Divisi
Fusarium wilt
Fusarium oxysporum · Fungal
Photo: Victor M. Vicente Selvas · CC BY-SA 3.0
Fusarium wilt is a soil-borne fungal disease (Fusarium oxysporum) that attacks the roots of many crops — banana and plantain, tomato, common bean, cowpea, chickpea, pigeon-pea, cotton and watermelon. Each crop has its own strain of the fungus. It creeps in through the roots and grows up inside the plant's water pipes (the vascular tissue — the thin channels that carry water from root to leaf), clogging them so the plant slowly starves of water even when the soil is wet. It thrives in warm soil (25-32 C) and, once in a field, its resting spores survive there for many years.
Scot Nelson · CC0 
Clemson University - USDA Cooperative Extension Slide Series · CC BY 3.0
Why it matters
Fusarium wilt can wipe out up to 60% of your crop — on bananas or tomatoes a bad patch can mean losing more than half your plants, one wilting stand at a time. What makes it cruel is that it works from inside the plant's water pipes, so no spray can cure a plant once it is sick — by the time you see wilting, the damage is done. Worse, the fungus lives on in the soil for years and rides from field to field on infected suckers, seedlings, soil on your tools and boots, and irrigation water, so a field that gets it stays dangerous for the same crop season after season.
When to act
any plant wilting and yellowing with brown vascular streaking when the stem is cut
This guidance is general, compiled from published agronomic references including FAO and CABI. Thresholds and timing shift with your crop, your variety and the season.
In much of the region a spray is simply called mushonga — medicine. But a chemical group you cannot name is one you cannot rotate, and a product you did not write down has no pre-harvest interval you can observe. Mushonga, and other farming words →
The full fusarium wilt field guide
- Identify it
- Scout for it
- Control it
17 field-guide sections in the app
The full guide to fusarium wilt — every symptom to check, how and when to walk your field looking for it, and the controls that actually work, ranked. Built into your crop plan, so you are told to look before it costs you a harvest.
Crops it affects
Frequently asked questions
How do I identify fusarium wilt?
The first thing you notice: a plant that wilts and droops in the heat of the day, then perks up a little in the cool of the evening or morning. Day after day the wilting gets worse and the plant does not fully recover — while the plants right next to it stay healthy.
When should I take action against fusarium wilt?
any plant wilting and yellowing with brown vascular streaking when the stem is cut
How do I control fusarium wilt?
Prevent it first — plant a resistant variety (your strongest tool): where wilt is known in your area, grow a resistant variety or grafted plant matched to the local strain. This is the single most effective defence — it is your best protection because, once a plant is infected, nothing cures it.
Which crops does fusarium wilt affect?
Among the crops covered here: Banana & plantain, Chickpea, Common bean, Cotton, Cowpea, Pigeon pea, Tomato, Watermelon.
Catch it before it costs you a harvest
Divisi builds scouting into your crop plan — it tells you when to walk your field, what to look for at that stage, and what to do when you find it. Free for farmers, works offline.
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