Isolation and characterization of phosphate solubilizing bacteria isolated from tropical upland reforestation soil

Abstract

Microorganisms of solubilizing phosphorus (P) pools in soils are considered essential in promoting P bioavailability. A study was conducted in laboratory to screen and isolate Phosphate solubilizing bacteria (PSB) taken from tropical upland reforestation soil in Sungai Chuchuh UniMAP Campus, Perlis and to evaluate the biodiversity between the sampling from Housing area (HA) and Orchard area (OA). The PSB were isolated from rhizhosphere on nutrient agar (NA) medium by the serial dilutions. Bacterial cells concentration was determined by using colony forming unit (CFU) method. On the other hand, the most efficient phosphate solubilizers were detected on National Botanical Research Institute Phosphorus (NBRIP) selective medium by measuring the clear zone around the bacterial colony. The highest Solubilizing efficiency (SE) activity (123.61 %) was found in PSB 5 (OA) strains grown in NBRIP selective media plate. The results were shown that about twelve (12) PSB strains were isolated and has been characterize as eight (8) gram positive and four (4) gram negative bacteria also has been classified based on their morphological criteria. Isolated PSB strains were capable to produce organic acids since the pH of medium has been reduced. PSB inoculants with their beneficial traits would be considered as potential biofertilizer for the sustainable agricultural systems especially in Tropical Upland Reforestation Soil in Sungai Chuchuh as well as in other places.