Gibberellins production by fluorescent Pseudomonas isolated from Rhizospheric soil of Malus and Pyrus

Little is known about the gibberellins producing fluorescent Pseudomonas (FP) diversity associated with rhizosphere of Malus (apple) and Pyrus (pear). Therefore, the objective of the present study was to investigate gibberellins production by Pseudomonas sp., a major component of rhizobacteria with multiform and diverse activities, which alter the structure or life processes of plants to improve quality, increase yields and facilitate harvesting. In the present investigations, thirty Pseudomonas isolates were isolated from the rhizosphere of Pyrus and Malus and were screened for gibberellins production (25–60 μg/ml). Four strains viz PN-4-SAN, PN-10-SAN, AN-2-NAG and AN-4-NAG were selected on the basis of their higher gibberellins production. The maximum production of gibberellins was observed at 72 h incubation period in nutrient broth at pH 7.0 under shaken condition at 28°C. Gibberellins were extracted, purified and evaluated by thin layer chromatography and specific bioassay method.

Highlights

• Pseudomonas isolates were obtained from rhizospheric soils of apple and pear.

• Four efficient gibberellins producing isolates were screened.

• Extracted gibberellins were characterized.