Sclerotium rolfsii
Tags
Symptoms
Infection appears as a slight yellowing on lower leaves, water soaking and darkening of hypocotyls above the soil line, and destruction of the cortex; followed by wilting, leaf drop and death. Small (1-2 mm diam), spherical, brown sclerotia form on coarse mycelium at the plant base. The pathogen has a very wide host range.
Factors favoring
- Presence of previously infested crop debris
- Lack of crop rotation
- Poor sanitation of previous legume and weed debris
- Contaminated seed
- Susceptible varieties
- Moderate to high moisture conditions favor slugs
- Infection at V2 – R2 results in plant death, and/or reduced pod set, poor seed fill, and yield loss
Southern Blight at the base of the stem
Additional Resources
- http://legume.ipmpipe.org
- http://wiki.bugwood.org/PIPE:Legume
- http://www.apsnet.org/ - Compendium of Bean Diseases 2nd Ed.
Photo credits
H. F. Schwartz, Colorado State University, Bugwood.org