Photosynthesis, chlorophyll fluorescence, inorganic ion and organic acid accumulations of sunflower in responses to salt and salt-alkaline mixed stress

Title:

Photosynthesis, chlorophyll fluorescence, inorganic ion and organic acid accumulations of sunflower in responses to salt and salt-alkaline mixed stress

Creator:

Liu, J. and Shi, D.-C.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:8eb777dd-9df3-4048-bf68-f7e3a4ebfefa
uuid:8eb777dd-9df3-4048-bf68-f7e3a4ebfefa
issn:0300-3604
doi:10.1007/s11099-010-0017-4

Subject:

botanika, botany, salt stress, salt-alkaline mixed stress, chlorophyll fluorescence, photosynthesis, inorganic ions, and organic acids

Type:

model:article and TEXT

Format:

bez média and svazek

Description:

Sunflowers were treated with mixing proportions of NaCl, Na2SO4, NaHCO3, and Na2CO3. Effects of salt and saltalkaline mixed stress on growth, photosynthesis, chlorophyll fluorescence, and contents of inorganic ions and organic acids of sunflower were compared. The growth of sunflower decreased with increasing salinity. The contents of photosynthetic pigments did not decrease under salt stress, but their contents decreased sharply under salt-alkaline mixed stress. Net photosynthetic rates, stomatal conductance and intercellular CO2 concentration decreased obviously, with greater reductions under salt-alkaline mixed stress than under salt one. Fluorescence parameters showed no significant differences under salt stress. However, maximal efficiency of PSII photochemistry, photochemical quenching coefficient, electron transport rate, and actual PSII efficiency significantly decreased but non-photochemical quenching increased substantially under salt-alkaline mixed stress. Under salt-alkaline mixed stress, sunflower leaves maintained a low Na+- and high K+ status; this may be an important feature of sunflower tolerance to salinity. Analysis of the mechanism of ion balance showed that K+ but not Na+ was the main inorganic cation in sunflower leaves. Our results indicated that the change in organic acid content was opposite to the change of Cl-, and the contribution of organic acid to total charge in sunflower leaves under both stresses decreased with increasing salinity. This may be a special adaptive response to stresses for sunflower. Sunflower under stress conditions mainly accumulated inorganic ions instead of synthesizing organic compounds to decrease cell water potential in order to save energy consumption. and J. Liu, D.-C. Shi.

Language:

Multiple languages

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/
policy:public

Coverage:

127-134

Source:

Photosynthetica | 2010 Volume:48 | Number:1

Harvested from:

CDK

Metadata only:

false