ring rot

noun

1

: decay in a log following closely the annual rings

2

a

: 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

c

: brown rot sense 1c

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