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Vegetable IPM Updates Archive
Cooperative Extension
Management Guidelines for Whiteflies and CYSDV on Fall Melons (July 8, 2015)
As growers begin to prepare local fields for fall melons, they should be considering the threat of cucurbit yellow stunting disorder virus (CYSDV). The virus was first identified in desert melons in the fall of 2006 where widespread infection on cantaloupes, honeydews and other melons cost growers a significant portion of their crops. Without question, yields and quality in desert melon crops have been seriously affected by CYSDV infection. Additionally, melon pest management has been affected by CYSDV as insecticide usage on fall melons has increased significantly since 2006. Over the past eight years we have been studying the epidemiology of CYSDV and trying to develop approaches for reducing its impact on fall melon production. In addition, we continue to develop new information on control of the vector of CYSDV (Bemisia whitefly adults). Whitefly numbers this spring and summer have been very moderate to heavy and the incidence of CYSDV on spring melons was high on some late planted spring melons. How this translates into virus incidence on fall melons is not certain, but our experience suggests that you should anticipate risks from CYSDV to be as high as previous years. Further, given the aggressive management programs that PCAs and growers are now using, it will be interesting to see how CYSDV impacts melon production this fall. Our research to date suggests that fall melons produced near cotton or near areas where spring melons were recently produced are at the highest risk of infection. When possible, growers should attempt to isolate fall plantings as far away as possible from these sources of whiteflies and CYSDV. Growers forced to plant fall melons near these crops should be vigilant in minimizing adult whitefly infestation levels with insecticides during pre-bloom growth stages. To view a summary the status of CYSDV in Yuma County and guidelines for management visit 2015 Guidelines for Whitefly and CYSDV Management on Melons.


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For questions or comments on any of the topics please contact Marco Pena at the Yuma Agricultural Center.
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