Endophytic Bacteria of Mangrove Roots from the West Coast of Lombok Island with Phosphate-Solubilizing and IAA-Producing Abilities as Biofertilizer Candidates
DOI:
10.29303/jbt.v25i4b.11175Published:
2025-12-27Downloads
Abstract
Mangrove ecosystems are unique habitats with extreme environmental conditions that select for adaptive endophytic microorganisms, making them a potential source of plant growth-promoting bacteria (PGPB). Exploring the potential of endophytes as biofertilizers to reduce dependence on chemical fertilizers is crucial in the context of sustainable agriculture. This study aims to characterize the potential of mangrove root endophytic bacteria from the coast of Lombok as biofertilizer agents through the evaluation of Indole-3-Acetic Acid (IAA) hormone production and phosphate solubilization ability. Endophytic bacteria were isolated from roots, evaluated for IAA production using the Salkowski method, while phosphate solubilization ability was evaluated qualitatively on Pikovskaya agar and quantitatively in liquid culture using molybdenum blue spectrophotometry. Potential isolates were characterized morphologically to determine their bacterial genus. The results showed that all isolates produced IAA, with AV1 (51.52 ppm) and AV4 (42.86 ppm) categorized as high producers. Phosphate solubilization ability varied significantly, with AV1 showing the strongest activity (index 4.41), followed by M1 (1.93), while some isolates showed low to no activity. Quantitative tests showed a peak in dissolved phosphate on day 4, with M2 (18.20 ppm) and M1 (16.31 ppm) being the most efficient phosphate solubilizers. Phenotypic characterization identified all promising isolates (AV1, AV4, M1) as Gram-positive, rod-shaped bacteria belonging to the genus Bacillus sp. based on Bergey’s Manual of Systematic Bacteriology. Overall, AV1, AV4, and M1 were identified as the most promising candidates for further development as biofertilizers.
Keywords:
Mangrove endophytes; phosphate solubilization; Indole-3-Acetic Acid; plant growth promoting bacteria; biofertilizerReferences
Aisyah, N., Zulkifli, L., & Rasmi, D. (2023). Isolation of endophytic bacteria and fungi from soursop (Annona muricata L.) and bioactivity test as antimicrobial against Eschericia coli, Staphylococcus epidermidis, and Candida albicans. Jurnal Pijar Mipa. https://doi.org/https://doi.org/10.29303/jpm.v18i2.3834
Ambawade, M., Patil, D., Pathade, G., & Mali, G. (2024). Indole acetic acid (IAA) production by endophytic bacterial isolate Agrobacterium tumefaciens BE-1 from roots of Musa acuminata. Research Journal of Biotechnology. https://doi.org/https://doi.org/10.25303/1904rjbt032039
Bhandari, G., Choudhary, S., Deogaonkar, A., Kumar, D., Miglani, K., Gupta, S., Joshi, S., Mittal, A., & Gangola, S. (2025). Isolation and Characterization of Plant Growth Promoting Endophytes from Linum Usitatissimum. Research in Ecology. https://doi.org/https://doi.org/10.30564/re.v7i2.9406.
Chawngthu, L., Hnamte, R., & Lalfakzuala, R. (2020). Isolation and Characterization of Rhizospheric Phosphate Solubilizing Bacteria from Wetland Paddy Field of Mizoram, India. Geomicrobiology Journal, 37, 366–375. https://doi.org/https://doi.org/10.1080/01490451.2019.1709108
Dong, M., Yang, Z., Cheng, G., Peng, L., Xu, Q., & Xu, J. (2018). Diversity of the Bacterial Microbiome in the Roots of Four Saccharum Species: S. spontaneum, S. robustum, S. barberi, and S. officinarum. Frontiers in Microbiology, 9. https://doi.org/https://doi.org/10.3389/fmicb.2018.00267
Emami, S., Alikhani, H., Pourbabaee, A., Etesami, H., Motasharezadeh, B., & Sarmadian, F. (2020). Consortium of endophyte and rhizosphere phosphate solubilizing bacteria improves phosphorous use efficiency in wheat cultivars in phosphorus deficient soils. Rhizosphere. https://doi.org/https://doi.org/10.1016/j.rhisph.2020.100196
Fatimah, F., Fadilah, R., Millah, A., Nurhariyati, T., Irawan, B., Ni’matuzahroh, N., Affandi, M., Zuhri, A., Widhiya, E., Salsabila, S., & Ramly, Z. (2022). Ability Test of IAA (Indole-3-Acetic Acid) Hormone-Producing Endophytic Bacteria from Lamongan Mangrove. Jurnal Riset Biologi Dan Aplikasinya. https://doi.org/https://doi.org/10.26740/jrba.v4n1.p42-50
Fouda, A., Eid, A., Elsaied, A., El-Belely, E., Barghoth, M., Azab, E., Gobouri, A., & Hassan, S. (2021). Plant Growth-Promoting Endophytic Bacterial Community Inhabiting the Leaves of Pulicaria incisa (Lam.) DC Inherent to Arid Regions. Plants, 10. https://doi.org/https://doi.org/10.3390/plants10010076.
