[paul.fr]

Humans and other animals get cancer, but is it possible for plants to get cancer?

[Karen W.]

OHHH That is a good question!...

[chris]

Yes they do, and just as some cancers in humans are triggered by bacterial and viral infections, so too are certain plant tumours.

For instance, the bacterium Agrobacterium tumefaciens, which is used by GM-plant engineers to shuttle new genes into crops, causes "crown gall disease" by inserting growth-promoting genes into some plant cells.

Chris

[tony6789]

hmm interesting...yea a fantastic question...idk now that chirs but i wud definetly think they do just diffrent kinds than us

[Queequeg]

So, if we analogize human cancers to different growth and development derangements in plants, there are a couple that tend to make for pretty cool looking patterns in the vegetation.  Witches brooms, for example, are indeed actually kind of spooky looking (at least to my eye) when seen in the tree branches in winter ( newbielink:http://www.ipm.iastate.edu/ipm/hortnews/2005/2-23-2005/witchesbroom.html [nonactive])

Witches brooms can be caused by viruses, fungi, bacteria-like organisms, and mutations. 

Galls (on branches and flowering parts rather than crown gall) are often caused by insects and one gall condition that is particularly common where I live is galls on oak tree branches.  ( newbielink:http://www.ento.psu.edu/extension/factsheets/gallsOnOak.htm [nonactive]).  These galls are caused by the larvae of small wasps in the family Cynipidae. Affected trees get completely taken over with galls on all of the small, twig-sized branches and they look completely freaky.

Eric