Surface sterilization and isolation of culturable Bacteria:
One gram soil sample from LARS, SARS, and BS was serially diluted in 9 ml sterile deionized water. Similarly, 1 g of sterilized roots were crushed using a mortar and pestle and serially diluted in 9 ml sterile deionized water to isolate endophytes. 100 μ l homogenate from each dilution (up to 10-6 for soil samples and 10-4 for root samples) were plated in triplicate on four different culture media. Nutrient agar (NA) (general-purpose media), King’s B agar (KB) (selective media), Pikovskaya’s agar (PKA) (selective media), Jensen’s agar (JA) (selective media). The growth of colonies on the selective media, i.e., PKA, JA, KB, was assumed to reflect the functional traits of the isolates. For example, PKA bacterial isolates with phosphate solubilization function, JA nitrogen-fixing activity, and KB pseudomonas bacteria, respectively. Agar plates were incubated at 28 ºC and observed for bacterial growth for 48 hours. The number of colony-forming units (cfu) from each replicate was counted under a colony counter and reported in log cfu g-1 soil or roots. Isolates were grouped based on their unique colony morphologies such as colour, shape, size, etc. Randomly selected isolates of different morphologically distinct groups were further cultured individually on agar plates for pure colonies and purified for the further 16s RNA gene-based identified.