Hao, S., Su, W., & Li, Q. (2020). Adaptive roots of mangrove Avicennia marina: Structure and gene expressions analyses of pneumatophores. The Science of the Total Environment, 757(143994). https://doi.org/https://doi.org/10.1016/j.scitotenv.2020.143994
Hawkesford, M., Horst, W., Kichey, T., Lambers, H., Schjoerring, J., Møller, I., & White, P. (2012). Functions of macronutrients. https://doi.org/https://doi.org/10.1016/B978-0-12-384905-2.00006-6.
Holt, J. G., Krieg, N. R., Sneath, P. H. A., Staley, J. T., & Williams, S. T. (1994). Bergey’s Manual of Determinative Bacteriology. Lippincott Wiliiams & Wilkins.
Kaur, C., Selvakumar, G., & Upreti, K. (2021). Organic Acid Profiles of Phosphate Solubilizing Bacterial Strains in the Presence of Different Insoluble Phosphatic Sources Under In vitro Buffered Conditions. Journal of Pure and Applied Microbiology, 15(2), 1006–1015. https://doi.org/https://doi.org/10.22207/jpam.15.2.59
Khan, A., Halo, B., Elyassi, A., Ali, S., Ali, S., Al-Hosni, K., Hussain, J., Al‐Harrasi, A., & Lee, I. (2016). Indole acetic acid and ACC deaminase from endophytic bacteria improves the growth of Solanum lycopersicum. Electronic Journal of Biotechnology, 21, 58–64. https://doi.org/https://doi.org/10.1016/j.ejbt.2016.02.001.
Khianngam, S., Meetum, P., Chiangmai, P., & Tanasupawat, S. (2023). Identification and Optimisation of Indole-3-Acetic Acid Production of Endophytic Bacteria and Their Effects on Plant Growth. Tropical Life Sciences Research, 34, 219–239. https://doi.org/https://doi.org/10.21315/tlsr2023.34.1.12
Kumar, V., Chourasia, H., Rajani, K., & Kumar, R. (2024). Exploration and Characterization of High-Efficiency Phosphate-Solubilizing Bacteria Isolates from Chickpea Rhizospheric Soil. International Journal of Bio-Resource and Stress Management, 15(1). https://doi.org/https://doi.org/10.23910/1.2024.4987a
Lebrazi, S., Niehaus, K., Bednarz, H., Fadil, M., Chraibi, M., & Fikri-Benbrahim, K. (2020). Screening and optimization of indole-3-acetic acid production and phosphate solubilization by rhizobacterial strains isolated from Acacia cyanophylla root nodules and their effects on its plant growth. Journal of Genetic Engineering & Biotechnology, 18. https://doi.org/https://doi.org/10.1186/s43141-020-00090-2
Lemos-Lucumí, C., Cárdenas-Hernández, V., & Toro-Perea, N. (2025). Metagenomic and metatranscriptomic exploration of Avicennia germinans L.: Endophytic microbiome of leaves and roots. Microbiological Research, 300(128287). https://doi.org/https://doi.org/10.1016/j.micres.2025.128287
Maulidia, V., Sriwati, R., Soesanto, L., Syamsuddin, Hamaguchi, T., & Hasegawa, K. (2021). Endophytic bacteria isolated from higher plant in Aceh, Indonesia, and their chemical compounds activity against Fusarium oxysporum f. sp. lycopersici. Egyptian Journal of Biological Pest Control, 31(2), 1–7. https://doi.org/https://doi.org/10.1186/s41938-021-00379-5
Michael, T., Madigan, K. S. B., Daniel, H. B., Sattley, W. M., & David, A. S. (2017). Brock Biology of Microorganisms (15th Edition) (15th ed.). Pearson.
Nur, S., Hidayati, I., Zulkifli, L., Sedijani, P., Ayu, D., & Rasmi, C. (2024). Antagonistic Test of Endophytic Bacteria of Chili Pepper Roots Producing Siderophores and Hydrolase Enzymes against Plant Pathogenic Bacteria Ralstonia Solanacearum. Jurnal Biologi Tropis, 24(4), 857–867.
Palit, K., Rath, S., Chatterjee, S., & Das, S. (2022). Microbial diversity and ecological interactions of microorganisms in the mangrove ecosystem: Threats, vulnerability, and adaptations. Environmental Science and Pollution Research, 29, 32467-32512. https://doi.org/https://doi.org/10.1007/s11356-022-19048-7
Pašakinskienė, I., Stakelienė, V., Matijošiūtė, S., & Martūnas, J. (2024). Diversity of Endophytic Fungi and Bacteria Inhabiting the Roots of the Woodland Grass, Festuca gigantea (Poaceae). Diversity. 16(8), 453. https://doi.org/https://doi.org/10.3390/d16080453
Prasgi, H., & Cahyani, V. (2025). Potential plant growth promoting activity of root endophytic and rhizospheric bacteria isolated from mahogany and siratro in Alas Bromo, Indonesia. IOP Conference Series: Earth and Environmental Science, 1463. https://doi.org/https://doi.org/10.1088/1755-1315/1463/1/012015.
