Long-term hyperthermia impairs activity of both photosystems
M A Kozuleva1,2, E A Lysenko3, A A Klaus1
1Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, ul. Botanicheskaya 35, Moscow, 127276, Russia.
Abstract:
This is the first study to perform a simultaneous analysis of the activity of photosystem 1 and photosystem 2 after long-term exposure to elevated temperature. It was found that the quantum yield of photochemical reactions decreases in both photosystems. It is shown that, in photosystem 2, the regulated nonphotochemical quenching decreases whereas the unregulated non-photochemical quenching increases. In photosystem 1, limitation on both acceptor and donor sides increases.
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