Old pest, new problem: Bt resistance in European corn borer in North America

The European corn borer (ECB), Ostrinia nubilalis (Lepidoptera: Crambidae), one of the most significant crop pests in North America, was the original target of transgenic corn modified to produce insecticidal toxins from Bacillus thurinigiensis bacteria (Bt corn). For more than 25 years, this has been one of the most successful pest management strategies in history with no indication of ECB resistance to Bt toxins. However, the first case of field-evolved resistance in ECB to a Bt toxin was detected in Nova Scotia, Canada in 2018. With subsequent monitoring, additional resistant populations have been detected in Quebec and Manitoba, Canada in 2019 and 2020, respectively. In 2023, the first Bt resistant ECB were detected in Connecticut, USA. Therefore, a new and significant threat to ECB management is on the horizon in North America and there is rising demand to understand many aspects related to this development.

The objective of this symposium is to raise awareness of Bt resistance in ECB, facilitate the dissemination of recent research findings, and identify critical research gaps pertinent to this issue. The symposium will delve into topics including the current distribution of Bt-resistant ECB, ongoing monitoring and mitigation strategies, and the molecular basis and characterization of resistance mechanisms. Stakeholders from public research and extension, industry, and regulatory bodies will offer insights into their experience and recommendations in managing, monitoring, and mitigating Bt resistance concerning ECB. This symposium will attract a broad audience as this suite of topics will address basic and applied research as well as the impacts that Bt resistance in ECB will have on growers, industry, and government.

A diverse group of expert speakers, of which the majority have committed to speak, will provide coverage of many aspects related to Bt resistance in ECB. A 30 min discussion period will be held at the end of the symposium to allow discussion of related topics such as:

· Characterization of Bt resistance in ECB

· The impact of agricultural landscapes on the distribution of Bt-resistant ECB

· Monitoring of ECB using traditional and genetic based methods

· Management of Bt resistant ECB

· Regulatory and industry response to Bt resistance in ECB

· Research Needs and Potential Collaborations