TY - JOUR
T1 - The different roles of chilling temperatures in the photoinhibition of photosystem I and photosystem II
AU - Sonoike, Kintake
N1 - Funding Information:
I am grateful to Mr A. Aoyama for technical advice. This work was supported in part by research grants from the Human Frontier Science Program and from the Ministry of Education, Sciences, Sports and Culture, Japan.
PY - 1999/2
Y1 - 1999/2
N2 - The role of chilling temperatures on photoinhibition of photosystems I and II (PSI and PSII) under weak light has been examined in cucumber, a chilling-sensitive plant. The extent of PSII photoinhibition, determined by pulse-modulated fluorescence in vivo, is closely related to the redox state of the PSII electron acceptor Q(A), measured as a fluorescence parameter, 1 - q(p). On the other hand, the extent of PSI photoinhibition, which is only observed in chilling-sensitive plants at chilling temperatures, cannot be related to the redox state of Q(A), suggesting that the underlying mechanism is different from that of PSII photoinhibition. Chilling treatment at low photon flux densities is found to enhance cyclic electron flow around PSI. Both PSI photoinhibition and enhanced cyclic electron flow show similar temperature dependence, with the threshold temperature at 10°C.
AB - The role of chilling temperatures on photoinhibition of photosystems I and II (PSI and PSII) under weak light has been examined in cucumber, a chilling-sensitive plant. The extent of PSII photoinhibition, determined by pulse-modulated fluorescence in vivo, is closely related to the redox state of the PSII electron acceptor Q(A), measured as a fluorescence parameter, 1 - q(p). On the other hand, the extent of PSI photoinhibition, which is only observed in chilling-sensitive plants at chilling temperatures, cannot be related to the redox state of Q(A), suggesting that the underlying mechanism is different from that of PSII photoinhibition. Chilling treatment at low photon flux densities is found to enhance cyclic electron flow around PSI. Both PSI photoinhibition and enhanced cyclic electron flow show similar temperature dependence, with the threshold temperature at 10°C.
KW - Chilling damage
KW - Cyclic electron transfer
KW - Excitation pressure
KW - Photoinhibition
KW - Photosynthesis
KW - Photosystems I and II
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U2 - 10.1016/S1011-1344(99)00030-5
DO - 10.1016/S1011-1344(99)00030-5
M3 - Article
AN - SCOPUS:0033081606
SN - 1011-1344
VL - 48
SP - 136
EP - 141
JO - Journal of Photochemistry and Photobiology B: Biology
JF - Journal of Photochemistry and Photobiology B: Biology
IS - 2-3
ER -