Preconditioning under high par of exposure to UV-A radiation both allow acclimation of the photosynthetic apparatus of barley transferred to UV-B radiation

0423685 - ÚVGZ 2014 RIV CZ eng C - Conference Paper (international conference)
Štroch, Michal - Materová, Z. - Vrábl, D. - Šigut, Ladislav - Špunda, Vladimír
Preconditioning under high par of exposure to UV-A radiation both allow acclimation of the photosynthetic apparatus of barley transferred to UV-B radiation.
Global Change and Resilience: From Impacts to Responses : Proceedings of the 3rd annual Global Change and Resilience Conference. Brno: Global change research centre, Academy of Sciences of the Czech Republic, v. v. i, 2013 - (Stojanov, R.; Žalud, Z.; Cudlín, P.; Farda, A.; Urban, O.; Trnka, M.), s. 248-251. ISBN 978-80-904351-8-6.
[Global Change and Resilience. Brno (CZ), 22.05.2013-24.05.2013]
R&D Projects: GA MŠMT(CZ) ED1.1.00/02.0073; GA ČR GA522/09/0468
Institutional support: RVO:67179843
Keywords : barley * clorophyll fluorescence * light acclimation * photosynthesis * photosynthetic pigments * UV screening * UV-A and UV-B-radiation
Subject RIV: EH - Ecology, Behaviour

The acclimation response of the barley photosynthetic apparatus was examined aft er transfer of plants grown under low and high PAR to common conditions both with the same PAR and acute dose of UV-A and/or UV-B radiation. The aim was to evaluate how PAR received during growth aff ects the induction of regulatory and protective mechanisms during UV exposure. Contrary to UV-B radiation, UV-A exposure of barley plants acclimated to low PAR had no negative impact on the function of photosynthetic apparatus. Th e UV-A spectral region we used (350–400 nm) can be eff ectively utilised in photosynthetic reactions, thus compensating low PAR. Th e presence of UV-A radiation during acclimation to simultaneous UVA and UVB treatment not only mitigated but completely eliminated any negative eff ect of UV-B radiation on the photosynthetic function. Th e eff ect of UV-A and UV-B exposure was similar in plants grown under high PAR – causing moderately enhanced photosystem II (PSII) photoinhibition. We proposed that the ability to accumulate a considerable amount of UVscreening compounds under high PAR itself contributes to the resistance of PSII to UV-B radiation.
Permanent Link: http://hdl.handle.net/11104/0229848