Insect Growth Regulator Now Registered for Fig Scale Control

Author – Robin Siktberg

While the US isn’t a major producer of figs, ranking eighth in world production, it does produce an average of 47 tons per year. Most figs in the US are grown in Central California, where the climate matches the arid, Mediterranean-like conditions figs need to thrive. Since figs are not a major crop, they are usually not a labeled use on crop protection products, which limits the products available to fig growers. This is where the IR-4 Project comes in.

Recently, IR-4 researchers conducted residue tests on figs for buprofezin, which is marketed as Applaud 70 DF Insect Growth Regulator and manufactured by Nichino America.  Buprofezin provides excellent control of scale insects, which are a particular problem on fig trees, especially the fig scale, Lepidophases conchiformis. This pest has three to four generations during the growing season; the scales first infecting leaves and twigs and moving to fruit when it develops. The scales cause scarring of the fruit surface, and of course, reduced yield, by weakening the plant if uncontrolled. There are very few other products registered for scale control on figs, so the registration of buprofezin will be of particular benefit to growers.

Fig scale damages fruit by causing scarring on the outer surface. Photo: United States National Collection of Scale Insects Photographs , USDA Agricultural Research Service, Bugwood.org

Ability to Specifically Target Pests

Buprofezin is specific to hemipteran insects, a group that includes many horticultural pests with piercing, sucking mouthparts, such as scales, mealybugs, leafhoppers, planthoppers and the nymphal stages of whitefly. It works by suppressing egg laying, reducing the viability of the eggs that are laid, and by inhibiting the production of chitin, which is important in the formation of insects’ protective exoskeleton. Because it is so specific, buprofezin has very little impact on beneficial insects and mites, so it fits in easily within an integrated pest management (IPM) program. Buprofezin has long residual activity, making it ideal for the prolonged period of scale emergence in the spring in figs.

Buprofezin is already approved  for use on almonds, bananas, citrus, cotton, cucumbers, melons, tomatoes, pumpkins and other squash.

To establish maximum residue levels (MRLs) on figs, researchers applied Applaud 70 DF Insect Growth Regulator to multiple plots in California. Two foliar applications 14 days apart were made on fruiting trees at the rate of 2.0125 lbs./active ingredient per acre applied according to label directions. 14 days after the second application, fruit from each plot was collected and submitted to the Food and Environmental Toxicology Laboratory at the University of Florida, Gainesville, and tested for residue levels.

US EPA approved the expansion of the buprofezin (Applaud 70 DF) label for figs in California in September 2019.

PR# 11342 Fig (Fig Scale)

Robin Siktberg is a custom content editor at Meister Media Worldwide; rasiktberg@meistermedia.com.