Mahendra Singh


The objective of the present study was to isolate and characterize most efficient phosphate solubilizing bacteria (PSB) from rice rhizosphere. The study was carried out during the Kharif season’2018 at Department of Soil Science and Agricultural Chemistry, Bihar Agricultural University, Sabour, Bhagalpur, Bihar. The availability of phosphorous to plants for uptake and utilization is limited in soil due to fixation in the form of Fe-P, Al-P and Ca-P. The use of phosphate solubilizing bacteria can prove to be helpful measure to supply phosphorous to the crops to increase the productivity. In the present investigation, a total of 10 isolates were obtained from rice rhizosphere soil samples. All ten isolated isolates were shown phosphorus solubilization. Out of ten isolates BAU3 was found to be most potent phosphate solubilizers showing clear halo zone around its colony. The isolate BAU3 showed 20.00 mm phosphate solubilizing halo zone around its colony. The solubilization index (SI) of the isolate BAU3 was also calculated at the end of the incubation period and observed phosphate solubilization index (SI) of 3.22.  The isolate BAU3 showed maximum insoluble phosphate solubilization of 450.24 ?g ml-1 and isolates BAU3 was selected for subsequent studies. The bacterial isolates BAU3 was gram negative, non-spore forming rods shaped. On the basis of the 16SrDNA sequencing, isolate BAU3 was identified as Enterobacter cloacae strain BAU3 (Genebank Accession No.   MK033472). The isolated strain of bacterial has potential to solubilize insoluble phosphorus and it can be utilized for preparation of microbial inoculants or biofertilizers.


Download data is not yet available.




