Citrus foot rot and gummosis
Dark sticky gum oozes from cracked bark near the base of the trunk, the bark underneath turns brown and rots, and the canopy yellows and thins.
Crops it strikes
What you see
When to act
Each month in the rains and after every flood, look at the trunk base of each tree, above all in the first 2 years. Act on the first patch of gum or dark wet bark.
What to spray
Active ingredients only, never brands. The FRAC group tells how it works: switch to a different group next time, so the disease does not learn to survive it. Spray only when the damage is worth the cost, and only with products registered with the Fertilizer and Pesticide Authority for your crop. Follow the label. The Shopee and Lazada links only show who sells something with that active ingredient, not a recommendation of any seller or product.
Resistance: Water molds learn to resist metalaxyl (group 4) quickly when it is used alone. Rotate it with fosetyl (P07), copper or fluopicolide (43).
How to prevent it
- Plant on well drained ground or on mounds and dig drains. Citrus collars rot in standing water.
- Use seedlings budded high on a tolerant rootstock, so rain splash from the soil does not reach the scion bark.
- Keep grass, mulch and soil off the trunk base, and avoid hoe and brush cutter wounds there.
- Prune low branches to about 1 meter above the soil, so splash and damp stay off the leaves and fruit.
- Scrape a gumming patch to clean wood in dry weather and paint it with copper paste. Burn the scrapings.
- Water at the base without wetting the trunk, and never let water pool around it.
Natural enemies and biological help
- Trichoderma in compost around the root zone helps hold soil water molds down. It does not cure trunk cankers.
Not sure it is this one?
Many diseases look alike. Send a photo to Anee, the smart farm technician in anee.io. She reads it with your crop, its age and the weather, and tells you what it most likely is and what to do first. In Tagalog or English.