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: 2013
• 资助国家: 加拿大
• 起止时间: 2013-01-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=522534
• 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.

这项拟议中的研究将提高我们对植物光合作用的理解，这种光合作用受到温暖环境中发生的高速率光呼吸的影响。通过这项工作，我们打算确定新的方法来提高作物性能，减少光呼吸限制，从而提高光合能力的C3植物。 我们将评估C3植物如何补偿高速率的光呼吸（i）研究机制，提高细胞内再固定的光呼吸CO2，和（ii）的C4光合途径的早期演变。 在再固定项目中，我们将评估围绕叶细胞周围的叶绿体鞘的形成是否增强了光呼吸CO2的再同化。我们将研究，如果叶绿体鞘的形成是诱导下低CO2和温暖的温度促进光呼吸，以及是否有更好的能力，从温暖的环境中的物种比那些从凉爽的气候夺回photorespired CO2。我们还将评估植物产生叶绿体鞘是否具有类似的潜力，为植物的光呼吸CO2再固定的叶绿体内释放光呼吸CO2。C4光合作用的早期进化的工作将评估一套被称为“原Kranz”解剖学的特征的功能意义，这些特征出现在与C4植物在进化谱系中密切相关的C3物种中。原始Kranz解剖可能是C4进化的第一个决定性阶段，并可以解释C4进化过程是如何开始的。我们还将产生C3和C4滨藜物种之间的杂种，以检查C4性状表达的遗传控制。这将通过比较具有不同程度的C4性状表达的杂交种的转录组来实现。除了这项研究的发现潜力外，所提供的资金还将支持新一代专业知识的培训，这将有助于世界满足对光合作用所提供的食物，纤维和可再生能源日益增长的需求。