Abstract

While the general effect of CO₂ enrichment on photosynthesis, stomatal conductance, N content, and yield has been documented, there is still some uncertainty as to whether there are interactive effects between CO₂ enrichment and other factors, such as temperature, geographical location, water availability, and cultivar. In addition, the metabolic coordination between leaves and grains, which is crucial for crop responsiveness to elevated CO₂, has never been examined closely. Here, we address these two aspects by multi-level analyses of data from several free-air CO₂ enrichment experiments conducted in five different countries. There was little effect of elevated CO₂ on yield (except in the USA), likely due to photosynthetic capacity acclimation, as reflected by protein profiles. In addition, there was a significant decrease in leaf amino acids (threonine) and macroelements (e.g. K) at elevated CO₂, while other elements, such as Mg or S, increased. Despite the non-significant effect of CO₂ enrichment on yield, grains appeared to be significantly depleted in N (as expected), but also in threonine, the S-containing amino acid methionine, and Mg. Overall, our results suggest a strong detrimental effect of CO₂ enrichment on nutrient availability and remobilization from leaves to grains.

中文翻译：

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尽管对产量的影响微乎其微，但二氧化碳浓度升高却同时对小麦的叶片和籽粒代谢产生影响。

摘要

_{虽然CO 2}富集对光合作用、气孔导度、氮含量和产量的一般影响已被记录，但CO ₂富集与其他因素（例如温度、地理位置、水的可用性和品种。此外，叶子和谷物之间的代谢协调对于作物对CO ₂升高的反应至关重要，但从未得到过仔细研究。在这里，我们通过对在五个不同国家进行的几个自由空气 CO ₂浓缩实验的数据进行多层次分析来解决这两方面的问题。_{CO 2}升高对产量几乎没有影响（美国除外），这可能是由于光合能力驯化所致，如蛋白质谱所反映的那样。_{此外，在CO 2}升高时，叶氨基酸（苏氨酸）和常量元素（例如K）显着减少，而其他元素，例如Mg或S则增加。_{尽管CO 2}富集对产量的影响并不显着，但谷物中的氮含量似乎显着减少（如预期），而且苏氨酸、含硫氨基酸蛋氨酸和镁含量也明显减少。总体而言，我们的结果表明，CO ₂富集对养分可用性和从叶子到谷物的再利用具有强烈的不利影响。