Efficacy Of P. Putida And P. Fluorescens Isolates

P. putida and P. fluorescens isolates were cultured in 250 ml Laurea Broth (LB) medium at 30±1 ºC for 36 h in an incubator shaker at 150 rpm. The culture was then poured into 50 ml falcon tubes and centrifuged for 10 min. at 6000 ×g at 4 ºC. The pellet was washed thrice in 15 ml distilled water and centrifuged. Then it was dissolved in distilled water and the optical density (O.D) of the culture was set at position-1 at 600 nm=107–108 colony forming units (CFU) ml-1 for inoculation (Bhuvaneswari et al. 1980). Maize B73 (Z. mays L.) seeds were then inoculated with selected bacterial cultures for 2 h, while control plants group was mock-inoculated with sterilized water only.
1.3. Plant Growth and Drought Stress Conditions
A pot experiment was conducted to compare the efficacy of two …show more content…
Maize B73 variety seeds were surface disinfected with 75 % ethanol for 3 min, and then treated with sodium hypochlorite (2 %) for 5 min. The washing was repeated with sterile distilled water for 3 times (2 min). The efficacy of surface sterilization was checked by plating the seeds and aliquots of the final rinsing sterilized distilled water onto LB plates. When no colonies were observed on the LB plates, seeds were considered to be successfully surface disinfected. Seeds were incubated in bacterial suspensions (P. putida and P. fluorescens) for 12 hours. For the control group, seeds were treated with sterilized water as a mock inoculation. Three inoculated seeds were sown in each cylindrical shape pot having 6 inch diameter and were thinned to one plant after one week of germination of seedlings. Each pot contained ~2 kg of the sterilized growth media