On 3 September 2025, inspectors registered a suspected case of Fusarium wilt Tropical Race 4 on a seven-hectare banana farm in Santa Rosa, in the province of El Oro. On 18 December 2025, Agrocalidad and the Ministry of Agriculture confirmed it and declared a six-month phytosanitary emergency. In July 2026 a second case was confirmed on a neighbouring property.
Ecuador became the fourth country in the region to confirm TR4, after Colombia in 2019, Peru in 2021 and Venezuela in 2023. For the world’s largest banana exporter, the arrival of the disease is the most serious threat the industry has faced in two generations. Researchers at ESPOL have warned of potential losses of up to 8.3 billion dollars over 30 years.
Agrocalidad has stressed that the disease poses no risk to human health, that the fruit does not carry it, and that exports have not been affected. The focus is containment.
In the months since, growers have been searching for anything that might help. Much of what they will be offered, including by fertilizer sellers, will overstate what it can do. This guide sets out what the evidence actually supports.
If you see suspicious symptoms on your farm, report them to Agrocalidad on 1800 247 600 before doing anything else.
First, why this disease is different
TR4 is a soil-borne fungus that enters banana through the roots and blocks the plant’s vascular system, causing wilting and death. It produces thick-walled spores that can survive in soil for decades without a host.
Ecuador has lived through this before. In the 1960s, Fusarium Race 1 devastated the Gros Michel variety that then dominated Ecuadorian exports, and the industry survived by moving to Cavendish. TR4 attacks Cavendish. There is, for now, no commercial Cavendish replacement that resists it at scale.
Once a field is infested, it cannot be cleaned. That single fact shapes everything else in this guide.
What nutrition cannot do
Be clear about this, because the pressure to believe otherwise will be strong.
No fertilizer prevents TR4. A well-fed banana plant can still be infected.
No fertilizer cures TR4. An infected plant cannot be nursed back to health with nutrients.
No nutrient programme makes an infested field safe. Researchers who tested mineral fertilization on soils of different pH found reduced plant mortality and disease expression with better soil chemistry, but they concluded that soil chemical management alone would not prevent the disease from building up.
No product replaces biosecurity. The disease spreads in infested soil and plant material, on boots, tools, vehicles, water and planting material. Stopping that movement is the only thing that protects a clean farm.
Anyone selling a fertilizer, biostimulant or soil amendment as a solution to TR4 is selling something the evidence does not support.
What nutrition can do
Within those limits, soil condition and plant nutrition do appear to influence how severely Fusarium wilt develops, and they matter for plantation health generally.
A review of soil properties and Fusarium wilt across many crops found disease severity was generally lower where soil pH, organic matter, and the availability of calcium, zinc, silicon, potassium, phosphorus and boron were higher, and where nitrate made up a larger share of the nitrogen. Severity tended to be higher with more available iron and manganese. The authors noted that the agreement was weaker for banana than for some other crops, which is a reason for caution rather than dismissal.
A 2025 study of 47 banana farms on Hainan Island in China, where the soils were strongly acidic, found disease incidence was strongly and negatively linked to soil pH, exchangeable calcium and magnesium, and available potassium.
Taken together, the evidence supports a sensible, modest set of practices:
| Practice | What the evidence suggests | How firm it is |
|---|---|---|
| Correct strongly acidic soil | Higher pH is associated with lower disease severity | Reasonably consistent |
| Maintain calcium, magnesium and potassium | Deficiencies linked to higher disease incidence | Reasonably consistent |
| Favour nitrate over ammonium nitrogen | Ammonium associated with greater Fusarium wilt severity | Supported across crops |
| Build soil organic matter and biology | Organic amendments and beneficial microbes can suppress disease in trials | Promising, variable in the field |
| Avoid unnecessary iron and manganese | Higher levels associated with greater severity | Supported across crops, less so for banana |
| Keep zinc and boron adequate | Associated with lower severity | Moderate |
Every row is a supporting practice for plantation health. None is a control.
Putting it into a programme
Test before you apply. A soil analysis showing pH, exchangeable calcium, magnesium and potassium, organic matter, and iron and manganese tells you which of the practices above actually applies to your farm.
Correct acidity where it exists. Lime or other soil correction comes first on strongly acidic ground.
Keep base cations in balance. Dragon PureCal supplies calcium at a neutral pH, Dragon MagiCal provides magnesium with calcium, and Dragon PotaMax covers potassium, which banana removes in very large quantities. The guide to banana fertigation and potassium covers the crop’s potassium demand in detail.
Choose the nitrogen form deliberately. Weight the programme toward nitrate nitrogen rather than relying heavily on ammonium and urea.
Do not blanket-apply iron or manganese. Apply them only where a soil or leaf test shows a real shortage. For zinc, Dragon Zinc corrects a confirmed deficiency without adding the others.
