Photo by: Jack Kelly - UC Statewide IPM Program
A section 18 temporary emergency exemption has been made for the insecticide Sefina®, a BASF product, for the use against Lygus spp. in California strawberries. This emergency exemption is available from May 20 to June 3, 2024 in Monterey, San Luis Obispo, Santa Barbara, Ventura, and several other counties. A single application is permitted at 14 ounces per acre. Growers must register with their local county for the opportunity to use this product, some of the steps that need to be taken prior to its use include:
Having a registered private applicator for the site
Obtaining a permit from the county, similarly to restricted material permitting
Declaration of treated acreage at the time of permit registration
24 hour notice of intent
Wind speed measurement on the upwind side of the field immediately prior to application
Possession of a copy of the section 18 emergency exemption at the time of application
Submission of a final report to the agricultural commissioner's office within 45 days of the expiration date of the exemption detailing the amount of product used, acres treated, estimated effectiveness, and potential adverse effects
It should also be noted that a maximum of 17,000 acres of strawberries may be treated under this exemption, which is about 50% of strawberry acreage in California in standard years
The active ingredient of Sefina® is afidopyropen, which is produced by the fungus Penicillium coprobium, and is classified as a group 9 insecticide according to the Insecticide Resistance Action Committee. Sefina® is a foliar ground applied translaminar product and works generally against piercing sucking insects such as aphids, whiteflies, and Lygus spp. Currently, no cross resistance has been demonstrated between afidopyropen and organosphophates or neonicotinoids, two chemical classes that are currently registered in California strawberries.
A recent study by Horikoshi, R., Hoto, K., and Mitomi, M., et al. demonstrated that afidopyropen appears to have low toxicity to bees and other beneficial organisms. The lethal dose of aifdopyropen that killed 50% of bees in a field setting was at the rate of 47.2 grams of active ingredient per acre, while only 20.4 grams of active ingredient per acre is permitted under this emergency exemption. The dose which killed 50% of lacewing and minute pirate bug species in contact assays exceeded 100mg/L, further demonstrating soft properties on beneficial species. A study by Vivek Kumar, Cindy L. McKenzie, and Lance S. Osborne has shown that there were no significant differences in motile life stages of Amlyseuis swirskii, a species of predatory mite, on plants treated with afidopyropen versus an untreated control in greenhouse conditions. The re-entry interval for Sefina® is 12 hours and predatory mite application should be planned for after this interval has expired.
This emergency exemption will only last until June 3, 2024 so many growers are eager to register to use this product since lygus bugs are such problematic pests in California strawberries. The last emergency exemption that was permitted in strawberries for the use against lygus bugs was in late 2018 and early 2019 for the product Sequoia®. Historically, lygus bug numbers drastically increase in strawberry fields as local vegetation in the foothills begins to dry out. Many pest control advisors and growers would like to see an extension on this exemption since it would feel like a waste to not use this product when lygus bug pressure is at its peak.
Sources and Links:
Horikoshi, R., Goto, K., Mitomi, M. et al. Afidopyropen, a novel insecticide originating from microbial secondary extracts. Sci Rep 12, 2827 (2022). https://doi.org/10.1038/s41598-022-06729-z
Vikek Kumar, Cindy L. McKenmzie, Lance S. Osborne Effect of Foliar Application of Afidopyropen on Bemisia tabaci and Amblyseius swirskii. Arthropod Management Tests 43 (2018). Doi: 10.1093/amt/tsy071
Sefina® Section 18 Emergency Exemption: https://apps.cdpr.ca.gov/section18/assets/registration/labels/2702.pdf?token=1716586850973
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