Every year mealybugs threaten flourishing vineyards around the country.
Grape, longtailed, vine, obscure—any one of these mealybug species can put the value of your grapes at risk. Mealybugs excrete honeydew, a sweet sticky substance that drops on leaves and fruit. Honeydew not only attracts ants, but also serves as a growth medium for damaging, un-sightly sooty mold. There is a bright side, however. Once mealybugs are detected, there are sev-eral good control options.
Mealybugs create a foul, unattractive mess that can render your grapes unsalable.
Adult female mealybugs are oval with soft, flat, segmented bodies. Although pinkish in color, they are covered in a white, waxy coating that forms spines along the body margin and posterior end. Mealybugs are found in wood crevices or on berries and leaves. They prefer vigorous vines with thick canopies. Ants acerbate the problem, protecting mealybugs from predators and feeding on honeydew.
Eggs are yellowish or orange and are laid in cottony egg sacs. The nymphs are pale yellow and go through four to five instars, depending on the sex, with each instar larger than the one preced-ing it. Adult males have one pair of wings, no mouthparts and die soon after emergence. Mature females are wingless and about 4.8 mm long. During the summer, all life stages may be present at the same time on leaves, vines and grapes.
Symptoms and Impact
Actual feeding damage from mealybugs is minimal. But they create a foul, unattractive mess that can render your grapes unsalable. They leave behind cottony egg sacs, dead mealybugs, mealy looking wax, drops of honeydew on leaves and fruit, ants and sooty mold. On top of that, mealy-bugs are vectors for the grapevine leafroll virus.
In addition to leaving behind cottony egg sacs, dead mealybugs, mealy looking wax, drops of honeydew on leaves and fruit, ants and sooty mold, mealybugs are vectors for the grapevine leafroll virus.
Control and Management Options
Mealybug problems can be managed in a number of ways. Options include biological, cultural and/or chemical control.
Biologicals include parasitic wasps, predaceous midge larvae, lacewings, several species of lady beetles and many other generalist predators. Mealybugs are also susceptible to several diseases, including Entomopthora fungus.
Movento insecticide offers broad-spectrum control of mealybugs by finding and killing these hidden grape pests in dense crop canopies and on plant roots.
Cultural control of these grape pests includes pruning canes to avoid excessive foliar vigor and controlling ant populations.
Movento® from Bayer has proven itself to be highly effective against all stages of the mealybug life cycle, making it an important addition to pest management programs in grapes. Its two-way systemic action distributes broad-spectrum control of sucking pests upward and downward, holistically protecting your crops.
For more information on how you can protect your vineyards from mealybugs and other TNV pests such as aphids, whiteflies, scales, nematodes and psylla, contact your local Bayer representative.