Divisi
Ganoderma basal stem rot
Ganoderma boninense · Fungal
Photo: Edward L. Barnard, Florida Department of Agriculture and Consumer Services · CC BY 3.0
Ganoderma basal stem rot (caused by the white-rot fungus Ganoderma boninense) is a slow, lethal disease of oil palm and coconut. It quietly rots the base of the trunk and the roots for years before you can see anything, then kills the palm. It spreads underground from old infected stumps and roots touching healthy roots, and through the air by spores that settle on wounds and dead wood.
Bob Peterson (Flickr) · CC BY-SA 2.0 
This image was created by user chuah at Mushroom Observer, a source for mycological images.You can contact this user here. · CC BY-SA 3.0
Why it matters
This disease can kill outright, so a bad outbreak can take half your palms (up to 50%) — and a dead oil palm or coconut is years of income gone, not one lost season. It is so hard to beat because the fungus rots the trunk from the inside for years before you see a single sign; by the time a bracket (shelf) fungus appears on the trunk, the base is already destroyed and that palm cannot be saved. There is no spray that cures it — once it is in your soil it lives on in old roots and stumps and infects the next palms. Your only real power is to stop it spreading and to keep it out when you replant.
When to act
any palm with a bracket fruiting body at the stem base, or unopened spear leaves with a flattened, pale canopy
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 ganoderma basal stem rot field guide
- Identify it
- Scout for it
- Control it
15 field-guide sections in the app
The full guide to ganoderma basal stem rot — 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 ganoderma basal stem rot?
The first thing you see is in the crown, not the trunk. The palm looks thirsty even when the soil is wet: older, lower fronds turn pale then yellow, dry out and collapse to hang down like a skirt around the trunk. At the top, several spear leaves (the young unopened fronds) stay shut and stand stuck upright instead of opening, and the whole canopy looks flat, thin and pale.
When should I take action against ganoderma basal stem rot?
any palm with a bracket fruiting body at the stem base, or unopened spear leaves with a flattened, pale canopy
How do I control ganoderma basal stem rot?
Prevent it first — this is your strongest tool (sanitation). Before you replant, dig out and destroy every old stump and big root of the previous palms; do not leave them buried, because the fungus lives on in that dead wood for years and infects the new palms through the soil. Never plant a new palm straight into an old infected site without clearing it first.
Which crops does ganoderma basal stem rot affect?
Among the crops covered here: Coconut, Oil palm.
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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