Verticillium wilt
One-sided or scattered wilting with olive-brown streaked wood inside the stem — a soil-borne fungus with no cure once a tree is infected.
- Pathogen
- Verticillium dahliae (soil fungus)
- Spreads by
- Infested soil, water, tools, infected nursery stock
- Favoured by
- Land recently under cotton, tomato, potato, chilli
- Main risk
- One-sided wilt, internal wood staining, tree decline
Overview
Verticillium wilt is caused by the soil-borne fungus Verticillium dahliae, which infects through the roots and grows up into the tree's water-conducting (vascular) tissue, physically blocking the flow of water and causing wilting even when the soil is moist. It typically shows as one-sided or scattered wilting and yellowing of leaves and shoots — often starting on just one branch or one side of the tree rather than the whole canopy at once. Cutting across an affected branch or the trunk shows a brown-to-olive discoloration in the wood just under the bark, the clearest confirming sign.
The fungus survives in the soil for many years as resting structures, without needing a live host plant, and it has an unusually wide host range that includes cotton, tomato, potato, chilli, brinjal and many other common field and vegetable crops — land that recently grew any of these is a real risk for a newly planted tree. There is no effective in-tree cure once infection is established, since fungicide sprays cannot reach or clear the pathogen from inside the vascular tissue, so management is entirely about avoiding infested ground, using certified disease-free planting material, and general orchard sanitation.
How to identify it
- Wilting and yellowing that is one-sided or scattered — often just one branch or one side of the tree, not the whole canopy together.
- Cutting across an affected shoot, branch or the trunk shows brown-to-olive discoloration in the wood just under the bark.
- Affected shoots can die back, or the whole tree can decline slowly over one or more seasons.
- Symptoms can appear even when the soil is adequately moist, since the block is inside the plant's own water-conducting tissue, not a lack of water in the soil.
What causes it and when
- The soil-borne fungus Verticillium dahliae, which infects through the roots and colonises the vascular tissue.
- Survives in soil for years as resting structures even without a host crop present, so old infested ground stays risky for a long time.
- Has an unusually wide host range — cotton, tomato, potato, chilli, brinjal and other common crops are all hosts, so a field's recent cropping history matters.
- Spreads through infested soil, irrigation water, contaminated tools, and infected nursery/planting material.
Cultural & organic control
- Check the planting site's cropping history and avoid ground recently under cotton, tomato, potato, chilli or other known host crops.
- Source only certified, disease-free grafted plants from a reputable nursery, and inspect roots before planting.
- Avoid moving soil, irrigation water or tools between an infested block and a clean one.
- Keep trees generally vigorous and unstressed, since stressed trees decline faster once infected.
Chemical control
- There is no effective fungicide cure once a tree is infected — sprays cannot reach the pathogen inside the vascular tissue.
- Management is entirely preventive: site selection, clean planting material and sanitation, not a treatment applied after symptoms appear.
- Where a valuable tree is affected, remove and destroy it to limit further soil contamination rather than attempting to treat it.
- Confirm any locally recommended soil fumigation or biofungicide practice for high-value new plantings with your local KVK or research station.
Prevent it coming back
- Never plant a new orchard on ground with a recent history of cotton, tomato, potato, chilli, brinjal or other known hosts without a long rest or rotation first.
- Buy only certified, disease-free grafted plants, and keep separate tools and equipment for known-infested blocks.
- Remove and destroy severely affected trees, including as much of the root system as practical, to reduce the soil-borne fungus load.
- This is a globally serious disease for many tree and orchard crops; treat site selection as the single most important prevention step, since there is no cure once a tree is infected.
Crops most at risk
Where this problem is called out in our crop guides — open a crop for the full package of practices.
Varieties to consider
Named seed varieties whose resistance or susceptibility to this problem is documented on their own variety page.
Frequently asked questions
Why is only one branch or one side of my tree wilting, when the rest looks healthy?
That one-sided pattern is a classic sign of Verticillium wilt. The fungus blocks the water-conducting tissue feeding whichever roots and branches it has reached first, so wilting often shows on one side before the whole tree is affected. Cut across a wilting branch — brown-to-olive staining in the wood just under the bark confirms it.
Can I cure a tree once Verticillium wilt is confirmed?
No — there is no effective fungicide that reaches or clears the fungus once it is established inside the tree's vascular tissue. Management is entirely preventive: avoid planting on infested ground in the first place, use certified disease-free planting material, and remove a badly affected tree to limit the soil-borne fungus spreading further.
Why does it matter what crop grew on my land before I plant a tree there?
Verticillium dahliae has an unusually wide host range that includes cotton, tomato, potato, chilli and brinjal, and it survives in the soil for years even without a host crop present. Land that recently grew any of these common crops carries a real risk of already being infested, so checking cropping history before planting a susceptible tree is one of the most effective prevention steps available.
Symptoms and control measures follow ICAR, KVK and state agricultural-university package-of-practices; any named chemical is a registered use. Always read the product label and confirm the dose for your crop and zone. editorial policy.