Characterization and Application of PGPR (Plant Growth Promoting Rhizobacteria) for Enhanced Climate-Resilient Crop Production in Sustainable Agriculture.

The PhD thesis explores the use of Plant Growth Promoting Rhizobacteria (PGPR) to improve the resilience of agricultural crops to salt stress. In general, it fits into a context that not only aims to corroborate knowledge in sustainable agriculture but also to address today's challenges related to climate change. Initially, the impact of salt elicitation was studied, to assess stress tolerance and promote the accumulation of phenolic compounds. Laterally, the biodiversity and activity of PGPR in conventional and organic agricultural systems was examined. Bacterial strains were found that were successful in reducing the negative effects of salinity through solubilization of phosphorus, production of IAA and siderophores. Finally, the study was extended to include PGPR strains isolated from extreme marine sediments, namely mangroves of Cartagena Bay in Colombia, demonstrating their potential as biostimulants. The results have allowed us to study a promising microbial consortium that, if added to saline soils, could significantly improve production and overall soil health, while reducing negative impacts on the environment.