Native Plant Growth-Promoting Microorganisms (PGPMs) Inoculation Improves Phenological Stability and Productivity in Maize Hybrids

Abstract

This study aimed to evaluate the growth-promoting effects of a dual bacterial consortium (P. megaterium and E. cloacae) on six maize hybrids under field conditions in the Yaqui Valley, Mexico. Three treatments were applied: seed immersion before germination (T1), drench application 15 days after emergence (T2), and a control without consortium (T3). Phenology, starch mobilization, NDVI (Normalized difference vegetation index), leaf GA3 (Gibberellic acid) and ABA (Abscisic acid) levels, biomass, and grain yield were evaluated. Consortium application (T1 or T2) allowed plants to complete phenological stages normally, while control plants showed accelerated development after flowering, reducing protein and carbohydrate mobilization by around 50%. In treated plants, mobilization rates remained above 85%. NDVI values were significantly higher in T1 and T2, with no differences between them. GA3 and ABA levels stayed balanced in T1 and T2, but shifted in T3, leading to premature development. Biomass and grain yield increased by 34% and 37%, respectively, in consortium-treated plants. The consortium’s positive effects were independent of maize genotype, and both application methods were effective. Overall, this study demonstrates the practical potential of using bacterial consortia to improve maize growth and yield under field conditions. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2025.