Pea Seed-Borne Mosaic

If you grow peas or lentils, watch for pea seed-borne mosaic. The same is true for fava beans and chickpeas.

Purple-podded peas (Kate Russell)

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Sadly, I was unable to find any freely available photos of pea seed-borne mosaic, so you will have to search for your own images. The purple-podded peas pictured above are perfectly healthy.

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Symptoms of pea seed-borne mosaic

Stunting, deformation, and rosette-type growths at the ends of stems are all signs of pea seed-borne mosaic. Chlorosis, downward cupping, vein clearing and swelling, and the classic mosaic or mottling of mosaic diseases may all be present in infected plants. Vein clearing is a common symptom of viral infections. Vein clearing describes how leaf veins appear translucent. Seeds shrivel and become discolored.


Pea seed-borne mosaic infection is easily mistaken for chemical overspray, nutrient toxicities, and water stress. Laboratory tests are needed to verify this infection. You can often take ziplock bagged samples to your local Department of Agriculture for analysis.


How to control pea seed-borne mosaic

The pea seed-borne mosaic virus (PSbMV) is carried to your garden by aphids. Do the best that you can control them. Remove any plants infected with pea seed-borne mosaic and dispose of them in the trash. Unfortunately, some infected plants will never show symptoms. As aphids feed on these asymptomatic plants, they then carry the disease to nearby plants, spreading infection. For the most part, as the name implies, this viral disease is carried by infected seeds. Plant infected seeds and the aphids do the rest. The only way to prevent pea seed-borne mosaic from occurring in your garden is to buy certified pest- and disease-free seeds.


This disease can overwinter in nearby weeds, such as shepherd’s purse, vetches, and black medic. If you notice outbreaks of pea seed-borne mosaic, and you know your seeds were clean, look at what is growing nearby.


You can prevent pea seed-borne mosaic by planting resistant varieties.