Gene-Edited Soil Bacteria: A Step Toward Sustainable Nitrogen Supply for Corn

 

Summary:

Gene-edited bacteria could pave the way for a revolutionary nitrogen source for corn production. A study by researchers at the University of Illinois Urbana-Champaign demonstrates that these modified bacteria can supply up to 35 pounds of nitrogen per acre during early growth stages, potentially reducing reliance on synthetic fertilizers.

FULL STORY:

Soybean's symbiotic relationship with nitrogen-fixing bacteria has long been envied by corn growers. However, recent advances in gene-editing technology offer hope for corn to similarly tap into atmospheric nitrogen. Researchers have shown that engineered bacteria, when applied to cornfields, can provide the crop with biologically fixed nitrogen, equivalent to 35 pounds per acre, during early growth stages.

The study, conducted over three field seasons, used Pivot Bio's products, PROVEN® and PROVEN® 40, which include modified soil bacteria capable of enhancing nitrogen fixation. These bacteria colonize corn roots and supply plant-available nitrogen directly where it is needed.

Although the average yield increase was modest—about 2 bushels per acre—at moderate nitrogen rates, the inoculant increased yields by 4 bushels per acre. The nitrogen contribution, which started strong during early growth, diminished to about 10 pounds per acre by the end of the season, indicating that synthetic fertilizers are still essential for optimal yields.

Despite current limitations, researchers believe this technology holds promise. It could serve as a supplementary nitrogen source, especially in areas prone to nutrient loss or under-fertilized fields. The approach might also help reduce "insurance nitrogen," the practice of over-applying fertilizer as a safeguard, thus benefiting both farmers and the environment.

“While complete replacement of synthetic nitrogen is still a long way off, these findings demonstrate that microbial inoculants could become an essential tool in sustainable agriculture,” said study co-author Fred Below.

Reference:

Logan P. Woodward, Connor N. Sible, Juliann R. Seebauer, Frederick E. Below. Soil inoculation with nitrogen‐fixing bacteria to supplement maize fertilizer need. Agronomy Journal, 2024; 117 (1) DOI: 10.1002/agj2.21729