A landmark 12-year study, published in Science (Ye et al., 2025), reveals shocking economic losses for farmers relying on rootworm-resistant GMO corn. This in-depth analysis, spanning ten key U.S. Corn Belt States, delivers original data quantifying regional yield disparities — with western States suffering 1,207 kilos per acre losses — and confirms accelerated pest resistance.
Beyond the raw data, this article provides unique insights, including the ‘finite resource’ analogy, and connects these findings to the dominance of the ‘Big 4’ seed corporations, drawing from Dongo’s GMOs, the Big Scam (2015). Explore the critical impact of GMO technology on sustainable agriculture, and the challenges it poses to agroecology-driven and equitable farming practices.
Study methodology: a 12-year retrospective analysis
The study, conducted by a team of 20 researchers from 12 universities in the U.S., China, and Canada, analyzed data spanning 12 years (2004–2016) across 10 U.S. Corn Belt States. The research focused on the adoption and impact of Bt corn hybrids, genetically engineered to produce toxins lethal to corn rootworms.
The team collected data on pest pressure, crop yields, and farming practices, comparing regions with continuous corn planting (western Corn Belt states: Illinois, Iowa, Minnesota, Nebraska, North Dakota, South Dakota, and Wisconsin) to those practicing crop rotation (eastern states: Indiana, Michigan, and Ohio).
Crop rotation reduces the need for transgenic corn or insecticides, yet the study found that Bt corn adoption remained widespread across both regions. Researchers also evaluated the economic costs of Bt corn adoption, including technology fees and the erosion of pest susceptibility due to resistance development.
Major outcomes: economic losses and pest resistance
The study revealed several critical outcomes:
• regional disparities in pest pressure. Rootworm pressure was significantly higher in western states, where continuous corn planting is common, compared to eastern states that practice crop rotation;
• yield losses. From 2014 to 2016, yield losses attributed to rootworm damage averaged 1,207 kg per acre in western states, compared to just 216 kg per acre in eastern states;
• overuse of Bt corn. Despite lower pest pressure in eastern states, farmers across the region continued to use Bt corn hybrids at similar rates, leading to unnecessary economic losses and accelerated pest resistance;
• resistance development. The study confirmed that rootworm resistance to Bt toxins has increased since 2009, undermining the long-term effectiveness of the technology.
Economic and ecological costs of overuse
The researchers identified two major costs associated with the overuse of Bt corn:
- technology fees. Farmers pay a premium for Bt hybrid seeds, which often bundle multiple traits, regardless of whether they are needed. This practice, driven by the ‘Big 4’ (Bayer-Monsanto, Corteva, Syngenta, and BASF), locks farmers into a cycle of dependency;
- erosion of pest susceptibility: overuse of Bt traits accelerates the development of resistance, reducing the technology’s effectiveness over time.
Christian Krupke, the study’s lead entomologist, likened Bt corn to a ‘finite resource’ that diminishes with each use. ‘Every time you use it, you erode a little bit of susceptibility’, he explained. ‘So it’s a little less likely that it will work as well next time’.
The Big 4: winners of the ‘GMO affair’
The Big 4 have reaped enormous profits from the global GMOs market, while farmers struggle with rising input costs and declining soil fertility. The bundling of seed traits forces farmers to pay for unnecessary technologies, further enriching corporations at the expense of agricultural sustainability. As highlighted in GMOs, the Big Scam (Dongo, 2015), this system prioritizes corporate profits over farmer welfare and ecological health.
Moreover, the overuse of chemical pesticides, often paired with GMO crops, has exacerbated ecological damage. A 2019 study by Di Bartolomeis et al., found that the acute insecticide toxicity loading (AITL) of pesticides used on U.S. agricultural land has increased significantly, posing risks to pollinators, aquatic life, and human health. This underscores the need for a shift away from chemical-intensive agriculture.
The risk of pesticide pollution at the global scale
The study by Tang et al. (2021) assesses the global risk of pesticide pollution by modeling the environmental impact of 92 active pesticide ingredients across major agricultural regions. The research evaluates pollution risks in soil, surface water, and groundwater, identifying areas where pesticide use may exceed ecological safety thresholds.
