Economic and Environmental Impacts of First Generation Genetically Modified Crops

This research paper analyzes the economic and environmental impacts of first-generation genetically modified (GM) crops, specifically Roundup Ready (RR) soybeans, Bt cotton, and Bt corn, with a focus on the United States and Argentina. The author examines adoption rates, pesticide use, and yield data, concluding that while some environmental benefits exist—such as reduced soil erosion from no-till systems—the technology has led to increased herbicide volumes, 'yield drag' in RR soybeans, and emerging ecological risks including weed resistance and soil microbial shifts.

• In the United States, Roundup Ready (RR) soybeans generally require more herbicide by volume than conventional soybeans, with some estimates indicating a 5% to 10% increase in herbicide-active ingredient per acre.
• RR soybean cultivars in the U.S. consistently exhibit a 'yield drag,' producing 5% to 10% fewer bushels per hectare or acre compared to identical conventional varieties grown under similar conditions.
• The adoption of RR soybeans has been more extensive in Argentina than in the U.S., reaching over 95% in 2002 in Argentina compared to approximately 75% in the U.S.
• Glyphosate use in Argentina is significantly more intensive than in the U.S.; in 2000, per-hectare applications on RR soybeans were approximately 2.76 kilograms in Argentina versus about 1 kilogram in the U.S.
• The use of RR technology facilitates no-till farming, which dramatically reduces soil erosion on highly-erodible land, lowering erosion rates from 50 or more tons per acre to under 10 tons.
• There is evidence that glyphosate application in RR soybean systems impairs root development and nitrogen fixation, with yield losses of up to 25% observed in less fertile soils or under drought stress.
• Research indicates a buildup of Fusarium fungi in fields planted with RR soybeans over multiple years, which may be linked to root exudates triggered by glyphosate application.
• The genetic transformation of RR soybeans may impair the plant's immune response by depressing the synthesis of aromatic amino acids like phenylalanine, which is critical for triggering Systemic Acquired Resistance (SAR).
• Bt cotton has markedly reduced insecticide use in several U.S. states, particularly for the budworm-bollworm complex, whereas Bt corn has had little to no impact on corn insecticide use.
• Over-reliance on a single weed management strategy, such as glyphosate, has led to shifts in weed species and the emergence of resistant weeds, such as glyphosate-resistant horseweed discovered in Delaware in 2000.

APA

Benbrook, C. (2003). Economic and Environmental Impacts of First Generation Genetically Modified Crops. International Institute for Sustainable Development. https://www.iisd.org/system/files/publications/tkn_firstgen_gmo_us.pdf

Chicago

Benbrook, Charles. Economic and Environmental Impacts of First Generation Genetically Modified Crops. International Institute for Sustainable Development, 2003. https://www.iisd.org/system/files/publications/tkn_firstgen_gmo_us.pdf.

Wikipedia

{{cite report |last1=Benbrook |first1=Charles |title=Economic and Environmental Impacts of First Generation Genetically Modified Crops |publisher=International Institute for Sustainable Development |date=2003 |url=https://www.iisd.org/system/files/publications/tkn_firstgen_gmo_us.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{benbrook2003economic, author = {Benbrook, Charles}, title = {{Economic and Environmental Impacts of First Generation Genetically Modified Crops}}, institution = {International Institute for Sustainable Development}, year = {2003}, url = {https://www.iisd.org/system/files/publications/tkn_firstgen_gmo_us.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }