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Research Articles

Vol. 13 No. sp6 (2026): National Conference on “Harnessing Genetic Resources for Food Security: Innovations in Conservation and Utilization for Sustainable Crop Improvement in Northeast Region”

Uncovering the microbial diversity of Chak-hao rice: Isolation and characterisation of indigenous beneficial microbes in Manipur

DOI
https://doi.org/10.14719/pst.14335
Submitted
3 March 2026
Published
18-08-2026

Abstract

Chak-hao (Oryza sativa L.), an aromatic black glutinous rice native to Manipur, is valued for its unique fragrance and high nutraceutical value, including iron, vitamin E and antioxidants. The present study aimed to isolate and characterise beneficial rhizospheric and endophytic microbes that could enhance Chak-hao rice cultivation. A total of 170 bacterial and 55 fungal isolates were obtained from different Chak-hao varieties collected from the farmers’ fields across four districts of Manipur. These isolates were screened for plant growth-promoting traits such as phosphate solubilisation, indole-3-acetic acid (IAA) production, nitrogen fixation and antagonistic activity against harmful fungal pathogens. The study showed 51.94 % phosphate solubilisation, 41.26 % produced IAA and 9.2 % exhibited nitrogen-fixing ability. Based on multiple plant growth promoting traits, 11 promising isolates were selected for molecular characterisation. The 16S ribosomal DNA (16S rDNA) sequencing identified these isolates as belonging to Bacillus, Enterobacter and Pseudomonas genera, with Bacillus species being predominant. Microbial inoculation significantly improved grain yield, straw yield and aroma-associated compounds compared to the untreated control (p ≤ 0.05, Duncan’s multiple range test). The study reveals the potential of indigenous beneficial microbes as eco-friendly biofertilisers and biocontrol agents for sustainable Chak-hao rice cultivation, quality grain improvement and conservation of unique Chak-hao rice germplasm Manipur.

