4.7 Article

Photosystem II thermostability in situ: Environmentally induced acclimation and genotype-specific reactions in Triticum aestivum L

Journal

PLANT PHYSIOLOGY AND BIOCHEMISTRY
Volume 57, Issue -, Pages 93-105

Publisher

ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER
DOI: 10.1016/j.plaphy.2012.05.012

Keywords

PSII thermostability; Heat; Chlorophyll fluorescence; Acclimation; Wheat (Triticum aestivum)

Categories

Funding

  1. Russian Foundation for Basic Research [11-04-01389a, 11-04-92690a, 12-04-92101a]
  2. Russian Ministry of Science and Education [16.740.11.0176]
  3. Molecular and Cell Biology Programs of the Russian Academy of Sciences
  4. Natural Sciences and Engineering Research Council of Canada
  5. [APVV-0197-10]

Ask authors/readers for more resources

Photosystem II (PSII) thermostability and acclimation effects on PSII photochemical efficiency were analyzed in thirty field grown winter wheat (Triticum aestivum L.) genotypes using prompt chlorophyll a fluorescence kinetics before and after dark heat treatment. A gradual increase in temperature caused the appearance of K-bands at 300 us on the chlorophyll fluorescence induction curve, indicating the impairment of the PSII donor side (even by heat treatment at 38 degrees C). An increase in basal fluorescence, commonly used as a criterion of PSII thermostability, was observed beyond a temperature threshold of 44 degrees C. Moreover, an acclimation shift (increase of critical temperature) was observed at the 3.5 degrees C identified for K-band appearance, but only by 1.1 degrees C for a steep increase in F-0. The single temperature approach with regular weekly observations completed within two months using dark heat treatment at 40 degrees C demonstrated that the acclimation effect is not gradual, but occurs immediately and is associated with an increase of daily temperature maxima over 30 degrees C. The acclimated heat treated samples had less effect on the donor side of PSII, the higher fraction of active Q((S) over bar) reducing reaction centers and causing a much lower decrease of connectivity among PSII units compared to non-acclimated samples. In the non-treated plants the reduction of antennae size, increase of PSII connectivity and changes in the acceptor side occurred as a result of heat acclimation. The enhancement of PSII thermostability persisted over several weeks regardless of weather conditions. The genotype comparison identified three groups that differed either in initial PSII thermostability or in acclimation capacity; these groupings were clearly associated with the origin of the genotypes. (C) 2012 Elsevier Masson SAS. All rights reserved.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.7
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available