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Christov, I. K.; Stefanov, D.; Goltsev, V.; Abrasheva, P.

doi:10.1023/a:1016799329371

Cited by 11 publications

(1 citation statement)

References 11 publications

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“…Using a suitable experimental approach, DF may be used for the analysis of the effect of chemical and physical factors: high and low temperatures (2,11,13,36); light stress (31) and UV irradiation (31,40), drought and high salinity (21,38), herbicides (17), heavy metals (22), harmful gasses (6). The millisecond DF is sensitive to plant diseases which are a result of viral and bacterial infections (16,20), and even to changes in the physiological state of the plant cell during its ontogenetic development, greening and different hormonal levels (27,35,39).…”

Section: Mechanisms Of Delayed Fluorescencementioning

confidence: 99%

Delayed Chlorophyll Fluorescence as a Monitor for Physiological State of Photosynthetic Apparatus

Goltsev

Zaharieva

Chernev

et al. 2009

Biotechnology & Biotechnological Equipment

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Intact plants emit light quanta called delayed fluorescence (DF). DF is result of radiative deactivation of secondary excited chlorophyll molecules in Photosystem II (PS II) antennae complexes. The excitations are produced by backward electrontransfer reactions both in the donor and acceptor sides of PS II. The poly-exponential dark decay of DF in a time interval of tens of nanoseconds to tens of seconds reflects the kinetics of different forward and backward reactions of the photosynthetic electron transfer. The current work reviews the mechanisms of the DF light quanta generation and the methodical approaches that allow us to obtain quantitative information about the photosynthetic machinery state using the DF signal from native objects. We examine an approach for the simultaneous record of DF and prompt chlorophyll fluorescence during the transition of the photosynthetic machinery from dark-adapted to light-adapted state. A new device (Senior PEA) built by Hansatech (King's Lynn, UK) allows us to measure simultaneously the induction transients of prompt chlorophyll fluorescence, DF decaying in a time range 10 µs-240 ms, and the changes in transmission at 820 nm. The comparative analysis of the three types of signals and the application of a model-based description of the processes and reactions that determine the dynamics of the signals during the light-induced transitions (dynamic models and JIP-test) allow us to obtain, from a single few-seconds-long measurement, quantitative information for: a) energetic fluxes and efficiencies at different steps of energy transformation; b) rate constants of electron transfer in and between the two photosystems; c) energization of the thylakoid membrane. This illustrates that DF in combination with other optical and luminescent measurements is a highly informative method for investigation of the physiological state of the photosynthetic apparatus of plants in vivo and in situ, and is an indispensable tool for the purposes of the biophysical phenomics.

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Section: Mechanisms Of Delayed Fluorescencementioning

confidence: 99%

Delayed Chlorophyll Fluorescence as a Monitor for Physiological State of Photosynthetic Apparatus

Goltsev

Zaharieva

Chernev

et al. 2009

Biotechnology & Biotechnological Equipment

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Delayed fluorescence in photosynthesis

et al. 2009

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Photosynthesis is a very efficient photochemical process. Nevertheless, plants emit some of the absorbed energy as light quanta. This luminescence is emitted, predominantly, by excited chlorophyll a molecules in the light-harvesting antenna, associated with Photosystem II (PS II) reaction centers. The emission that occurs before the utilization of the excitation energy in the primary photochemical reaction is called prompt fluorescence. Light emission can also be observed from repopulated excited chlorophylls as a result of recombination of the charge pairs. In this case, some time-dependent redox reactions occur before the excitation of the chlorophyll. This delays the light emission and provides the name for this phenomenon-delayed fluorescence (DF), or delayed light emission (DLE). The DF intensity is a decreasing polyphasic function of the time after illumination, which reflects the kinetics of electron transport reactions both on the (electron) donor and the (electron) acceptor sides of PS II. Two main experimental approaches are used for DF measurements: (a) recording of the DF decay in the dark after a single turnover flash or after continuous light excitation and (b) recording of the DF intensity during light adaptation of the photosynthesizing samples (induction curves), following a period of darkness. In this paper we review historical data on DF research and recent advances in the understanding of the relation between the delayed fluorescence and specific reactions in PS II. An experimental method for simultaneous recording of the induction transients of prompt and delayed chlorophyll fluorescence and decay curves of DF in the millisecond time domain is discussed.

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Accelerated leaf senescence takes part in enhanced resistance in cucumber mosaic virus inoculated pepper leaves

et al. 2011

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Altered photosynthetic reactions in cucumber mosaic virus (CMV) inoculated leaves of virus resistant lines L113 and L57 and susceptible pepper (Capsicum annuum L.) plants cv. Albena grown in controlled environment and in the field were investigated. The CMV inoculated leaves of virus resistant lines developed different symptoms-necrotic local lesions on L113 and chlorotic spots on L57 while the same leaves of susceptible cv. Albena were symptomless. The changes in Photosystem II (PSII) and PSI electron transport were evaluated by chlorophyll fluorescence, and far-red (FR) light induced leaf absorbance A 810-860 . CMV infection caused a decrease in maximal PSII quantum yield, F v /F m , in susceptible leaves. Increased non-photochemical fluorescence quenching in CMV-inoculated leaves of both resistant lines were observed. In CMV-inoculated leaves of all tested plants FR light induced P700 oxidation was decreased. In the present study, the viral-infected pepper plants grown in controlled environment to avoid the effects of abiotic factors were used as model system that allow us to investigate the differences in leaf senescence in CMV-inoculated leaves of susceptible and resistant pepper lines expressing different symptoms. Earlier leaf falls of inoculated leaves as a result of accelerated leaf senescence is important for building successful secondary virus resistance strategy following fast responses such as hypersensitive reaction.

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Untitled

Cited by 11 publications

References 11 publications

Delayed Chlorophyll Fluorescence as a Monitor for Physiological State of Photosynthetic Apparatus

Delayed Chlorophyll Fluorescence as a Monitor for Physiological State of Photosynthetic Apparatus

Delayed fluorescence in photosynthesis

Accelerated leaf senescence takes part in enhanced resistance in cucumber mosaic virus inoculated pepper leaves

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