechanism. In this study, we examined the salt and alkaline-salt stress tolerance of P. tenuiflora, and analyzed gene expression profiles under these stresses. Physiological experiments revealed that P. tenuiflora can grow normally with maximum stress under 600 mmol/L NaCl and 150 mmol/L Na2 CO3 (pH 11.0) for 6 d. We identified 4,982 unigenes closely homologous to rice and barley. Furthermore, 1,105 genes showed differentially expressed profiles under salt and alkaline-salt treatments. Differentially expressed genes were overrepresented in functions of photosynthesis, oxidation reduction, signal transduction, and transcription regulation. Almost all genes downregulated under salt and alkaline-salt stress were related to cell structure, photosynthesis, and protein synthesis. Comparing with salt stress, alkaline-salt stress triggered more differentially expressed genes and significantly upregulated genes related to H(+) transport and citric acid synthesis. These data indicate common and diverse features of salt and alkaline-salt stress tolerance, and give novel insights into the molecular and physiological mechanisms of plant salt and alkaline-salt tolerance.
authors.affiliation: Key Laboratory of Plant Molecular Physiology, Institute of Botany, the Chinese Academy of Sciences, National Center for Plant Gene Research, Beijing 100093, China.
authors.forename: Xia
authors.initials: X
authors.lastname: Zhang
authors.forename: Liqin
authors.initials: L
authors.lastname: Wei
authors.forename: Zizhang
authors.initials: Z
authors.lastname: Wang
authors.forename: Tai
authors.initials: T
authors.lastname: Wang
mesh_terms: D002254:Carbonates / Q000494:pharmacology; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000187:drug effects / Q000235:genetics; D006109:Poaceae / Q000187:drug effects* / Q000378:metabolism*; D055049:Salt Tolerance / Q000235:genetics / Q000502:physiology; D055051:Salt-Tolerant Plants / Q000187:drug effects / Q000378:metabolism; D012965:Sodium Chloride / Q000494:pharmacology
chemical_list: D002254:Carbonates; D012965:Sodium Chloride; C005686:sodium carbonate