CAREER: Next-generation Rhizosphere Monitoring - Non-invasive Plant Phenotyping and Health Monitoring Using the Light-piping Properties of Plant Stems

Harvey Mudd学院（HMC）开发了一种新的光学技术，通过利用植物茎和根的光管特性来监测根系的功能和结构，从而获得了一个奖项。该项目将开发一种新的仪器来测量诸如根长和生长动态等数量。该教育计划将本科生和高中生纳入研究活动，他们将在工程，光学和植物生物学的界面上学习广泛的技能。该项目将通过参加国际会议和个人指导来支持学生的职业发展。一个3d打印，低成本的计算显微镜平台将围绕树莓派和连接的相机开发，作为一种教学工具，通过显微镜教授光学概念。该项目还将支持开发与硬件平台配套的动手实验课程，并指导学生探索光-物质相互作用和计算显微镜技术。HMC将为本科生和本地高中生提供年度研讨会，以吸引学生进入STEM领域，并提供工程方面的体验式学习机会。该项目的科研目标是利用植物茎和根的光管特性，开发下一代光学工具来研究植物根及其周围环境。根系及其局部地下环境对植物的健康和生长起着至关重要的作用。除了在物理上锚定和稳定植物外，根系还提供了从土壤中获取资源的途径，并在植物与地下环境之间建立了化学和生物联系。这意味着关于根系的信息对于实验室和田间的植物生物学和农业研究至关重要，为监测和改善植物生长、生产力和可持续性提供了定量指标。不幸的是，土壤在光学波长下不是透明的，阻碍了对根系的直接成像。目前克服这一挑战的策略包括使用透明生长介质，称为根状管的玻璃壁成像系统，或替代成像方法，如x射线计算机断层扫描，磁共振成像或正电子发射断层扫描。然而，这些解决方案都很昂贵，而且只能探测整个根系的一小部分。该项目的目标是开发一种微创仪器，将光注入茎和根系，捕获和分析背向散射光，以绘制根系结构。该项目将探索实现这一目标的两种主要仪器结构：飞行时间探测和低相干干涉测量。在开发过程中，这些仪器还将用于探索植物茎和根的光学特性。除了在同行评议的期刊上发表该项目的结果和在科学会议上发表报告外，还将向公众提供有关如何建造和操作这些仪器的说明。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

An award is made to Harvey Mudd College (HMC) for the development of a new optical technology to monitor the function and structure of root systems by exploiting the light-piping properties of plant stems and roots. The project will develop a new instrument to measure quantities such as root length and growth dynamics. The education plan integrates undergraduate and high school students into the research activities where they will learn a broad set of skills at the interface of engineering, optics, and plant biology. The project will support student career development through international conference participation and individual mentorship. A 3d-printed, low-cost computational microscopy platform built around a Raspberry Pi and a connected camera will be developed as a pedagogical tool to teach optics concepts through microscopy. The project will also support the development of a curriculum of hands-on experiments to accompany the hardware platform and guide students as they explore light-matter interactions and computational microscopy techniques. Annual workshops will be offered at HMC for undergraduate and local high school students to attract students to STEM fields and offer experiential learning opportunities in engineering.The scientific research goal of the project is to exploit the light-piping property of plant stems and roots to develop the next generation of optical tools to investigate plant roots and their surrounding environments. Roots and their local underground environment play a critical role in plant health and growth. In addition to physically anchoring and stabilizing the plant, the roots provide a pathway to acquire resources from the soil and establish a chemical and biological link between the plant and the below-ground environment. This means that information about the root system is critical for plant biology and agricultural studies both in the laboratory and the field, providing quantitative metrics for monitoring and improving plant growth, productivity, and sustainability. Unfortunately, soil is not transparent at optical wavelengths and stymies direct imaging of the root systems. Current strategies to overcome this challenge include using a transparent growth medium, glass-walled imaging systems called rhizotrons, or alternative imaging methodologies such as X-ray computed tomography, magnetic resonance imaging, or positron emission tomography. However, these solutions are expensive and offer the ability to probe only a small fraction of the overall root system. The goal of this project is to develop a minimally-invasive instrument that will inject light into the stem and root system, capturing and analyzing the backscattered light to map out the root structure. The project will explore two main instrument architectures for achieving this goal: time-of-flight detection and low-coherence interferometry. In the development process, the instruments will also be used to explore the optical properties of plant stems and roots. In addition to the publication of results from this project in peer-reviewed journals and presentations at scientific conferences, instructions on how to build and operate the instruments will be made publicly available.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.