1. Entry into the Tree
- Fungi enter through wounds, branch cuts, or injection points
- The tree detects the physical intrusion and foreign material
Key Idea: The tree senses that “something living is invading.”
2. Recognition of Pathogens
- Tree cells recognize fungal molecules (like chitin and glucans in cell walls)
- These molecules are called PAMPs – Pathogen-Associated Molecular Patterns
- Recognition triggers immune signaling inside the tree
Effect: The tree knows a living threat is present and prepares defense.
3. Activation of Defense Pathways
Fungal invasion stimulates multiple chemical signaling pathways:
- Jasmonic acid (JA) pathway: activates wound and defense responses
- Salicylic acid (SA) pathway: coordinates antimicrobial defenses
- Ethylene signaling: helps control stress response and resin secretion
Effect: Defense genes are turned on; enzymes start producing defense compounds.
4. Production of Antimicrobial Compounds
- Tree produces compounds to fight the fungus:
- Sesquiterpenes → aromatic oils
- Chromones → resinous compounds
- These compounds accumulate in wood tissue around the fungus
Effect: The tree is protecting itself, and this accumulation is the resin.
5. Resin Deposition
- Resin is secreted into xylem tissue, surrounding fungal colonies
- Darkens and hardens over time
- Stops fungus from spreading uncontrolled
Effect: Wood becomes aromatic, dense, and marketable.
6. Continuous Stimulation
- Living fungi remain active in the tree
- Tree maintains long-term defense response
- Resin continues forming in layers and veins
Effect: Creates high-quality, deep resin, suitable for oud oil extraction.
7. Resulting Benefits
| Effect | Benefit |
|---|---|
| Deep resin veins | High-grade agarwood |
| Complex aromatic compounds | Premium oud fragrance |
| Sustained resin production | Greater yield per tree |
| Localized defense | Tree remains healthy |
One-Line Farmer Version
Fungi “trick” the tree into thinking it is under attack, so the tree produces aromatic resin to defend itself.