Cucumber Mosaic Virus

Cucumber Mosaic Virus (CMV)

Cucumber mosaic virus
Cucumber mosaic virus [Credit: DieterO]
Cucumber mosaic virus
Cucumber mosaic virus [Credit: William M. Brown Jr. - USDA Forest Service]
Cucumber mosaic virus
Cucumber mosaic virus [Credit: Scot Nelson]

Host Plants:

On Crops: Cucumbers, squash, pumpkin, spinach, lettuce, peas, and many flowers and weeds

Where Found:

Mostly in warm temperate climates, where CMV is transmitted by aphids


Leaves become brittle and puckered, with patches in different shades of yellow and dark green. Fruits have kinks, puckered spots or are not fully formed, and tend to taste bitter.


Like other plant viruses, cucumber mosaic virus interferes with genetic signaling within the plant. Leaves that are distorted by the virus cannot function normally, so plants struggle to grow and stop gaining size. The yellow patches on leaves turn to brown as the disease advances.

Preventing Problems:

Choose resistant varieties, which are widely available. Measures that reduce aphid populations will cut the risk of CMV and other viral diseases in the garden. Grow plenty of nectar-producing flowers to attract aphid predators including ladybeetles, lacewings and hover flies. If viral diseases are common in your garden, use row covers (garden fleece) to protect young plants from aphids.

Managing Outbreaks:

To keep aphids from spreading CMV to other plants in your garden, pull up infected cucumber or squash plants and compost them in an active compost pile. If an entire planting is infected, also dispose of any unused seeds, because it is possible that the seeds were infected with the virus.

< Back