Teosinte-Derived SynCom and Precision Biofertilization Modulate the Maize Microbiome, Enhancing Growth, Yield, and Soil Functionality in a Mexican Field

Juan Alfredo Hernández-García ¹ Julio S Bernal ² Sanjay Antony-Babu ² Lourdes Villa Tanaca ¹ Cesar Hugo Hernández-Rodríguez ¹ Esaú De La Vega Camarillo ^1*

• ¹ National School of Biological Sciences, National Polytechnic Institute, Mexico City, México, Mexico
• ² Texas A&M University System, College Station, Texas, United States

Modern agriculture faces the challenge of optimizing fertilization practices while maintaining soil resilience and microbial diversity, both critical for sustainable crop production. This study evaluated the effects of conventional fertilization (urea-based and phosphorus fertilizers applied manually via backpack sprayers or drone-assisted precision delivery) and biofertilization (a SynCom derived from teosinte-associated microbes, composed of Serratia nematodiphila EDR2, Klebsiella variicola EChLG19, Bacillus thuringiensis EML22, Pantoea agglomerans EMH25, Bacillus thuringiensis EBG39, Serratia marcescens EPLG52, and Bacillus tropicus EPP72) on soil microbial community structure and plant performance. High-throughput sequencing showed significant shifts in bacterial and fungal communities across treatments. Untreated soils were dominated by Enterobacteriaceae (>70%), particularly Enterobacter and Klebsiella, with limited microbial diversity. Conventional fertilization gradually reduced Enterobacteriaceae abundance while increasing Pseudomonas and Lysinibacillus populations. Drone-assisted fertilization showed similar trends but notably enhanced the growth of Acinetobacter and Rhizobiales. Biofertilization treatments led to the most pronounced microbial shifts, reducing Enterobacteriaceae below 50% while significantly increasing beneficial taxa such as Bacillus, Pantoea, and Serratia. Network analysis demonstrated increased microbial interaction complexity across treatments, with Bacillus emerging as a keystone species. Drone-assisted biofertilization fostered intricate microbial networks, enhancing synergistic relationships involved in nutrient cycling and biocontrol. However, maintaining the stability of these complex microbial interactions requires careful monitoring. These findings provide key insights into how precision biofertilization, leveraging teosinte-derived microbial consortia, can sustainably reshape the maize microbiome, improving crop performance and soil resilience.