Seasonal development
and life cycle—Crown gall
Crown gall is caused by the soil-inhabiting bacterium Agrobacterium
tumefaciens. This organism can survive in the soil for at
least 2 years in the absence of host tissue or for several years
in decomposing crown gall tissue. Bacteria are released into
the soil when galls are wet or when older gall tissue disintegrates.
Seedlings may also be affected by the bacterium during germination;
established trees and vines are infected only through fresh wounds
such as those caused by growth cracks, pruning, damage by cultivation
equipment, or freeze injury. |
Bacteria
survive in undifferentiated tissue
|
