Fertilisation & Climate Change: Policy Risks & Seed Innovation
- Rising atmospheric carbon dioxide (CO₂) levels are increasingly recognized not just as a driver of climate change, but also as a significant, and often underestimated, contributor to agricultural...
- For decades, improvements in agricultural yields have been attributed to advancements in genetics, agronomy, mechanization, and input management.
- Plant physiologists have understood for over 200 years that increased CO₂ concentrations can accelerate photosynthesis, the process by which plants convert light energy into chemical energy for growth.
Rising atmospheric carbon dioxide (CO₂) levels are increasingly recognized not just as a driver of climate change, but also as a significant, and often underestimated, contributor to agricultural productivity. New data suggests that the “CO₂ fertilization effect” – the boost in plant growth resulting from increased CO₂ – has played a larger role in recent crop yield increases than previously accounted for in many European Union policy models.
For decades, improvements in agricultural yields have been attributed to advancements in genetics, agronomy, mechanization, and input management. Since the 1940s, wheat yields have tripled, and maize yields have increased sixfold, largely thanks to innovations within the seed sector. However, a recent working paper from the US National Bureau of Economic Research (NBER), published in December 2025, indicates that rising CO₂ levels have contributed substantially to this growth, potentially more than current models suggest.
The principle behind CO₂ fertilization isn’t new. Plant physiologists have understood for over 200 years that increased CO₂ concentrations can accelerate photosynthesis, the process by which plants convert light energy into chemical energy for growth. Commercial greenhouse operators routinely enrich their environments with CO₂ to enhance yields. The challenge has been accurately quantifying the effect in real-world agricultural settings.
Historically, estimates of CO₂’s impact have largely come from controlled experiments. However, the NBER study and accompanying satellite data analysis move beyond these controlled environments to measure CO₂’s effect where crops actually grow. This shift in methodology reveals a more significant impact than previously understood, particularly for key crops like wheat, maize, and soybeans.
The implications of this finding are considerable, particularly for European policymakers. Current EU policies aimed at mitigating climate change may be overstating the potential damage caused by rising temperatures if they fail to adequately account for the offsetting benefits of CO₂ fertilization. This could lead to misdirected policies and an undervaluation of the role of seed-sector innovation in ensuring future food security.
Ignoring the CO₂ fertilization effect could have several consequences. Firstly, it may lead to overly pessimistic projections of climate change’s impact on agriculture, prompting unnecessarily stringent regulations. Secondly, it could diminish investment in the seed sector, which is crucial for developing crop varieties that are not only higher-yielding but also more resilient to climate variability and other environmental stresses. The seed sector has been instrumental in delivering varieties adapted to farmers’ needs, and continued innovation is vital.
The study highlights the need for more sophisticated climate and agricultural models that accurately incorporate the CO₂ fertilization effect. These models should consider the complex interactions between CO₂, temperature, water availability, and other factors that influence crop growth. Research is needed to understand how different crop varieties respond to elevated CO₂ levels and to identify opportunities for breeding crops that can maximize the benefits of CO₂ fertilization.
While the CO₂ fertilization effect offers a potential buffer against the negative impacts of climate change, it is not a substitute for reducing greenhouse gas emissions. The long-term sustainability of agriculture depends on mitigating climate change and adapting to its unavoidable consequences. However, recognizing the positive role of CO₂ in boosting crop yields is essential for developing effective and evidence-based policies.
The findings also underscore the importance of continued investment in agricultural research and innovation. Developing crop varieties that are both resilient to climate change and capable of maximizing the benefits of CO₂ fertilization will be crucial for ensuring global food security in the decades to come. This includes exploring technologies like genetic modification and precision agriculture, as well as promoting sustainable farming practices that enhance soil health and water use efficiency.
Agricultural and innovation policies are already being shaped by the need to address climate change. A study published in , in Environmental Science and Pollution Research International, examined the role of such policies in helping farmers meet the challenges posed by a changing climate. The EU supports agricultural policies aimed at promoting sustainability, but the integration of CO₂ fertilization effects into these policies remains an area for improvement.
The contribution of seed and crop technologies to climate change mitigation and adaptation is also gaining recognition. A report from CropLife International highlights the significant impact of these technologies on the sustainability of crop production, noting that accumulated impacts of new technologies, especially genetically modified crops, are leading to substantial contributions.
a comprehensive approach to agricultural policy must consider the complex interplay between climate change, CO₂ fertilization, and technological innovation. By acknowledging the benefits of rising CO₂ levels while simultaneously working to reduce greenhouse gas emissions, policymakers can create a more sustainable and resilient food system for the future.