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Comparative metabolic responses and adaptive strategies of wheat (Triticum aestivum) to salt and alkali stress.

Guo R, Yang Z, Li F, Yan C, Zhong X, Liu Q, Xia X, Li H, Zhao L - BMC Plant Biol. (2015)

Bottom Line: High-pH of alkali stress induced the most of phosphate and metal ions to precipitate; as a result, the availability of nutrients significantly declined.These outcomes correspond to specific detrimental effects of a highly pH environment.Alkali stress (at high pH) significantly inhibited photosynthetic rate; thus, sugar production was reduced, N metabolism was limited, amino acid production was reduced, and glycolysis was inhibited.

View Article: PubMed Central - PubMed

Affiliation: Institute of Environment and Sustainable Development in Agriculture (IEDA), Chinese Academy of Agricultural Sciences (CAAS)/Key Laboratory of Dryland Agriculture, Ministry of Agriculture, Beijing, 100081, P.R. China. guor219@yahoo.com.

ABSTRACT

Background: It is well known that salinization (high-pH) has been considered as a major environmental threat to agricultural systems. The aim of this study was to investigate the differences between salt stress and alkali stress in metabolic profiles and nutrient accumulation of wheat; these parameters were also evaluated to determine the physiological adaptive mechanisms by which wheat tolerates alkali stress.

Results: The harmful effect of alkali stress on the growth and photosynthesis of wheat were stronger than those of salt stress. High-pH of alkali stress induced the most of phosphate and metal ions to precipitate; as a result, the availability of nutrients significantly declined. Under alkali stress, Ca sharply increased in roots, however, it decreased under salt stress. In addition, we detected the 75 metabolites that were different among the treatments according to GC-MS analysis, including organic acids, amino acids, sugars/polyols and others. The metabolic data showed salt stress and alkali stress caused different metabolic shifts; alkali stress has a stronger injurious effect on the distribution and accumulation of metabolites than salt stress. These outcomes correspond to specific detrimental effects of a highly pH environment.

Conclusions: Ca had a significant positive correlation with alkali tolerates, and increasing Ca concentration can immediately trigger SOS Na exclusion system and reduce the Na injury. Salt stress caused metabolic shifts toward gluconeogenesis with increased sugars to avoid osmotic stress; energy in roots and active synthesis in leaves were needed by wheat to develop salt tolerance. Alkali stress (at high pH) significantly inhibited photosynthetic rate; thus, sugar production was reduced, N metabolism was limited, amino acid production was reduced, and glycolysis was inhibited.

No MeSH data available.


Related in: MedlinePlus

Effects of salt stress (SS) and alkali stress (AS) on relative growth rate (RGR) of leaves (a) and roots (b), net photosynthetic rate (PN) (c), stomatal conductance (gs) (d), intercellular CO2 concentration (Ci) (e), transpiration rate (E) (f), chlorophyll a (Chl a) (g) and b (Chl b) contents (h), and carotenoid (Car) (i) content of wheat. Values are means of five replicates. Means followed by different letters in the same stress type are significantly different at p < 0.05 according to Duncan’s method
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Fig1: Effects of salt stress (SS) and alkali stress (AS) on relative growth rate (RGR) of leaves (a) and roots (b), net photosynthetic rate (PN) (c), stomatal conductance (gs) (d), intercellular CO2 concentration (Ci) (e), transpiration rate (E) (f), chlorophyll a (Chl a) (g) and b (Chl b) contents (h), and carotenoid (Car) (i) content of wheat. Values are means of five replicates. Means followed by different letters in the same stress type are significantly different at p < 0.05 according to Duncan’s method

Mentions: The growth of wheat seedling leaves and roots decreased under salinity stress compared with that of the control group; the growth of these parts was reduced to a greater extent under alkali stress than under salt stress (Figs. 1a and b, p < 0.05). The photosynthetic indices of plants exposed to salt and alkali stress were lower than those of the control plants; however, these parameters decreased sharply under alkali stress (Figs. 1c–f, p < 0.05). Pigment contents were not significantly affected by salt stress, but Chl and Car contents decreased remarkably in plants under alkali stress compared with those in the control plants (Figs. 1g–i, p < 0.05).Fig. 1


Comparative metabolic responses and adaptive strategies of wheat (Triticum aestivum) to salt and alkali stress.

Guo R, Yang Z, Li F, Yan C, Zhong X, Liu Q, Xia X, Li H, Zhao L - BMC Plant Biol. (2015)

Effects of salt stress (SS) and alkali stress (AS) on relative growth rate (RGR) of leaves (a) and roots (b), net photosynthetic rate (PN) (c), stomatal conductance (gs) (d), intercellular CO2 concentration (Ci) (e), transpiration rate (E) (f), chlorophyll a (Chl a) (g) and b (Chl b) contents (h), and carotenoid (Car) (i) content of wheat. Values are means of five replicates. Means followed by different letters in the same stress type are significantly different at p < 0.05 according to Duncan’s method
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4492011&req=5

Fig1: Effects of salt stress (SS) and alkali stress (AS) on relative growth rate (RGR) of leaves (a) and roots (b), net photosynthetic rate (PN) (c), stomatal conductance (gs) (d), intercellular CO2 concentration (Ci) (e), transpiration rate (E) (f), chlorophyll a (Chl a) (g) and b (Chl b) contents (h), and carotenoid (Car) (i) content of wheat. Values are means of five replicates. Means followed by different letters in the same stress type are significantly different at p < 0.05 according to Duncan’s method
Mentions: The growth of wheat seedling leaves and roots decreased under salinity stress compared with that of the control group; the growth of these parts was reduced to a greater extent under alkali stress than under salt stress (Figs. 1a and b, p < 0.05). The photosynthetic indices of plants exposed to salt and alkali stress were lower than those of the control plants; however, these parameters decreased sharply under alkali stress (Figs. 1c–f, p < 0.05). Pigment contents were not significantly affected by salt stress, but Chl and Car contents decreased remarkably in plants under alkali stress compared with those in the control plants (Figs. 1g–i, p < 0.05).Fig. 1

Bottom Line: High-pH of alkali stress induced the most of phosphate and metal ions to precipitate; as a result, the availability of nutrients significantly declined.These outcomes correspond to specific detrimental effects of a highly pH environment.Alkali stress (at high pH) significantly inhibited photosynthetic rate; thus, sugar production was reduced, N metabolism was limited, amino acid production was reduced, and glycolysis was inhibited.

View Article: PubMed Central - PubMed

Affiliation: Institute of Environment and Sustainable Development in Agriculture (IEDA), Chinese Academy of Agricultural Sciences (CAAS)/Key Laboratory of Dryland Agriculture, Ministry of Agriculture, Beijing, 100081, P.R. China. guor219@yahoo.com.

ABSTRACT

Background: It is well known that salinization (high-pH) has been considered as a major environmental threat to agricultural systems. The aim of this study was to investigate the differences between salt stress and alkali stress in metabolic profiles and nutrient accumulation of wheat; these parameters were also evaluated to determine the physiological adaptive mechanisms by which wheat tolerates alkali stress.

Results: The harmful effect of alkali stress on the growth and photosynthesis of wheat were stronger than those of salt stress. High-pH of alkali stress induced the most of phosphate and metal ions to precipitate; as a result, the availability of nutrients significantly declined. Under alkali stress, Ca sharply increased in roots, however, it decreased under salt stress. In addition, we detected the 75 metabolites that were different among the treatments according to GC-MS analysis, including organic acids, amino acids, sugars/polyols and others. The metabolic data showed salt stress and alkali stress caused different metabolic shifts; alkali stress has a stronger injurious effect on the distribution and accumulation of metabolites than salt stress. These outcomes correspond to specific detrimental effects of a highly pH environment.

Conclusions: Ca had a significant positive correlation with alkali tolerates, and increasing Ca concentration can immediately trigger SOS Na exclusion system and reduce the Na injury. Salt stress caused metabolic shifts toward gluconeogenesis with increased sugars to avoid osmotic stress; energy in roots and active synthesis in leaves were needed by wheat to develop salt tolerance. Alkali stress (at high pH) significantly inhibited photosynthetic rate; thus, sugar production was reduced, N metabolism was limited, amino acid production was reduced, and glycolysis was inhibited.

No MeSH data available.


Related in: MedlinePlus