Integrated biocontrol of okra root rot caused by Fusarium solani and Macrophomina phaseolina using Pseudomonas fluorescens and Saccharomyces cerevisiae

Articles in Press

Document Type : Research Paper

Authors

Plant Protection Department, College of Agriculture, University of Misan, Iraq.

10.22103/jab.2026.27237.1913

Abstract

Objective
This study evaluated the antagonistic potential of the yeast Saccharomyces cerevisiae and the bacterium Pseudomonas fluorescens against Fusarium solani and Macrophomina phaseolina, the causal agents of okra (Abelmoschus esculentus L.) root rot and seedling damping-off. The research involved isolation and identification of the pathogens, assessment of their pathogenic variability, and evaluation of biological control agents under laboratory and greenhouse conditions.
Materials and methods
Three isolates of F. solani and two isolates of M. phaseolina were obtained from infected okra plants collected from different locations. Significant variation in pathogenicity was observed among the isolates. The isolate F1 of F. solani exhibited the highest virulence, causing a significant reduction in seed germination and increasing seedling mortality by 43.2% and 49.4%, respectively, compared with the untreated control.
Results
In vitro assays demonstrated that P. fluorescens effectively inhibited the radial growth of F. solani and M. phaseolina by 48.36% and 64.7%, respectively. Similarly, S. cerevisiae exhibited significant antifungal activity, particularly at the fifth dilution, where growth inhibition reached 74.1% for F. solani and 76.1% for M. phaseolina. These findings demonstrate that both biological agents significantly suppressed fungal growth under in vitro conditions. Pathogenicity tests confirmed that infection with F. solani and M. phaseolina significantly reduced seed germination and increased seedling mortality. However, application of biological treatments reduced disease severity. Among all treatments, the combined application of M. phaseolina with P. fluorescens produced the best results, significantly improving germination percentage and reducing seedling mortality compared to pathogen-only treatments. Greenhouse experiments further revealed that both S. cerevisiae and P. fluorescens, applied individually or in combination, significantly enhanced seed germination, chlorophyll content, vegetative growth, and leaf area. Moreover, the combined treatment exhibited a strong synergistic effect in suppressing pathogen activity, reducing disease incidence and severity, and promoting overall plant growth performance.
Conclusion
Overall, the results of this study demonstrate that S. cerevisiae and P. fluorescens are promising eco-friendly biological control agents that can be effectively used in integrated management strategies for controlling okra root rot disease caused by F. solani and M. phaseolina. These findings support the development of sustainable disease management approaches that reduce reliance on chemical fungicides while improving plant health and productivity.

