Fusarium Wilt
Symptoms:
- When disease begins, wilting may occur but plants often recover their
stature overnight.
- Stems and leaves of only one side of a plant may initially discolor
or wilt.
- The leaves and stems develop chlorois and turn light in color.
- As the disease progresses the entire plant may wilt, develop a yellow
or reddish tint, and die after several months.
- Dark brown specks develop near the center of the root and often increase
to form a complete or partial circle; this diagnostic symptom is best
seen by cutting cross-sections of upper part of the root.
- Infected plants usually occur in scattered patches in a field
Pathogen Involved:
- Fusarium oxysporum f. sp. medicaginis (a fungus)
- The fungus infects through wounds in roots.
- Survives in soil and infested plant debris
Time of Occurrence:
- All season
- Most common in stands two or more years old
Conditions Favoring Disease:
- Warm soil temperatures favor this disease, and is not favored by
high soil moisture.
- Root knot nematode injury can increase severity of Fusarium wilt.
Disease Management:
- Use cultivars with resistance to Fusarium wilt and to the root knot
nematode
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