Upon infection, dicots respond to infection by initiating massive cell division at the point of infection. Plant cells are unable to catabolize these unusual metabolites, but Agrobacterium cells can catabolize them, using them as both carbon and nitrogen sources. A. tumefaciens initiates gall formation, generally at around the soil surface near the crown. Hence the name 'crown gall' for the tumor-like structure that forms following infection. When I was 12, I was responsible for disking and tilling our olive orchard.
Olives are very shallow-rooted trees.
I drove too close to many trees. Big lumps grew from the surface roots and trunk, where I'd damaged them with the disc. These were crown galls generated by A. tumefaciens . A. rhizogenes initiates root proliferation. This pathogen was utilized in the sugarbeet transformation manuscript you previously received.