keywords: Biofertilizers, bacteria, chemical fertilizers, germination, microorganisms, soil
Biofertilizer is an environmental friendly alternative to chemical fertilizers to increase soil fertility. It is also used in crop production in sustainable farming, because the long term use of chemical fertilizers destroy the friability of the soil. Soil samples were collected from different agricultural farms in Ibadan Oyo State. The samples were collected with clean ziplock polythene bags and transported to the laboratory on ice pack. Total bacteria counts, plant growth promoting abilities of the isolates such as nitrogen fixation, phosphate and potassium solubilization were determined using nutrient agar, glucose nitrogen free media, Pikovskaya and Aleksandrouv media, respectively. The highest total bacteria count on nutrient agar was recorded for sample H (16.8) (Nihort farm) whereas the lowest count was recorded for sample C (6.90) (Southern farm). The isolated organisms used for the inoculation were Micrococcus sp, Pseudomonas sp, P. fluorescence, Bacillus sp, Alcaligens sp and Proteus sp. It has been observed that the isolates have the ability to fix nitrogen, solubilize phosphate and potassium. It was also observed that the control had the lowest percentage germination. In conclusion, it was observed that the isolates were capable of improving the plant growth in terms of leaf length, root length and percentage germination.