Growth Response of (<i>Coffee Arabica)</i> to Plant Growth Promoting Rhizobia (PGPR) Inoculant Collected from Rhizosphere

Plant growth promoting rhizobia are beneficial bacteria that colonize plant roots and recover plant growth through wide variety of mechanisms. Productivity of coffee crop in Ethiopia is very low (0.7 ton ha-1 green coffee) as compared to other coffee producing countries. The low level of productivity of the crop stems from poor management of the plant during the initial stage of establishment in the field. The PGPR or Co- inoculant of PGPR and AMF can advance the nutrient use efficiency of plants. The aim of this study was to isolate, characterize (PGPR) and evaluate the Plant Growth Promoting Rhizobacteria inoculation effect on growth of coffee seedlings. Rhizosphere soil Sample was collected from Guwanguwa District Oromiya region. Samples were collected from growing coffee seedling rhizosphere. Random sampling was used to collect soil samples data to isolate PGPR using serial dilution methods. Isolates were allowed for d/f biochemical and physiological test. Each sample was designed in triplicate during laboratory experimentation to avoid variation. Most isolates were efficient in production of IAA, Phosphate solublization, Siderophore production, Hydrogen cyanide and Ammonia production. (PGPR) Isolates were also efficient to show significant effect on growth and growth related parameters of coffee seedling. PGPR inoculated coffee plant showed significance difference at (P≤0.05) compared to control group. (PGPR) isolates collected from coffee rhizosphere were effective on plant growth promotion. Inoculated plants showed Plant height of 11.71 cm<sup>-1</sup> plant and un-inoculated plant recorded plant height of 8.87 cm-1 plant. Plant growth promoting bacteria inoculation has shown momentous effect on Coffee Arabica growth. Inoculation of PGPR on the Coffee Arabica Plant has shown substantial effect on increasing the growth & growth related parameters (vigor) of Coffee Arabica. Therefore, it is better to check the effect of PGPR isolates inoculation on yield and yield related parameters (Production) of coffee plant by inoculation on controlled and field trial.