Leaf curl virus
Curled, crinkled, cupped leaves and a stunted, bushy plant that stops flowering — a whitefly-spread virus stopped by managing the whitefly.
- Pathogen
- Virus (begomovirus complex)
- Spreads by
- Whitefly (Bemisia tabaci)
- Favoured by
- High whitefly numbers; warm, dry weather
- Main risk
- Stunting; little or no flowering/fruiting
Overview
Leaf curl is a group of begomoviruses spread by the whitefly (Bemisia tabaci) that severely affect chilli, tomato, cotton and several other crops (chilli leaf curl, tomato leaf curl, cotton leaf curl and related viruses). Infected leaves curl upward or downward, crinkle, cup and thicken, with cleared or swollen veins; the internodes shorten so the plant becomes stunted and bushy, and enations (small leafy outgrowths) may appear on the underside of veins in some crops.
A plant infected early is badly stunted and largely stops flowering and fruiting, so early infection is devastating to yield in chilli, tomato and cotton. The virus is not seed- or contact-spread and cannot be cured or sprayed out — spread depends entirely on the whitefly. Control therefore combines resistant/tolerant varieties, protecting the nursery and early crop from whitefly, roguing infected plants, and removing weed and volunteer hosts that hold the virus.
How to identify it
- Leaves curling upward or downward, crinkling, cupping and thickening, with cleared or swollen veins.
- Shortened internodes so the plant becomes stunted and bushy.
- Little or no flowering and fruiting in early-infected plants; small, deformed fruit if any.
- Enations (small leafy outgrowths) on the underside of veins in some crops (e.g. cotton).
What causes it and when
- A complex of begomoviruses spread only by the whitefly (Bemisia tabaci) — not by seed or by touch.
- Whiteflies acquire the virus from infected plants and weeds and carry it to healthy plants, so spread tracks whitefly numbers.
- Favoured by high whitefly populations and warm, dry weather, and by nearby infected crops and weed hosts.
- Early (nursery/seedling) infection is by far the most damaging.
Cultural & organic control
- Grow resistant/tolerant varieties where available — the most effective control.
- Raise nursery under insect-proof net and use only healthy, virus-free seedlings; protect the early crop from whitefly.
- Rogue out and destroy infected plants early, and remove weed and volunteer hosts that carry the virus.
- Use yellow sticky traps and border/barrier crops, and encourage natural enemies of whitefly.
Chemical (vector) control
- Since the virus cannot be sprayed, target the whitefly — protect the nursery and early crop before spread begins.
- Use CIB&RC-registered insecticides for whitefly judiciously (rotating groups) with traps and natural enemies.
- An early systemic/seed-treatment against whitefly can delay spread in the critical early stage where recommended.
- Confirm the current whitefly-management schedule for your crop with your local KVK.
Prevent it coming back
- Make resistant varieties, net-protected nurseries and early whitefly management the routine.
- Remove weed and volunteer hosts between crops to cut the virus reservoir.
- Rogue infected plants as soon as seen and avoid a continuous overlap of susceptible crops.
Crops most at risk
Where this problem is called out in our crop guides — open a crop for the full package of practices.
Frequently asked questions
My chilli/tomato leaves are curling, crinkling and the plant is stunted and bushy. What is it?
That upward/downward curling, crinkling and cupping of the leaves with a stunted, bushy plant that barely flowers is leaf curl virus, spread by the whitefly. It is worst when plants are infected early. The virus cannot be cured or sprayed out, so grow a resistant variety, raise the nursery under net, manage the whitefly early with traps and judicious insecticide, rogue infected plants, and clear weed hosts.
Will spraying insecticide cure a leaf-curl-infected plant?
No — once a plant has the virus, no spray reverses the curling or restores flowering; that plant is best rogued out. Insecticide against the whitefly is worthwhile only to protect still-healthy plants from getting infected, especially in the nursery and early crop. So the aim of vector control is prevention of spread, not cure — combine it with resistant varieties, net-protected nurseries, and removing infected plants and weed hosts.
Why is protecting the nursery so important for leaf curl?
Because early infection is the most damaging: a seedling that catches leaf curl is badly stunted and often never flowers or fruits properly, losing almost all its yield. Raising the nursery under insect-proof net and transplanting only healthy, virus-free seedlings keeps the whitefly and the virus away during that critical early window, which is one of the most effective steps against leaf curl in chilli and tomato.
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.