Plants get cancer too

It sound odd, but plants do in fact get a form of cancer. Because they don’t have a closed circulation like us mammals do, and because their cell walls make the cells unable to move about, they don’t get metastases, but they can get remarkable large local tumors. Again, because the cells are not motile, the tumors don’t invade, and the can be removed without (usually) killing the plant.Here is an example—a crown gall tumor on a forsythia shrub:

The cause of this tumor is an infection with the bacterium Agrobacterium tumefaciens. This interesting organism infects and passes a piece of DNA called a plasmid into the nearby plant cells. The DNA codes for genes that activate the cell’s production of plant growth hormones such as auxin, and the cells undergo rapid and, for them, uncontrollable growth. Crown Gallisaserious plant disease for some crops.

Galle du collet sur Forsythia due à Agrobacterium tumefaciens. Image by Christophe Quintinvia Flickr. CC BY-NC 2.0