Bacterial Wilt
Erwinia tracheiphila
Found in North America, Europe, Asia, and Africa
Damage Symptoms
Crops affected are mainly cucumber and cantaloupe, but also squash and pumpkin to a limited extent. Watermelon is not affected. Foliage wilts suddenly, frequently on a single runner branch at first, followed by wilting of the entire plant. Wilt is permanent. Bacteria are abundant in the vascular tissue and exude in white droplets from vascular bundles on cut stems. The viscous bacterial mass will "string-out" when the cut ends of the stem are touched together.
Conditions for Development
The pathogen survives for extended periods in its cucumber beetle vectors. The striped beetle, Acalymma sp., and the spotted beetle, Diabrotica sp., transmit the pathogen. Therefore, conditions conducive to the development of these beetles favor the occurrence of the disease.
Control
Rogue diseased plants to prevent secondary spread of the pathogen. Control cucumber beetles with insecticides. Some cultivars are more tolerant that others, if available they should be used.
Stringing of bacterial slime from the vascular system
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