Biological Systems: Theory and Innovation

Bacteria of Bacillus genus as efficient and safe plant protection agent against pathogenic microorganisms

Sofia Kozlova
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Abstract

The study aimed to establish correlation between antagonistic activity of Bacillus strains and their effect on plant growth and soil microbial balance. Experiment was based on combination of microbiological, physiological and statistical methods, including agar well method for determining antagonism, serial dilution method for counting colonies, triphenyl tetrazolium chloride method for assessing dehydrogenase activity, and analysis of variance (ANOVA) for result reliability verification. Experiment determined that B. subtilis has a higher inhibitory capacity than B. amyloliquefaciens, determining that average diameters of inhibition were 10-15% larger, while growth inhibition index was larger by 5-8%. Lesion index in Fusarium oxysporum dropped by 33.0 percentage points (p.p.) (from 53.8% to 20.8%), in Alternaria solani by 29.0 p.p., and in Pseudomonas syringae by 27.1 p.p. Proportion of healthy plants in control group improved from 51.5-56.3% to 86.2-87.3% with B. subtilis and 82.4-84.1% with B. amyloliquefaciens. Height, number of leaves and root mass improved by 20-40% compared to control, exceeding efficiency of biological standard by 5-10%, therefore demonstrating stimulative effect of biological products on plant growth. Experiment detected no phytotoxicity or soil degradation. Biological preparations ensured stable saprophyte (1.8 × 10⁶ CFU/g), actinomycetes (1.9 × 10⁶ CFU/g) and fungi (1.8 × 10⁵ CFU/g) count, while dehydrogenase activity reached 103% compared to control. Results of experiment confirmed that Bacillus subtilis and Bacillus amyloliquefaciens are efficient antagonists of phytopathogens and safe biostimulants that can improve productivity and stabilise soil microbiocenosis. They are an efficient, environmentally sustainable alternative to chemical fungicides in sustainable farming systems