References

  1. 1. Sarika K, Singh SG, Chanu TR, Lanah S, Meetei CC, Pyngrope AH, et al. An insight into the morphological, biochemical and molecular diversity of GI tagged black scented rice, Chak-hao landraces of Manipur, India. Plant Genet Resour. 2025;1–11. https://doi.org/10.1017/S1479262125100270
  2. 2. Chanu CS, Yenagi NB. Nutritional and antioxidant profile of black rice-based (Poireiton Chak-hao and Chak-hao Amubi) traditional foods of Manipur. J Appl Nat Sci. 2025;17(2). https://doi.org/10.31018/jans.v17i2.6254
  3. 3. Pratiwi R, Purwestri YA. Black rice as a functional food in Indonesia. Funct Foods Health Dis. 2017;7(3):182–94. https://doi.org/10.31989/ffhd.v7i3.310
  4. 4. Kong Z, Liu H. Modification of rhizosphere microbial communities: A possible mechanism of plant growth-promoting rhizobacteria enhancing plant growth and fitness. Front Plant Sci. 2022;13:920813. https://doi.org/10.3389/fpls.2022.920813
  5. 5. Khanina O, Hladchenko A, Lavrentii D, Kuzmenko H, Kruhlov V, Kryzyna O. Mechanisms of state management of personnel development of the health care system. Econ Aff. 2024;69:187–95. https://doi.org/10.46852/0424-2513.1.2024.21
  6. 6. Volpiano CG, Lisboa BB, São José JF, Beneduzi A, Granada CE, Vargas LK. Soil-plant-microbiota interactions to enhance plant growth. Rev Bras Cienc Solo. 2022;46:e0210098. https://doi.org/10.36783/18069657rbcs20210098
  7. 7. Pieterse CMJ, Zamioudis C, Berendsen RL, Weller DM, Van Wees SCM, Bakker PAHM. Induced systemic resistance by beneficial microbes. Annu Rev Phytopathol. 2014;52(1):347–75. https://doi.org/10.1146/annurev-phyto-082712-102340
  8. 8. Dlamini SP, Akanmu AO, Babalola OO. Rhizospheric microorganisms: The gateway to a sustainable plant health. Front Sustain Food Syst. 2022;6:925802. https://doi.org/10.3389/fsufs.2022.925802
  9. 9. Vandana P, Kumari A, Kumari K, Puzari KR. Endophytes: An insight into plant's hidden treasure. Int J Plant Soil Sci. 2024;36(7):589–609. https://doi.org/10.9734/ijpss/2024/v36i74770
  10. 10. Rhouma A, Rhouma R, Hajji-Hedfi L. Unveiling the bioactive potential of endophytic fungi. Nova Hedwigia. 2025;109–38. https://doi.org/10.1127/nova_hedwigia/2025/0996
  11. 11. Akram S, Ahmed A, He P, He P, Liu Y, Wu Y, et al. Uniting the role of endophytic fungi against plant pathogens and their interaction. J Fungi. 2023;9(1):72. https://doi.org/10.3390/jof9010072
  12. 12. Rabbee MF, Ali MS, Islam MN, Rahman MM, Hasan MM, Baek KH. Endophyte mediated biocontrol mechanisms of phytopathogens in agriculture. Res Microbiol. 2024;175:104229. https://doi.org/10.1016/j.resmic.2024.104229
  13. 13. Nayak S, Samanta S, Sengupta C, Swain SS. Rice crop loss due to major pathogens and the potential of endophytic microbes for their control and management. J Appl Biol Biotechnol. 2021;9(5):166–75. https://doi.org/10.7324/JABB.2021.9523
  14. 14. Cai N, Wang F, Nong X, Wang G, McNeill M, Cao G, et al. Visualising confirmation of the endophytic relationship of Metarhizium anisopliae with maize roots using molecular tools and fluorescent labelling. Biocontrol Sci Technol. 2019;29(11):1023–36. https://doi.org/10.1080/09583157.2019.1641792
  15. 15. Sandhu SS, Mahal SS, Kaur A. Physicochemical, cooking quality and productivity of rice as influenced by planting methods, planting density and nitrogen management. Int J Food Agric Vet Sci. 2015;5(1):33–40.
  16. 16. Breidenbach B, Pump J, Dumont MG. Microbial community structure in the rhizosphere of rice plants. Front Microbiol. 2016;6:1537. https://doi.org/10.3389/fmicb.2015.01537
  17. 17. Ding LJ, Cui HL, Nie SA, Long XE, Duan GL, Zhu YG. Microbiomes inhabiting rice roots and rhizosphere. FEMS Microbiol Ecol. 2019;95(5):fiz040. https://doi.org/10.1093/femsec/fiz040
  18. 18. Bhattacharyya C, Imchen M, Mukherjee T, Haldar S, Mondal S, Mukherji S, et al. Rhizosphere impacts bacterial community structure in the tea (Camellia sinensis (L.) O. Kuntze) estates of Darjeeling, India. Environ Microbiol. 2022;24(6):2716–31. https://doi.org/10.1111/1462-2920.15874
