Composite 12C15N-/12C14N- HSI ion image of a cross section of a Setaria veratis root grown in hydroponic co-culture with Azospirillum brasilense. The medium was supplemented with 13C- and 15N-labeled indole-3-acetamide in order to probe the interkingdom trafficking of auxin-related compounds and the effects of bacteria-plant interactions on plant growth. Nearly all plant tissues show signs of 15N enrichment while the bacterial biofilms external to the root are enriched to greater than 15 atom% 15N (40,000 ‰).
Recorded on CAMECA NanoSIMS 50L at the Environmental Molecular Sciences Laboratory at PNNL, USA. Image courtesy of J. Cliff.
Principal investigator R. Ferrieri, University of Missouri, and sample preparation and analysis A. Ferrieri, A. Dohnalkova, and J. Cliff, PNNL.