UC Davis, Vegetable Research and Information Center
VIRUS PROBLEMS IN CUCURBIT
By Dr. Rebecca Creamer, UCR Plant Pathologist
The following table is supplied by Dr. Creamer, UCR plant pathologist, to help explain the complex web of
viruses that affect cucurbits. The table lists the virus as well as their host range and vectors. The table is a
summary from Dr. Crearner's presentation on viruses at a cucurbit workshop in Riverside May 28,1998.
Overview of insect vectors and virus transmission modes
Target Crop
Group
Squash mosaic
comovirus
Cucurbit aphid borne
Squash leaf curl
luteovirus
Beet curly top
geminivirus
narrow host
range minimal
narrow host
range
narrow host
range
broad host range
Lettuce
infectious
yellows
Cucurbit yellow
stunting disorder
Beet pseudo
yellows
Cucumber
mosaic
closterovirus
broad host range
no CA losses
closterovirus
not in CA
closterovirus
narrow host
range
broad host range
cucumovirus
broad host range
moderate CA losses
Zucchini yellow
mosaic
potyvirus
narrow host
range
large CA losses
Watermelon
mosaic
Papaya ringspot
potyvirus
moderate host
range
narrow host
range
moderate CA losses
geminivirus
potyvirus
Host Range
Severity of losses
in California
CA losses and
incidence
unknown CA losses
no CA losses
some CA losses
minimal CA losses
minimal CA losses
Transmission mode
Transmitted by seed and
beetles, control by clean seed
Persistent transmission by
aphids
Persistent whitefly transmission
(sweetpotato whitefly)
Persistent leafhopper
transmission (beet leajhopper)
Semi-persistent whitefly
transmission (sweetpotato
whitefly)
Transmitted by sweetpotato
and silverleaf whiteflies
Transmitted by greenhouse
whitefly
Transmitted non-persistently by
aphids - green peach and
cotton- melon aphids
Transmitted non-persistently by
aphids - green peach and
cotton- melon aphids
Control ZYMV by removing
infected source weeds,
insecticides don't work, no good
resistance for ZYMV yet
commercial