Chen Xiongwen, Gao Kunshan
Department of Biology, Hubei Normal University, Huangshi 435002, Hubei, China. Corresponding author; email:
Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, Hubei, China. Marine Biology Institute, Shantou University, Shantou 515063, Guangdong, China.
Funct Plant Biol. 2004 May;31(4):399-404. doi: 10.1071/FP03240.
Photosynthetic performance was examined in Skeletonema costatum (Greville) Cleve. under 12 : 12-h light : dark (LD) cycle at ambient CO (350 μL L) and elevated CO (1000 μL L). At ambient CO, the cellular chlorophyll a content, the light-saturated photosynthetic rate (P), the initial slope of the light saturation curves (α), the photochemical efficiency of PSII (F / F), the apparent carboxylating efficiency (ACE) and the photosynthetic affinity for CO [1 / K(CO)] all showed rhythmical changes with different amplitudes during the light period. The P had similar changing pattern in the light period with the ACE and 1 / K(CO) rather than with the α and F / F, indicating that rhythmical changes of photosynthetic capacity may be mainly controlled by the activity of C-reduction associated with CO uptake during the light period. The CO enrichment reduced the ACE and the affinity to CO, and increased the α, cellular chlorophyll a content and P based on cell number. By contrast, the changing patterns of all photosynthetic parameters examined here during the light period had almost the same for cells grown at ambient CO and elevated CO, suggesting that the photosynthetic rhythms of S. costatum are not affected by CO enrichment.
在环境CO₂（350 μL/L）和高浓度CO₂（1000 μL/L）条件下，于12:12小时光暗（LD）循环中检测了中肋骨条藻（Skeletonema costatum (Greville) Cleve.）的光合性能。在环境CO₂条件下，细胞叶绿素a含量、光饱和光合速率（P）、光饱和曲线的初始斜率（α）、PSII的光化学效率（Fv/Fm）、表观羧化效率（ACE）以及对CO₂的光合亲和力[1/K(CO₂)]在光照期间均呈现出不同幅度的节律性变化。P在光照期间的变化模式与ACE和1/K(CO₂)相似，而非与α和Fv/Fm相似，这表明光合能力的节律性变化可能主要受光照期间与CO₂吸收相关的C还原活性控制。CO₂富集降低了ACE和对CO₂的亲和力，并基于细胞数量增加了α、细胞叶绿素a含量和P。相比之下，这里检测的所有光合参数在光照期间对于在环境CO₂和高浓度CO₂条件下生长的细胞几乎具有相同的变化模式，这表明中肋骨条藻的光合节律不受CO₂富集的影响。
