Isolation and Molecular Identification of Phosphate Solubilizing Bacteria, Bacillus licheniformis UBPSB-07 Capable of Enhancing Seed Germination in Vigna radiata L.

摘要

In the present study, the growth enhancement properties of phosphate-solubilizing bacteria (PSB) isolated from the agricultural soils, Cochin, Kerala, India was investigated. Among seventeen bacterial isolates, UBPSB-07 was found to be an efficient phosphate solubiliser. The bacterial isolate was identified by phenotype and 16S rDNA sequencing as Bacillus licheniformis. The isolate UBPSB-07 increased bioavailability of soil phosphorus which resulted in increased growth of the experimental plant, Vigna radiata L. The isolate showed the highest solubilization index in 72 hours on PKV agar and phosphatase activity of 0.4 U/ml/min at a temperature of 45°C and at pH 7. The bacterial isolate was found to produce the plant growth hormone, indole-3-aceticacid (IAA) as detected by TLC and colorimetric methods. Growth experiments on Vigna radiata L. showed that the isolate has a significant effect on increasing root length and overall growth of seedlings. Based on these studies, it is concluded that the isolated phosphate solubilizing bacteria are likely to serve as an efficient biofertilizer and strong plant growth promoter to increase the overall performance of crops.