Keywords

antagonism; biocontrol activity; damage index; environmental safety; rhizosphere

Suggested citation
Kozlova, S. (2025). Bacteria of Bacillus genus as efficient and safe plant protection agent against pathogenic microorganisms. Biological Systems: Theory and Innovation, 16(4), 101-117. https://doi.org/10.31548/biologiya/4.2025.101
References
  1. Abd-Elgawad, M.M.M. (2024). Bacillus species: Prospects and applications for the root-knot disease management. In Microbial biostimulants (pp. 79-105). New York: Apple Academic Press.
  2. Ajuna, H.B., Lim, H.-I., Moon, J.-H., Won, S.-J., Choub, V., Choi, S.-I., Yun, J.-Y., & Ahn, Y. S. (2024). The prospect of antimicrobial peptides from Bacillus species with biological control potential against insect pests and diseases of economic importance in agriculture, forestry and fruit tree production. Biotechnology & Biotechnological Equipment, 38(1), article number 2312115. doi: 10.1080/13102818.2024.2312115.
  3. Ali, A., et al. (2022). Antagonistic potential of bacterial species against fungal plant pathogens (FPP) and their role in plant growth promotion (PGP): A review. Phyton, 91(9), 1859-1877. doi: 10.32604/phyton.2022.021734.
  4. Ayaz, M., et al. (2023). Bacterial and fungal biocontrol agents for plant disease protection: Journey from lab to field, current status, challenges, and global perspectives. Molecules, 28(18), article number 6735. doi: 10.3390/molecules28186735.
  5. Blanco Crivelli, X., Cundon, C., Bonino, M.P., Sanin, M.S., & Bentancor, A. (2024). The complex and changing genus Bacillus: A diverse bacterial powerhouse for many applications. Bacteria, 3(3), 256-270. doi: 10.3390/bacteria3030017.
  6. Boulahouat, S., Cherif-Silini, H., Silini, A., Bouket, A.C., Luptakova, L., Alenezi, F.N., & Belbahri, L. (2023). Biocontrol efficiency of rhizospheric Bacillus against the plant pathogen Fusarium oxysporum: A promising approach for sustainable agriculture. Microbiology Research, 14(3), 892-908. doi: 10.3390/microbiolres14030062.
  7. Convention on Biological Diversity. (1992, June). Retrieved from https://zakon.rada.gov.ua/laws/show/995_030#Text.
  8. Dutilloy, E., Oni, F.E., Esmaeel, Q., Clément, C., & Barka, E.A. (2022). Plant beneficial bacteria as bioprotectants against wheat and barley diseases. Journal of Fungi, 8(6), article number 632. doi: 10.3390/jof8060632.
  9. El-Saadony, M.T., et al. (2022). Plant growth-promoting microorganisms as biocontrol agents of plant diseases: Mechanisms, challenges and future perspectives. Frontiers in Plant Science, 13, article number 923880. doi: 10.3389/fpls.2022.923880.
  10. Fessia, A., Barra, P., Barros, G., & Nesci, A. (2022). Could Bacillus biofilms enhance the effectivity of biocontrol strategies in the phyllosphere? Journal of Applied Microbiology, 133(4), 2148-2166. doi: 10.1111/jam.15596.
  11. Figueroa-Brambila, K.M., Escalante-Beltrán, A., Montoya-Martínez, A.C., Díaz-Rodríguez, A.M., López-Montoya, N.D., Parra-Cota, F.I., & de Los Santos-Villalobos, S. (2023). Bacillus cabrialesii: Five years of research on a novel species of biological control and plant growth-promoting bacteria. Plants, 12(13), article number 2419. doi: 10.3390/plants12132419.
  12. Jang, S., Choi, S.K., Zhang, H., Zhang, S., Ryu, C.M., & Kloepper, J.W. (2023). History of a model plant growth-promoting rhizobacterium, Bacillus velezensis GB03: From isolation to commercialization. Frontiers in Plant Science, 14, article number 1279896. doi: 10.3389/fpls.2023.1279896.
  13. Khan, A.R., Mustafa, A., Hyder, S., Valipour, M., Rizvi, Z.F., Gondal, A.S., Yousuf, Z., Iqbal, R., & Daraz, U. (2022). Bacillus spp. as bioagents: Uses and application for sustainable agriculture. Biology, 11(12), article number 1763. doi: 10.3390/biology11121763.
  14. Kolchyk, O.V., Borovuk, I.V., Buzun, A.I., Іllarionova, & Zazharska, N.M. (2024). Microorganisms’ growth inhibition in poultry meat using Bacillus spp. World’s Veterinary Journal, 14(3), 424-434.
  15. Kolomiiets, Y., Butsenko, L., Yemets, A., & Blume, Y. (2024). The use of PGPB-based bioformulations to control bacterial diseases of vegetable crops in Ukraine. The Open Agriculture Journal, 18(1), article number e18743315283724. doi: 10.2174/0118743315283724231220104524.
