Fusarium Wilt (Stem Rot) - Photograph of lesions on sweet potato stems caused by Fusarium oxysporum sp. batatas. Streptomyces soil rot of sweetpotato - Symptoms of this widespread and destructive disease, its cause and development, and its management. Sweetpotato Scurf - Information on this disease caused by the fungus Monilochaetes infuscans, and how to manage it. Nematode Management in Sweet Potatoes - Information on general IPM considerations, symptoms, damage, field diagnosis and sampling, general management considerations and chemical control. Sweetpotato Weevil: Cylas formicarius - Information, management and references for this serious worldwide pest. Diseases of Sweetpotato - Provides the common names of the bacterial, fungal, nematode, viral and other diseases that affect the plant.