Neonicotinoid Seed Treatments: Limitations and Compatibility with Integrated Pest Management

Abstract

Core Ideas Recent educational offerings incompletely addressed neonicotinoid seed coatings. These insecticidal coatings are common on corn, soybean, and other crop seeds. Current use patterns violate core principles of integrated pest management. We present an overview of these products, focusing on some key limitations. Deploying neonicotinoids more judiciously will reduce their negative side effects. Educational materials guiding the use of pesticides are often sponsored or co‐created by pesticide manufacturers, raising potential conflicts of interest. For example, early in 2017, two registrant‐sponsored webinars from the American Society of Agronomy addressed benefits of neonicotinoid seed coatings, which are routinely applied to seeds of many field crops. While these products can protect yield in certain situations, they also carry significant limitations; unfortunately, these presentations avoided such downsides. Here, we provide an overview of key limitations of neonicotinoid seed treatments (NST). First, we address Integrated Pest Management (IPM) and how current use of NST violates its key principles and ignores lessons learned. Second, we address inconsistent yield responses, resistance concerns, and nontarget effects. Third, we return to IPM to discuss how this proven framework can be used to more effectively guide and steward NST to avoid mounting reports of negative side effects.

Effects of clothianidin‐treated seed on the arthropod community in a mid‐Atlantic no‐till corn agroecosystem

“…Additionally, the majority of corn acreage in the US is now planted with seed treatments of clothianidin and other neonicotinoid insecticides at rates higher than the 0.25 mg a.i. per kernel rate evaluated in this study, thus, our study likely underestimates effects even within a single season.…”

“…However, insecticide seed treatments are often used in fields that do not face regular pest pressure, as insurance against occasional pests. Insecticide use in corn has increased from <50% of corn in the US being treated with insecticides from the 1950s to the 1990s, to 79–100% of corn being treated with neonicotinoid seed treatments by 2011, without a corresponding increase in pest pressure . Even when targeting specific key pests, IPM practices can have greater economic benefits than preventive seed treatments.…”

“…`A study comparing prophylactic insecticide use (seed treatments and foliar sprays) to IPM practices (weekly scouting and targeted foliar sprays) for soybean aphid control found that while all three treatments were effective in preventing damage, the IPM treatment was the most cost‐effective . Unfortunately, due to the lack of availability of untreated corn seed, growers often have no choice but to use neonicotinoid seed treatments . Corn seed lacking insecticide treatment needs to be made widely available to growers, so that insecticide seed treatments can be used only when economically warranted.…”

“…Because insecticide seed treatments are prophylactic, they are often considered to be incompatible with IPM. 7,90 Such preventative practices are appropriate in situations with a high likelihood of pest pressure, such as when planting into turf, or into a field that has multiyear pests like wireworms (Elateridae) that cannot be controlled using foliar insecticides, 96 or in fields where chronic early season pest pressure has been observed. However, insecticide seed treatments are often used in fields that do not face regular pest pressure, as insurance against occasional pests.…”

“…Insecticide use in corn has increased from <50% of corn in the US being treated with insecticides from the 1950s to the 1990s, to 79-100% of corn being treated with neonicotinoid seed treatments by 2011, without a corresponding increase in pest pressure. 90 Even when targeting specific key pests, IPM practices can have greater economic benefits than preventive seed treatments. 'A study comparing prophylactic insecticide use (seed treatments and foliar sprays) to IPM practices (weekly scouting and targeted foliar sprays) for soybean aphid control found that while all three treatments were effective in preventing damage, the IPM treatment was the most cost-effective.…”