Ag Alert. June 8, 2022

Sponsored by:

www.brandt.co

they hide underneath old bark, making it hard to penetrate with sprays. A foliar insecticide has been the staple product for controlling mealybugs. It is absorbed by the leaves and moves systematically into the phloem and xylem of the plant. A newer kind of approach has been mating disruption.The pheromone disrupts the males so they can’t find the females and mate. Dispensers in the vineyard slowly release the pheromone. Mating disruption impacts the populations, es- pecially in the fall, by preventing breeding and overwintering, which also decreases populations the following year. There is a pheromone that can be sprayed on, too. The use of predatory wasps is another ap- proach, which has the potential to help combat pests that hide underneath the bark. Systemic insecticides and pheromones are becoming the go-to controls for combating mealybug populations and disrupting mat- ing cycles.

Mealybugs are problematic in winegrapes. The main pest is the vine mealybug, but there is also the grape mealybug. The difference be- tween the two is the vine mealybug has more generations, as many as seven to eight per year. By comparison, the grape mealybug has two to three generations annually. Mealybugs put pressure on the vine by suck- ing the vascular carbohydrates out. They then move into the bunches and create a sticky, sooty mold. Once the pests infect the vines, they damage the grapes, which can result in yield loss. The mealybug can also cause sec- ondary disease movement, so reducing its populations also reduces pressure from sec- ondary diseases. Ants are also problematic. They feed off of the sugary secretion produced by the mealy- bug and, while they don’t damage the grapes, they shield them from predatory insects such as wasps or lacewings. Treatment for mealybugs is difficult because

PEST CONTROL ADVISOR

What works for mealybug pests in winegrapes?

Cameron Jones Nutrient Ag Solutions, Stockton

MEMBER

BRANDT ® Smart B-Mo High Performance Foliar Nutrition

Revolutionary New Form of Boron and Molybdenum

■ Formulated for maximum nutrient mobility and efficiency ■ Compatible with insecticides, herbicides, fungicides and other micronutrients, including calcium ■ Highly soluble and stable across a broad pH range ■ Up to 8x more efficient than 10% boron

For more information, visit brandt.co or email info@brandt.co

Brandt Consolidated, Inc. www.brandt.co

June 8, 2022 Ag Alert 17

Powered by