Agrobacterium tumefaciens

Agrobacterium tumefaciens is a flagellated bacterium, which is why it can spread on its own through the irrigation system. It is responsible for various diseases in crops.

In tomatoes—as well as in cucumbers, eggplants, and zucchini—it is responsible for what are known as “crazy roots.” In roses, for example, it causes crown gall, which are tumor-like growths that appear primarily on the roots, but also at the base of the stem or at grafting sites. As with crazy roots, water transport is disrupted; the weakened plants grow more slowly, and a large amount of low-quality produce is produced.