When [microbiologist Pilar] Junier and [mycologist Daniel] Job cultured M. crassipes and P. putida together, they saw that the fungi formed sclerotia at the point on the plate farthest from the spot where the bacteria had been inoculated.
Over a series of experiments, the researchers observed the fungus dispersing the bacteria, then feeding them with fungal exudates, and finally harvesting carbon from the bacteria and storing it in sclerotia.
Besides the distribution, feeding, and harvesting of the bacteria by the fungus, two other observations convinced Junier that what they saw was truly farming. The ability of sclerotia to store bacteria and then later redistribute them on a fresh plate is similar to seed storage in human agriculture.
Junier explains that they also observed M. crassipes harvesting carbon from the bacteria in one area and storing it in another, which mirrors the way that humans use farm animals.