How genetically modified (GM) crops have reduced global agriculture’s greenhouse gas emissions

Crop biotechnology has significantly reduced agriculture’s greenhouse gas (GHG) emissions by helping farmers adopt more sustainable practices such as reduced tillage, which decreases the burning of fossil fuels and retains more carbon in the soil according to my recently published study1.

Had GM crops not been grown in 2020, for example, an additional 23.6 billion kilograms of carbon dioxide would have been emitted into the atmosphere, which is the equivalent of adding 15.6 million cars on the roads.

The peer-reviewed paper examined changes in farming practices arising from growing GM crops between 1996 and 2020 on global GHG emissions. The three main GHGs of relevance to agriculture are carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4).  The scope for GM crops contributing to lowering levels of GHG comes from two principal sources:

a. Reduced fuel use from fewer herbicide or insecticide applications;

b. The use of ‘no-till’ (NT) and ‘reduced-till’ (RT) farming systems collectively referred to as conservation tillage, has increased significantly with the adoption of genetically modified herbicide-tolerant (GM HT crops).  The GM HT technology has improved farmers’ ability to control weeds, reducing the need to rely on soil cultivation and seed-bed preparation as means to get good levels of weed control. The advantages of conservation tillage include lower fuel costs, reduced labour requirements associated with soil preparation, enhanced soil quality, and reduced levels of soil erosion, resulting in more carbon from crop residues remaining in the soil, which leads to lower GHG emissions, improved levels of soil moisture conserving and reduced soil temperature fluctuations from the insulating properties of crop residues.

Read the full article on the Genetic Literacy Project.