Genomic and functional Characterization of Pseudomonas oryzihabitans JQ13 from mulberry Unveils its dual plant Growth-Promoting potential and antagonistic activity against Fusarium oxysporum

• Pseudomonas oryzihabitans JQ13, a PGPR, was isolated from mulberry. • JQ13 colonizes mulberry roots/stems, enhancing seedling vigor without disease symptoms. • Genome analysis reveals genes for IAA, siderophores, ACC deaminase, and antifungals. Mulberry ( Morus spp.) is a widely distributed species with rich genetic diversity and serves as the primary food source for silkworms. The broad adaptability and genetic diversity of mulberry contribute to a rich and diverse community of endophytes within them. In this study, five endophytic bacterial strains were isolated from mulberry branches. Plate assays showed that these strains exhibited plant growth-promoting traits, such as indole-3-acetic acid (IAA) and siderophore production, as well as antagonistic activity against Fusarium oxysporum. Greenhouse experiments further demonstrated that repeated inoculation enhanced the vigor of mulberry seedling with Pseudomonas oryzihabitans JQ13. Microscopic observation of a fluorescently labeled JQ13 confirmed its root colonization and stem microcolony formation without disease symptoms. To investigate its functional basis, the complete genome of JQ13 was sequenced, revealing a 5.08 Mb chromosome encoding 4,641 protein-coding genes. Functional annotation identified genes related to IAA biosynthesis, siderophore production, nutrient metabolism, ACC deaminase activity, antifungal factors, chemotaxis, and biofilm formation. These findings established JQ13 as a versatile plant symbiont with potent growth-promoting and antifungal capabilities highlighting its promise as a biocontrol agent while providing new insights into endophyte–host interactions.