以高大气CO₂浓度和遮阴为处理手段，研究高大气CO₂浓度和遮阴对小麦叶片光合生理的影响。结果表明，与全光照相比，遮阴使小麦叶片的气孔长度增加了22.93%和10.23%，而气孔宽度减小了30.00%和30.22%，气孔面积降低了17.99%和18.11%，周长增加了16.80%和6.85%，气孔密度降低了6.61%和23.78%，气孔指数降低了5.99%和14.23%。与正常大气CO₂浓度相比，高大气CO₂浓度使小麦叶片的气孔面积增加了1.91%和1.95%，使全光照处理的小麦叶片的气孔密度降低了14.33%；使遮阴处理的小麦叶片的气孔密度增加了5.00%。与全光照相比，遮阴使小麦叶片的气孔导度和蒸腾速率降低了56.11%、53.21%和40.57%、49.27%，而光合速率没有得到提高，这可能是小麦叶片对高大气CO₂浓度发生了“光适应”。与正常大气CO₂浓度相比，高大气CO₂浓度降低了小麦叶片的气孔导度。小麦叶片的气孔长度和宽度与光合速率有显著相关性。

Effects of shading and elevated atmospheric CO₂ concentration on leaf photosynthetic physiology are investigated using shading and elevated atmospheric CO₂ concentration treatments. The result shows that compared with normal sunlight condition， shading treatments increased stomata length by 22.93% and 10.23%， decreased stomata width by 30.00% and 30.22%， decreased stomatal area by 17.99% and 18.11%， increased circumference by 16.80% and 6.85%， decreased stomata density by 6.61% and 23.78%， and decreased stomatal index by 5.99% and 14.23%， under normal and elevated atmospheric CO₂ concentration， respectively. Compared with normal atmospheric CO₂ concentration， elevated atmospheric CO₂ concentration increased stomatal area by 1.91% and 1.95%， decreased stomata density by 14.33% under sunlight condition while increased by 5.00% with shading treatment. Compared with sunlight condition， shading decreased stomatal conductance by 56.11% and 53.21% and transpiration rate by 40.57% and 49.27% under normal and elevated CO₂ concentration， respectively. However， the treatments have no effects on photosynthetic rate， which is probably due to the occurrence of “light adaptation” under elevated CO₂ concentration. Compared with normal atmospheric CO₂ concentration， elevated CO₂ concentration decreased stomatal conductance of wheat. Leaf pore length and blades width of wheat are significantly correlated with the rate of photosynthesis.

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国家自然基金“高大气CO₂浓度下蚕豆叶片内源NO对气孔行为的调节及其氮素响应”(31160090)；国家自然基金“小麦叶片光合能量转化对长期高大气CO₂浓度的反馈机制及其氮素调控”(30800668)；甘肃省重大专项“甘肃中东部粮食作物稳产增效技术集成示范”(1502NKDA003)。