World Vegetable Center
Symptoms vary widely. One of the most common
expressions is a severely stunted, nonproductive plant
that has dull light green foliage with a leathery
appearance but not distinctive foliar markings.
In some cases the leaves become narrow and no
longer expand, while in other cases, small necrotic
specks or ring spots with oak leaf patterns develop.
Sometimes a necrotic line develops across the leaf.
Affected leaves may drop prematurely. Older plants that
are infected may show foliar mottling or no symptoms
on foliage or fruit.
Fruit may be wrinkled, bumpy, pale to yellowish
green in color, sometimes with sunken lesions. On
some varieties lines or ring spots may develop.
Conditions for Disease Development
Cucumber mosaic virus (CMV) is not transmitted
through pepper seed. CMV can be mechanically
transmitted but because it is not as stable as TMV,
workers handling infected pepper plants do not as
readily transmit it.
More than 80 species of aphids including the green
Stunted, pale plant with no
distinctive leaf markings
How to Identify Cucumber Mosaic Virus
Written by Ray Cerkauskas, Visiting Scientist from Agriculture and Agri-Food Canada. Edited by Tom Kalb. Photos by S.K. Green, L.L.
Black and T.A. Zitter. Published by AVRDC – The World Vegetable Center; P.O. Box 42, Shanhua; Taiwan 741; ROC
tel: (886-6) 583-7801; fax: (886-6) 583-0009; email: firstname.lastname@example.org; www: www.avrdc.org
Chlorotic and necrotic ringspots
and lines on foliage and fruits
peach aphid, Myzus persicae, are an vector of CMV;
weeds are hosts for the virus as well as for the aphid
vectors. The large number of aphid vector species and
natural host reservoirs accounts for the high incidence
of CMV in field plants.
Aphid vectors can acquire and transmit the virus
after feeding for only one minute, but the ability to
transmit it declines quickly. Pepper is not a preferred
host of the green peach aphid, which normally p