Abstract Variation in atmospheric carbon dioxide (CO2) concentration can dictate plant growth and development and shape plant evolution. For paired populations of 31 Arabidopsis accessions, respectively, grown under 100 or 380 ppm CO2, we compared phenotypic traits related to vegetative growth and flowering time. Four accessions showed the least variation in measured growth traits between 100 ppm CO2 and 380 ppm CO2 conditions, though all accessions exhibited a dwarf stature with reduced biomass under low CO2. Our comparison of accessions also incorporated the altitude (indicated in meters) above sea level at which they were originally collected. Notably, An-1 (50 m), Est (50 m), Ws-0 (150 m), and Ler-0 (600 m) showed the least differences (lower decrease or increase) between treatments in flowering time, rosette leaf number, specific leaf weight, stomatal density, and less negative δ13C values. When variations for all traits and seedset were considered together, Ws-0 exhibited the least change between treatments. Our results showed that physiological and phenotypic responses to low CO2 varied among these accessions and did not correlate linearly with altitude, thus suggesting that slower growth or smaller stature under ambient CO2 may potentially belie a fitness advantage for sustainable growth under low CO2 availability.

中文翻译：

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拟南芥低 CO2 诱导应激反应的自然变异

摘要 大气二氧化碳 (CO2) 浓度的变化可以决定植物的生长和发育并影响植物进化。对于分别在 100 或 380 ppm CO2 下生长的 31 个拟南芥种质的配对种群，我们比较了与营养生长和开花时间相关的表型性状。四个种质在 100 ppm CO2 和 380 ppm CO2 条件之间显示出测量的生长性状变化最小，尽管所有种质都表现出矮小身材，在低 CO2 下生物量减少。我们对种质的比较还包括它们最初收集时的海拔高度（以米表示）。值得注意的是，An-1 (50 m)、Est (50 m)、Ws-0 (150 m) 和 Ler-0 (600 m) 在开花时间、莲座叶数量，比叶重，气孔密度和较小的负 δ13C 值。当所有性状和种子集的变化一起考虑时，Ws-0 在处理之间表现出最小的变化。我们的结果表明，这些种质对低 CO2 的生理和表型响应各不相同，并且与海拔高度无关，因此表明在环境 CO2 下生长缓慢或身材矮小可能掩盖了在低 CO2 可用性下可持续生长的适应性优势。