Isolation and Characterization of Enhanced Phosphate Solubilization Bacteria from Rhizosphere Soil of Litchi chinensis
TL;DR
The results suggest that these PSB strains could be useful for sustainable agricultural practices, as they can improve soil phosphorus availability and soil fertility.
Abstract
Phosphorus is a vital nutrient that plants need to grow and develop, and its availability is limited because it is continuously fixed with metallic compounds, which form insoluble complexes. To address this problem, chemical phosphorus fertilizers have been used extensively. However, prolonged use of these fertilizers has several disadvantages, including causing nutrient imbalances, degrading soil fertility by disrupting beneficial microbes, and leading to soil acidification. To find a sustainable solution research has explored naturally occurring phosphate-solubilizing bacteria (PSBs). The purpose of the current research was to isolate and screen PSB’s from rhizospheric soil of Litchi. Total 30 bacterial isolates were tested for phosphate solubilization using a halo-zone method. Six of these bacterial isolates exhibited significant phosphate solubilizing activity, with a Phosphate Solubilization Index (PSI) of ≥2. All six isolates were further analyzed to quantify the released phosphate. These bacterial isolates demonstrated remarkable efficiency in solubilizing insoluble tricalcium phosphate, with soluble phosphorus levels ranging from 288.44-723.42 µg ml-1. Biochemical tests and molecular characterization were conducted to identify six bacterial isolates, which were identified as Priestia megaterium, Bacillus sp., Shouchella clausii, and Pseudomonas sp. The results suggest that these PSB strains could be useful for sustainable agricultural practices, as they can improve soil phosphorus availability and soil fertility.