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

CO2浓度升高时植物的进化：控制发育时间的生理和遗传机制。沃德（PI），堪萨斯大学，生态学和进化生物学系。Kelly（Co-PI），堪萨斯大学生态学与进化生物学系这项研究的目的是确定大气二氧化碳浓度升高对田间采集和选择的拟南芥基因型发育时间的影响，并阐明控制这种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量不同，大气中的二氧化碳在全球范围内正在上升，并为植物提供了新的碳供应水平。关键是要确定植物适应二氧化碳上升的机制，并了解这些反应将如何影响植物功能和生产力的未来。在快速变化的环境中，植物对二氧化碳浓度升高的反应可能决定长期的进化过程，但这些反应相对较少受到关注。为了解决这个问题，选择了拟南芥的特定遗传品系，以在预测未来70-100年的二氧化碳浓度升高的情况下增加种子产量。显示出明显的选择反应的线表现出中断的时间开花时，生长在升高（700 ppm）与当前（380 ppm）的二氧化碳浓度，而随机选择的对照基因型不表现出这种反应。这是一个前所未有的系统，用于研究植物在进化相关背景下对二氧化碳浓度升高的发育反应。这项研究涉及以下目标：（1）确定升高的二氧化碳对来自整个北美和欧洲不同地点的拟南芥植物开花时间的影响，（2）鉴定赋予拟南芥基因型延迟开花的染色体区域，所述拟南芥基因型被选择用于在升高的二氧化碳下的高性能，和（3）表征影响二氧化碳浓度升高时开花时间的基因的作用。拟议的研究是高度跨学科的性质，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。这一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民族大学的学生和来自堪萨斯大学生物科学倡议方案的学生，该方案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.