On squash and pumpkin fruit, this disease is called black rot. Symptoms When emerging seedlings are infected, circular tan to black spots appear on cotyledons and stems. If the stems become girdled, damping-off results and seedlings die. When stem infections occur on older plants, water-soaked lesions result. These lesions become dry, cracked and tan.
Large lesions girdle the vine, resulting in wilt.
A gummy reddish-brown exudate is usually associated with the cankers. Foliar infections cause formation of necrotic spots on the leaves or leaf edges. These necrotic areas may progress over the entire leaf, but they primarily occur along the veins. Black rot symptoms can develop on pumpkin and squash fruit in the field or storage. Initially, small water-soaked spots develop on the infected fruit surface.