| Root dieback: Pythium debaryanum, P. aphanidermatum |
Symptom:
- Pythium brown rot and forking
- Root dieback of carrots produces excessively branched or stubbed roots
- Fungus kills young tap roots after seed germination, reducing root length and/or stimulating forking
- Forking and stubbing occur, but these symptoms can also be caused by soil compaction, nematodes
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| Forking |
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Stubbed roots |
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| Identification of pathogen:
Mode of spread and survival:
- Produce sporangia and oospores
- Spores and mycelia are responsible for the spread of the fungus in the field, which is facilitated by wet soil conditions
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Management:
- Avoiding excessive watering
- By providing good field drainage
- Planting carrots in deep, friable and well drained soils
- Post emergence fungicides - Mefenoxam - to control damping-off
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Source of Images:
http://www.extension.umn.edu/garden/diagnose/plant/vegetable/carrot/rootforked.html |
