Rae A M, Ferris Rachel, Tallis M J, Taylor Gail
School of Biological Sciences, University of Southampton, Bassett Crescent East, Southampton, UK.
Plant Cell Environ. 2006 Sep;29(9):1730-41. doi: 10.1111/j.1365-3040.2006.01545.x.
Limited information is available on the genetic variation and control for plant growth response to elevated CO(2) (e[CO(2)]). Such information is necessary to understand plant adaptation and evolution in future rising CO(2). Here, quantitative trait loci (QTL) for leaf growth, development, quality and leaf senescence were determined in a tree pedigree - an F(2) hybrid of Populus trichocarpa T. & G and Populus deltoides Marsh, following season-long exposure to either current day ambient carbon dioxide (a[CO(2)]) or e[CO(2)] at 600 microL L(-1). Leaf growth and development differed between the grandparents such that P. trichocarpa showed greater response to e[CO(2)]. In the F(2) generation, leaf development and quality traits including leaf area, leaf shape, epidermal cell area, and stomatal number, specific leaf area (SLA), and the phenology trait, canopy senescence index, were sensitive to e[CO(2)]. Sixty-nine QTL were mapped for the 19 traits of plants in a[CO(2)] while 60 QTL were mapped for plants in e[CO(2)]. The results suggest that although many QTL mapped to common positions in a[CO(2)] and e[CO(2)], confirming their importance in determining growth, there was also differential genetic control for a number of traits including leaf senescence. Candidate genes were shown to collocate to regions where response QTL mapped. This study is the first to identify candidate genes that may be important in determining plant adaptation to future high-CO(2) world.
关于植物对高浓度二氧化碳（e[CO₂]）生长响应的遗传变异和控制的信息有限。这些信息对于理解未来二氧化碳浓度升高时植物的适应和进化是必要的。在此，在一个树木谱系——毛果杨（Populus trichocarpa T. & G）和三角叶杨（Populus deltoides Marsh）的F₂杂种中，测定了叶片生长、发育、质量和叶片衰老的数量性状位点（QTL），该谱系在整个生长季暴露于当前环境二氧化碳浓度（a[CO₂]）或600 μL L⁻¹的e[CO₂]环境中。祖父母本之间的叶片生长和发育存在差异，使得毛果杨对e[CO₂]的响应更大。在F₂代中，叶片发育和质量性状，包括叶面积、叶形、表皮细胞面积、气孔数量、比叶面积（SLA）以及物候性状——冠层衰老指数，对e[CO₂]敏感。在a[CO₂]环境下，针对植物的19个性状定位了69个QTL，而在e[CO₂]环境下针对植物定位了60个QTL。结果表明，尽管许多QTL在a[CO₂]和e[CO₂]环境下映射到相同位置，证实了它们在决定生长方面的重要性，但对于包括叶片衰老在内的一些性状也存在差异遗传控制。候选基因显示与响应QTL映射的区域共定位。这项研究首次鉴定出可能在决定植物适应未来高二氧化碳世界方面很重要的候选基因。
