Bacillus velezensis Genome sequencing. Bacillus velezensis

Root-associated microorganisms, such as plant growth-promoting rhizobacteria (PGPR) belonging to the Bacillus genus, play a crucial role in enhancing crop yield and health. In this study, a Bacillus strain was isolated from the rhizosphere soil of maize and identified as Bacillus velezensis D103. The objective of this research was to evaluate the potential of D103 as a PGPR. Laboratory tests revealed that D103 possessed the ability to fix nitrogen, dissolve inorganic phosphorus, dissolve potassium, synthesize indole acetic acid (IAA), ammonia, siderophores, amylase, protease, cellulase, beta-1,3-glucanase, and ACC deaminase, as well as demonstrating swimming and swarming motility, biofilm formation, and an antagonistic effect against pathogenic fungi. Genome mining approaches identified genes associated with growth promotion and biocontrol activities in D103. In a hydroponics experiment, treatment of maize with D103 suspension at a cell density of 103 CFU mL-1 resulted in the most pronounced growth stimulation of maize, with shoot length and total root length increasing by 43% and 148%, respectively. Collectively, this supports the potential use of D103 as a PGPR with positive efficacy in promoting maize crop growth.