Apical leaf curl virus (potato)
Top leaves curl upward and turn stiff, the plant looks stunted and bushy, and tubers come out fewer and smaller — a whitefly-spread geminivirus with no cure once infected.
- Pathogen
- Geminivirus (whitefly-transmitted)
- Spreads by
- Whitefly (Bemisia tabaci); infected seed tubers
- Favoured by
- Warm weather; high whitefly numbers; late planting
- Main risk
- Stunting; fewer, smaller tubers
Overview
Potato apical leaf curl virus, often called simply "Gemini virus" by growers, is caused by a geminivirus spread mainly by the whitefly (Bemisia tabaci) and carried over in infected seed tubers. Infected plants show upward curling and puckering of the topmost leaves, which turn stiff and leathery, and the whole plant looks stunted and bushy with shortened internodes near the top. Small aerial tubers sometimes form in the leaf axils of infected plants — an unusual but telltale sign.
Whitefly numbers build up in warm weather, so late-planted or off-season potato crops that overlap with peak whitefly activity are hit hardest, and infection early in crop growth causes more stunting and yield loss than infection late in the season. There is no cure once a plant is infected — control rests entirely on keeping whitefly numbers down, planting on time with clean certified seed, and choosing a tolerant variety in a known-risk area.
How to identify it
- Upward curling and puckering of the topmost (apical) leaves, which also turn stiff and leathery.
- Whole plant looks stunted and bushy, with shortened internodes near the top.
- Small aerial tubers sometimes form in the leaf axils on infected plants — an unusual but telltale sign.
- Tubers from infected plants are fewer and smaller, cutting yield; symptoms usually show up from about a month after planting onward.
What causes it and when
- Caused by a geminivirus, spread mainly by the whitefly (Bemisia tabaci) feeding on the crop, and carried over in infected seed tubers.
- Whitefly numbers build up in warm weather, so late-planted or off-season potato crops that overlap with whitefly buildup are hit hardest.
- Infection early in crop growth causes more stunting and yield loss than infection late in the season.
- Risk became a serious concern in parts of Punjab and Gujarat after major whitefly outbreaks; it varies by region and season.
Cultural & organic control
- Plant on time within the recommended local window — avoid late planting that pushes the crop into peak whitefly season.
- Use only healthy, certified seed tubers, since infected tubers carry the virus into the new crop.
- Rogue out (remove) plants showing early apical curling symptoms so they don't become a whitefly source for the rest of the field.
- Put up yellow sticky traps around the field to monitor and help reduce whitefly numbers.
Chemical / seed treatment
- There is no cure for an already-infected plant — control is entirely about keeping the whitefly vector down and using clean seed.
- Spray a recommended insecticide against whitefly at the first sign of buildup, following the label dose and pre-harvest interval.
- Some varieties (Kufri Bahar, for instance) are noted as tolerant to this virus and are a useful option in a known-risk area — confirm current tolerant/resistant options with your KVK.
- Where possible, avoid growing potato right next to or right after a whitefly-prone crop such as cotton or tomato.
Prevent it coming back
- Plant within the recommended local window and always use certified, healthy seed tubers.
- Keep whitefly numbers down through the season with monitoring, traps and timely spray, and rogue out symptomatic plants early.
- Where the risk is known to be high, prefer a tolerant variety.
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
My potato plants have curled, stiff top leaves and look stunted — what is it?
This sounds like apical leaf curl virus (often called Gemini virus), spread mainly by whitefly and by infected seed tubers. There is no cure once a plant is infected — the useful steps are controlling whitefly with a recommended spray, roguing out symptomatic plants, and using clean certified seed and, where the risk is known, a tolerant variety like Kufri Bahar.
How does this virus spread to my crop?
Mainly two ways: the whitefly (Bemisia tabaci) feeding on the crop carries the virus from plant to plant, and infected seed tubers carry it straight into a new crop. Risk is highest when potato is planted late enough to overlap with peak whitefly activity in warm weather, so timely planting is one of the simplest ways to cut exposure.
Is there any potato variety that resists this virus?
Kufri Bahar is noted as tolerant to Gemini virus on our variety page, which is a useful option if you farm in a known-risk area. Combine variety choice with whitefly control (monitoring, sticky traps, timely spray) and clean certified seed for the best result, since no variety alone fully removes the risk.
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.