WSU Extension


Cucumber, Pumpkin, Squash
Angular leaf spot 
Cucumber mosaic virus 
Curly top (Beet curly top virus) 
Pollination failure 
Powdery mildew 
Root rot 
Verticillium wilt 
White mold 
Brown marmorated stink bug 
Spider mites 
Squash bug 
Western spotted cucumber beetle 

print version| pdf version| email url    
Cucumber, Pumpkin, Squash : Cucumber mosaic virus
(revision date: 6/3/2014)

Cucumber mosaic is a viral disease of cucumbers, melons, squash, and other plants. It is spread primarily by aphids, but can also be transmitted by mechanical means, infected seed, and by cucumber beetles. The early symptoms may be limited to downward leaf curling, yellow and green mosaic patterns on leaves, and reduced leaf size. Other typical symptoms include plant stunting, leaves that are yellow, mottled, and wrinkled, and deformed plant parts. Fruit produced by affected plants may have warty bumps and blotchy coloration. These fruit are usually bitter in flavor. This virus has a very wide host range, including many vegetables, ornamental flowers, woody plants, and weeds. Other viruses, such as Zucchini Yellows Mosaic Virus and Watermelon Mosaic Virus, can also cause mosaic symptoms in squash.
Management Options

Non-Chemical Management
  • Plant resistant or tolerant varieties. 'Niagara' cucumber is resistant, while the cucumber varieties 'Burpee', 'Dasher II', 'Gemini', 'Marketmore', 'Multipik', 'Pioneer', and 'Surecrop', among others, are tolerant. The pickling cucumber 'Pioneer' has high tolerance.
  • Control aphids and cucumber beetles.
  • Control weed hosts such as wild cucumber, milkweed, and others in and around the garden.
  • Remove and destroy infected plants.
Select non-chemical management options as your first choice!

Chemical Management

None recommended


+ Show larger images