TY  - JOUR
AU  - Acebron, Kelvin
AU  - Matsubara, Shizue
AU  - Jedmowski, Christoph
AU  - Emin, Dzhaner
AU  - Muller, Onno
AU  - Rascher, Uwe
TI  - Diurnal dynamics of non‐photochemical quenching in Arabidopsis npq mutants assessed by solar‐induced fluorescence and reflectance measurements in the field
JO  - The new phytologist
VL  - 229
IS  - 4
SN  - 1469-8137
CY  - Oxford [u.a.]
PB  - Wiley-Blackwell
M1  - FZJ-2020-03849
SP  - 2104-2119
PY  - 2021
AB  - Solar‐induced fluorescence (SIF) is highly relevant in mapping photosynthesis from remote‐sensing platforms. This requires linking SIF to photosynthesis and understanding the role of nonphotochemical quenching (NPQ) mechanisms under field conditions. Hence, active and passive fluorescence were measured in Arabidopsis with altered NPQ in outdoor conditions.    Plants with mutations in either violaxanthin de‐epoxidase (npq1) or PsbS protein (npq4) exhibited reduced NPQ capacity. Parallel measurements of NPQ, photosystem II efficiency, SIF and spectral reflectance (ρ) were conducted diurnally on one sunny summer day and two consecutive days during a simulated cold spell.    Results showed that both npq mutants exhibited higher levels of SIF compared to wild‐type plants. Changes in reflectance were related to changes in the violaxanthin–antheraxanthin–zeaxanthin cycle and not to PsbS‐mediated conformational changes. When plants were exposed to cold temperatures, rapid onset of photoinhibition strongly quenched SIF in all lines.    Using well‐characterized Arabidopsis npq mutants, we showed for the first time the quantitative link between SIF, photosynthetic efficiency, NPQ components and leaf reflectance. We discuss the functional potential and limitations of SIF and reflectance measurements for estimating photosynthetic efficiency and NPQ in the field.
LB  - PUB:(DE-HGF)16
C6  - 33020945
UR  - <Go to ISI:>//WOS:000584802700001
DO  - DOI:10.1111/nph.16984
UR  - https://juser.fz-juelich.de/record/885466
ER  -