E. cloacae BAU3, Phosphate solubilizing bacteria, Rice, Solubilization index

Ahemad, M. and Khan, M.S. (2010). Plant growth promoting activities of phosphate-solubilizing Enterobacter asburiae as influenced by fungicides, Eur. Asia J. Bio. Sci., 4: 88-95
Banerjee S., Palit, R., Sengupta C. and Standing, D. (2010). Stress-induced phosphate solubilization by Arthrobacter sp. and Bacillus sp. isolated from tomato rhizosphere, Aust. J. Crop Sci,. 4: 378-383.
Belal, E.B., Hassan, M.M. and El-Ramady, H.R. (2013) Phylogenetic and characterization of salt-tolerant rhizobial strain nodulatingfaba bean plants. Afr. J. Biotechnol, 12 (27), 4324-4337.
Borham, A., Blal, M., Metwaly and Gremy, S. El. (2017). Phosphate Solubilization by Enterobacter cloacae and its Impact on Growth and Yield of Wheat Plants, J. Sus. Agric .Sci. 43(2): 89 -103.
Braum, S. M. and Helmke, P. A. (1995). White lupin utilizes soil phosphorus that is unavailable to soybean. Plant Soil, 176:95-100.
Buchanan, R.E. and Gibbons, N. E. (1974): Bergey’s Manual of Determinative Bactriology, 8th ed. Baltimore: Williams & Wilkins Co.
Chung, H., Park, M., Madhaiyan, M., Seshadri, S., Song, J., Cho, H. and Sa, T. (2005) Isolation and characterization of phosphate solubilizing bacteria from the rhizosphere of crop plants of Korea. Soil Biol. Biochem., 37, 1970-1974.
Coutinho, F.P., Felix, W.P. and Yano-Melo, A.M. (2012) Solubilization of phosphates in vitro by Aspergillus spp. and Penicillium spp. Ecol. Eng. 42, 85-89.
Gulati A, Sharma N, Vyas P, Sood S, Rahi P, Pathania V. and Prasad, R. (2010) Organic acid production and plant growth promotion as a function of phosphate solubilization by Acinetobacter rhizosphaerae strain BIHB 723 isolated from the cold deserts of the trans-Himalayas. Arch Microbiol, 192:975-983
Kannapiran, E. and Ramkumar, V. (2011). Isolation of phosphate solubilizing bacteria from the sediments of Thondi coast, Palk Strait, Southeast coast of India. Annals Bio. Res. 2: 157-163.
Kumar, T., Kumar, V. and Anshumali. (2012). Phosphate Solubilizing Activity of Some Bacterial Strains Isolated from Chemical Pesticide Exposed Agriculture Soil. Inter. J. Engg. Res. Dev; 3: 01-06.
Kundu, B. S., Nehra, K., Yadav, R. and Tomar, M. (2009). Biodiversity of phosphate solubilizing bacteria in rhizosphere of chickpea, mustard and wheat grown in different regions of Haryana. Ind. J. Microbiol; 49:120–127.
Leandro, M. M., Oliveira, S. M., Soares, C. R. F. S. and Moreira, F. M. S. (2011). Solubilisation of Inorganic Phosphates by Inoculant Strains From Tropical Legumes. J. Agric. Sciences., 68:603-609.
Mirza B S, Welsh A, Rasul G, Rieder, J.P., Paschke M.W. and Hahn, D. (2009) Variation in Frankia populations of the Elaeagnus host infection group in nodules of six host plant species after inoculation with soil. Microbial Ecol. 58:384-393
Nagar, N.R., Amaresan, N., Patel, A. and Bhargava, P. (2017). Gujarat Biodiversity Gene Bank, Gujarat State Biotechnology Mission, 9th floor, 11th Block, Udyogbhavan, Gandhinagar, Gujarat 382010, India
Panhwar, Q.A., Radziah, O., Zaharah, A.R., Sariah, M. and Razi, I.M. (2011) Role of phosphate solubilizing bacteria on rock phosphate solubility and growth of aerobic rice. J. Environ. Biol., 32, 607-612.
Paul, D. and Sinha, S.N. (2013). Isolation of phosphate solubilizing bacteria and total heterotrophic bacteria from river water and study of phosphatase activity of phosphate solubilizing bacteria, Adv. Appl. Sci. Res. 4: 409-412.
Pikovskaya, R.I. (1948). Mobilization of phosphorus in soil in connection with vital activity of some microbial species. Microbiologiya, 17: 362–370
Premono, M. E., Moawad A.M., P Vleck.L.G. (1996). Effect of phosphate solubilizing Pseudomonas putida on the growth of maize and its survival in the rhizosphere, Indones. J. Crop Sci. 11: 13-23.
Saber, K., Nahla, L.D. and Chedly, A. (2005) Effect of P on nodule formation and N fixation in bean. Agron Sustain Develop., 25, 389-393. doi: 10.1051/ agro:2005034
Subba, R.N.S. (1993). Biofertilizeres in Agriculture and Forestry, 3rd ed., Oxford and IBH Publishing Co. Pvt. LTD., New Delhi. pp.129-135.
Tamura K., Peterson D., Peterson N., Stecher G., Nei M., and Kumar S. (2013a). MEGA5: Molecular Evolutionary Genetics Analysis using Maximum Likelihood, Evolutionary Distance, and Maximum Parsimony Methods. Molecular Biology and Evolution 28: 2731-2739.
Tamura K., Stecher G., Peterson D., Filipski A. and Kumar S. (2013b). MEGA6: molecular evolutionary genetics analysis version 6.0, Mol. Biol. Evol. 30: 2725-2729.
Thakur, I.B. and Putatunda, C. (2017). In vitro Phosphate Solubilization by Enterobacter spp. Isolated from Wheat Rhizosphere, J Pure and Applied Microbiology; 11(4): 2007-2015.
Thompson, J.D., Gibson, T.J., Plewniak, F., Jeanmougin, F. and Higgins, D.G. (1997). The CLUSTAL_X windows interface: flexible strategies for multiple sequence alignment aided by quality analysis tools. Nucleic Acids Res. 25:4876-4882
Vazquez, P., Holguin, G., Puente, M. E., Lopez, C. A., Bashan, J. (2000). Phosphate-solubilizing microorganisms associated with the rhizosphere of mangroves in a semiarid coastal lagoon. Bio. Fert. Soils. 30: 460–468.
Xiao, C.Q., Chi, R.A., Li, X.H., Xia, M. and Xia, Z.W. (2011). Biosolubilization of rock phosphate by three stress-tolerant fungal strains. Appl. Biochem. Biotechnol., 165, 719-727.
Yadav, J., Verma, J.P., Yadav, S.K. and Tiwari, K.N. (2010). Effect of salt concentration and pH on soil inhabiting fungus Penicillium citrinum Thom for solubilization of Tricalcium phosphate. Microbial. J. 1:1-7
Zhang Z., Schwartz S., Wagner L. and Mille, W. (2000). A greedy algorithm for aligning DNA sequences, J. Comput. Biol. 7: 203-214.
Citation Format
How to Cite
Singh, M. (2018). Isolation and characterization of insoluble inorganic phosphate solubilizer rice rhizosphere strain Enterobacter cloacae BAU3. Journal of Applied and Natural Science, 10(4), 1204-1209. https://doi.org/10.31018/jans.v10i4.1929
More Citation Formats:
Research Articles

Most read articles by the same author(s)