gummy stem blight of watermelon
Figure 1. Gummy stem blight causes dark, amorphous, necrotic lesions on watermelon leaves. 
Figure 2. Gummy stem blight lesions on watermelon leaves sometimes have a ring-like structure. 
Figure 3. Underside of a watermelon leaf with a gummy stem blight lesion. 
Figure 4. Large gummy stem blight lesion along the midrib of a watermelon leaf 
Figure 5. Close up of gummy stem blight lesions on a watermelon leaf, one lesion with a shot-hole. 
Figure 6. Lesion of gummy stem blight on a watermelon leaf petiole. 
Figure 7. Lesion of gummy stem blight on a watermelon stem. The brown ooze or gum does not always occur in association with this disease and many other diseases and injuries to the stem may cause such an ooze. 
Figure 8. Fruiting bodies, pycnidia, on a watermelon leaf petiole. 
Figure 9. A field of watermelon with a severe outbreak of gummy stem blight manifested by defoliation and numerous lesions.