B093-0001
Exploring the role of volatile organic compounds in the rhizosphere interactome
Tuesday, 15 December 2020
Poster
Laura K Meredith1, Jordan E. Krechmer2, Juliana Gil-Loaiza1, Joseph R Roscioli3, Joanne H Shorter2, Megan Claflin2, Lars Erik Daber4, Jane Fudyma5, Johannes Ingrisch6, Kathiravan Meeran6, Giovanni Pugliese7, Thomas Kluepfel7, Eva Y Pfannerstill8, Jonathan Williams8, Linnea K Honeker9, Malak M Tfaily9, S. Nemiah Ladd10, Christiane Werner4 and Water, Atmosphere and Life Dynamics (WALD), (1)University of Arizona, School of Natural Resources and the Environment, Tucson, AZ, United States, (2)Aerodyne Research Inc., Billerica, MA, United States, (3)Aerodyne Research Inc, Billerica, MA, United States, (4)University of Freiburg, Freiburg, Germany, (5)University of Arizona, Environmental Science, Tucson, United States, (6)University of Innsbruck, Institute of Ecology, Innsbruck, Austria, (7)Max Planck Institute for Chemistry, Mainz, Germany, (8)Max Planck Institute for Chemistry, Atmospheric Chemistry Department, Mainz, Germany, (9)University of Arizona, Tucson, AZ, United States, (10)ETH Swiss Federal Institute of Technology Zurich, Earth Science, Zurich, Switzerland
Abstract:
Roots and microbes interact through gas-phase metabolites and signaling molecules including volatile organic compounds (VOCs). VOCs show potential as biomarkers for specific processes and interactions belowground, individually, or as the volatile subset of the comprehensive metabolome of an organism or ecosystem—coined the volatilome. Recently, we developed a non-invasive, online soil gas sampling approach to measure subsurface VOCs in real time. Here, we present an intercomparison of VOC measurements from three soil perspectives—subsurface, surface, and isolated roots—to explore the role of VOCs in the belowground during a controlled, whole ecosystem drought.
As part of the Water, Atmosphere, and Life Dynamics (WALD) drought campaign in the Biosphere 2 Tropical Rainforest, we measured subsurface VOC concentrations during mid-drought from the following locations: 1) triplicate probes buried across a 15-30 cm depth range in a rhizosphere dense location within 0.5 m of a sugar palm (Arenga pinnata) and a control location 2.0 m away; and 2) probes installed in a soil pit at 20, 50, 150, 200, and 300 cm depths. Soil probes were sampled over four days with a Vocus proton transfer reaction time of flight mass spectrometer (PTR-TOF-MS) resulting in a time series data for a set of 64 identified VOC masses.
In this presentation, we will compare the subsurface soil VOC data set to 1) root VOC emission profiles measured by the Vocus and 2) soil-atmosphere fluxes measured during pre-drought and drought periods by a separate PTR-TOF-MS auto-chamber system. With these data, we look through a new window into the biochemical nature and spatiotemporal dynamics of subsurface soil interactions mediated by VOCs.
