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 combines readily with potato virus x (PVX) and Y (PVY). When this happens, losses can be catastrophic. 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, each with slight variations in symptoms and behaviors. Diagnosis can be difficult. This viral disease is spread by infected seed potatoes, mechanically, and 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 bring PVA into your potato patch.

PVA symptoms

Symptoms of potato virus A are faint and easily 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. Complete leaf death may occur, depending on the cultivar, the degree of infection, and environmental conditions.

PVA management

The best way to prevent this disease in your garden is to only plant certified pest- and disease-free, PVA-resistant seed potatoes. After that, control aphid populations as well as you can. As any gardener knows, aphids are highly prolific. You can reduce their numbers by applying minimal amounts of nitrogen, planting as early in the season as possible, and monitoring for vanguards. A single aphid can become thousands of aphids in a few short days.

Remove infected plants and throw them in the garbage bin. As always, disinfect your garden tools regularly with a household 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.