  16. Maciag, T., Kozieł, E., Rusin, P., Otulak-Kozieł, K., Jafra, S., & Czajkowski, R. (2023). Microbial consortia for plant protection against diseases: More than the sum of its parts. International Journal of Molecular Sciences, 24(15), article number 12227. doi: 10.3390/ijms241512227.
  17. Mahapatra, S., Yadav, R., & Ramakrishna, W. (2022). Bacillus subtilis impact on plant growth, soil health and environment: Dr. Jekyll and Mr. Hyde. Journal of Applied Microbiology, 132(5), 3543-3562. doi: 10.1111/jam.15480.
  18. Marisel, O.G., Yoania, R.R., Santiago, R.R., Alberto, Z.L.H., & Fernando, C.D.I. (2024). Bioprospecting a mountain-derived phosphorus-solubilizing bacterium: Bacillus thuringiensis B3 as a plant-growth promoter in lettuce and tomato horticultural crops. Scientia Horticulturae, 337, article number 113568. doi: 10.1016/j.scienta.2024.113568.
  19. Muthukumar, A., Raj, T.S., Prabhukarthikeyan, S.R., Kumar, R.N., & Keerthana, U. (2022). Pseudomonas and Bacillus: A biological tool for crop protection. In New and future developments in microbial biotechnology and bioengineering (pp. 145-158). Amsterdam: Elsevier. doi: 10.1016/B978-0-323-85577-8.00006-8.
  20. Ngalimat, M.S., Mohd Hata, E., Zulperi, D., Ismail, S.I., Ismail, M.R., Mohd Zainudin, N.A. I., Saidi, N.B., & Yusof, M.T. (2021). Plant growth-promoting bacteria as an emerging tool to manage bacterial rice pathogens. Microorganisms, 9(4), article number 682. doi: 10.3390/microorganisms9040682.
  21. Ortiz, A., & Sansinenea, E. (2022). The role of beneficial microorganisms in soil quality and plant health. Sustainability, 14(9), article number 5358. doi: 10.3390/su14095358.
  22. Ortiz, A., & Sansinenea, E. (2023). Genetically modified plants based on Bacillus genes and commercial Bacillus-based biopesticides for sustainable agriculture. Horticulturae, 9(9), article number 963. doi: 10.3390/horticulturae9090963.
  23. Phillips, J.M., & Hayman, D.S. (1970). Improved procedures for clearing roots and staining parasitic and vesicular-arbuscular mycorrhizal fungi for rapid assessment of infection. Transactions British Mycological Society, 55(1).
  24. Prabhukarthikeyan, S.R., et al. (2022). Bacillus rhizobacteria: A versatile biostimulant for sustainable agriculture. In New and future developments in microbial biotechnology and bioengineering (pp. 33-44). Amsterdam: Elsevier. doi: 10.1016/B978-0-323-85163-3.00009-0.
  25. Reshetnikov, M.V., & Patyka, V.P. (2023). Bacteria-antagonists of the agents of soryz bacterial diseases. Agricultural Science and Practice, 10(3), 46-60. doi: 10.15407/agrisp10.03.046.
  26. Sales, L.R., & Rigobelo, E.C. (2024). The role of Bacillus sp. in reducing chemical inputs for sustainable crop production. Agronomy, 14(11), article number 2723. doi: 10.3390/agronomy14112723.
  27. Serrão, C.P., Ortega, J.C.G., Rodrigues, P.C., & de Souza, C.R.B. (2024). Bacillus species as tools for biocontrol of plant diseases: A meta-analysis of twenty-two years of research, 2000-2021. World Journal of Microbiology and Biotechnology, 40(4), article number 110. doi: 10.1007/s11274-024-03935-x.
  28. Toma, R.C., Boiu-Sicuia, O.A., Diguță, F.C., Ciucă, M., Matei, F., & Cornea, C.P. (2023). Selected plant protection Bacillus strains increase food safeness by inhibiting human pathogenic bacteria. Romanian Agricultural Research, 40, 609-619. doi: 10.59665/rar4057.
  29. Tsotetsi, T., Nephali, L., Malebe, M., & Tugizimana, F. (2022). Bacillus for plant growth promotion and stress resilience: What have we learned? Plants, 11(19), article number 2482. doi: 10.3390/plants11192482.
  30. Vasantha-Srinivasan, P., Park, K.B., Kim, K.Y., Jung, W.J., & Han, Y.S. (2025). The role of Bacillus species in the management of plant-parasitic nematodes. Frontiers in Microbiology, 15, article number 1510036. doi: 10.3389/fmicb.2024.1510036.
  31. Vasques, N.C., Nogueira, M.A., & Hungria, M. (2024). Increasing application of multifunctional Bacillus for biocontrol of pests and diseases and plant growth promotion: Lessons from Brazil. Agronomy, 14(8), article number 1654. doi: 10.3390/agronomy14081654.
  32. Wang, H., Liu, R., You, M.P., Barbetti, M.J., & Chen, Y. (2021). Pathogen biocontrol using plant growth-promoting bacteria (PGPR): Role of bacterial diversity. Microorganisms, 9(9), article number 1988. doi: 10.3390/microorganisms9091988.