The rhizosphere is a dynamic ecosystem that is difficult to study due to the volume and types of interactions that occur. Trent Northen is an author on the review paper “Specialized Plant Growth Chamber Designs to Study Complex Rhizosphere Interactions” that takes a look at different types of chambers and their strengths and drawbacks.
Some of the technologies discussed include rhizotrons or rhizoboxes (containers with one to two transparent sides), compartmental setups for fungi (which restrict roots but not mycorrhizal fungi), and microfluidic devices (where control over small channels allows for better reproducibility).
To learn more about different plant chambers and other ways in which the rhizosphere can be investigated, read the full paper.