Effects of Light Intensity on Cyclic Electron Flow Around PSI and its Relationship to Non-photochemical Quenching of Chl Fluorescence in Tobacco Leaves

The kinetics of photoinhibition in detached leaves from tomato plants (Solanium lycopersicum L. cv. M82) grown for 6 days under different combinations of optimal and moderately high temperature and optimal and high light intensity were studied. The inhibition of PSII was evaluated by changes in maximal quantum yield, the coefficient of photochemical quenching and the quantum yield of PSII. The changes of PSI activity was estimated by the redox state of P700. The involvement of different possible protective processes was checked by determination of nonphotochemical quenching and cyclic electron flow around PSI. To evaluate to what extent the photosynthetic apparatus and its response to high light treatment was affected by growth conditions, the kinetics of photoinhibition in isolated thylakoid membranes were also studied. The photochemical activities of both photosystems and changes in the energy distribution and interactions between them were evaluated by means of a Clark electrode and 77 K fluorescence analysis. The data showed an increased tolerance to photoinhibition in plants grown under a combination of moderately high temperature and light intensity, which was related to the stimulation of cyclic electron flow, PSI activity and rearrangements of pigment–protein complexes, leading to a decrease in the excitation energy delivered to PSII.

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Prediction of respective contribution of linear electron flow and PGR5-dependent cyclic electron flow to non-photochemical quenching induction

Plant Physiology and Biochemistry ◽

10.1016/j.plaphy.2014.03.017 ◽

2014 ◽

Vol 81 ◽

pp. 190-196 ◽

Cited By ~ 9

Author(s):

Ryoichi Sato ◽

Hiroyuki Ohta ◽

Shinji Masuda

Keyword(s):

Electron Flow ◽

Cyclic Electron Flow ◽

Photochemical Quenching ◽

Linear Electron ◽

Respective Contribution ◽

Non Photochemical Quenching

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Inhibition of CO2 fixation by iodoacetamide stimulates cyclic electron flow and non-photochemical quenching upon far-red illumination

Photosynthesis Research ◽

10.1007/s11120-013-9826-1 ◽

2013 ◽

Vol 115 (1) ◽

pp. 55-63 ◽

Cited By ~ 13

Author(s):

Pierre Joliot ◽

Jean Alric

Keyword(s):

Co2 Fixation ◽

Electron Flow ◽

Cyclic Electron Flow ◽

Photochemical Quenching ◽

Non Photochemical Quenching

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Coupled Regulation of Cyclic Electron Flow Around PSI with Photosynthesis — Its Contribution to Non-photochemical Quenching Evidenced with Transplastomic Tobacco Plants Over-Expressing Ferredoxin in Chloroplasts

Photosynthesis. Energy from the Sun ◽

10.1007/978-1-4020-6709-9_203 ◽

2008 ◽

pp. 923-927

Author(s):

Chikahiro Miyake

Keyword(s):

Electron Flow ◽

Cyclic Electron Flow ◽

Photochemical Quenching ◽

Tobacco Plants ◽

Transplastomic Tobacco ◽

Non Photochemical Quenching

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Exogenous putrescine alleviates photoinhibition caused by salt stress through increasing cyclic electron flow in cucumber

10.1101/301762 ◽

2018 ◽

Author(s):

Xinyi Wu ◽

Sheng Shu ◽

Yu Wang ◽

Ruonan Yuan ◽

Shirong Guo

Keyword(s):

Salt Stress ◽

Electron Flow ◽

Critical Role ◽

Photochemical Efficiency ◽

Cyclic Electron Flow ◽

Photochemical Quenching ◽

Photochemical Efficiency Of Psii ◽

High Level ◽

Non Photochemical Quenching ◽

Related Proteins

AbstractWhen plants suffer from abiotic stresses, cyclic electron flow (CEF) is induced for photoprotection. Putrescine (Put), a main polyamine in chloroplasts, plays a critical role in stress tolerance. To elucidate the mechanism of Put regulating CEF for salt-tolerance in cucumber leaves, we measured chlorophyll fluorescence, P700 redox state, ATP and NADPH accumulation and so on. The maximum photochemical efficiency of PSII (Fv/Fm) was not influenced by NaCl and/or Put, but the activity of PSI reaction center (P700) was seriously inhibited by NaCl. Salt stress induced high level of CEF, moreover, NaCl and Put treated plants exhibited much higher CEF activity and ATP accumulation than single salt-treated plants to provide adequate ATP/NADPH ratio for plants growth. Furthermore, Put decreased the trans-membrane proton gradient (ΔpH), accompanied by reducing the pH-dependent non-photochemical quenching (qE) and increasing efficient quantum yield of PSII (Y(II)). The ratio of NADP+/NADPH in salt stressed leaves was significantly increased by Put, indicating that Put relieved over-reduction pressure at PSI accepter side. Taken together, our results suggest that exogenous Put enhances CEF to supply extra ATP for PSI recovery and CO2 assimilation, decreases ΔpH for electron transport related proteins staying active, and enable the non-photochemical quenching transformed into photochemical quenching.

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