Interactive Effects of Temperature and CO2 Levels on C3 and C4 Plants

温度和二氧化碳水平对 C3 和 C4 植物的交互影响

• 批准号: 154273-2012
• 负责人: Sage, Rowan
• 金额: $ 2.91万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2012
• 资助国家: 加拿大
• 起止时间: 2012-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=506772
• 关键词: Interactive; Effects; Temperature; CO2; Levels

The proposed research will improve our understanding of photosynthesis in plants affected by high rates of photorespiration occurring in warm environments. Through this work, we intend to identify new ways to improve crop performance by reducing photorespiratory limitations and thus enhancing the photosynthetic capacity of C3 plants. We will evaluate how C3 plants compensate for high rates of photorespiration by (i) studying mechanisms enhancing intracellular refixation of photorespired CO2, and (ii) the early evolution of the C4 photosynthetic pathway. In the refixation project, we will evaluate whether the formation of chloroplast sheaths around the leaf cell periphery enhances the reassimilation of photorespired CO2. We will examine if chloroplast sheath formation is inducible under low CO2 and warm temperatures promoting photorespiration, and whether species from warm environments have a better ability to recapture photorespired CO2 than those from cool climates. We will also evaluate whether plants producing chloroplast sheaths have a similar potential for photorespiratory CO2 refixation as plants engineered to release photorespired CO2 within the chloroplast. The work on the early evolution of C4 photosynthesis will evaluate the functional significance of a suite of traits termed "proto-Kranz" anatomy that appear in C3 species that are closely related to C4 plants within an evolutionary lineage. Proto-Kranz anatomy may be the first definitive stage of C4 evolution and could explain how the C4 evolutionary process is initiated. We also will generate hybrids between C3 and C4 Atriplex species in order to examine the genetic controls over the expression of C4 traits. This will be accomplished by comparing transcriptomes of hybrids with differing degrees of C4 trait expression. In addition to the discovery potential of this research, funds provided will support the training of a new generation of expertise that will help the world meet the increasing demands for food, fiber and renewable energy that photosynthesis provides.

拟议的研究将提高我们对受温暖环境中高光呼吸率影响的植物的光合作用的理解。通过这项工作，我们打算通过减少光呼吸局限性，从而提高C3植物的光合作用能力来确定改善作物性能的新方法。 我们将通过（i）研究增强光急期CO2的细胞内重组的机制来评估C3植物如何补偿高光呼吸率，以及（ii）C4光合作用途径的早期演变。 在置换项目中，我们将评估叶片细胞周围周围的叶绿体鞘形成是否可以增强光递增的CO2的重新观察。我们将检查叶绿体鞘形成是否在低二氧化碳和促进光呼吸的温度下是否可以诱导，以及与凉爽气候中的温度相比，温暖环境中的物种是否具有更高的重新接收光发光二氧化碳的能力。我们还将评估产生叶绿体鞘的植物是否具有相似的光呼吸型二氧化碳来替代的潜力，因为该植物被设计为在叶绿体内释放光爆发的二氧化碳。关于C4光合作用早期演变的工作将评估称为“原始kranz”解剖结构的一组特征的功能意义，这些特征与C3物种中出现，这些解剖学与进化谱系中的C4植物密切相关。原始kranz解剖结构可能是C4进化的第一个确定阶段，可以解释如何启动C4进化过程。我们还将在C3和C4 Atriplex物种之间产生杂种，以检查对C4特征表达的遗传控制。这将通过比较具有不同程度的C4性状表达的杂种的转录组来实现。除了这项研究的发现潜力外，提供的资金还将支持培训新一代专业知识，这将有助于全世界满足光合作用提供的对食物，纤维和可再生能源的日益增长的需求。