Formation of a binary diazotroph composition and its application in a sunflower agrocenosis
Abstract
Purpose. To substantiate the formation of a binary composition based on Azotobacter chroococcum 2.1 and Azospirillum brasilense 137 strains and to evaluate its effectiveness based on its effects on sunflower plants and the abundance of culturable groups of rhizosphere microorganisms under different agricultural practices. Methods. The research was conducted in the Ukrainian Polissia on sodpodzolic light loamy soil. The following methods were used: microbiological (isolation of isolates, determination of cell titer, cultivation on selective media), gas-chromatographic (determination of potential nitrogen-fixing activity), field, biometric, and statistical. Results. In the pot experiment, among twenty variants, the combination of A. chroococcum 2.1 and A. brasilense 137 strains provided the best average indicators of potential nitrogen-fixing activity and dry mass accumulation. It was established that the highest laboratory germination, germination energy, radicle length, and seedling dry mass were achieved at a component ratio of 1:1. During the flowering stage, the mean abundance of microorganisms cultured on Ashby and Döbereiner media was higher than in the uninoculated controls, whereas the response of other ecological-trophic groups depended on the agricultural practices applied. The biometric parameters of the plants and the physical properties of the seeds were highest under the combination of inoculation, deep loosening, and pre-emergence soil herbicides. Conclusions. The obtained data indicate that the diazotroph composition is a promising element of an ecologically balanced sunflower cultivation technology on sod-podzolic soils in the Polissia zone. The most favorable conditions for realizing the biological potential of the introduced diazotrophs were created by deep non-inversion tillage and lower direct herbicide exposure of growing plants compared with the post-emergence herbicide application scheme.
References
2. ДСТУ 4138-2002. Насіння сільськогосподарських культур. Методи визначання якості. [Чинний від 2004-01-01]. Вид. офіц. Київ : Держспоживстандарт України, 2003. 173 с.
3. ДСТУ 7011:2009. Соняшник. Технічні умови. [Чинний від 2010-01-01]. Вид. офіц. Київ : Держспоживстандарт України, 2010. 11 с.
4. Дука О. С., Козар С. Ф., Воробей Ю. О., Логоша О. В., Білоконська О. М. Ефективність бактеризації соняшнику діазотрофами за дії різних гербіцидів і способів обробітку ґрунту. Сільськогосподарська мікробіологія. 2025. Вип. 42. С. 72–82. DOI: 10.35868/1997-3004.42.72-82
5. Експериментальна ґрунтова мікробіологія : монографія / за ред. В. В. Волкогона. Київ : Аграрна наука, 2010. 464 с. ISBN 978-966-540-300-5.
6. Мазур С. О., Матусевич Г. Д. Вплив ґрунтових гербіцидів на біометричні показники та врожайність соняшнику. Збалансоване природокористування. 2023. № 1. С. 90–96. DOI: 10.33730/ 2310-4678.1.2023.278544
7. Методика державного сортовипробування сільсько-господарських культур. Вип. 1. Загальна частина / за ред. В. В. Волкодава. Київ : Алефа, 2000. 100 с.