The findings reveal that about 64% of global agricultural land is at risk of pesticide pollution, with hotspots in high-intensity farming regions such as China, India, and parts of Europe and the United States. The study highlights the urgent need for sustainable pesticide management to mitigate environmental and ecological risks.
A call for sustainable pest management
Ye et al. (2025) advocate for a more targeted approach to pest management, emphasizing the need to balance economic and environmental sustainability. Key recommendations include:
• crop rotation. Reducing pest pressure by alternating corn with other crops;
• farmer education. Raising awareness about the financial and ecological costs of overusing Bt corn;
• selective use of Bt traits. Tailoring the use of Bt hybrids GMOs to regions with high pest pressure;
Christina DiFonzo, a field crops entomologist at Michigan State University, compared the current seed trait bundling to outdated cable TV packages, where consumers paid for hundreds of channels they didn’t want. She suggested that farmers would benefit from a ‘pick list’ of seed traits tailored to their specific needs, which would also help manage insect resistance.
Lessons for future technologies
The study by Ye et al. (2025) serves as a critical case study in the development and deployment of transgenic technologies. Ziwei Ye, the study’s lead author and an assistant professor at Renmin University of China, highlights the importance of preserving Bacillus thuringiensis (Bt) technology for future generations. ‘Bt technology has provided net benefits, helping to safeguard beneficial organisms and maintain soil ecosystem health’, she explains.
However, the first author warns that overuse risks rendering the technology ineffective—an issue comparable to antibiotic overuse leading to bacterial resistance.
David Hennessy, a co-author and professor at Iowa State University, emphasizes that individual farmers may not fully consider the broader implications of their choices on pest resistance. ‘Overusing Bt may make sense at the individual level, but in the long run, widespread reliance will accelerate resistance development and shorten the effective lifespan of the technology’, he states.
Commentary on the study
The writer (Dongo) presents a broader critique, arguing that Bt hybrid genetically modified organisms (GMOs), much like herbicide-resistant (HR) GMOs, are ultimately unsustainable for both farmers and the environment. This perspective aligns with concerns raised in previous research, which has documented increasing instances of resistance development in target pests (Tabashnik & Carrière, 2017; Carrière et al., 2021). Studies show that corn rootworm (Diabrotica spp.) and other major pests have evolved resistance to Bt toxins, reducing their efficacy and necessitating increased pesticide use (Gassmann et al., 2014; Zhao et al., 2020). This resistance not only threatens crop yields but also undermines integrated pest management (IPM) and regenerative agriculture strategies, which depend on diverse control methods to maintain pest susceptibility.
Beyond resistance issues, the environmental risks associated with Bt crops are also a growing concern. Research indicates that Bt toxins can persist in soil ecosystems, potentially affecting non-target organisms such as soil microbiota and beneficial insects (Hilbeck & Otto, 2015; Székács & Darvas, 2018). Additionally, the widespread adoption of monoculture farming with Bt hybrids has been linked to declining agroecosystem diversity, exacerbating vulnerabilities to pest outbreaks and reducing overall ecosystem resilience (Andow & Zwahlen, 2006).
Sustainable farming under threat: GMO overuse & corporate control exposed
The Ye et al. (2025) study provides a crucial, data-driven narrative of the economic and ecological risks stemming from indiscriminate GMO corn use. This research stands out for its long-term analysis and its ability to quantify yield losses and pest resistance, offering original insights into the ‘finite resource’ dilemma. This article extends beyond the study, providing a critical lens on corporate influence and advocating for sustainable pest management through crop rotation and targeted Bt trait use.
As highlighted in Dongo’s (2015) analysis and reinforced by global studies on pesticide pollution, true agricultural sustainability demands addressing the systemic issues of corporate control and farmer dependency. Only integrated pest management (IPM) and regenerative agriculture strategies, to be driven towards the agroecology model, can safeguard future technologies and promote a balanced, ecologically sound agricultural system, for the benefit of all stakeholders ‘from seeds to fork’.
#Égalité, #PeaceLandDignity
Dario Dongo
References
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Dario Dongo, lawyer and journalist, PhD in international food law, founder of WIISE (FARE - GIFT - Food Times) and Égalité.
