Abstract:
The use of plant growth promoting rhizobacteria has been proven to be an environmentally sound way of increasing plant growth. Pseudomonas fluorescence is an important group of Plant growth promoting rhizobacteria and the most abundant microorganism in the rhizosphare. The purpose of this study was to assess the role of Pseudomonas fluorescence on growth promoting of maize, wheat and sorghum. The study design was complete random design based on laboratory and pot experiment. The study was conducted at University of Gondar, by collecting rhizosphare soil samples from fields of growing of cereal crops which are found at around Debark. Three isolates were effectively identified as Pseudomonas fluorescence strains. Mixtures of Pseudomonas fluorescence strains showed significant increases in all the parameters (shoot height, shoot fresh weight, shoot dry weight, root length and root dry weight) measured. The isolates induced inhibition zones ranging from 10-29mm towards the Fusarium oxysporium. The highest germination percentage (91.66%) was observed with the seeds inoculated with the combination P.f1, P.f2 and P.f3. In pot experiment, it was observed that inoculation with Pseudomonas fluorescence strains combinations significantly increased overall growths of maize, wheat and sorghum. The highest increased shoot height of those cereal crops achieved by treatment one (T1), which increased shoot height by 24.33cm and 17.67cm for maize and wheat respectively and also for sorghum 15.00cm achieved by treatment one (T1) and two (T2). Combination of introductions of Pseudomonas fluorescence isolates is very effective in promoting growth than single isolates. Inoculation of Pseudomonas fluorescence strains as bio fertilizer will be useful in increasing cereal productivity and contribute to tackling food deficits in Ethiopia. There is a very limited knowledge of the use of PGPR in agriculture in Ethiopia. The current study therefore contributes for utilizing plant-associated bacteria to develop productivity of organic farming and sustainability in Ethiopia.
