ring rot
nounDefinition of ring rot
1
: decay in a log following closely the annual rings
2a
: a disease of sweet potatoes caused by a fungus (Rhizopus stolonifer) in which the roots are girdled by bands of dry rot
b
: a disease of potatoes caused by a bacterium (Clavibacter michiganensis sepedonicus synonym Corynebacterium michiganensis sepedonicus) and characterized by browning of the ring of vascular bundles
— called also ring disease