COLLABORATIVE RESEARCH: THE CRITICAL IMPORTANCE OF DIVERSE LEAF "HAIRSTYLES": INTEGRATIVE QUANTIFICATION OF ANATOMY, FUNCTION, EVOLUTION AND ECOLOGY OF TRICHOMES

人类依靠驯化的和野生的植物来获取食物、纤维、燃料和新鲜空气。因此，了解植物在当前和未来气候下的工作方式对人类福祉至关重要。植物叶毛是最复杂的、普遍存在的、重要的和鲜为人知的生物学特征之一。叶毛存在于超过一半的植物物种中，具有不同的结构和排列，影响作物和非作物物种的环境耐受性和生产力。毛状体的作用包括反射过多的光线，防止地表水的积累，减少病原体的感染，加强从饱和空气中捕获水分，减少水分流失到干燥的空气中，以及抵御食草动物。然而，对极少数物种的叶毛进行了详细的研究，因此在植物产量、进化和生态的预测中通常被忽略。这项研究将改进和开发最先进的方法来对不同物种的毛状体进行显微成像，并使用实验和模型来确定它们的成本和收益如何影响整个植物的性能。此外，该项目团队将分析葡萄藤物种、模式物种拟南芥以及加利福尼亚州和夏威夷的整个植物群的毛状体如何在不同环境和进化过程中发生变化。该项目将培训研究生和博士后科学家，掌握最先进的植物研究技术和方法，并将普通教育、高中和本科教育与公开传播研究相结合，从而提高公众对植物结构和功能的认识和兴趣。通过其合作研究团队，该项目应用了一种创新的综合方法，结合了数学、物理、生理学、生态学和进化论方面的专业知识。通过将温室和实验室实验与最先进的3D显微成像、标本馆工作、实验测量、机械和统计建模以及系统发育分析相结合，该研究将量化叶毛的解剖多样性，它们对光吸收、水分关系(润湿性和叶片水分吸收)、气体交换和防止草食的贡献，以及它们的生态和进化联系。该项目的第一个目标是将尖端的微观可视化、实验和建模相结合，以量化来自至少17个属的不同物种的叶毛的结构和多功能。第二个目标是整合这些关于叶毛多样性及其对五个已知功能的影响的多个数据流，以确定净收益如何扩大到影响整个植物的表现。第三，为了确定叶毛是如何随着谱系内和植物区系之间的气候而进化的，有必要有一个更广泛的视角。该项目将利用现有的数据和标本馆材料，专注于叶片毛状体中大规模进化和生态模式的测试案例。该项目的更广泛影响将通过加州大学洛杉矶分校植物园提供基于新结果的课程，以及包括可以在线访问和3D打印的3D模型的在线模块。所有数据都将存储在一个公开的数据库中。该奖项反映了NSF的法定使命，并已通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Humankind depends on domesticated and wild plants for food, fiber, fuel, and fresh air. Understanding how plants work under current and future climates is therefore critical to human welfare. Plant leaf hairs (trichomes) are among the most complex, ubiquitous, important, and little understood biological traits. Leaf trichomes are present in more than half of plant species, have diverse structure and arrangements, and influence the environmental tolerances and productivity of both crop and non-crop species. The effects of trichomes include reflecting excessive light, preventing accumulation of surface water, reducing infection by pathogens, enhancing water capture from saturated air, reducing water loss to dry air, and fending off herbivores. Yet, leaf trichomes have been studied in detail for very few species, and therefore have been typically ignored in predictions of plant production, evolution and ecology. This study will refine and develop state-of-the-art methods to micro-image trichomes in diverse species, and use experiments and models to determine how their costs and benefits affect whole-plant performance. Additionally, the project team will analyze how trichomes vary across environments and through evolution for species of grapevine, for the model species Arabidopsis thaliana, and for entire floras of California and Hawaii. The project will train graduate students and post-doctoral scientists in state of the art technology and approaches to plant research, and will integrate general education, high school and undergraduate education with public dissemination of research, thereby increasing public awareness and fascination with plant structure and function. Through its collaborative research team, this project applies an innovative synthetic approach combining expertise in mathematics, physics, physiology, ecology and evolution. By integrating greenhouse and lab experimentation with state of the art 3D micro-imaging, herbarium work, experimental measurements, mechanistic and statistical modeling and phylogenetic analyses the research will quantify the anatomical diversity of leaf trichomes, their contributions to light absorption, water relations (wettability and foliar water uptake), gas exchange, and protection from herbivory, and their ecological and evolutionary associations. The first aim of this project is to combine cutting edge micro-visualization, experimentation and modeling to quantify the structure and multiple functions of leaf hairs in diverse species from at least 17 genera of flowering plants. The second aim is to integrate these multiple streams of data on the diversity of leaf trichomes and its influence on five known functions to determine how the net benefits scale up to influence whole plant performance. Third, an even wider perspective is necessary to determine how leaf trichomes evolved with climate within lineages and across floras. The project will leverage available data and herbarium material to focus on test cases of large-scale evolutionary and ecological patterns in leaf trichomes. The project’s Broader Impacts will provide curricula based on novel results via the UCLA Botanical Garden, and online modules including 3D models that can be accessed online and 3D printed. All data will be deposited in a publicly available database.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.