UC IPM Advisor David Haviland recently shared some tips on mealybug control. The goal is to lower mealybug populations, prevent movement, protect the cluster and keep the vines compatible for biocontrol (especially postharvest). Some insecticides effective against vine mealybug include: Chlorpyrifos (delayed-dormant treatment), Buprofezin (best against crawlers), Spirotetramat (foliar applied/systemic in the phloem and xylem), and Neonicotinoids (some soil, some foliar applied).
Moving into 2018, Haviland recommended growers and PCAs consider how temperature and weather impacts pest populations. “Insect development is often driven by temperature,” he said. “When the temperatures are higher, the mealybugs are more active and develop more quickly. In some springs, temperatures gradually warm up over time, and mealybug development is fairly synchronized. This allows growers to use products or growth regulators geared toward controlling the crawler stage in the spring, and they are very effective when the insects are synchronized in their development stage.”
“But in other years, early season temperatures vary from warming up to cold again with inconsistent weather patterns, and this confuses the pest as they start to develop. This puts them out of synchronization as far as development, leading to all stages of the pest present at the same time in the vineyard. In such a case using a pesticide that goes after one stage of the pest will be much less effective.”
As we never know what the weather will bring, growers and PCAs need to pay close attention to weather patterns and spring mealybug populations to determine the most effective IPM approach to take for successful mealybug management.
Haviland will be presenting his latest research on vine mealybug management through mating disruption technology with sprayable pheromone at the annual Grape, Nut & Tree Fruit Expo coming up on November 14th at the Big Fresno Fairgrounds. The expo will run from 7 a.m. to 2 p.m., and Haviland’s presentation will begin at 10:30 a.m. Growers and PCAs are invited to attend with free admission. Don’t miss Haviland’s presentation, the many other informative grower seminars that will take place. Pre-register for the expo here.
-By Matthew Malcolm, American Vineyard Magazine