charcoal rot of cucumber
Figure 1. Charcoal rot of cucumber. Plant wilt is often the first symptom observed. 
Figure 2. Charcoal rot of cucumber. Plant wilt is visible and lesion on lower stem. 
Figure 3. Charcoal rot of cucumber. Light gray lesion on stem with micro-sclerotia shown. 
Figure 4. Charcoal rot of cucumber.