Genetic and Functional Diversity of Bacterial Strains Associated with Prunus persica (L.)

Abstract

Aims: This study aimed to evaluate the genetic and functional diversity of bacteria associated with the surfaces of Prunus persica (L.) Batsch.
 Methodology: A total of 15 peach samples from various areas of Lahore city were collected and processed according to standard microbiological protocols. The final taxonomic status of bacterial strains was confirmed by 16S rRNA gene sequencing. Bacterial strains were screened for plant growth-promoting attributes that included auxin production, phosphate, and zinc solubilization, and hydrogen cyanide (HCN) production. Antimicrobial activity of strains was also evaluated. In pot trials, strains were evaluated for their role to enhance plant growth.
 Results: Analysis showed that bacterial isolates belonged to Bacillus, Staphylococcus, Klebsiella, Enterobacter, and Providencia genera. A strain KS 22 of Staphylococcus sciuri showed the highest production of auxin. In terms of antibiotic susceptibility, B. aerius KS 8 exhibited a pattern of sensitivity toward norfloxacin, amoxicillin, and clavulanic acid. For pot trials with cauliflower under laboratory conditions, S. sciuri KS 22 showed 3.1 folds increase in shoot length. In the case of tomato, P. rettgeri KS 23 recorded around 1.8 folds increase in shoot length over water-treated control. On the other hand, for cauliflower, around 1.3 folds increase in root length was exhibited by B. aerius KS 8, P. rettgeri KS 23, and E. cloacae KS 29. For tomato, B. aerius KS 8 showed 1.6 folds increase in root length in comparison to control. Under natural conditions, for cauliflower, the highest increase in shoot length was exhibited by P. rettgeri KS 23 and E. cloacae KS 29.
 Conclusion: Finally, it has been concluded that bacterial strains B. aerius KS 8, S. haemolyticus KS 9, S. sciuri KS 22, P. rettgeri KS 23, and E. cloacae KS 29 exhibited plant growth promotion in pot trials.