Screening of phosphate solubilizing bacteria from sugarcane plant rhizosphere as biofertilizer agent for sorghum growth (Sorghum bicolor)

Abstract

Abstract. Prisillia RMA, Susilowati A, Solichatun. 2021. Screening of phosphate solubilizing bacteria from sugarcane plant rhizosphere as biofertilizer agent for sorghum growth (Sorghum bicolor). Asian J Trop Biotechnol 18: 37-45. Sorghum plants (Sorghum bicolor L.) development in Indonesia is still behind due to limited application in a few locations. Sorghum is a crop that can be grown on marginal terrain. The scarcity of nutrients in marginal land necessitates the addition of nutrients. Biofertilizer is a biological fertilizer that comprises microorganisms that act as nutrient suppliers and promote plant growth in the soil. This research included soil sampling, prospective testing, and screening to identify a biofertilizer solubilizing bacterium candidate. Bacterial screening entails bacterial identification, bacterial growth measurement, and a media pH test. The biofertilizer application experiment used a completely randomized design (CRD) with two factors: the first component was the addition of phosphate solubilizing bacteria, which was divided into two levels, without bacteria, and with bacteria. The second factor was variations in the NPK (Nitrogen, Phosphorus, Potassium) fertilizer concentrations of 0, 25, 50, and 100%, which correspond to 0; 0.625; 1.25, and 2.5 g NPK / plant, respectively. The vegetative phase of sorghum growth was observed for 50 days, and height, the number of leaves, leaves color, root length, fresh weight, and dry weight of sorghum plants were determined using ANOVA and DMRT test levels of 5%. Seven isolates of phosphate solubilizing bacteria were obtained from this research. Two possibly superior isolates were produced as biofertilizers: BPF 5 and 12 I. Compared to control treatments, adding BPF 5 and 12 I isolate in combination with varied NPK fertilizer concentrations significantly altered sorghum growth parameters, such as plant height, root length, fresh weight, and dry weight. The addition of BPF 12 I isolates at 0% and 25% fertilizer concentrations results in sorghum growth.