Isolation and characterization of streptomycetes with plant growth promoting potential from mangrove ecosystem

A total of 66 actinomycetes isolates were isolated from mangroves of Andhra Pradesh, India, using various enrichment techniques and pre-treatments. The samples were collected from Coringa mangrove ecosystem and pre-treated by enrichment with CaCO₃, sodium dodecyl sulphate and phenol, plated on the media supplemented with cycloheximide (50 mg/ml), nystatin (25 mg/ml) and nalidixic acid (50 mg/ml).The population count of actinomycetes fluctuated from 1.9 × 10⁵ to 8.0 × 10⁵/g soil. Out of the isolated 66 actinomycetes, 8 isolatespossessing plant growth promoting potential were further studied and characterized by physiological and biochemical traits and identified by 16S rRNA gene sequencing as different species of Streptomycetes genera.