By: Gerald Dlubala
Winemakers face multiple challenges daily. One of the biggest and most important challenges is managing and keeping pest damage within their vineyards to a minimum. Battling pest infestations can be daunting because just as pests can be in the soil, they also can feed on every part of your vines, from the root up through the vine, leaves and fruit clusters.
Additionally, many are undetectable during visual inspections, making it essential for vineyard managers to implement an integrated pest management (IPM) system to maintain higher yields with better quality fruits in a more vibrant and vigorous growing climate.
Some of the more common vineyard pests include phylloxera (a microscopic aphid that feeds on the roots of grapevines), roundworms (nematodes), grapevine moths and leafhoppers.
However, the most damaging pests may be mealybugs – in this case, vine mealybugs.
The Vine Mealybug Invades Grapevines from Root to Cluster
The vine mealybug develops through seven stages: the egg, the first, second and third instar nymph stages, the prepupa, pupa and finally into an adult. Eggs are golden-yellow and contained in a cotton-like egg sac (ovisac), each sac containing 300 to 500 eggs.
Nymphs are smaller than, but comparable to, an adult female. The prepupa and pupa stages are only evident in the male. After a complete metamorphosis, the winged male emerges from the pupa, dark orange with long tail filaments and transparent wings. Males have no mouthparts. Females are larger, up to 3 millimeters more voluminous, and elongated-oval with no wings. The female vine mealybug is covered with a fine waxy material, with 18 wax rods around the edge of its body, two slightly longer filaments at its tail section and a dark, longitudinal stripe running over the body.
The vine mealybug’s life stages occur while it inhabits the vine year-round, depending on the grape growing region. Nymphs are located under the bark, at a graft union, on a trunk pruning wound or below the base of spurs. Some areas also have vine mealybug eggs, crawlers, nymphs, and adults within developing buds and on roots.
As temperatures moderate and start to warm, vine mealybug populations can increase and become more easily apparent with visual inspection. The pests move to the cordons and canopy. By late spring and into summer, the vine mealybugs are under the bark and on all parts of the vine, including the trunk, cordons, canes, leaves, clusters, and roots. Mealybugs can be transferred from vineyard to vineyard or from plant to plant through unsanitized garden tools and equipment, clothing and even by hitching a ride on ants to other parts of the plant.
Kent Daane knows about vine mealybugs. Daane is a cooperative extension specialist at the University of California Berkeley. He studies different mealybug populations worldwide and focuses on large-scale management tactics. Daane sees opportunities to reduce vine mealybug populations in the same way that previous pest control eradication programs helped with the European grapevine moth, a combination of neighborhood-driven monitoring, trapping, spraying, and mating disruption programs.
In a recent podcast for www.vineyardteam.org, Daane explains how the vine mealybug spreads and how grape growers can band together and manage the pest. His focus was on the regions where grape growers hold the grapes on the vine for extended periods to build up brix levels. That’s when and where he sees the greatest damage occurring.
Daane said that growers are constantly adapting, improving, and changing. Spraying is an expenditure in time and money, and growers are always looking to reduce insecticides while being more efficient with fewer materials. That desired efficiency may come with more timely spraying, the use of natural enemies and mating disruption.
Daane added that it can come down to costs, which usually indicates a tradeoff. If a grape grower wants to use mating disruption, they may be able to reduce the use of insecticides. The organic vineyard may require more frequent applications, sometimes every 10 to 14 days, because of the shorter residual time. If they intend to spray while also releasing beneficial insects, that timing becomes even more critical. Enhancing natural enemies will enhance generalist predators, so cover crops, pollen and nectar come into the conversation. Additionally, using natural enemies like ladybird beetles, green lacewings and minute pirate bugs means remaining patient enough to let them work and increase their population.
For those that are spraying, Daane says that the number one thing you can do to enhance and keep beneficial insect populations is to spray your vineyard in sections and at different times so you’re not spraying the whole vineyard at one time, providing a refuge for beneficial insects. Growers using beneficial insects must find a balance between chemical and biological to preserve those good predators. By leaving some of the area unsprayed, you’re leaving a refuge in which the beneficial insects can move to and survive. Most natural enemies of the mealybug are winged as adults, while the female mealybug is slow-moving and never winged.
