Isolation and characterization of endophytic bacteria from ginger (Zingiber officinale Rosc.)
Abstract
The present investigation was aimed to isolate and characterize endophytic bacteria from Ginger (Zingiber officinale Rosc.) plant with salt tolerance, antifungal activity, and plant growth-promoting traits. A total of 15 endophytic bacteria were isolated from ginger by standard microbiological culture methods. Nine endophytic bacterial isolates (GS1, GS2, GS3, GS4, GS6, GS7, GS8, GS9, and GS11) showed salt tolerance up to 10% NaCl concentration. Six isolates showed salt tolerance up to 7-8% NaCl concentrations. Studies on plant growth-promoting activity suggested that four endophytic bacterial isolates (GS2, GS5, GS8, and GS10) were positive for IAA production, siderophore production, and phosphate solubilization activity. All the endophytic bacterial isolates were screened for the production of enzymes. The result of the study revealed that maximum isolates have positive protease activity and this was followed by lipase and cellulase activities. While studying the antifungal activity of the bacterial isolates, it was determined that eight isolates showed antifungal activities against fungal strains F. globosum 905 and F. graminearium 611. Four endophytic bacterial isolates (GS4, GS6, GS8, and GS9) had antifungal activity against several fungal strains. The results indicated that endophytic bacteria were isolated from ginger with salt-tolerant and plant growth-promoting activities that were reported, that could be used as inoculants to establish a sustainable ginger production system.