Precision gene editing of rhizobia with CRISPR/Cas9 promises sustainable productivity gains and reduced fertilization costs
A multinational scientific collaboration led by Argentina’s National Institute of Agricultural Technology (INTA) has achieved a critical innovation in sustainable agriculture by editing rhizobia bacteria to enhance soybean productivity by 6%. The research, backed by INTA’s National Biotechnology Program and Fontagro, included scientists from Uruguay, Chile, Colombia, Spain, and Argentina.
Breakthrough in Nitrogen Fixation: Editing Rhizobia without Foreign DNA
The project used CRISPR/Cas9 gene editing technology to modify commercial rhizobia strains—E109 from Argentina and SEMIA5079 from Brazil—key microorganisms used in biological nitrogen fixation. Unlike conventional GMOs, these gene-edited rhizobia do not incorporate foreign DNA, thus qualifying as non-GMO under regulatory standards in major agricultural nations such as the U.S., China, Brazil, India, and Australia.
Nicolás Ayub, principal researcher at CONICET and IABIMO-INTA, noted that the process involved introducing a CRISPR/Cas9 plasmid and a specific guide RNA to the rhizobia genome, followed by plasmid removal. This ensures no transgene presence in the final inoculant product, a critical step for regulatory acceptance and global commercialization.
“This technology inhibits nitrogen loss from the soil, reducing fertilization costs in cereal rotations by up to 10%,” Ayub added.
A Non-GMO Advantage for Global Regulatory Acceptance
The absence of transgenic material makes the innovation particularly promising for rapid approval and commercialization across global markets. It circumvents the lengthy and often contentious GMO regulatory hurdles, providing a pathway for accelerated tech transfer to the productive sector.
Silvina Brambilla, INTA researcher and co-director of the project, emphasized that regulatory validation by CONABIA is underway to verify the equivalence of edited rhizobia with conventional inoculants.
Beyond Soy: Future Biofertilizer Applications in Cereal and Livestock Systems
This development marks the first time CRISPR/Cas9 has been successfully applied to commercial rhizobia with direct agricultural applications, beyond research-focused model bacteria.
Rhizobia reproduce asexually, making them impossible to improve via crossbreeding. The gene-editing approach updates decades-old strains and opens new frontiers for enhancing soil phosphorus solubility, methane degradation, pest control, and nitrogen fixation in cereals.
“This is a key tool for sustainable productivity—producing more with fewer inputs,” Brambilla noted.
