Does growth under elevated CO2 moderate photoacclimation in rice?
Does growth under elevated CO2 moderate photoacclimation in rice?
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DOI：
10.1111/j.1399-3054.2012.01702.x
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发表时间：
2013-06-01
影响因子：
6.4
通讯作者：
Murchie, Erik H.
中科院分区：
文献类型：
--
作者：
Hubbart, Stella;Bird, Susannah;Murchie, Erik H.
植物光合作用对光照的适应（光适应）涉及色素和蛋白质水平的调节以及叶片形态的较大尺度变化。为了研究大气CO2浓度升高对作物生理的影响，我们假设大气CO2浓度升高与水稻的光适应相互作用。水稻在强光（HL：700 μ molm 2s-1）、弱光（LL：200 μ molm 2s-1）、环境CO2（400 μ mol-1）和升高的CO2（1000 μ mol-1）下生长。叶六是全程测量。在发育过程中不明显的分生组织并没有改变叶片厚度，表明成熟叶片在光适应过程中负责感光。CO2浓度升高提高生长室光合作用和增加分蘖形成在两个光水平，而它增加叶长下LL，但不下HL。CO2浓度升高总是导致叶片生长速率和分蘖产量增加。叶片厚度、叶面积、Rubisco含量、茎叶淀粉、蔗糖和果糖含量的变化均受光照的控制，不受CO2的影响。然而，气孔响应不同，他们是显着较小的LL生长的植物相比，HL，但这种效果显着抑制CO2浓度升高。气孔密度较低LL下，但这需要升高CO2和幅度是近轴或背轴表面依赖。我们的结论是，水稻的光适应涉及一个系统信号。此外，额外的碳水化合物在CO2浓度升高下产生的利用，在提高叶片和分蘖生长，并不增强或抑制任何功能的光适应与气孔形态。
Acclimation of plant photosynthesis to light irradiance (photoacclimation) involves adjustments in levels of pigments and proteins and larger scale changes in leaf morphology. To investigate the impact of rising atmospheric CO2 on crop physiology, we hypothesize that elevated CO2 interacts with photoacclimation in rice (Oryza sativa). Rice was grown under high light (HL: 700 mu molm2s1), low light (LL: 200 mu molm2s1), ambient CO2 (400 mu ll1) and elevated CO2 (1000 mu ll1). Leaf six was measured throughout. Obscuring meristem tissue during development did not alter leaf thickness indicating that mature leaves are responsible for sensing light during photoacclimation. Elevated CO2 raised growth chamber photosynthesis and increased tiller formation at both light levels, while it increased leaf length under LL but not under HL. Elevated CO2 always resulted in increased leaf growth rate and tiller production. Changes in leaf thickness, leaf area, Rubisco content, stem and leaf starch, sucrose and fructose content were all dominated by irradiance and unaffected by CO2. However, stomata responded differently; they were significantly smaller in LL grown plants compared to HL but this effect was significantly suppressed under elevated CO2. Stomatal density was lower under LL, but this required elevated CO2 and the magnitude was adaxial or abaxial surface-dependent. We conclude that photoacclimation in rice involves a systemic signal. Furthermore, extra carbohydrate produced under elevated CO2 is utilized in enhancing leaf and tiller growth and does not enhance or inhibit any feature of photoacclimation with the exception of stomatal morphology.