Plant Evolution at Elevated CO2: Physiological and Genetic Mechanisms Controlling Developmental Timing

植物在高[二氧化碳]下的进化：控制发育时间的生理和遗传机制乔伊·K·沃德(PI)，堪萨斯大学生态和进化生物学系约翰·K·凯利(Co-PI)，堪萨斯大学生态和进化生物学系拟议的研究目的是确定大气二氧化碳升高对田间采集的和选定的拟南芥基因型的发育时间的影响，并阐明控制这一反应的遗传和分子机制。全球变化因素将对未来陆地生态系统的功能和生产力产生深远影响。与不同地区的温度和降水不同，大气中的二氧化碳在全球范围内正在上升，并为植物创造了新的碳可获得性水平。确定植物对不断上升的二氧化碳的适应机制并了解这些反应将如何影响植物未来的功能和生产力是至关重要的。植物对二氧化碳升高的反应时间的变化可能会决定快速变化的环境中的长期进化过程，但这些反应相对较少受到关注。为了解决这个问题，已经选择了特定的拟南芥遗传系，以在预计未来70-100年内二氧化碳浓度升高的情况下提高种子产量。当生长在较高的二氧化碳浓度(700ppm)和当前的二氧化碳浓度(380ppm)时，对选择有明显反应的品系表现出开花的时间中断，而随机选择的对照基因型不表现出这种反应。这代表了一种前所未有的系统，可以在进化相关的背景下研究植物对二氧化碳升高的发育反应。本研究的目标如下：(1)确定二氧化碳浓度升高对来自北美和欧洲不同地区的拟南芥植株开花时间的影响；(2)确定在二氧化碳浓度升高时表现优异的拟南芥基因型的延迟开花的染色体区域；(3)鉴定在二氧化碳浓度升高时影响开花时间的基因的作用。拟议的研究具有高度跨学科的性质，因此在分子生物学、数量遗传学和生理生态学领域提供了极好的培训机会。该项目将包括代表性不足的群体的参与，包括哈斯克尔印第安人国家大学的学生和堪萨斯大学生物科学倡议项目的学生，该项目增加了少数群体在生物科学领域的代表性。最后，这项研究将通过开发遗传植物资源使科学界受益，这些资源将提供给其他有兴趣了解植物如何适应未来大气二氧化碳浓度上升的研究人员。

Plant Evolution at Elevated [CO2]: Physiological and Genetic Mechanisms Controlling Developmental TimingJoy K. Ward (PI), University of Kansas, Department of Ecology and Evolutionary BiologyJohn K. Kelly (Co-PI), University of Kansas, Department of Ecology and Evolutionary BiologyThe purpose of the proposed research is to determine the effects of elevated atmospheric carbon dioxide on the developmental timing of field-collected and selected genotypes of Arabidopsis thaliana and to elucidate the genetic and molecular mechanisms that control this response. Global change factors will have profound effects on the functioning and productivity of terrestrial ecosystems in the future. Unlike temperature and precipitation that vary across regions, atmospheric carbon dioxide is rising on a global scale and is producing novel levels of carbon availability for plants. It is critical to define the mechanisms for plant adaptation to rising carbon dioxide and to understand how these responses will influence plant functioning and productivity in the future. Changes in the developmental timing of plants in response to elevated carbon dioxide are likely to dictate long-term evolutionary processes in a rapidly changing environment, yet these responses have received relatively little attention. To address this issue, specific genetic lines of Arabidopsis have been selected for increased seed production at elevated carbon dioxide predicted for 70-100 years in the future. Lines showing pronounced responses to selection exhibit disruptions in time to flowering when grown at elevated (700 ppm) versus current (380 ppm) carbon dioxide concentrations, whereas randomly selected control genotypes do not exhibit this response. This represents an unprecedented system for studying the developmental responses of plants to elevated carbon dioxide in an evolutionarily relevant context. This research addresses the following objectives: (1) to determine the effects of elevated carbon dioxide on time to flowering for Arabidopsis plants from different locations throughout North America and Europe, (2) to identify chromosomal regions that confer delayed flowering for an Arabidopsis genotype that was selected for high performance at elevated carbon dioxide, and (3) to characterize the effects of genes that influence the timing of flowering at elevated carbon dioxide. The proposed research is highly inter-disciplinary in nature, and therefore offers excellent training opportunities in the fields of molecular biology, quantitative genetics, and physiological ecology. This project will include the participation of under-represented groups, including students from Haskell Indian Nations University and from the Bioscience Initiative program at the University of Kansas that increases the representation of minorities in the biological sciences. Finally, this research will benefit the scientific community through the development of genetic plant resources that will be made available to other researchers interested in understanding how plants will adapt to rising concentrations of atmospheric carbon dioxide in the future.