Curly Top Virus & Cucumber Mosaic Virus

Curly Top Virus

Jeff Schalau, Yavapai County Cooperative Extension Agent has identified cucumber mosaic virus and curly top virus as affecting vegetables in the Verde Valley.  You can get more information by checking out this “Backyard Gardening” article.  (August 1, 2012)

http://cals.arizona.edu/yavapai/anr/hort/byg/archive/curlytopvirus2012.html

Beet leafhoppers are the source of curly top virus and are common in our area.  When a plant is infected the leaves pucker and are stunted.  The leaves curl and roll upward and the main leaf petiole curves downward.  Leaves look leathery and the veins turn purple while the areas between the veins yellow. 

Cucumber Mosaic Virus

Cucumber mosaic virus can infect tomatoes also.  Aphids spread the virus.  Leaves become mottled and yellow.  New leaves become twisted and curl downward and develop a “shoestring” look.  Plants become stunted and produce only small quantities of fruit.

In both cases once the problem is identified, the plants should be removed immediately.  Do not compost the plants.  The viruses are not carried in the soil so you can replant where the disease plant was growing.  Keeping weeds down may also help prevent the disease.

Curly Top & Skeletonizers

Each week the Master Gardeners handle phone calls on a number of problems.  Two that have come up recently are on Grape Leaf Skeletonizer and Curly Top Virus.  Curly Top Virus is carried by the beet leaf hopper which transmit the disease when it feeds on the plant.  It is a recurring problem in Yavapai County gardens.  There are a couple of remedies that may be helpful.  Check out the articles on Curly Top at  http://cals.arizona.edu/yavapai/anr/hort/byg/archive/curlytopvirus2008.html

http://ag.arizona.edu/gardening/news/articles/14.3.html

The grape leaf skeletonizer strips the green of the leaves between the veins.  Without the green the plant can't survive.  The skeletonizer is a colorful black, yellow and blue striped catepillar that turns into a small black moth.  The caterpillars feed side by side and can quickly strip a leaf to a "skeleton."  You can hand strip the caterpillars from the leafs but be careful.  Wear gloves and a dust mask as they have sting hairs on them that can become airborne.  Spraying Bacillus thuringiensis is also an effective way to control them.