Root rot of sweetpotato generally appears as circular lesions with light and dark brown concentric rings (Figure 1). Unlike surface rot of sweetpotato, root rot extends past the periderm and into the central parenchyma of the root often forming open cavities in the tissue (Figure 2). Infected tissue turns dark brown with the advancing margins appearing light brown. Root rot may also be initiated at the proximal or distal end of the sweetpotato, giving the name of the disease “end rot.” Enlarged lesions become dry and sunken and white mycelia may be visible on the outside of the lesion or in the inner cavities.
Figure 1. Circular lesion with concentric rings typical of Fusarium root rot.
Andrew Scruggs and Dr. Lina Quesada, NC State Vegetable Pathology Lab
Figure 1. Circular lesion with concentric rings typical of Fusarium root rot.
Figure 2. Cross-section of Fusarium root rot, displaying typical symptoms of dry, open cavities. White mycelia of F. solani can be seen growing inside the cavities.
Andrew Scruggs and Dr. Lina Quesada, NC State Vegetable Pathology Lab
