BIOCHEMICAL AND MOLECULAR CHARACTERIZATION OF NATIVE Bradyrhizobium STRAINS ISOLATED FROM PIGEON PEA ROOT NODULES OF EASTERN INDIA
DOI:
https://doi.org/10.48165/abr.2025.27.01.47Keywords:
Bioinoculants, Bradyrhizobium, Eastern India, PGPR, pigeon peaAbstract
Pigeon pea (Cajanus cajan) is a major legume crop in Eastern India, contributing significantly to nutritional security and soil fertility through symbiotic association with Bradyrhizobium spp. However, the symbiotic efficiency of native strains under local agro-climatic conditions remains inadequately understood. The present study aimed to isolate, characterize, and identify native bacterial isolates from pigeon pea root nodules and to evaluate their symbiotic efficiency and plant growth-promoting traits. A total of fourteen bacterial isolates were obtained, of which twelve were identified as Bradyrhizobium spp., while isolates S5 and S15 were identified as Pseudomonas azotoformans and Paenibacillus amylolyticus, respectively. All Bradyrhizobium isolates tested positive for catalase, oxidase, nitrate reductase, and nitrogenase activities. Isolates S9, S3, S6, S13, and S1 exhibited significantly higher nitrogenase activity compared to other isolates. Plant growth-promoting assays revealed phosphate solubilization, zinc solubilization, and potassium solubilization in ten, eight, and five isolates, respectively. Eleven isolates produced siderophores, and all siderophore-producing isolates synthesized indole-3-acetic acid (IAA). Notably, isolate S6 (Bradyrhizobium yuanmingense) exhibited all evaluated plant growth-promoting rhizobacteria traits along with high nitrogenase activity, identifying it as the most promising isolate. Isolates S3, S1, and S9 also demonstrated strong potential. The findings highlight the importance of efficient native isolates as region-specific bioinoculants for pigeon pea cultivation, reducing dependence on chemical fertilizers and promoting sustainable agricultural practices.
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Bopape, F.L., Beukes, C.W., Katlego, K., Hassen, A.I., Steenkamp, E.T. and Gwata, E.T. (2022). Symbiotic performance and characterization of pigeon pea (Cajanus cajan L. Millsp.) rhizobia occurring in South African soils. Agriculture, 13(1), 30. https://doi.org/10.3390/agriculture13010030
Chalasani, D., Basu, A., Pullabhotla, S.V.R.N., Jorrin, B., Neal, A.L., Poole, P.S., et al. (2021). Poor competitiveness of Bradyrhizobium in pigeon pea root colonization in Indian soils. mBio, 12, e00423-21. https://doi.org/10.1128/mBio.00423-21
Coico, R. (2006). Gram staining. Current Protocols in Microbiology, 1, A-3C. https://doi.org/10.1002/9780471729259.mca03cs00
Datta, C. and Basu, P.S. (2000). Indole acetic acid production by a Rhizobium species from root nodules of a leguminous shrub, Cajanus cajan. Microbiological Research, 155(2), 123–127.
Degefu, T., Wolde-Meskel, E., Adem, M., Fikre, A., Amede, T. and Ojiewo, C.O. (2018). Morpho-physiological diversity of rhizobia nodulating pigeon pea (Cajanus cajan L. Millsp.) growing in Ethiopia. African Journal of Biotechnology, 17(6), 167–177.
Egamberdieva, D., Berg, G., Lindstrom, K. and Rasanen, L. (2010). Root colonizing Pseudomonas spp. improve growth and symbiosis performance of fodder galega (Galega orientalis Lam.) grown in potting soil. European Journal of Soil Biology, 46(3–4), 269–272.
Flores-Félix, J.D., Sánchez-Juanes, F., Araujo, J., Díaz-Alcántara, C.A., Velázquez, E. and González-Andrés, F. (2023). Two novel symbiovars of Bradyrhizobium yuanmingense (americaense and caribense), the symbiovar tropici of Bradyrhizobium pachyrhizi and the symbiovar cajani of Bradyrhizobium cajani as microsymbionts of Cajanus cajan in the Dominican Republic. Systematic and Applied Microbiology, 46(5), 126454. https://doi.org/10.1016/j.syapm.2023.126454
Fossou, R.K., Pothier, J.F., Zézé, A. and Perret, X. (2020). Bradyrhizobium ivorense sp. nov. as a potential local bioinoculant for Cajanus cajan cultures in Côte d'Ivoire. International Journal of Systematic and Evolutionary Microbiology, 70, 1421–1430.
Ghosh, P.K., Saha, P., Mayilraj, S. and Maiti, T.K. (2013). Role of IAA metabolizing enzymes on production of IAA in root and nodule of Cajanus cajan and its PGP Rhizobium sp. Biocatalysis and Agricultural Biotechnology, 2(3), 234–239.
Gordon, S.A. and Paleg, L.G. (1957). Observations on the quantitative determination of indole acetic acid. Physiologia Plantarum, 10, 39–47.
Granek, J.A. and Magwene, P.M. (2010). Environmental and genetic determinants of colony morphology in yeast. PLoS Genetics, 6(1), e1000823. https://doi.org/10.1371/journal.pgen.1000823
Hall, T.A. (1999). BioEdit: Biological sequence alignment editor and analysis program for Windows 95/98/NT. Nucleic Acids Symposium Series, 41, 95–98.
Jasim, B., Jimtha, C.J., Jyothis, M. and Radhakrishnan, E.K. (2013). Plant growth promoting potential of endophytic bacteria isolated from Piper nigrum. Plant Growth Regulation, 71(1), 1–11.
