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Tomato Diseases | Cucumber Mosaic Virus

Cucumber Mosaic Virus

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  • Light and dark green mosaic patterns on the foliage.
  • Yellow spotting or streaking on the leaves and veins.
  • A reduction of leaf blade area along the main vein (filiformity) of the leaf; symptomatic leaves are described as “rat-tail-” or “shoestring-” like.
  • Oak leaf pattern and necrotic spots surrounded by a yellow halo (pepper)
  • Necrosis of stems (pepper)

CMV_TomatoGhanaOct2012 copy 50QUALITY CMVpepperLeafShock copy 50QUALITY CMCpepperleaf3 copy 50QUALITY
Foliar symptoms of CMV on tomato plants (left) and pepper plants (middle and right).


  • Internal browning of fruit.
  • Poor yield and poor quality fruits with delayed fruit ripening.
  • Reduced fruit size and wall thickness (peppers)

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CMV symptoms on pepper and jalapeño pepper.

Favorable Environmental Conditions

  • Conditions that support aphid movement and feeding promote spread of the disease.
  • Temperatures between 70-85ºF; anything warmer or colder than this range slows down the reproduction of the aphids.
  • Stressful conditions for the plants also cause stress on the vectors.

Often Confused With

Scouting Notes

  • Scout the high tunnels and diseased plants and remove and destroy the infected plants.
  • Monitor aphid populations early in the season and apply insecticides if needed.