A new study by the University of Illinois Urbana-Champaign has found that gene-edited bacteria can help corn absorb up to 35 pounds of nitrogen from the air, potentially reducing reliance on synthetic fertilizers.
Corn farmers might soon have a sustainable alternative to synthetic nitrogen fertilizers, thanks to a new study conducted at the University of Illinois Urbana-Champaign. Researchers have discovered that gene-edited bacteria can supply up to 35 pounds of nitrogen per acre to corn plants during their early growth stages, which could reduce the crop’s dependency on traditional fertilizers.
In the study, scientists tested products from Pivot Bio named PROVEN and PROVEN® 40. These biotechnological breakthroughs involve soil bacteria engineered to enhance a key gene involved in nitrogen fixation.
When applied at planting, these bacteria colonize the corn roots and convert atmospheric nitrogen into a form usable by the plants.
“To replace all synthetic nitrogen would certainly be something. Maybe 100 years from now we will have found the microbes and genetic tweaks to get close to that goal, but these microbes are not there yet. However, we have to start somewhere, and this work demonstrates nitrogen-fixation for corn has potential,” co-author Connor Sible, a research assistant professor in the Department of Crop Sciences at Illinois, said in a news release.
To test the efficacy of these bacterial products, researchers implemented them over three field seasons, applying standard agronomic practices and nitrogen fertilizers at varying rates. Their goal was to address gaps in the existing research concerning the effectiveness and timing of biologically-fixed nitrogen.
“There is a lack of peer-reviewed published data to support this claim. There is also no research estimating the magnitude of nitrogen replacement values and when in the growth cycle that additional nitrogen is accumulated,” added Logan Woodward, who completed the study as a doctoral student at Illinois. “Our objective was to fill those knowledge gaps.”
The results were promising, showing a modest yet positive yield increase. Across all nitrogen fertilizer rates, the inoculant boosted corn growth, nitrogen accumulation, kernel number and yield by an average of 2 bushels per acre.
At moderate nitrogen rates, the yield improved by 4 bushels per acre, equating to 10-35 pounds of nitrogen per acre of fertilizer.
“The overall yield response was positive, but modest. The 35 pounds of fertilizer equivalent during early growth was down to about 10 by season’s end,” senior author Fred Below, a crop sciences professor, said in the news release. “Clearly, there is still a need to fertilize. You need enough nitrogen to build a happy and healthy plant, as a healthy plant can then produce the root sugars needed to feed the microbes.”
Despite the current inability to fully replace synthetic fertilizers, the research team sees significant potential in this technology. With further development, gene-edited bacteria could be tailored to deliver even greater benefits.
“Every farm has areas of the field where the soil does not provide enough nitrogen or the fertilizer was lost or unavailable, so a microbial inoculant to provide a third source of nitrogen could help,” Sible added. “Sometimes corn fields receive ‘insurance nitrogen’ where an extra 20 pounds is supplied in case it is a year prone to nitrogen loss. Perhaps a nitrogen-fixing inoculant can reduce the need for those extra 20 pounds, and this could have a large impact when summed across all Corn Belt acres.”
This research, published in Agronomy Journal, offers an innovative step toward more sustainable agriculture, potentially transforming how corn farmers manage nitrogen fertilizers.