Additionally, Daane said that because there are several different mealybug species, it’s important to know which species is in your vineyard so that you can apply the proper pest management program. A local extension office can help identify collected samples if there are any questions.
Suterra LLC, the Global Leader in Environmentally Sustainable Pest Control
Suterra’s products treat millions of acres of tree fruit, nut, citrus, vine, and vegetable crops annually across five continents. Their products use naturally occurring compounds like pheromones, resulting in non-toxic modes of action with no harmful residues left on food. Additionally, their products do not leach into soil or groundwater like conventional or more traditional pesticides. Suterra’s Integrated Pest Management systems provide solutions for vineyard pests, including the vine mealybug, by using pheromones to disrupt their mating pattern, effectively decreasing populations.
Emily Symmes, PhD, and senior manager in technical field services at Suterra, tells The Grapevine Magazine that preventative control of vine mealybug is more critical than ever in today’s wine industry.
“With rising production costs, labor shortages and increased regulatory pressures on chemical use, proactive vine mealybug management is essential to prevent costly infestations,” said Symmes. “Cutting back on pest management to save costs may seem tempting, but neglecting vine mealybug control can lead to severe infestations, reduced yields, lower fruit quality, a greater need for expensive corrective treatments and ultimately, greater financial losses. Prevention helps maintain vineyard health, fruit quality and overall profitability in an already strained industry.”
Symmes added, “Unchecked mealybug populations and leafroll viruses can spread rapidly across vineyards, requiring more costly interventions and premature vineyard replanting, a major capital expense. Vine mealybugs produce honeydew, which leads to sooty mold that can compromise grape quality and lower the value of fruit at harvest. Moreover, they are primary vectors of Grapevine Leafroll-associated Viruses (GLRaVs), which reduce vine vigor and lifespan.”
In a competitive market, maintaining premium fruit quality is critical for securing contracts and achieving profitable pricing and long-term vineyard sustainability. Investing in consistent, proactive control helps avoid this compounding cost and preserves vineyard assets for future profitability.
Incorporating a Strategic Approach to Optimize Pest Management
Vineyard owners and managers have options when it comes to pest solutions. They can choose the method or methods that are optimal for their specific vineyard, considering the types of grapes grown, the size of the vineyard and the extent of their pest problems. A proper and effective pest management solution should feature a combination of pest management solutions.
“Growers can optimize their pest management programs by focusing on early interventions, (monitoring and treating infestations before they escalate), using mating disruption to proactively reduce populations and minimize insecticide use, encouraging biological control organisms for effective natural pest suppression and employing targeted applications with chemical rotations to mitigate insecticide resistance,” said Symmes.
“Mating disruption is a highly effective preventative tool for controlling mealybugs and reducing virus spread. It also enhances the effectiveness of other pest management strategies. Options include Celeda™VMB vapor dispensers for year-round control and CheckMate®VMB-F, a sprayable formulation for precision timed pheromone applications. These solutions provide a cost-effective, sustainable approach to long-term vineyard health.”
Celeda™VMB was developed by Suterra’s team of chemists, engineers and materials scientists for maximum performance and longevity controlling vine mealybug. CheckMate®VMB-F is the world’s first and only sprayable option for vine mealybug control. It easily fits into any growers’ existing integrated pest management program. CheckMate®VMB-F is tank-mixable with common agrochemicals and works well with nearly any water volume.
“A well-managed vineyard remains more resilient in difficult market conditions, producing high-quality fruit that retains value,” said Symmes. “Strong pest control also prevents virus spread, protecting not only individual vineyards but the broader winegrowing region. By maintaining vine health today, growers ensure their businesses remain viable and competitive when the market rebounds.”
For more information about Suterra, to ask a question or to find how they can help you with your Integrated Pest Management (IPM) program, visit Suterra LLC at www.suterra.com