  19. 19. Deshmukh Y, Khare P, Patra D. Rhizobacteria elevate principal basmati aroma compound accumulation in rice variety. Rhizosphere. 2016;1:53–7. https://doi.org/10.1016/j.rhisph.2016.07.001
  20. 20. Maghboli Balasjin N, Maki JS, Schläppi MR, Marshall CW. Plant growth-promoting activity of bacteria isolated from Asian rice (Oryza sativa L.) depends on rice genotype. Microbiol Spectr. 2022;10(4):e02787–21. https://doi.org/10.1128/spectrum.02787-21
  21. 21. Takamoto A, Takahashi T, Togami K. Estimation models from soil pH with a solid-to-liquid ratio of 1:2.5 to pH measured by other methods using soils in Japan. Soil Sci Plant Nutr. 2023;69(3):190–8. https://doi.org/10.1080/00380768.2023.2190749
  22. 22. Sahu PK, Tilgam J, Mishra S, Hamid S, Gupta A, K J, et al. Surface sterilization for isolation of endophytes: Ensuring what (not) to grow. J Basic Microbiol. 2022;62(6):647–68. https://doi.org/10.1002/jobm.202100462
  23. 23. Babana AH, Dicko AH, Maïga K, Traoré D. Characterization of rock phosphate-solubilizing microorganisms isolated from wheat (Triticum aestivum L.) rhizosphere in Mali. J Microbiol Microb Res. 2013;1(1):1–6.
  24. 24. Nautiyal CS, Bhadauria S, Kumar P, Lal H, Mondal R, Verma D. Stress induced phosphate solubilization in bacteria isolated from alkaline soils. FEMS Microbiol Lett. 2000;182(2):291–6. https://doi.org/10.1111/j.1574-6968.2000.tb08910.x
  25. 25. Susilowati DN, Riyanti EI, Setyowati M, Mulya K. Indole-3-acetic acid producing bacteria and its application on the growth of rice. In: AIP Conference Proceedings. 2018;2002(1):020016. https://doi.org/10.1063/1.5050112
  26. 26. Baldani JI, Reis VM, Videira SS, Boddey LH, Baldani VLD. The art of isolating nitrogen-fixing bacteria from non-leguminous plants using N-free semi-solid media: A practical guide for microbiologists. Plant Soil. 2014;384(1–2):413–31. https://doi.org/10.1007/s11104-014-2186-6
  27. 27. Cordova-Rodriguez A, Rentería-Martínez ME, López-Miranda CA, Guzmán-Ortíz JM, Moreno-Salazar SF. Simple and sensitive spectrophotometric method for estimating the nitrogen-fixing capacity of bacterial cultures. MethodsX. 2022;9:101917. https://doi.org/10.1016/j.mex.2022.101917
  28. 28. Sultana S, Shaheen K, Nongthombam A, Shingmuan H, Chanu WP, Khunjamayum R, et al. Antifungal trait and plant growth promotion potential of Bacillus spp. from rhizosphere soils of black aromatic rice, ‘Chakhao’. Curr Agric Res J. 2023;11(2). https://doi.org/10.12944/CARJ.11.2.07
  29. 29. Devi WJ, Vivekananda Y, Uddin A, Laishram JM, Chakraborty S. Morpho-agronomic characterization and evaluation of a gene based marker in three aromatic pigmented Chakhao rice accessions of Manipur. ORYZA. 2020;57(2):100–7. https://doi.org/10.35709/ory.2020.57.2.3
  30. 30. Kumar V, Jain L, Jain SK, Chaturvedi S, Kaushal P. Bacterial endophytes of rice (Oryza sativa L.) and their potential for plant growth promotion and antagonistic activities. S Afr J Bot. 2020;134:50–63. https://doi.org/10.1016/j.sajb.2020.02.017
  31. 31. Wan W, Tan J, Wang Y, Qin Y, He H, Wu H, et al. Responses of the rhizosphere bacterial community in acidic crop soil to pH: Changes in diversity, composition, interaction and function. Sci Total Environ. 2020;700:134418.
  32. 32. Edwards J, Johnson C, Santos-Medellín C, Lurie E, Podishetty NK, Bhatnagar S, et al. Structure, variation and assembly of the root-associated microbiomes of rice. Proc Natl Acad Sci U S A. 2015;112(8):E911–E920. https://doi.org/10.1073/pnas.1414592112
  33. 33. Lundberg DS, Lebeis SL, Paredes SH, Yourstone S, Gehring J, Malfatti S, et al. Defining the core Arabidopsis thaliana root microbiome. Nature. 2012;488(7409):86–90. https://doi.org/10.1038/nature11237
