Pre-inoculation of corn and soybean seeds with Biofix Azos: Assessing viability, survival, and agronomic efficiency

New technologies, such as pre-inoculation with protective additives have been developed to optimize the inoculation of beneficial bacteria like Azospirillum brasilense in crops, and represents a promising strategy to optimize the use of bio inputs and streamline field operations. This study evaluated the efficacy of inoculants of pre-inoculating corn seeds with Biofix Azos and soybean seeds with Biofix Azos and Biofix Protec, both performed 30 days before sowing. Four field trials were conducted in different edaphoclimatic regions of Brazil (GO, MG, SP, and PR) during the 2022-2023 season, to ensure greater reliability of the results. Standardized agronomic protocols, randomized block design, and statistical analyses were applied. The treatments of soybean and corn included seed pre-inoculation with Biofix Azos 30 days before sowing, compared to inoculation performed on the day of sowing, fertilization with 200 kg/ha of nitrogen, and a control without fertilization or inoculation. In corn, pre-inoculation with Biofix Azos demonstrated an increase in shoot dry mass, chlorophyll content, and grain nitrogen content, resulting in grain yield gains ranging from 2.8 to 7.7%, compared to the treatment inoculated on the sowing day. In soybeans, co-inoculation with Biofix Azos and Biofix Protec significantly increased nodulation, nodule dry mass, and nitrogen fixation, resulting in grain yield gains ranging from 6.0 to 7.6%, equivalent to the treatment inoculated on the sowing day. The results from pre-inoculation were equal to or superior to those achieved with inoculation on the sowing day. Laboratory tests confirmed the feasibility of pre-inoculation, demonstrating that bacteria maintained their viability for up to 30 days after treatment, even when combined with chemical products. These results indicate that pre-inoculation with Biofix Azos (corn) and Biofix Azos and Biofix Protec (soybean) is an effective strategy to increase grain yield and enhance the sustainability of corn and soybean crops, offering consistent benefits to farmers.