8. Сидякіна О. В., Гамаюнова В. В. Сучасний стан та перспективи виробництва насіння соняшнику. Таврійський науковий вісник. 2023. № 131. С. 196–204. DOI: 10.32782/ 2226-0099.2023.131.25
9. Nitrogen fixing Azotobacter species as potential soil biological enhancers for crop nutrition and yield stability / A. Aasfar et al. Frontiers in Microbiology. 2021. Vol. 12. Art. 628379. DOI: 10.3389/fmicb.2021.628379
10. Photosynthetic performance of the imidazolinone resistant sunflower exposed to single and combined treatment by the herbicide imazamox and an amino acid extract / D. A. Balabanova et al. Frontiers in Plant Science. 2016. Vol. 7. Art. 1559. DOI: 10.3389/fpls.2016.01559
11. The rhizosphere bacteriome is modified by wheat genotype and growth stage under increased imidazolinone herbicide residues / B. B. Dzoma et al. Biology and Fertility of Soils. 2025. Vol. 61. P. 717–733. DOI: 10.1007/s00374-025-01890-9
12. Fukami J., Cerezini P., Hungria M. Azospirillum: benefits that go far beyond biological nitrogen fixation. AMB Express. 2018. Vol. 8. Art. 73. DOI: 10.1186/s13568-018-0608-1
13. Bergey’s Manual of Systematic Bacteriology / G. M. Garrity et al. 2nd ed. Vol. 2, Part B: The Gammaproteobacteria; Part C: The Alpha-, Beta-, Delta-, and Epsilonproteobacteria. New York : Springer, 2005. DOI: 10.1007/ 0-387-28022-7; 10.1007/ 0-387-29298-5
14. Güler M., Öğütcü H. Isolation and characterization of plant growth promoting rhizobacteria (PGPR) from rhizosphere of Helianthus annuus L. International Journal of Agriculture, Environment and Food Sciences. 2024. Vol. 8, № 2. P. 412–429. DOI: 10.31015/jaefs.2024.2.16
15. Hinkelmann K., Kempthorne O. Design and Analysis of Experiments. Vol. 2: Advanced Experimental Design. 1st ed. Hoboken, NJ : John Wiley & Sons, 2005. 780 p. DOI: 10.1002/ 0471709948
16. Hinkelmann K., Kempthorne O. Design and Analysis of Experiments. Vol. 1: Introduction to Experimental Design. 2nd ed. Hoboken, NJ : John Wiley & Sons, 2008. 631 p. DOI: 10.1002/ 9780470191750
17. Liu X., Mei S., Falcão Salles J. Inoculated microbial consortia perform better than single strains in living soil: A meta-analysis. Applied Soil Ecology. 2023. Vol. 190. Art. 105011. DOI: 10.1016/j.apsoil.2023.105011
18. Menéndez E., Paço A. Is the application of plant probiotic bacterial consortia always beneficial for plants? Exploring synergies between rhizobial and non-rhizobial bacteria and their effects on agro-economically valuable crops. Life. 2020. Vol. 10, № 3. Art. 24. DOI: 10.3390/life10030024
19. Nwachukwu B. C., Ayangbenro A. S., Babalola O. O. Comparative study of microbial structure and functional profile of sunflower rhizosphere grown in two fields. BMC Microbiology. 2021. Vol. 21. Art. 337. DOI: 10.1186/s12866-021-02397-7
20. Plant growth-promoting bacteria as bioinoculants: Attributes and challenges for sustainable crop improvement / M. del C. Orozco-Mosqueda et al. Agronomy. 2021. Vol. 11, № 6. Art. 1167. DOI: 10.3390/agronomy11061167
21. Impact of herbicides on soil biology and function / M. T. Rose et al. Advances in Agronomy. 2016. Vol. 136. P. 133–220. DOI: 10.1016/bs.agron.2015.11.005
22. Schlüter S., Großmann C., Diel J., Wu G.-M., Tischer S., Deubel A., Rücknagel J. Long-term effects of conventional and reduced tillage on soil structure, soil ecological and soil hydraulic properties. Geoderma. 2018. Vol. 332. P. 10–19. DOI: 10.1016/j.geoderma.2018.07.001
23. Sun R., Li W., Dong W., Tian Y., Hu C., Liu B. Tillage changes vertical distribution of soil bacterial and fungal communities. Frontiers in Microbiology. 2018. Vol. 9. Art. 699. DOI: 10.3389/fmicb.2018.00699
24. Thiour-Mauprivez C., Martin-Laurent F., Calvayrac C., Barthelmebs L. Effects of herbicide on nontarget microorganisms: towards a new class of biomarkers? Science of the Total Environment. 2019. Vol. 684. P. 314–325. DOI: 10.1016/j.scitotenv.2019.05.230
25. Wang H., Ren W., Xu Y., Wang X., Ma J., Sun Y., Hu W., Chen S., Dai S., Song J., Jia J., Teng Y. Longterm herbicide residues affect soil multifunctionality and the soil microbial community. Ecotoxicology and Environmental Safety. 2024. Vol. 283. Art. 116783. DOI: 10.1016/j.ecoenv.2024.116783
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