Seed piece decay—Fusarium spp. and Erwinia
The first signs of seed piece decay are reddish brown to black spots that slowly form depressions on
the surfaces of cut seed pieces. Later these spots may become black and slimy from bacterial infections.
Entire seed pieces will rot and fail to emerge if enough infections develop. Seed piece decay reduces
stands, results in variable plant size, and may increase the incidence of blackleg.
Plant only certified
seed potatoes. Cut them when sprouts just begin to form and plant the seed pieces
immediately. Plant when soil temperature is above 45° F.
For more information, see the Damping -off Diseases in the Garden Pest Note.
brown spots of seed piece decay