Citrus canker
Raised corky brown spots with a yellow ring and an oily, glazed edge appear on leaves, twigs and fruits.
Crops it strikes
What you see
When to act
Check new flushes and young fruit every week or two in the rains, more after storms. Act when the first raised corky spots with a yellow ring show on young leaves or fruit: prune them out in dry weather and protect the next flush and the young fruit.
What to spray
- Copper hydroxideFRAC M01ShopeeLazada
- Cuprous oxideFRAC M01ShopeeLazada
- Bordeaux mixtureFRAC M01ShopeeLazada
- Bacillus amyloliquefaciensFRAC BM02ShopeeLazada
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.
How to prevent it
- Plant canker free seedlings from a clean nursery, and do not bring in budwood or seedlings from sick orchards.
- Plant windbreaks around and across the orchard. Wind driven rain spreads canker and makes the wounds it enters.
- Prune and burn twigs with canker in dry weather, and clean the shears between trees.
- Keep citrus leafminer down on new flushes. Its tunnels let canker in.
- Stay out of the orchard while the trees are wet, and water at the base instead of over the leaves.
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.