IPM reduces insecticide applications by 95% while maintaining or enhancing crop yields through wild pollinator conservation

Abstract

Pest management practices in modern industrial agriculture have increasingly relied on insurance-based insecticides such as seed treatments that are poorly correlated with pest density or crop damage. This approach, combined with high invertebrate toxicity for newer products like neonicotinoids, makes it challenging to conserve beneficial insects and the services that they provide. We used a 4-y experiment using commercial-scale fields replicated across multiple sites in the midwestern United States to evaluate the consequences of adopting integrated pest management (IPM) using pest thresholds compared with standard conventional management (CM). To do so, we employed a systems approach that integrated coproduction of a regionally dominant row crop (corn) with a pollinator-dependent specialty crop (watermelon). Pest populations, pollination rates, crop yields, and system profitability were measured. Despite higher pest densities and/or damage in both crops, IPM-managed pests rarely reached economic thresholds, resulting in 95% lower insecticide use (97 versus 4 treatments in CM and IPM, respectively, across all sites, crops, and years). In IPM corn, the absence of a neonicotinoid seed treatment had no impact on yields, whereas IPM watermelon experienced a 129% increase in flower visitation rate by pollinators, resulting in 26% higher yields. The pollinator-enhancement effect under IPM management was mediated entirely by wild bees; foraging by managed honey bees was unaffected by treatments and, overall, did not correlate with crop yield. This proof-of-concept experiment mimicking on-farm practices illustrates that cropping systems in major agricultural commodities can be redesigned via IPM to exploit ecosystem services without compromising, and in some cases increasing, yields.

Carryover insecticide exposure reduces bee reproduction across years

“…Could such an approach be used in other cropping systems? Certainly, each has its own challenges and attributes, but this work ( 7 ) suggests that the types of effects observed by Stuligross and Williams could be reduced with expanded IPM practices in areas where better bee stewardship is needed.…”

“…For example, a recent study showed that using IPM in both a wind-pollinated field crop (maize) and a pollinator-dependent specialty crop (watermelon) resulted in no maize yield losses and improvements in watermelon yield. Further, within just a single year of using IPM, wild bee visitation of watermelon increased ( 7 ). Thus, an IPM approach could result in reduced insecticide use and improved yields and result in a rapid response by pollinators.…”

“…Then, these data can inform policies and regulations that determine how agrochemicals are used. For example, because “the [pesticide] label is the law” ( 8 ), changes in application rate, timing, etc., on pesticide labeling could reduce impacts on pollinators relatively quickly ( 7 ). Further, as new chemistries or formulations come on the market, Stuligross and Williams’ ( 6 ) work underlines the importance of continuing to observe subtle effects and their causes.…”

Impacts of Wildflower Interventions on Beneficial Insects in Fruit Crops: A Review

“…IPM methods aimed at pest control might also benefit pollinating insects—key contributors to fruit growing—and improve yield and quality [ 5 , 6 , 7 ]. Indeed, IPM practices can increase crop yields through the preservation of pollinating insects [ 8 ]. Recently, Egan et al [ 9 ] proposed the introduction of a systematic framework for integrated pest and pollinator management (IPPM).…”

Plant growers’ environmental consciousness may not be enough to mitigate pollinator declines: a questionnaire-based case study in Hungary

“…in the European Union all neonicotinoids except acetamiprid) after they have been proven to harm non-target insects (like bees) in addition to the pest species targetted. In fact, the transition to alternative agricultural practices is possible without yield losses (EPRS 2019) whilst pest damage can be reduced and farm profitability maintained after lowering, but not completely abandoning, pesticide use (Lechenet et al 2017; Pecenka et al 2021). Despite the increasing number of organic farms (European Commission n.d. a; Willer and Lernoud 2018) in the European Union, the process leading to biodiversity-friendly farming can take years because the current conventional plant protection strategies employed on non-organic farms still require synthetic pesticide input.…”