Keywords

References

Abbott, W. S. (1925). A method of computing the effectiveness of an insecticide. Journal of Economic Entomology, 18(2), 265–267. https://doi.org/10.1093/jee/18.2.265a
Abd-Alrahman, H. A., & Aboud, F. S. (2021). Response of sweet pepper plants to foliar application of compost tea and dry yeast under soilless conditions. Bulletin of the National Research Centre, 45, Article 119. https://doi.org/10.1186/s42269-021-00578-y
Abd-Elbaky, A. A., Yousef, H., & Abd El-Maged, M. S. (2021). Effect of foliar application of yeast (Saccharomyces cerevisiae) on controlling downy mildew disease and yield production of onion. Middle East Journal of Agriculture Research, 10(2), 629–636.
Abiala, M. A., Oleru, K., Balogun, T., Saharia, M., Opere, B., & Sahoo, L. (2021). Soil borne Fusarium solani exhibited pathogenic effect on tomato cultivars in Nigeria. Archives of Phytopathology and Plant Protection, 54(3–4), 137–151. https://doi.org/10.1080/03235408.2020.1824338
Al-Ghazali, N. A., Gamaz, B. A. N., Abu-Duka, A. B., & Kamel, L. A. (2025). First record of Fusarium solani as a causal agent of root rot and damping-off disease in Acacia mangium and its in vitro control in Karbala Province, Iraq. Basrah Journal of Agricultural Sciences, 38(Special Issue), 326–335. https://doi.org/10.37077/25200860.2025.38.sp.29
Al-Juthery, H. W., Ali, E. H. A. M., Al-Ubori, R. N., Al-Shami, Q. N. M., & Al-Taey, D. K. (2020). Role of foliar application of nano NPK, micro fertilizers and yeast extract on growth and yield of wheat. International Journal of Agricultural and Statistical Sciences, 16(Supplement 1), 1295–1300.
Appiah, A. S., Amiteye, S., Boateng, F., & Amoatey, H. (2020). Evaluation of okra (Abelmoschus esculentus L. Moench) cultivars for resistance to okra mosaic virus and okra yellow vein mosaic virus. Australasian Plant Pathology, 49, 541–550. https://doi.org/10.1007/s13313-020-00727-3
Arnon, D. I. (1949). Copper enzymes in isolated chloroplasts: Polyphenol oxidase in Beta vulgaris. Plant Physiology, 24(1), 1–15. https://doi.org/10.1104/pp.24.1.1
Benchasri, S. (2012). Okra (Abelmoschus esculentus L. Moench) as a valuable vegetable of the world. Ratarstvo i Povrtarstvo, 49, 105–112. https://doi.org/10.5937/ratpov49-1172
Chalutz, E., Lieberman, M., & Sisler, H. D. (1977). Methionine-induced ethylene production by Penicillium digitatum. Plant Physiology, 60(3), 402–406. https://doi.org/10.1104/pp.60.3.402
Dean, R., Van Kan, J. A. L., Pretorius, Z. A., Hammond-Kosack, K. E., Di Pietro, A., Spanu, P. D., Rudd, J. J., Dickman, M., Kahmann, R., Ellis, J., & Foster, G. D. (2012). The top 10 fungal pathogens in molecular plant pathology. Molecular Plant Pathology, 13(4), 414–430. https://doi.org/10.1111/j.1364-3703.2011.00783.x
Elkhalifa, A. E. O., Alshammari, E., Adnan, M., Alcantara, J. C., Awadelkareem, A. M., Eltoum, N. E., Mehmood, K., Panda, B. P., & Ashraf, S. A. (2021). Okra (Abelmoschus esculentus) as a potential dietary medicine with nutraceutical importance for sustainable health applications. Molecules, 26(3), Article 696. https://doi.org/10.3390/molecules26030696
El-Rayes, M., Ali, I., Abd El-Nabi, H., Morsy, K., & Khalil, M. (2022). Bioagents as safe control agents against Fusarium oxysporum, Rhizoctonia solani, Macrophomina phaseolina of cluster bean (Cyamopsis tetragonoloba L.). Egyptian Journal of Phytopathology, 50(2), 138–150. https://doi.org/10.21608/ejp.2022.179022.1077
El-Sayed, S. (2022). Collaborative potentialities of Trichoderma spp. and Saccharomyces cerevisiae against damping-off and root rot diseases of faba bean. Egyptian Journal of Phytopathology, 50(1), 65–78. https://doi.org/10.21608/ejp.2022.134177.1060
FAOSTAT. (2022). Crop and livestock products. Food and Agriculture Organization of the United Nations. https://www.fao.org/faostat/en/#home
Haas, D., & Défago, G. (2005). Biological control of soil-borne pathogens by fluorescent pseudomonads. Nature Reviews Microbiology, 3, 307–319. https://doi.org/10.1038/nrmicro1129
Islam, M. S., Haque, M. S., Islam, M. M., Emdad, E. M., Halim, A., Hossen, Q. M. M., & Alam, M. (2012). Tools to kill: Genome of one of the most destructive plant pathogenic fungi Macrophomina phaseolina. BMC Genomics, 13, Article 493. https://doi.org/10.1186/1471-2164-13-493
Lahlali, R., Ezrari, S., Radouane, N., Kenfaoui, J., Esmaeel, Q., El Hamss, H., Belabess, Z., & Barka, E. A. (2022). Biological control of plant pathogens: A global perspective. Microorganisms, 10(3), Article 596. https://doi.org/10.3390/microorganisms10030596
