Plant Growth-Promotion Activities of Endophytic Bacteria Associated with The Medicinal Plant Areva javanica (Family: Amaranthaceae).

Abstract

ENDOPHYTES are ubiquitous microorganisms that reside within plant tissues and contribute to plant growth and well-being. However, knowledge about plant growth-promoting endophytes, particularly in medicinal plants, remains limited. This study aimed to isolate and characterize putative endophytic bacteria from Aerva javanica in the Albaha region of Saudi Arabia. Endophytic bacteria were isolated from the roots, stems, leaves, and inflorescences of the plant. The selected isolates exhibited plant growth-promoting traits such as indole-3-acetic acid (IAA) production, ammonia formation, and phosphate solubilization. Additionally, they demonstrated varying capacities to produce lytic enzymes and hydrogen cyanide (HCN), suggesting potential antifungal properties. The isolates also exhibited tolerance to different stress conditions. Partial sequencing of the 16S rRNA gene was used for bacterial identification, and NCBI BLAST analysis revealed that the isolates belonged to the genera Micrococcus, Enterobacter, Pseudomonas, Delftia, and Bacillus. These findings highlight the potential of endophytic bacteria to enhance plant growth and protect crops from soil-borne diseases