Lessons from relatives: C4 photosynthesis enhances CO2 assimilation during the low-light phase of fluctuations.
Lessons from relatives: C4 photosynthesis enhances CO2 assimilation during the low-light phase of fluctuations.
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DOI：
10.1093/plphys/kiad355
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发表时间：
2023-09-22
期刊：
影响因子：
7.4
通讯作者：
Kromdijk, Johannes
中科院分区：
文献类型：
--
作者：
Cubas, Lucia Arce;Sales, Cristina Rodrigues Gabriel;Vath, Richard L.;Bernardo, Emmanuel L.;Burnett, Angela C.;Kromdijk, Johannes
尽管具有C4光合作用的物种具有全球重要性，但对于C4在波动光下的表现缺乏共识。相反的假设和实验证据表明，在波动的光照下，C4光合作用在固定碳方面的效率低于或高于祖先的C3形式。已确定的两个主要问题可能是缺乏共识：忽视了选定的C3和C4物种之间的进化距离，以及使用对比波动的光处理。为了绕过这些问题，我们测量了3个独立的系统发育对照的C3和C4种在21%和2%O2下对波动光的光合作用响应。叶片受到重复的逐级光强变化(800umolm−2 S−1光子通量密度)，有3个对比时间：6，30和300 S。这些实验与以往研究中发现的相反的结果相一致，表明：(1)C4物种在弱光阶段对二氧化碳同化的刺激比C3物种更强和更持久；(2)强光阶段的二氧化碳同化模式可能是由于物种或C4亚型的差异，而不是光合作用途径；(3)波动机制中每个光步的持续时间可以强烈地影响实验结果。比较了3种不同光照条件下C3和C4近缘种间的光合作用，发现C4光合作用在弱光条件下具有系统优势。
Despite the global importance of species with C4 photosynthesis, there is a lack of consensus regarding C4 performance under fluctuating light. Contrasting hypotheses and experimental evidence suggest that C4 photosynthesis is either less or more efficient in fixing carbon under fluctuating light than the ancestral C3 form. Two main issues have been identified that may underly the lack of consensus: neglect of evolutionary distance between selected C3 and C4 species and use of contrasting fluctuating light treatments. To circumvent these issues, we measured photosynthetic responses to fluctuating light across 3 independent phylogenetically controlled comparisons between C3 and C4 species from Alloteropsis, Flaveria, and Cleome genera under 21% and 2% O2. Leaves were subjected to repetitive stepwise changes in light intensity (800 and 100 µmol m−2 s−1 photon flux density) with 3 contrasting durations: 6, 30, and 300 s. These experiments reconciled the opposing results found across previous studies and showed that (i) stimulation of CO2 assimilation in C4 species during the low-light phase was both stronger and more sustained than in C3 species; (ii) CO2 assimilation patterns during the high-light phase could be attributable to species or C4 subtype differences rather than photosynthetic pathway; and (iii) the duration of each light step in the fluctuation regime can strongly influence experimental outcomes. Comparing photosynthesis in 3 pairs of closely related C3 and C4 species across 3 fluctuating light regimes shows that C4 photosynthesis has a systematic advantage under the low-light phase.
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影响因子：
7.4
作者：
KRALL, JP;PEARCY, RW
通讯作者：
PEARCY, RW
影响因子：
7.3
作者：
Kromdijk, Johannes;Griffiths, Howard;Schepers, Hans E.
通讯作者：
Schepers, Hans E.
DOI：
10.1071/pp97002
发表时间：
1997-01-01
期刊：
AUSTRALIAN JOURNAL OF PLANT PHYSIOLOGY
影响因子：
--
作者：
Laisk, A;Edwards, GE
通讯作者：
Edwards, GE
影响因子：
5.6
作者：
Cubas, Lucia Arce;Vath, Richard L.;Bernardo, Emmanuel L.;Sales, Cristina Rodrigues Gabriel;Burnett, Angela C.;Kromdijk, Johannes
通讯作者：
Kromdijk, Johannes
影响因子：
6.9
作者：
Arrivault S;Obata T;Szecówka M;Mengin V;Guenther M;Hoehne M;Fernie AR;Stitt M
通讯作者：
Stitt M