Lugtenberg, B., & Kamilova, F. (2009). Plant-growth-promoting rhizobacteria. Annual Review of Microbiology, 63, 541–556. https://doi.org/10.1146/annurev.micro.62.081307.162918
Ma, L. J., Geiser, D. M., Proctor, R. H., Rooney, A. P., O'Donnell, K., Trail, F., Gardiner, D. M., Manners, J. M., & Kazan, K. (2013). Fusarium pathogenomics. Annual Review of Microbiology, 67, 399–416. https://doi.org/10.1146/annurev-micro-092412-155650
Mankoti, M., Pandit, N. K., Meena, S. S., & Mohanty, A. (2024). Investigating the genomic and metabolic abilities of PGPR Pseudomonas fluorescens in promoting plant growth and fire blight management. Molecular Genetics and Genomics, 299, Article 110. https://doi.org/10.1007/s00438-024-02198-3
Marquez, N., Giachero, M. L., Declerck, S., & Ducasse, D. A. (2021). Macrophomina phaseolina: General characteristics of pathogenicity and methods of control. Frontiers in Plant Science, 12, Article 634397. https://doi.org/10.3389/fpls.2021.634397
Meiriani, & Tarigan, D. M. (2024). Utilization azolla liquid organic fertilizer with goat manure to enhance organic okra (Abelmoschus esculentus L. Moench) production. IOP Conference Series: Earth and Environmental Science, 1302(1), Article 012030. https://doi.org/10.1088/1755-1315/1302/1/012030
Meng, Y., Wang, J., Xu, H., Yu, Y., & Liang, Y. (2025). A novel plate compartment–confrontation method discovered that volatile organic compounds produced by Saccharomyces cerevisiae inhibit Botrytis cinerea and Fusarium graminearum. Journal of Fungi, 11(6), Article 418. https://doi.org/10.3390/jof11060418
Nagarajkumar, M., Bhaskaran, R., & Velazhahan, R. (2004). Involvement of secondary metabolites and extracellular lytic enzymes produced by Pseudomonas fluorescens in inhibition of Rhizoctonia solani, the rice sheath blight pathogen. Microbiological Research, 159(1), 73–81. https://doi.org/10.1016/j.micres.2004.01.005
Nelson, P. E., Toussoun, T. A., & Marasas, W. F. O. (1983). Fusarium species: An illustrated manual for identification. Pennsylvania State University Press.
Ongena, M., & Jacques, P. (2008). Bacillus lipopeptides: Versatile weapons for plant disease biocontrol. Trends in Microbiology, 16(3), 115–125. https://doi.org/10.1016/j.tim.2007.12.009
Ounis, S., Turóczi, G., & Kiss, J. (2024). Arthropod pests, nematodes, and microbial pathogens of okra (Abelmoschus esculentus) and their management—A review. Agronomy, 14(12), Article 2841. https://doi.org/10.3390/agronomy14122841
Podgórska-Kryszczuk, I., Solarska, E., & Kordowska-Wiater, M. (2022). Biological control of Fusarium culmorum, Fusarium graminearum and Fusarium poae by antagonistic yeasts. Pathogens, 11(1), Article 86. https://doi.org/10.3390/pathogens11010086
Raaijmakers, J. M., & Mazzola, M. (2012). Diversity and natural functions of antibiotics produced by beneficial and plant pathogenic bacteria. Annual Review of Phytopathology, 50, 403–424. https://doi.org/10.1146/annurev-phyto-081211-172908
Reznikov, S., Chiesa, M. A., Pardo, E. M., De Lisi, V., Bogado, N., González, V., Ledesma, F., Morandi, E. N., Ploper, L. D., & Castagnaro, A. P. (2019). Soybean-Macrophomina phaseolina-specific interactions and identification of a novel source of resistance. Phytopathology, 109(1), 63–73. https://doi.org/10.1094/PHYTO-08-17-0287-R
Smiley, R. W. (2019). Mechanized method to inoculate field soil to evaluate Fusarium crown rot of wheat. Plant Disease, 103(11), 2857–2864. https://doi.org/10.1094/PDIS-01-19-0215-RE
Spadaro, D., & Droby, S. (2016). Development of biocontrol products for postharvest diseases control. Annual Review of Phytopathology. https://doi.org/10.1146/annurev-phyto-080615-100154
Summerell, B. A., Salleh, B., & Leslie, J. F. (2003). A utilitarian approach to Fusarium identification. Plant Disease, 87(2), 117. https://doi.org/10.1094/PDIS.2003.87.2.117
Taylor, T. B., Silby, M. W., & Jackson, R. W. (2025). Pseudomonas fluorescens. Trends in Microbiology, 33(2). https://doi.org/10.1016/j.tim.2024.11.005
United States Environmental Protection Agency. (2023). Integrated pest management (IPM) principles. https://www.epa.gov/safepestcontrol/integrated-pest-management-ipm-principles
Weller, D. M. (2007). Pseudomonas biocontrol agents of soilborne pathogens: Looking back over 30 years. Phytopathology, 97(2), 250–256. https://doi.org/10.1094/PHYTO-97-2-0250
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Available Online from 06 July 2026

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