Potato Virus A

For lack of a better name, potato virus A (PVA) can infect more than just potatoes. Eggplant, peppers, and tomatoes are also susceptible.


Potato virus A is usually a mild problem, but it can cause crop losses of up to 40%. This disease is worldwide, and it combines readily with potato virus x (PVX) and potato virus y (PVY). When this happens, losses can be catastrophic. In the world of potato viruses, PVA is ranked 5th behind potato leafroll, PVY, PVX, and PVS.

Potato plant with viral infection (Rasbak) CC BY-SA 3.0

The PVA virus

This little potyviral RNA strand is tricky. There are many different strains, and each one has slightly different symptoms and behaviors. This can make diagnosis difficult. This viral disease is spread by infected seed potatoes, mechanically, and by aphids. Once infected, aphids carry the potyvirus in their gut. As they feed, they spread the disease through their saliva. Your shoes, clothing, and garden tools can also carry PVA into your potato patch.


PVA symptoms

Symptoms of potato virus A are faint and can easily be missed. Mild leaf crinkling and yellow mottling might be all you see. If you look more closely, you may see these other symptoms:

• Rough leaf texture
• Smaller than normal leaflets
• Stunting
• Sunken veins
• Wavy leaf margins

Stems of infected plants commonly bend outward from the center, giving them a bushier appearance. Depending on the cultivar, the degree of infection, and environmental conditions, complete leaf death may occur.


PVA management

The best way to prevent this disease from occurring in your garden is to only plant certified disease-free seed potatoes with a reputation for being resistant to PVA. After that, control aphid populations. As any gardener knows, aphids are highly prolific. You can reduce their numbers by avoiding the use of excess nitrogen, planting as early in the season as possible, and monitoring for vanguards. A single aphid can turn into thousands of aphids in a few short days.


Infected plants should be removed immediately and thrown in the garbage bin. As always, disinfect your garden tools regularly with a bathroom cleaner.

Homegrown potatoes make lovely patio plants (Kate Russell)

And don’t let the threat of disease stop you from trying your hand at growing potatoes at home. They are easy to grow and taste delicious.