Genetic engineering: improving biofertilizers to increase soybean productivity

Table of Contents

Genetic editing of a commercial bioinoculant commonly used in Argentina, carried out by an international team led by a CONICET scientist, could increase soybean productivity by up to six percent

Nicolás Ayub is working on the evaluation of modified biofertilizers. Credit: Nicolás Ayub

An international scientific team, led by CONICET researcher Nicolás Ayub, achieved a genetic improvement of a commercial biofertilizer commonly used in Argentina, which could increase soybean productivity by approximately 6 percent. Using the CRISPR/Cas9 technique, the researchers genetically edited the E109 strain of the nitrogen-fixing bacteria Bradyrhizobium japonicum and managed to increase its impact on crop productivity. “We are the first group in the world to successfully perform CRISPR/Cas9 editing in elite bacteria of agronomic importance,” highlighted Ayub, who works at the Institute of Agrobiotechnology and Molecular Biology (GV IGEAF IABIMO, CONICET-INTA).

As they are free of DNA from other organisms, the edited bacteria would not be considered genetically modified organisms (GMOs) under the laws of various food-producing countries, such as Brazil, the United States, China, India, Indonesia, Bangladesh, and Australia, which would facilitate the possibility of their commercialization and application by agricultural producers in a relatively short time.

Silvina Brambilla (left) and Laura Serrantes (right) examine the response of soybeans to modified biofertilizers. Credit: Nicolás Ayub.

The international platform for the improvement of biofertilizers, bioinsecticides, and biofungicides, led by the CONICET scientist that involves research institutes from Argentina, Brazil, Chile, Colombia, Spain, and Uruguay, is funded by FONTAGRO, a co-financing mechanism for the development of agricultural technology in Latin America, the Caribbean, and Spain.

More productivity, lower costs
#

Beyond their impact on agricultural productivity, engineered biofertilizers are cheaper than chemical fertilizers, such as synthetic nitrogen. “In the last two decades, the cost of natural gas and its derivatives, such as synthetic nitrogen, has increased significantly, while crop prices have remained stable,” argued the CONICET researcher, who added, as an additional advantage, that bioinoculants do not generate environmental pollution.

Nicolás Ayub, project director. Credit: Nicolás Ayub

Compared to the use of unedited nitrogen-fixing bacteria (rhizobia), Ayub pointed out that while these have made a great contribution to agriculture, it has been more than two decades since new natural strains were found that surpassed their predecessors. “Strain E109, used to biofertilize soybeans, was isolated in the early 1990s, and no research group has been able to find one that surpasses it. So, evidently, in some crops we have reached a ceiling in traditional biofertilizer breeding, and we must apply new strategies if we want to continue improving their impact,” the researcher said. The use of the developed biofertilizers, in addition to allowing greater degradation of glyphosate and lower emissions of nitrous oxide, guarantees a greater contribution of nitrogen to the soil, making it possible to reduce the cost of fertilization in cereal rotations.

Luisa Galindo, a group collaborator, works in the laboratory. Credit: Nicolás Ayub

According to Ayub, the use of CRISPR/Cas9 as a genetic engineering technique, by not introducing any DNA elements from another organism into the biofertilizer to be optimized (as is the case with GMOs), could reduce the costs and timescale for the new technology to impact the agricultural sector. “With GMO technology, what you do is introduce genes from another organism into an organism, which give it a new capacity. With CRISPR/Cas9, what we do are specific nucleotide substitutions, analogous to changing a letter in a book, enhancing the capacity that the native genes of the biofertilizer already had,” Ayub said.

Researchers expect that, in approximately one year, the first generation of engineered biofertilizers for soybeans and alfalfa will be on shelves, “because they are registered like any traditional (non-GMO) biofertilizer.” They are also working on a second generation of engineered biofertilizers to replace synthetic nitrogen in cereals (wheat, corn, and rice), as well as on engineered probiotics to minimize methane emissions in livestock.

Bibliographic references
#

Serantes, L., Stritzler, M., Brambilla, S. et al. Genome editing of soybean inoculant using CRISPR/Cas9 system: enhancing agricultural sustainability. Plant Cell Tiss Organ Cult 157, 35 (2024). https://doi.org/10.1007/s11240-024-02764-y

Brambilla, S., Pascuan, C., Frare, R., Liebrenz, K., Pesquero, N., Ruiz, MJ, … & Ayub, N. (2025). Engineering a commercial soybean inoculant to efficiently degrade glyphosate. Rhizosphere , 101109. https://doi.org/10.1016/j.rhisph.2025.101109

Cardillo, ME, Brambilla, S., Liebrenz, K. et al. Genomic and physiological plasticity in natural variants of commercial soybean inoculants supports the non-GMO status of base-edited inoculants. Plant Cell Tiss Organ Cult 161, 26 (2025). https://doi.org/10.1007/s11240-025-03059-6

The article Ingeniería genética: mejorar biofertilizantes para aumentar la productividad agrícola, signed by Miguel Faigón was published in CONICET’s news section.

Contact [Notaspampeanas](mailto: notaspampeanas@gmail.com)