Fig. 1

The intricate tripartite interplay among PGPR, host plants, and pathogenic microorganisms within the rhizosphere. Within this visual representation, plants release phytohormones as a means of attracting PGPR, effectively guiding them toward the root system. Meanwhile, the communication network established among PGPR (gram-positive or negative) functions to suppress the activity of invading pathogens, simultaneously promoting plant growth through the production of phytohormones. In parallel, host plants activate their defense mechanisms, specifically triggering Induced Systemic Resistance (ISR), in response to potential threats posed by pathogenic organisms. Abbreviations: VOCs = Volatile Organic Compounds; AHLs = Acyl-homoserine Lactones; AL-2 = Autoinducer-2; QS = Quorum Sensing; HCN = Hydrogen Cyanide; MAMPs = Microbe-Associated Molecular Patterns