Isolation and characterization of phosphate solubilizing rhizobacteria to improve plant health of tomato

• Published in: Plant and soil Vol. 316; no. 1/2; pp. 13 - 24
• Main Authors: Hariprasad, P., Niranjana, S. R.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer 01.03.2009; Springer Netherlands; Springer Nature B.V
• Subjects: Acid soils; Agricultural soils; Agronomy. Soil science and plant productions; Animal, plant and microbial ecology; Bacteria; Biological and medical sciences; Biomedical and Life Sciences; Ecology; Fundamental and applied biological sciences. Psychology; Life Sciences; Organic soils; Phosphates; Phosphorus; Plant biology; Plant diseases; Plant Physiology; Plant Sciences; Plants; Regular Article; Seedlings; Soil biochemistry; Soil microorganisms; Soil samples; Soil Science & Conservation; Solubilization; Tomatoes; Phosphate solubilizing rhizobacteria; Early blight; Phytase; Phosphorous; Fusarium wilt; Organic acid; Soil plant relation; Fusarium wilt . Early blight
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1007/s11104-008-9754-6

In the present study, 43 isolates of Phosphate solubilizing rhizobacteria (PSRB) were isolated from 37 rhizospheric soil samples of tomato collected from tomato growing regions of Karnataka. Among the 43 isolates, 33 were found to be positive for solubilizing both inorganic and organic forms of phosphorous. The isolates were analyzed for their ability to colonize roots of tomato and to increase the seed quality parameters under laboratory conditions. On the basis of above criteria, 16 isolates were selected for further studies. Organic acids from PSRB isolates were analyzed and phytase zymogram for two isolates viz., PSRB21 and 31 was prepared. Under greenhouse conditions, all selected isolates showed increased shoot length, root length, fresh weight, dry weight and phosphorous content of tomato seedlings to various extent with respect to control. Analysis of pH and available phosphorous in rhizosphere soil samples of 30 dayold-seedlings revealed that the available phosphorous content was high in rhizospheric soil samples of plants raised from seeds bacterized with PSRB isolates over control. Even though all selected PSRB's were able to increase the plant growth, only few of them showed protection against fusarium wilt and none of them against early blight.