Support soil organic matter. Humic products such as Dragon HV15 and Dragon PK Humic support the root environment on soils where organic matter is low. Ecuador has also been expanding the use of Trichoderma and other biological agents as part of integrated management.
Fertilizer and biosecurity
There is one place where fertilizer suppliers carry a direct responsibility for TR4, and it is not the product. It is how the product arrives.
A delivery truck that drives from farm to farm can carry infested soil on its tyres. Sacks reused between farms can carry soil inside and out. Bulk or repacked fertilizer handled in the open can pick up soil along the way. Every one of these is a route by which the disease can move.
Practical rules for any farm receiving inputs:
- Receive deliveries at the farm boundary or at a disinfection point, not inside production areas.
- Do not let supplier vehicles drive into the plantation.
- Accept fertilizer only in intact factory packaging, and refuse reused or visibly soiled sacks.
- Keep delivered inputs on clean hard standing, off bare soil.
- Follow Agrocalidad’s disinfection protocols for people, tools and vehicles.
These measures cost almost nothing and protect far more than any nutrient programme can.
Black Sigatoka has not gone away
TR4 has taken the headlines, but black Sigatoka remains the disease that costs Ecuadorian growers money every week. It destroys leaf area, and banana needs enough healthy leaves at flowering to fill the bunch properly.
Sigatoka is controlled through a fungicide programme and the removal of infected leaves. Nutrition plays the same supporting role here as with TR4: a plant with adequate potassium and balanced nutrition produces and retains functional leaves better than a stressed one, which helps it carry a full bunch through the disease pressure. It does not control the disease.
Lessons from the region
Colombia’s experience since 2019 is the closest guide. The disease spread from La Guajira into Magdalena and has affected a number of large commercial export farms, despite containment efforts. What slowed it was biosecurity discipline, not inputs.
Peru and Venezuela have followed. Ecuador arrived later than its neighbours, which gave the industry time to prepare, and the speed of its containment response reflects that.
What this means for a distributor
Fertilizer dealers in El Oro, Los Rios, Guayas and the other banana provinces now have a responsibility that goes beyond selling product. The most useful things a dealer can do are to refuse to overclaim, to deliver in a way that respects farm biosecurity, and to help growers test their soils before spending.
A dealer who tells a grower honestly that no bag of fertilizer stops TR4, and then helps them run a sound, test-based programme and a clean delivery protocol, will keep that grower’s trust long after the sellers of miracle products have been found out.
Dragon Ferti supplies Certificates of Analysis, Technical Data Sheets, Safety Data Sheets and Free Sale Certificates, and manufactures under ISO 9001, ISO 14001 and ISO 45001 certified management systems. Every product is free of chloride, sodium and heavy metals. Ecuador’s cacao growers face a different soil question, covered in the guide to cadmium in cacao and the EU limits.
Conclusion
Fusarium TR4 is now in Ecuador, it cannot be removed from infested soil, and no fertilizer prevents or cures it. Biosecurity is the defence. Within that, evidence does support sound soil and nutrition practice as part of plantation health: correcting acidity, keeping calcium, magnesium and potassium in balance, favouring nitrate nitrogen, building organic matter and avoiding unnecessary iron and manganese. Report any suspicious symptoms to Agrocalidad on 1800 247 600. For specifications or distribution enquiries, see the Dragon Ferti range or contact the export team through the contact page.
Frequently asked questions
When was Fusarium TR4 confirmed in Ecuador?
A suspected case was registered on 3 September 2025 on a farm in Santa Rosa, El Oro, and Agrocalidad and the Ministry of Agriculture confirmed it on 18 December 2025, declaring a six-month phytosanitary emergency. A second case was confirmed on a neighbouring property in July 2026.
Can fertilizer prevent or cure Fusarium TR4 in banana?
No. No fertilizer, biostimulant or soil amendment prevents or cures TR4, and infested soil cannot be cleaned. Biosecurity to prevent the movement of infested soil and plant material is the primary defence.
Does soil nutrition affect Fusarium wilt?
Research links higher soil pH, adequate calcium, magnesium and potassium, more organic matter and a higher share of nitrate nitrogen with lower disease severity, and higher iron and manganese with greater severity. These are supporting practices for plantation health, and researchers have concluded that soil chemistry alone will not prevent disease build-up.
Can fertilizer deliveries spread TR4?
They can if handled carelessly. Vehicles, reused sacks and fertilizer handled in the open can carry infested soil between farms. Receiving deliveries at the farm boundary, keeping supplier vehicles out of production areas and accepting only intact factory packaging reduce the risk.
Is Ecuadorian banana safe to eat after TR4 was detected?
Yes. Agrocalidad has stated that the disease poses no risk to human health and that the fruit does not carry it. TR4 affects the plant, not the safety of the banana.