Demonstration of Different Application Methods for CheckMate® NOW-F Sprayable Mating Disruption

 Suterra’s mating disruption technology offers the industry the longest-acting sprayable option to protect nut crops from navel orangeworm (NOW) damage while delivering a unique mating disruption mode of action. CheckMate^® NOW-F is labeled for application by ground and air, and many growers are taking advantage of the flexibility of this formulation to successfully use a variety of traditional and novel methods to distribute sprayable pheromones into their orchards.

Our team recently contributed an article to West Coast Nut detailing why sprayable mating disruption may be ideal for your operation this season, beginning on page 54.

Ground, Aerial, Ultra-Low Volume Applications

In collaboration with a commercial almond grower operation in 2022, a program using CheckMate^®  NOW-F sprayable pheromone was implemented using three different application methods. The results demonstrate the versatility and efficacy of different application approaches that can be tailored to individual operational activities throughout the season.

The 76-acre almond block was divided into two plots. CheckMate^®  NOW-F applications and the grower standard insecticide program were applied to the east 40 acres (historically higher NOW pressure). The west 36 acres received only the grower standard insecticide program (serving as the non-mating disruption reference). CheckMate^®  NOW-F was applied at the label rate of 3.0 fl. oz./acre for each application, and standard label rates were used for all insecticides.

CheckMate^®  NOW-F application methods, timings, and tank-mixes:

• The first application was made on April 27 as a tank-mix with chlorantraniliprole, abamectin, bifenthrin, and an adjuvant, applied full-cover by ground at 150 gallons per acre final volume using a conventional air-blast sprayer.
• The second application was made at the grower’s hull split spray timing on July 7 as a tank-mix with chlorantraniliprole and an adjuvant, applied full-cover by air (helicopter) at a final volume of 30 gallons per acre.
• The third application on August 10 was a stand-alone application using an ultra-low volume rig; applied every other row with a final volume of 5 gallons per acre, allowing the grower to rapidly distribute the pheromone across the 40-acre plot (total application time of 2 hours at 5 to 6 mph, including time to refill the tank).

Male moth capture in pheromone trap located in non-mating disruption reference.

Trap Suppression

The expected residual activity of NOW-F is up to 30 days in the field. Following the first application, cumulative trap suppression (total males caught) was 99.5% over a 30-day period. We continued to observe significant trap suppression for 57 days following the late-April application, with 98% fewer males caught in the mating disruption plot. During the last week of June, approximately 9 weeks after application, we observed a small spike in the pheromone traps just before the hull split-timed application.

The second application showed significant trap suppression (cumulative 5 males caught in the NOW-F plot over 29 days following the application), although trap captures overall were down in both plots in the month following the July application. Five weeks after the second application, trap counts started to pick up again across the orchard, and the third NOW-F application was made.

Cumulative trap capture following the third application was reduced by 93% in the NOW-F plot over 35 days, and trap numbers continued to be suppressed in the mating disruption plot throughout the remainder of the trapping period into November. Figure 1 below shows the season-long NOW trap capture in both plots (arrows indicate spray timings).

Figure 1. Season-long navel orangeworm (NOW) trap capture in pheromone traps in an almond block in 2022. Treatments included three applications of CheckMate^®  NOW-F with the Grower Standard insecticide program (NOW-F + GS) versus the non-mating disruption reference (Grower Standard insecticide program only). Black arrows represent the treatment timings.

Overall, cumulative trap suppression for the season following the first application was 86%. Each CheckMate^®  NOW-F application is applied to target a particular 30-day interval, and pheromones are not necessarily expected to be active over the entire season when using targeted sprayable mating disruption applications. This case study showed that populations remained lower where NOW-F was used, even during intervals where pheromone activity was not expected. This underscores the value of keeping mating disruption in the program to significantly suppress every subsequent generation.

Harvest Damage Reduction

This particular orchard is one of the latest harvested, an unavoidable operational factor leading to higher NOW pressure in the block. Harvest damage assessments were evaluated from field-collected almonds on August 30 (Nonpareils, 1350 nuts evaluated from 54 sample sites in the plot) and October 5 (pollinizers Monterey and Fritz, 1350 nuts evaluated from 54 sample sites in the plot). Navel orangeworm damage in the NOW-F plot was reduced by 53% in the Nonpareils and 49% in the pollinizers compared to the non-mating disruption reference plot. This case study reinforces the many other experiences of growers who have successfully used NOW-F in their customized programs.

This case study is an example meant to show the versatility and efficacy of different application methods. It is not meant to recommend a specific spray program (number of sprays, spray timings). Like any sprayable pest management input, the number of CheckMate^®  NOW-F applications, spray timings, and application methods should be decided in consultation between growers and their crop advisers.

For more information on using sprayable pheromones in your IPM program, please contact Suterra’s experts at https://www.suterra.com/contact-us.