symptoms
Symptoms
- circleV-shaped yellow lesions starting at leaf edges (in brassicas) or circular dark spots
- circleBlackened veins visible in cut stems
- circleFruit or root tissue turning black and shriveled
help
Causes
Caused by fungi such as Guignardia (grapes) or the bacterium Xanthomonas campestris (brassicas), spreading through water splash and contaminated seed in warm, wet weather.
healing
Treatment
Remove and destroy infected plant parts, avoid overhead watering, and apply an appropriate fungicide or bactericide labeled for the specific host plant.
shield
Prevention
Use certified disease-free seed or stock, practice crop rotation, and clean up plant debris at the end of the season.