The Application of Phosphate Solubilizing Microbes Biofertilizer to Increase Soil P and Yield of Maize on Ultisols Jatinangor

Abstract

Ultisols has problems of low availability of nutrients, especially phosphorus. To improve soil phosphate and P fertilizer efficiency, it is necessary to develop biofertilizer such as phosphate solubilizing microbes. Phosphate solubilizing microbes (PSM) have the capability of dissolving soil phosphorus which have been adsorbed and can mineralize organic P to become inorganic P, hence increasing the avalibility of P in the soil. Phosphate solubilizing bacteria (Pseudomonas mallei and Pseudomonas cepacea) and phosphate solubilizing fungi (Penicillium sp. and Aspergillus sp) were selected based on their ability to dissolve P. The experiment was conducted at Jatinangor, West Java Indonesia to study the application of PSM biofertilizer to increase soil P and yield of maize. Experiment used a Randomized Block Design (RBD) in factorial pattern, consisting of two factors with three replications. The first factor consisted of PSM biofertilizer, which were; without PSM, 5 L ha-1 of PSM and 50 kg ha-1 of PSM.  The second factor was P fertilizer with five levels (0%, 25%, 50%, 75% and 100% dosage of recommendation). The results showed that the application of PSM biofertilizer increased soil phosphate and yield of maize on Ultisol Jatinangor.  The dosage of P inorganic fertilizers was reduced by 50%.Keywords: ultisol, maize, biofertillizer, phospate-solubilizing bacteria.