  34. 34. Jena R, Mukherjee AK, Swain H, Samanta S, Adak T. Isolation of endophytic fungi from wild rice species for disease management and growth promotion in cultivated rice (Oryza sativa L.). Biocontrol Sci Technol. 2024;34(5):411–37. https://doi.org/10.1080/09583157.2024.2351812
  35. 35. Borah M, Das S, Bora SS, Boro RC, Barooah M. Comparative assessment of multi-trait plant growth-promoting endophytes associated with cultivated and wild Oryza germplasm of Assam, India. Arch Microbiol. 2021;203(5):2007–28. https://doi.org/10.1007/s00203-020-02153-x
  36. 36. Khaskheli MA, Wu L, Chen G, Chen L, Hussain S, Song D, et al. Isolation and characterization of root-associated bacterial endophytes and their biocontrol potential against major fungal phytopathogens of rice (Oryza sativa L.). Pathogens. 2020;9(3):172. https://doi.org/10.3390/pathogens9030172
  37. 37. Bell DK, Wells HD, Markham CR. In vitro antagonism of Trichoderma species against six fungal plant pathogens. Phytopathology. 1982;72:379–82. https://doi.org/10.1094/Phyto-72-379
  38. 38. Lane DJ. 16S/23S rRNA sequencing. In: Stackebrandt E, Goodfellow M, editors. Nucleic acid techniques in bacterial systematics. New York: John Wiley & Sons; 1991. p. 115–75.
  39. 39. White TJ, Bruns T, Lee SJ, Taylor J. Amplification and direct sequencing of fungal ribosomal RNA genes for phylogenetics. In: Innis MA, Gelfand DH, Sninsky JJ, White TJ, editors. PCR protocols: A guide to methods and applications. San Diego (CA): Academic Press; 1990. p. 315–22. https://doi.org/10.1016/B978-0-12-372180-8.50042-1
  40. 40. Tian Q, Gong Y, Liu S, Ji M, Tang R, Kong D, et al. Endophytic bacterial communities in wild rice (Oryza officinalis) and their plant growth-promoting effects on perennial rice. Front Plant Sci. 2023;14:1184489. https://doi.org/10.3389/fpls.2023.1184489
  41. 41. Kavitha K, Kaviyarasan S, Indra N, Thilagavathi R, Rajinimala N, Preetha G, et al. Induction of fungal disease resistance in rice mediated by bacterial endophytes. Plant Sci Today. 2025;12:4681. https://doi.org/10.14719/pst.4681
  42. 42. Krishnan GV, Abraham B, Lankalapalli RS, Bhaskaran Nair Saraswathy Amma DK, Bhaskaran K. Rice sheath blight disease control by native endophytic Bacillus subtilis from Kuttanad, a Globally Important Agricultural Heritage System. N Z J Bot. 2025;63(4):658–80. https://doi.org/10.1080/0028825X.2024.2394184
  43. 43. Yousefi H, Hassanzadeh N, Behboudi K, Firouzjahi FB. Identification and determination of characteristics of endophytes from rice plants and their role in biocontrol of bacterial blight caused by Xanthomonas oryzae pv. oryzae. Hell Plant Prot J. 2018;11(1):19–33. https://doi.org/10.2478/hppj-2018-0003
  44. 44. Cheng T, Yao XZ, Wu CY, Zhang W, He W, Dai CC. Endophytic Bacillus megaterium triggers salicylic acid-dependent resistance and improves the rhizosphere bacterial community to mitigate rice spikelet rot disease. Appl Soil Ecol. 2020;156:103710. https://doi.org/10.1016/j.apsoil.2020.103710
  45. 45. Ooi YS, Nor NM, Furusawa G, Tharek M, Ghazali AH. Application of bacterial endophytes to control bacterial leaf blight disease and promote rice growth. Plant Pathol J. 2022;38(5):490–501. https://doi.org/10.5423/PPJ.OA.01.2022.0014
  46. 46. Sekar K, Kumaresan K, Nallasamy I, Palaniappan M, Kandan T. Isolation and characterization of seed-borne endophytes for antifungal activity and plant growth promotion in rice. J Pure Appl Microbiol. 2024;18(4). https://doi.org/10.22207/JPAM.18.4.54
  47. 47. Khan N, Humm EA, Jayakarunakaran A, Hirsch AM. Reviewing and renewing the use of beneficial root and soil bacteria for plant growth and sustainability in nutrient-poor, arid soils. Front Plant Sci. 2023;14:1147535. https://doi.org/10.3389/fpls.2023.1147535
  48. 48. Dhondge HV, Barvkar VT, Paul D, Dastager SG, Pable AA, Nadaf AB. Exploring the core microbiota in scented rice (Oryza sativa L.) rhizosphere through metagenomics approach. Microbiol Res. 2022;263:127157. https://doi.org/10.1016/j.micres.2022.127157

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