Graduate School of Life Sciences, Tohoku University, Aoba, Sendai 980-8578, Japan.
Oecologia. 2011 Mar;165(3):809-18. doi: 10.1007/s00442-010-1900-1. Epub 2011 Jan 14.
The atmospheric CO(2) concentration [CO(2)] has been increasing markedly since the industrial revolution and is predicted to reach 500-1,000 μmol mol(-1) by the end of this century. Although the short-term and acclimatory responses to elevated [CO(2)] have been well studied, much less is understood about evolutionary responses to high [CO(2)]. We studied phenotypic and genetic differences in Plantago asiatica populations around a natural CO(2) spring, where [CO(2)] has been consistently high over an evolutionary time scale. Our common-garden experiment revealed that plants transferred from habitats with higher [CO(2)] had higher relative growth rates, greater leaf to root ratios, lower photosynthetic rates, and lower stomatal conductance. The habitat-dependent differences were partly heritable because a similar trend of leaf to root ratio was found among their offsprings. Genetic analyses indicated that selfing or biparental inbreeding might promote local adaptation in areas with high [CO(2)] despite substantial gene flow across the [CO(2)] gradient. These results indicate that phenotypic and genetic differences have occurred between high and normal [CO(2)] populations.
大气中二氧化碳（CO2）浓度自工业革命以来显著增加，预计本世纪末将达到 500-1000 μmol mol（-1）。尽管已经很好地研究了短期和适应高 CO2 的响应，但对于高 CO2 下的进化响应了解甚少。我们研究了围绕天然 CO2 泉的车前草种群的表型和遗传差异，该泉的 CO2 浓度在进化时间尺度上一直保持较高水平。我们的田间实验表明，从 CO2 浓度较高的生境转移的植物具有更高的相对生长率、更大的叶根比、更低的光合速率和更低的气孔导度。由于在它们的后代中发现了类似的叶根比趋势，因此生境依赖性差异部分具有遗传性。遗传分析表明，尽管存在跨越 CO2 梯度的大量基因流，但自交或双亲近亲繁殖可能会促进高 CO2 地区的局部适应。这些结果表明，高和正常 CO2 种群之间已经出现了表型和遗传差异。
