Abstract
Background
The simple term “rhizosphere” is well defined and has inspired numerous studies from a broad field of science since the beginning of the 20th century. However, we still know very little about the spatial and temporal heterogeneity of rhizosphere processes. This is mostly because assessing rhizosphere heterogeneity is not a trivial task. One technology for high-resolution and quantitative imaging of rhizosphere processes is called planar optode technology. This technology can create quantitative maps of key rhizosphere parameters non-invasively and has great potential to reveal new insights into this biogeochemical hotspot.
Scope
Rudolph and coworkers in this issue of Plant and Soil have used and improved the application of the planar optode technology for mapping rhizosphere pH dynamics. My commentary discusses the advantages and disadvantages of their approach and those of other published studies that deal with other planar optodes (like O2, CO2 or ammonium concentration) compared to conventional techniques.
Conclusions
Planar optodes represent a unique and powerful technology that can be used to investigate a range of rhizosphere processes. For sure there are more steps to take in order to tap the full potential of this technology: we now need concerted interdisciplinary approaches between biology, sensor chemistry and digital image analysis to scope out its full potential.
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I thank Vicky Temperton for very fruitful discussions and language editing.
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Blossfeld, S. Light for the dark side of plant life: —Planar optodes visualizing rhizosphere processes. Plant Soil 369, 29–32 (2013). https://doi.org/10.1007/s11104-013-1767-0
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DOI: https://doi.org/10.1007/s11104-013-1767-0