Title : Plant-environment microscopy tracks interactions of Bacillus subtilis with plant 1 roots across the entire rhizosphere

Affiliations: 6 1 School of Science and Engineering, University of Dundee, Dundee, UK 7 2 Ecological Sciences, The James Hutton Institute, Dundee, UK 8 3 Department of Conservation of Natural Resources, Neiker, Bilbao, Spain 9 4 School of Life Sciences, University of Dundee, Dundee DD1 5EH, United Kingdom 10 5 Ingénierie et Architectures Macromoléculaires, Institut Charles Gerhardt, CNRS, 11 University of Montpellier, ENSCM, Montpellier, France 12 6 Department of Animal and Plant Sciences, The University of Sheffield, Sheffield, UK 13 7 Northern Faculty, Scotland’s Rural College, Aberdeen, United Kingdom 14 8 IKERBASQUE, Basque Foundation for Science, Bilbao, Spain 15