Indigenous Phosphate Solubilizing Bacteria from Peat Soil for an Eco-friendly Biofertilizer in Oil Palm Plantation
Abstract
Degradation in soil fertility is an enormous problem in agricultural intensification system. Availability in phosphate is one of among encountered problems. Peat soils have large areas and great potential for agriculture and plantations, but have many obstacles in their management. One of the issues is the low soil fertility and low availability of nutrients, especially phosphate which exists in many organic forms that are not available to plants. Phosphorous is an essential element after nitrogen, which plays an important role in plant growth and metabolism and the process of soil microbiology. Introduction of phosphate- solubilizing bacteria (PSB) as biofertilizer, is a renewable energy based which can increase the availability of phosphate to plants can overcome this problem and at the same time reducing the use of inorganic P fertilizer. Indigenous PSB, isolated from palm oil plantation could be used as a better and friendly bio-agent to improve soil fertility, specifically for phosphate availability. Eight PSB have been isolated from peat soil in oil palm platation. Morphological, biochemical characterization and molecular identifications showed that the 8 isolates belonged to Flavobacterium and Enterobacter genera, more precisely the species of Burkholderia sp and Novosphingobium nitrogenifigens. Characterization of isolates of the highest PSB activity consisted of the ability to dissolve phosphate in Pikovskaya solid medium, temperature resistance optimization and the ability to produce phosphatase enzyme. Results showed that isolate with the highest potentiality of dissolving phosphate formed 3.5 cm of clear zone diameter and the phosphatase activity at 9 days of incubation 5.992 units (μmol / ml / min). The peak of enzyme’s activity was reached at 6 days , which corresponded to 54.782 ppm of phosphorus solubilised. The lowest pH (3.2) was reached at 1st day of incubation. These isolates showed the ability to grow optimally at temperature range of 25 to 300C. Indigenous PSB could be used as biofertilizer agents which are eco friendly.
Keywords: indigenous; biofertilizer; renewable energy, phosphate solubilizing bacteria;phosphatase; oil palm
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