What's the difference between Fusarium and Verticillium wilt?
Written by
Kiana Okafor
Reviewed by
Prof. Martin Thorne, Ph.D.Treatment for verticillium wilt can be indistinguishable from Fusarium in terms of vascular symptoms, but the biology and physiology of the fungus are different. Fusarium prefers warm soils (75-85°F), while verticillium causes the most damage at 60-75°F. I have personally confirmed cases in the field where a misdiagnosis resulted in ineffective treatment of verticillium wilt rather than Fusarium for the reasons associated with the identification. Identification is key to determining the success of your treatment.
Temperature & Host Range
- Verticillium: 300+ hosts including maples and tomatoes
- Fusarium: Host-specific (e.g., Fusarium oxysporum f.sp. lycopersici targets tomatoes)
- Verticillium microsclerotia survive 15+ years vs Fusarium's 5-7 year chlamydospores
Management Strategies
- Solarize Verticillium at 120°F for 6+ weeks
- Fusarium requires 130°F soil temps for control
- Crop rotation: 3+ years non-hosts for both
The diagnostic hint is that *Fusarium* shows *brown vascular streaks, with white sporulation* while streaks show darker without spores for the *Verticillium* pathogen. A client's tomato patch had both *Fusarium* and *Verticillium* pathogens so we used soil thermometers and lab tests to set soil solarization temperatures accordingly. For mixed infections, we have to consider using phased treatments.
Avoid cross-contamination with good tool management. Fusarium is spread through infected seed and Verticillium through soil. It is best to use separate tools for tomatoes, which are prone to Fusarium, and for maples that are susceptible to Verticillium. Designate tools by coloring the handles for the each group: red for nightshades, blue for woody plants. Bleach solutions are effective in killing both pathogens when mixed as needed.
It's important to select resistant cultivars wisely. For instance, 'Fusarium Shield' for tomatoes is not resistant to Verticillium, whereas 'Verticil-Proof' for maple is not resistant to Fusarium. A customer with a berry farm has used both ' Sweet Charlie' (resistant to Verticillium) and 'Camarosa' (resistant to Fusarium) strawberries each producing alternate years to effectively reduce soil pathogen populations (70%) over three consecutive seasons.
Read the full article: Verticillium Wilt Treatment: Complete Management Guide
