Formation of a Mealybug Biocontrol Research Focus Group for Crush District 11
- Summary: “Formation of a Mealybug Biocontrol Research Focus Group for Crush District 11”
by PI Dr. Stephanie Bolton, Lodi Winegrape Commission
The project has successfully met its objectives as stated during the period of March 2017 –
April 2018. The Lodi Mealybug Biocontrol Research Focus Group met monthly at a local diner
to discuss vine mealybug biocontrol, researching topics such as which beneficial insects are
present and effective in our area, current grower perceptions of beneficial insects and mealybugs,
the likelihood of neighbor cooperation in vine mealybug management, ant control, Movento,
organic options for mealybugs, and other topics related to vine mealybug biocontrol and
management. The Focus Group became a center of learning and exploration where scientists,
extension personnel, growers, pest control advisors, and the industry opened communication
around the subject of mealybug biocontrol in efforts to develop real-world, applicable outreach
materials and events which would propel our local winegrape industry forward and decrease our
risk for further leafroll virus infections.
Through the conversations and learning experienced during the Focus Group monthly meetings,
along with information gathered via expert consultants and educational field trips, a strategy for
mealybug biocontrol in Crush District 11 was established. This simple strategy is:
- Don’t kill the good insects.
- Control the ants.
- Use pheromone mating disruption.
In Lodi, we are still generally in phase 1 where we are teaching growers how to keep their
beneficial insects alive through distribution of an easy-to-read chart based upon UC IPM
guidelines and local experience (available at lodigrowers.com). In August 2017 at a Mealybug ID
Field Day, about 120 growers had a fun time learning how to identify mealybugs which have been parasitized by the Anagyrus wasp, one of the two main biocontrol agents in our region. During the April 2018 Mealybug & Virus Outreach Meeting, about 150 growers learned the significant
role of ants in the vine mealybug and leafroll virus story. The Focus Group has planned ant bait
experiments for 2018 after finding that there is no economical, efficient ant control method
available for large acres of vineyards. While pheromone mating disruption is being used with
success in our region to decrease mealybug populations and to attract beneficial insects, it is still
cost-prohibitive for many growers. Growers were given mealybug traps donated by Suterra at the
April 2018 meeting, which they will bring back in May 2018 for a follow-up Mealybug Trap
Workshop. Thus, they are learning whether the male mealybug is present in their field and how
to use the traps, which is the first step towards neighborhood coordinated pheromone mating
disruption.
By taking the time to fully assess the current mealybug biocontrol management options in the
region and to learn more about the pathogen itself, future priorities for more targeted research on
a larger scale were best determined. Priorities include but are not limited to: discovering an
efficient and cost-effective ant control method for large acreage in Crush District 11, learning how to release Cryptolaemus beetles in our vineyards, and learning how to eliminate underground vine mealybugs following a leafroll virus infected vineyard rip-out.
