EAGER: Interrogating Plant Volatile Reports About the Environment

植物能迅速发现并对变化的环境作出反应。这使它们成为环境事件的敏感指标。气味，或“挥发性有机化合物”（VOC）是由植物主动释放的，以应对包括干旱，疾病和昆虫攻击在内的压力。挥发性有机化合物的混合物提供了植物所经历的“指纹”。挥发性有机化合物可以吸引害虫的有益敌人攻击植物。例如，寄生蜂被吸引到植物被黄蜂正在寻找的昆虫吃掉。挥发性有机化合物也被认为是“提示”邻近植物即将发生的危险。健康的植物暴露在来自受损或患病植物的气味中，会启动防御反应，这可能有助于它们生存。挥发性有机化合物的浓度非常低，因此迄今为止所有关于其生态作用的实验都是在室内进行的。还没有人在户外或自然环境中采样挥发性有机化合物。该项目将生产一种新的挥发性有机化合物采样和分析仪器，能够表征植物在露天的反应“指纹”。该项目将采用一种基于激光光子学和微流体的新型化学传感器，称为光流体环形谐振器（OFRR）。OFRR只需要20纳升的样品体积，因此可以检测和识别极低浓度的VOC。在一系列的实验中，首先使用购买的气味，然后使用真实的植物，OFRR将被改进，以分析浓度远低于当前最先进水平的植物VOC。该设备将首次用于证明，一种植物排放的VOC确实会传播到另一种植物，并在户外引起另一种植物的反应。除了证实一个长期存在的重要科学假设外，该项目还提供了许多有价值的技术应用。这些能力包括感知有害生物对植物个体的损害，以进行经济的现场处理，利用植物作为环境质量的监测器，了解复杂的植物-昆虫相互作用，以及收获后的食品质量和安全评估。该项目将培养本科生和研究生在一个独特的工程/生物学互动，并将作为邦德生命科学中心的广泛的科学教育和推广计划的重要组成部分。

Plants rapidly detect and respond to changing conditions. This makes them sensitive indicators of environmental events. Odors, or "volatile organic compounds" (VOCs) are actively emitted by plants in response to stresses, including drought, disease, and insect attack. The mix of VOCs provides a "fingerprint" of what the plant has experienced. VOCs can attract beneficial enemies of pests attacking a plant. For example, parasitic wasps are drawn to plants being eaten by the insect the wasps are seeking. VOCs are also thought to "cue" neighboring plants about imminent danger. Healthy plants exposed to odors from damaged or diseased plants initiate defense responses that may help them survive. VOC concentrations are very low, so all experiments on their ecological roles have so far been done indoors. No one has yet sampled VOCs functioning in open air, or in natural settings. This project will produce a new VOC-sampling and analysis instrument capable of characterizing plant response "fingerprints" in open air. This project will employ a novel chemical sensor based on laser photonics and microfluidics, called an opto-fluidic ring resonator (OFRR). The OFRR requires a sample volume of only 20 nano-liters and so can detect and identify VOCs at extremely low concentrations. In a series of experiments done with purchased odors and then with real plants, the OFRR will be refined to analyze plant VOCs at concentrations well below the current state of the art. The device will be used to demonstrate for the first time that VOCs emitted by one plant really do travel to and turn on responses in another plant in open air. Besides confirming a long-held and important scientific hypothesis, this project offers numerous valuable technical applications. These include the ability to sense pests damaging individual plants for economical spot-treatment, using plants as monitors of environmental quality, understanding complex plant-insect interactions, and post-harvest food quality and safety assessment. The project will train undergraduate and graduate students in a unique engineering/biology interaction, and will serve as an important component of the Bond Life Science Center's extensive science education and outreach program.