Testing Avaunt eVo part 1: Carrier volume and adjuvants

After two seasons of working with Avaunt eVo, we have a better understanding of its efficacy and utility against Lygus bug in strawberries. Avaunt eVo’s active ingredient is indoxacarb, which was first registered in 2004 as an ant bait, but now finally was registered for use in strawberries in 2025. Avaunt eVo works by being ingested, which makes coverage a key component of its effectiveness. However, since Lygus hesperus have been exposed to indoxacarb in the vegetable crops in the region for at least fifteen years, the chance of tolerance being present in the field is already very high. My fear was that as Avaunt eVo was sprayed over the three districts, its efficacy was going to be a hit or miss. Even the label says “suppression”. That fear was confirmed by PCAs and my continued work on the product.

We have now done eight separate experiments with Avaunt eVo in 2024 and 2025. In this post I will discuss our laboratory and field work on carrier volume and adjuvants. In short, the data we have suggests that decreasing carrier volume does not improve efficacy.

In early 2025, Colin Koubek, graduate student and research associate, found in the laboratory that Avaunt eVo was best sprayed at 50 gallons per acre. The concentrations at 150 GPA were too dilute to kill L. hesperus in the lab.

It took two to three days before any level of appreciable more mortality could be observed in either the 1st or 2nd instar nymphs. The mortality at 150 GPA was lower than the non-treated mortality in the 1st instar assay (Fig 1). Mortality never exceeded 50% in the 2nd instar assay (Fig 2). The fact that waiting in the non-treated produced greater mortality than the insecticide was surprising.

**Figure 1**. Laboratory testing of indoxacarb at 50 and 150 gal per acre equivalent against 1st instar *Lygus hesperus* nymphs over 7 days. Letters that are the same are not significantly different using Tukey HSD test P > 0.05

**Figure 2.** Laboratory testing of indoxacarb at 50 and 150 gallons per acre equivalent against 2nd instar *Lygus hesperus* nymphs over 8 days. Letters that are the same are not significantly different using Tukey HSD test P > 0.05

In the field, we could not differentiate between the low and higher carrier volume in 2 trials completed in July. The first trial we did a non-replicated examination of 50 GPA vs 150 GPA through a growers rig and found no differences (data not shown).

In a replicated trial, when mixing with two different adjuvants, Broadspred and Dyne-amic, we saw no significant differences between the 50 and 100 GPA treatments (Fig 3).

**Figure 3.** July 2025 trial comparing 50 and 100 gallons per acre carrier volume of indoxacarb in combination with either Broadspred and Dyne-amic adjuvant. Letters that are the same are not significantly different using Tukey HSD test P > 0.05

Conclusion

When Avaunt eVo was registered in strawberries, the label said “suppression” only. My only data in 2024 suggested that using the product was definitely better than doing nothing or even using Brigade. However, in 2025 I was not successful in replicating those results. In Part 2, I will go over my results on efficacy and tank mixing. I will also highlight the caveats to all our studies.

Acknowledgements

I want to personally thank Scott Pierce and Randy Widerberg for giving us space to do this work and their willingness to provide their decades of expertise and knowledge. A more detailed run down of this research will be presented to growers and PCAs this winter. If you have questions about the data, wish to express your own experience with this product, or have a field where the product did not work, please feel free to call me at 805-540-1489 or email at maghaee@calpoly.edu. We are conducting research on resistance monitoring and indoxacarb is one of the chemicals we’re testing to get a better understanding of its efficacy in the field.