Pathogen Management in Glycyrrhiza glabra: Microbial Interactions and Phylogenetic Insights

Abstract

The plant-associated microbial communities are crucial for understanding their roles in enhancing plant health and productivity. This research aimed to isolate and characterize bacterial strains from the roots of Glycyrrhiza glabra L. using 16S rRNA gene sequencing to explore their phylogenetic relationships and functional potential. Root samples were collected from the Gulistan phytogeographic region, and bacterial strains were isolated through serial dilution and cultured on nutrient agar. Genomic DNA was extracted, and 16S rRNA sequencing was performed to identify the isolates, followed by phylogenetic analysis using MEGA X software. The results revealed three dominant Bacillus species: Bacillus licheniformis, Bacillus subtilis and Bacillus halotolerans. The strains exhibited significant enzyme activities, including protease, amylase and cellulase production, suggesting their roles in organic matter degradation and nutrient cycling. Furthermore, greenhouse trials demonstrated enhanced plant growth parameters such as root length, plant height and biomass, reflecting their potential as plant growth-promoting rhizobacteria (PGPR). Antibiotic production assays indicated their capacity for biocontrol against pathogens, reinforcing their role in plant disease suppression. This study emphasizes the ecological significance of Bacillus spp. in sustainable agriculture and their potential application as biofertilizers and biocontrol agents. Future research should focus on field trials and metabolomic analysis to elucidate the molecular mechanisms underlying the beneficial interactions, further optimizing their use in crop improvement strategies.