An in-situ device to monitor root-soil-microbe interactions

Finding better ways to measure rhizosphere properties has the potential to transform agriculture. Better understanding of the root-microbe-soil interactions that characterize the rhizosphere will help reduce fertilizer, pesticide, and herbicide inputs, improve effective carbon dioxide sequestration, enhance biofuel crop production, and lead to more efficient farms with higher profitability. But the rhizosphere is difficult to measure, requiring soil samples, complex spectroscopy, and other expensive and time-consuming procedures, which limit the pace of innovation.The device to be developed under this proposal overcomes these challenges, combining cutting edge root detection technology with an ingenious suite of inexpensive, single-band LED emitters/detectors to replace mid-infrared spectroscopy. Unlike other approaches, like soil sampling, the device functions in the field and can monitor the rhizosphere continuously without human intervention. Phase I work aims to provide proof-of-concept evidence that the suite of single-band LED emitters/detectors can replace mid-infrared spectroscopy and that LED emitters/detectors can identify roots. These two endeavors will demonstrate that the proposed device can measure important soil properties near roots, in effect, measuring key rhizosphere properties