Study: GMO crops could help offset climate change impacts

By Joan Conrow

November 30, 2018

New research suggests that the type of yield gains made possible by genetic engineering (GE) will be needed to offset climate change impacts on agriculture.

The researchers said their study, published yesterday in Environmental Research Letters, has “important implications for regions lagging in the adoption of new technologies which could help offset the detrimental effects of climate change.”

Though agricultural productivity in Africa and Asia is predicted to be heavily impacted by climate change, political leaders in those regions have been slow to adopt GE technology in the face of intense opposition driven primarily by western-funded anti-GMO activists.

However, this new study suggests that nations may not have the luxury of avoiding new technology if they want to ensure food security in a warming world.

“The growth rate of crop yields in the coming decades will have serious implications for the global food supply under climate change,” the researchers wrote. “Our results suggest that US maize yields could stagnate under a business-as-usual scenario even with bold assumptions about the sustained growth in crop yields. This has serious implications for other crops and countries as well, as there are many large, economically relevant regions in the world where technology adoption lags and the use of GE crops are prohibited.

“If the relative yield gains estimated here are any indication of the potential for other crops and/or regions, then the adoption of new technologies such as GE varieties may constitute a potentially fruitful adaptation strategy for counterbalancing the effects of climate change,” the study concluded.

Researchers Ariel Ortiz-Bobea, assistant professor of applied economics and management at Cornell University, and Jesse Tack, associate professor of agricultural economics at Kansas State University, used modeling to evaluate the impact of climate change on US maize yields in light of the productivity gains associated with the period of rapid adoption of GE seeds.

“We find that yield gains on the order of those experienced during the adoption of GE maize are needed to offset climate change impacts under the business-as-usual scenario, and that smaller gains, such as those associated with the pre-GE era in the 1980s and early 90s, would likely imply yield reductions below current levels,” the researchers wrote. “Although this study cannot identify the biophysical drivers of past and future maize yields, it helps contextualize the yield growth requirements necessary to counterbalance projected yield losses under climate change.”

The research is important because “without substantial gains in productivity, the rising global demand for food could lead to higher food prices thereby incentivizing conversion of rainforests, wetlands, and grasslands to farmland,” the economists wrote.

The study reviewed production data from 500 counties in eight Midwestern states — Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, Ohio and Wisconsin — that comprise America’s “corn belt.” The maize crops there are mostly rain-fed. Using climate change models, the researchers then calculated county-level climate change impacts on yields in percentage terms.

They found that maize yield trends increased by almost 70 percent around the period of rapid adoption of GE seeds, and that “technological change has impacted different regions very differently. That is, while new technologies such as GE seeds are widely adopted, benefits can vary substantially across alternative growing conditions associated with local biotic and abiotic factors and interactions thereof.”

The researchers also noted that “emerging technologies in genome editing as well as an increased emphasis on abiotic stress tolerance (e.g. drought tolerance) could help maintain or even accelerate recent yield growth trends.  In addition, the rise in computing power and fine-scale data collection and analysis may pave the way for a digital revolution that may also contribute to such trends through enhanced precision agriculture. It remains to be seen whether these technological revolutions and the legal framework to reward such innovations and protect intellectual property rights will unfold rapidly enough to counterbalance the projected effects of a changing climate.”

The authors did note two caveats: “First, while our trend analysis identifies a yield trend increase around the time of rapid adoption of GE seeds, our study is unable to identify the biophysical source of this change. There could be other confounding factors that generated yield gains parallel to the introduction of GE maize in the US such as the adoption of precision agricultural tools such as high-speed precision planters and auto-steer tractors. Second, our climate change projections do not factor in fertilization effects of increased atmospheric CO2 levels nor behavioral adaptation to climate change. These additional factors could result in potentially more optimistic impacts.”