Ramadhani, I., Rohadi, H., Yuliani, Y., & Ilyas, M. (2021). Study on Endophytic Fungi Associated with Moringa oleifera Lam. Collected from Lombok Island, West Nusa Tenggara. Annales Bogorienses, 24(2), 66–73. https://doi.org/https://ejournal.brin.go.id/annales/article/view/4282
Sánchez-González, M., Mora-Herrera, M., Wong-Villarreal, A., De La Portilla-López, N., Sánchez-Paz, L., Lugo, J., Vaca-Paulín, R., Del Águila, P., & Yáñez-Ocampo, G. (2022). Effect of pH and Carbon Source on Phosphate Solubilization by Bacterial Strains in Pikovskaya Medium. Microorganisms, 11. https://doi.org/https://doi.org/10.3390/microorganisms11010049
Silvani, V., Fracchia, S., Fernández, L., Pérgola, M., & Godeas, A. (2008). A simple method to obtain endophytic microorganisms from field-collected roots. Soil Biology & Biochemistry, 40(1259–1263). https://doi.org/https://doi.org/10.1016/j.soilbio.2007.11.022
Subedi, S., Allen, P., Vidales, R., Sternberg, L., Ross, M., & Afkhami, M. (2022). Salinity legacy: Foliar microbiome’s history affects mutualist-conferred salinity tolerance. Ecology, e3679. https://doi.org/https://doi.org/10.1002/ecy.3679
Suleman, M., Yasmin, S., Rasul, M., Yahya, M., Atta, B., & Mirza, M. (2018). Phosphate solubilizing bacteria with glucose dehydrogenase gene for phosphorus uptake and beneficial effects on wheat. PLoS ONE, 13. https://doi.org/https://doi.org/10.1371/journal.pone.0204408.
Sun, W., & Shahrajabian, M. (2025). Biostimulant and Beyond: Bacillus spp., the Important Plant Growth-Promoting Rhizobacteria (PGPR)-Based Biostimulant for Sustainable Agriculture. Earth Systems and Environment. https://doi.org/https://doi.org/10.1007/s41748-024-00552-4
Teymouri, M., Akhtari, J., Karkhane, M., & Marzban, A. (2016). Assessment of phosphate solubilization activity of Rhizobacteria in mangrove forest. Biocatalysis and Agricultural Biotechnology, 5, 168–172. https://doi.org/10.1016/j.bcab.2016.01.012
Tripathi, S., Srivastava, P., Devi, R. S., & Bhadouria, R. (2020). Influence of synthetic fertilizers and pesticides on soil health and soil microbiology. In Agrochemicals Detection, Treatment and Remediation. LTD. https://doi.org/10.1016/B978-0-08-103017-2.00002-7
Utami, A., & Munarti, M. (2020). Isolation and Characterization of Endophytic Bacteria in Ciplukan Plant (Physalis angulata). Indonesian Journal of Biology Education, 3(1). https://doi.org/https://doi.org/10.31002/ijobe.v3i1.2293
Walia, A., Guleria, S., Chauhan, A., & Mehta, P. (2017). Endophytic Bacteria: Role in Phosphate Solubilization. 61–93. https://doi.org/https://doi.org/10.1007/978-3-319-66544-3_4.
Wang, Y., Duan, Y., Chen, N., Ding, W., Liu, Y., & Xing, S. (2025). Integrated physiological, transcriptomic, and metabolomic analyses of Chrysanthemum ‘Boju’ under excessive indole-3-acetic acid stress. Frontiers in Plant Science, 16. https://doi.org/https://doi.org/10.3389/fpls.2025.1531585
Wang, Y., Luo, D., Xiong, Z., Wang, Z., & Gao, M. (2022). Changes in rhizosphere phosphorus fractions and phosphate-mineralizing microbial populations in acid soil as influenced by organic acid exudation. Soil and Tillage Research, 225(105543). https://doi.org/https://doi.org/10.1016/j.still.2022.105543
Wayan, N., Diah, A., Zulkifli, L., Ayu, D., & Rasmi, C. (2024). Exploration of P-Solubilizing and IAA-producing Rhizobacteria from Saline Environments : Their Effects on Vigna radiata Growth-promotion. Jurnal Biologi Tropis, 24(4), 797–806.
Zhang, B., Li, P., Wang, Y., Wang, J., Liu, X., Wang, X., & Hu, X. (2021). Characterization and synthesis of indole-3-acetic acid in plant growth promoting Enterobacter sp. RSC Advances, 11, 31601–31607. https://doi.org/https://doi.org/10.1039/d1ra05659j
Zhang, P., Jin, T., Sahu, S., Xu, J., Shi, Q., Liu, H., & Wang, Y. (2019). The Distribution of Tryptophan-Dependent Indole-3-Acetic Acid Synthesis Pathways in Bacteria Unraveled by Large-Scale Genomic Analysis. Molecules, 24. https://doi.org/https://doi.org/10.3390/molecules24071411
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