Plant Problem Diagnosis Key / Diseases
Disease
Bacterial wilt of cucurbits
Erwinia tracheiphila
Bacteria spread by cucumber beetles that clog the vine's water tissue. Cucumber and muskmelon are most susceptible; squash and pumpkin less so; watermelon is resistant.
Signs
- A single leaf or runner wilts, then the whole vine; it may recover overnight at first, then wilts each day until it dies.
- Cut stem ends pressed together and pulled slowly apart draw out thin sticky strands.
- Cucumber beetles feeding on the plants.
What favors it
Cucumber beetles feeding early in the season.
Prevention
- Protect young plants before cucumber beetles appear (see Cucumber beetles).
- Row cover until bloom.
Crops it shows up on
Cucumber, squash & melon; Tomato, pepper & eggplant.
Often confused with
Sources
- Bacterial wilt of cucurbitsUniversity of Minnesota Extension
- Striped Cucumber Beetles and Bacterial WiltUniversity of Maryland Extension
Treatment by crop
Cultural, biological and chemical options in the order to use them, and notes written for each crop.
Identification is free. Treatment is on the Home and Pro plans.
Questions in the key that lead here
- Look the plant over, leaf undersides included. Are insects, mites, slugs, eggs, webbing or droppings on it?
No, only damage or discoloration - Where is the problem?
The whole plant or whole stems - How is the soil or media?
Moist or wet - Lift the plant or pull back the media at the stem. What do the roots look like?
White or cream, firm - Which plant is wilting?
Cucumber, melon or squash - Check the stem.
No hole. Cut the wilted stem, press the ends together and pull apart slowly
Not a match? Start the key or describe what you see.
More photos
More from university Extension: search Extension pages on bacterial wilt of cucurbits, or find a plant diagnostic lab through your state's Extension.
Other diseases
- Anthracnose
- Apple scab
- Bacterial leaf scorch
- Bacterial leaf spot
- Bacterial wetwood (slime flux)
- Black knot
- Black spot of rose
- Bleeding canker
- Boxwood blight
- Canker diseases
- Cedar-apple and related rusts
- Crown gall
- Damping-off
- Downy mildew
- Dutch elm disease
- Early blight and Alternaria leaf spot
- Elm yellows (phloem necrosis)
- Fire blight
- Fusarium wilt
- Gray mold (Botrytis)
- Late blight
- Mosaic viruses
- Needle cast and tip blight
- Oak wilt
- Powdery mildew
- Root and butt rot
- Root rot (Pythium and Phytophthora)
- Rust
- Septoria leaf spot
- Shade tree anthracnose
- Sooty mold
- Tar spot of maple
- Tomato spotted wilt and impatiens necrotic spot viruses
- Verticillium wilt
- White mold (Sclerotinia)
- White pine blister rust