TY - CHAP
T1 - Gradients of photoinhibition in the interior of a leaf induced by photoinhibition lights of different colors
AU - Oguchi, Riichi
AU - Douwstra, Peter
AU - Fujita, Takashi
AU - Chow, Wah Soon
AU - Terashima, Ichiro
N1 - Funding Information:
We thank H Abe for his generous offer of instruments, S Syu for his supporting plants growth, R Nakane for his experimental support and advice, Y Wang for her experimental support and Jan for her helpful comments on the manuscript. This work was supported by JSPS Research Fellowship for Young Scientists (18-8553 to R O); JSPS Postdoctoral Fellowships for Research Abroad (21-674 to R O); an Australian Research Council (DP1093827 to W S C); and Grant-in-Aid for Challenging Exploratory Research (21657007 to I T).
Publisher Copyright:
© Zhejiang University Press, Hangzhou and Springer-Verlag Berlin Heidelberg 2013.
PY - 2013
Y1 - 2013
N2 - Gradients of photoinhibition within a leaf caused by different color lights were studied to get more insight into the controversy whether photon absorption by chlorophyll or Mn is the primary cause of photoinhibition, suggested by the excess-energy hypothesis or the Mn (two-step) hypothesis, respectively. We photoinhibited lincomycin-treated leaf-discs with white, blue, green or red light. A combination of a micro-fiber fluorometer, a fiber-thinning technique and a micro-manipulator enabled us to measure the chlorophyll fluorescence signals within a leaf. Gradients of photoinhibition were also compared with results from various conventional fluorometers to estimate their depth of signal detection. The photoinhibition was more severe in the descending order of blue, red and green light near the adaxial surface, and in the descending order of blue, green and red light in the deeper tissue, which is correlated with the absorption spectrum of chlorophyll and Mn, respectively. These results cannot be explained by either hypothesis alone and strongly suggest that both mechanisms occur in photoinhibition. Fv/Fm values of photoinhibited leaves estimated with the conventional fluorometers were different from the whole tissue. This is because the depths, in which these systems detect fluorescence signals, differ depending on the wavelengths of measuring beam and detector.
AB - Gradients of photoinhibition within a leaf caused by different color lights were studied to get more insight into the controversy whether photon absorption by chlorophyll or Mn is the primary cause of photoinhibition, suggested by the excess-energy hypothesis or the Mn (two-step) hypothesis, respectively. We photoinhibited lincomycin-treated leaf-discs with white, blue, green or red light. A combination of a micro-fiber fluorometer, a fiber-thinning technique and a micro-manipulator enabled us to measure the chlorophyll fluorescence signals within a leaf. Gradients of photoinhibition were also compared with results from various conventional fluorometers to estimate their depth of signal detection. The photoinhibition was more severe in the descending order of blue, red and green light near the adaxial surface, and in the descending order of blue, green and red light in the deeper tissue, which is correlated with the absorption spectrum of chlorophyll and Mn, respectively. These results cannot be explained by either hypothesis alone and strongly suggest that both mechanisms occur in photoinhibition. Fv/Fm values of photoinhibited leaves estimated with the conventional fluorometers were different from the whole tissue. This is because the depths, in which these systems detect fluorescence signals, differ depending on the wavelengths of measuring beam and detector.
KW - Chlorophyll fluorescence
KW - Excess-energy hypothesis
KW - Fluorometers
KW - Mn hypothesis
KW - P700 redox kinetics
KW - Photoinhibition action spectra
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U2 - 10.1007/978-3-642-32034-7_96
DO - 10.1007/978-3-642-32034-7_96
M3 - Chapter
AN - SCOPUS:85027161147
T3 - Advanced Topics in Science and Technology in China
SP - 459
EP - 464
BT - Advanced Topics in Science and Technology in China
PB - Springer Science and Business Media Deutschland GmbH
ER -