Jorrin, B., Maluk, M., Atoliya, N., Kumar, S.C., Chalasani, D., Tkacz, A., et al. (2021). Genomic diversity of pigeon pea (Cajanus cajan L. Millsp.) endosymbionts in India and selection of potential strains for use as agricultural inoculants. Frontiers in Plant Science, 12, 680981. https://doi.org/10.3389/fpls.2021.680981
Kumar, S., Singh, P., Kumar, S.C., Prakash, N.R., Banjare, U., Patel, A.K., et al. (2023). Genetic diversity assessment and selection of Bradyrhizobium strains for Inceptisols based on symbiotic performance. Indian Journal of Agricultural Sciences, 93(10), 1126–1131.
Lane, D. (1991). 16S/23S rRNA sequencing. In: Nucleic Acid Techniques in Bacterial Systematics, p. 115. Wiley, Chichester, UK.
Liu, D., Lian, B. and Dong, H. (2012). Isolation of Paenibacillus sp. and assessment of its potential for enhancing mineral weathering. Geomicrobiology Journal, 29(5), 413–421.
Mhango, W.G., Snapp, S. and Kanyama-Phiri, G.Y. (2017). Biological nitrogen fixation and yield of pigeon pea and groundnut: Quantifying response on smallholder farms in northern Malawi. African Journal of Agricultural Research, 12, 1385–1394.
Panek, H.R. and O’Brian, M.R. (2004). KatG is the primary detoxifier of hydrogen peroxide produced by aerobic metabolism in Bradyrhizobium japonicum. Journal of Bacteriology, 186(23), 7874–7880.
Parmar, P. and Sindhu, S.S. (2013). Potassium solubilization by rhizosphere bacteria: Influence of nutritional and environmental conditions. Journal of Microbiology Research, 3, 25–31.
Puppo, A., Pauly, N., Boscari, A., Mandon, K. and Brouquisse, R. (2013). Hydrogen peroxide and nitric oxide: Key regulators of the legume–Rhizobium and mycorrhizal symbioses. Antioxidants and Redox Signaling, 18(16), 2202–2219.
Rai, M.K., Tiwari, V.V., Irinyi, L. and Kövics, G.J. (2014). Advances in taxonomy of genus Phoma: Polyphyletic nature and role of phenotypic traits and molecular systematics. Indian Journal of Microbiology, 54(2), 123–128.
Ramesh, A., Sharma, S.K., Sharma, M.P., Yadav, N. and Joshi, O.P. (2014). Inoculation of zinc solubilizing Bacillus aryabhattai strains for improved growth, mobilization and biofortification of zinc in soybean and wheat cultivated in Vertisols of central India. Applied Soil Ecology, 73, 87–96.
Saravanan, V.S., Madhaiyan, M. and Thangaraju, M. (2007). Solubilization of zinc compounds by the diazotrophic, plant growth promoting bacterium Gluconacetobacter diazotrophicus. Chemosphere, 66(9), 1794–1798.
Schwyn, B. and Neilands, J.B. (1987). Universal chemical assay for the detection and determination of siderophores. Analytical Biochemistry, 160, 47–56.
Sindhu, S.S., Dua, S., Verma, M.K. and Khandelwal, A. (2010). Growth promotion of legumes by inoculation of rhizosphere bacteria. In: Khan, M.S., Zaidi, A. and Musarrat, J. (eds.), Microbes for Legume Improvement, pp. 95–235. Springer, New York, USA.
Stewart, W.D., Fitzgerald, G.P. and Burris, R.H. (1968). Acetylene reduction by nitrogen-fixing blue-green algae. Archiv für Mikrobiologie, 62(4), 336–348.
Upadhyay, S.P., Pareek, N. and Mishra, G. (2015). Isolation and biochemical characterization of Rhizobium strains from nodules of lentil and pea in Tarai agro-ecosystem, Pantnagar, India. Journal National, 7(2), 73–76.
Van Rossum, D., Muyotcha, A., van Verseveld, H.W., Stouthamer, A.H. and Boogerd, F.C. (1994). Siderophore production by Bradyrhizobium spp. strains nodulating groundnut. Plant and Soil, 163(2), 177–187.
Vazquez, P., Holguin, G., Puente, M., Lopez-Cortes, A. and Bashan, Y. (2000). Phosphate solubilizing microorganisms associated with the rhizosphere of mangroves in a semi-arid coastal lagoon. Biology and Fertility of Soils, 30, 460–468.
Verma, M., Singh, A., Dwivedi, D.H. and Arora, N.K. (2020). Zinc and phosphate solubilizing Rhizobium radiobacter (LB2) for enhancing quality and yield of loose leaf lettuce in saline soil. Environmental Sustainability, 3, 209–218.
Walpola, B.C. and Yoon, M.H. (2013). Phosphate solubilizing bacteria: Assessment of their effect on growth promotion and phosphorus uptake of mung bean (Vigna radiata). Chilean Journal of Agricultural Research, 73(3), 275–281.
Wright, M.H., Adelskov, J. and Greene, A.C. (2017). Bacterial DNA extraction using individual enzymes and phenol/chloroform separation. Journal of Microbiology and Biology Education, 18(2), 1110–1128.
Zaidi, A., Khan, M.S., Ahemad, M., Oves, M. and Wani, P.A. (2009). Recent advances in plant growth promotion by phosphate-solubilizing microbes. In: Microbial Strategies for Crop Improvement, pp. 23–50. Springer, Berlin, Germany.
