Growth-stimulating effect of symbiotic microorganisms on sorghum under water deficit conditions

   Sorghum bicolor is one of the crops capable of maintaining productivity under water deficit conditions. Biological preparations based on effective strains of bacteria and arbuscular mycorrhizal (АМ) fungi are actively introduced into agricultural production. These preparations improve mineral nutrition of plants, as well as increase adaptation to various stress factors, including sorghum plants. The effect of microbial preparations on the level of root colonization by AM fungi and its effect on the productivity of S. bicolor under water deficit conditions was considered. The effect of Funnelliformis
mosseae 1-16 association and the biopreparation Microbiocom-Agro on sorghum variety Krymbel was investigated. The pot experiment was conducted on sterile sand-vermiculite mixture. Water and nutrient regime were regulated by artificial irrigation. To create drought conditions, 30 % of the lowest moisture content of the substrate was maintained in the vessels, with optimal conditions – 60 %. Microbiocom-Agro and the F. mosseae 1-16 association have a positive effect on the growth and development of S. bicolor under water deficit conditions, increasing the height of plants by 6.6–11.5 % and dry weight by 6.3–30.8 %. This was promoted by intensification of colonization of the plant roots by 1-16 AM association by 14.7 % under the action of the bacterial preparation. It was shown that the microorganisms used contributed to a significant increase in the content of phosphorus and potassium in the leaves of grain sorghum by 29.8–60.6 % compared to the control without treatment, which was positively correlated with the crop productivity. These indicators also depended on the development of AM 1-16 fungi association in the roots of the studied plant with an average degree of correlation (r = 0,46). It was confirmed that sorghum, as a drought-resistant crop, is able to withstand a significant time with substrate desiccation, but arbuscular mycorrhizal fungi and associative bacteria are able to support plants in time of stress and bring them out of it faster.

1. Hassan A.M., Ahmed M.F., Rashed M.A. Performance and transcriptomic analysis of sorghum bicolor responding to drought stress. SABRAO Journal of Breeding and Genetics, 2022, vol. 54 (4), pp. 814–825. DOI: 10.54910/sabrao2022.54.4.12.

2. Kamali S., Mehraban A. Nitroxin and arbuscular mycorrhizal fungi alleviate negative effects of drought stress on Sorghum bicolor yield through improving physiological and biochemical characteristics. Plant Signal Behavior, 2020, vol. 15 (11), e: 1813998. DOI: 10.1080/15592324.2020.1813998.

3. Abdurashytova E.R., Melnichuk T.N., Abdurashytov S.F., Egovtseva A.Yu., Turin E.N., Gongalo A.A. Adaptability of the Sorghum Bicolor Rhizosphere Microbiocoenosis Inoculated by Microbial Agents in Southern Chernozem Soils. Russian Agricultural Sciences, 2022, vol. 48, no. 3, pp. 212–218. DOI: 10.3103/s1068367422030028.

4. Noceto P.A., Bettenfeld P., Boussageon R., Hériché M., Sportes A., Van Tuinen D., Courty P.-E., Wipf D. Arbuscular mycorrhizal fungi, a key symbiosis in the development of quality traits in crop production, alone or combined with plant growth-promoting bacteria. Mycorrhiza, 2021, vol. 31 (6), pp. 655–669. DOI: 10.1007/s00572-021-01054-1.

5. Figueiredo A.F., Boy J. Guggenberger G. Common Mycorrhizae Network : A Review of the Theories and Mechanisms Behind Underground Interactions. Frontiers Fungal Biology, 2021, vol. 2, e: 735299. DOI: 10.3389/ffunb.2021.735299.

6. Püschel D., Bitterlich M., Rydlová J., Jansa J. Facilitation of plant water uptake by an arbuscular mycorrhizal fungus: a Gordian knot of roots and hyphae. Mycorrhiza, 2020, vol. 30, pp. 299–313. DOI: 10.1007/s00572-020-00949-9.

7. Wang D., Ni Y., Xie K., Li Y., Wu W., Shan H., Cheng B., Li X. Aquaporin ZmTIP2;3 Promotes Drought Resistance of Maize through Symbiosis with Arbuscular Mycorrhizal Fungi. International Journal Molecular Sciences, 2024, vol. 25 (8), е: 4205. DOI: 10.3390/ijms25084205.

8. Ullah A., Gao D., Wu F. Common mycorrhizal network: the predominant socialist and capitalist responses of possible plant–plant and plant–microbe interactions for sustainable agriculture. Frontieres in Microbiology, 2024, vol. 15, e: 1183024. DOI: 10.3389/fmicb.2024.1183024.

9. Behrooz A., Vahdati K., Rejali F., Lotfi M., Sarikhani S., Leslie C. Arbuscular Mycorrhiza and Plant Growth-promoting Bacteria Alleviate Drought Stress in Walnut. HortScience, 2019, vol. 54 (6), pp. 1087–1092. DOI: 10.21273/HORTSCI13961-19.

10. Yu L., Zhang H., Zhang W., Liu K., Liu M., Shao X. Cooperation between arbuscular mycorrhizal fungi and plant growth-promoting bacteria and their effects on plant growth and soil quality. Peer Journal, 2022, vol. 10, e: 13080. DOI: 10.7717/peerj.13080.

11. Nanjundappa A., Bagyaraj D.J., Saxena A.K., Chakdar H. Interaction between arbuscular mycorrhizal fungi and Bacillus spp. in soil enhancing growth of crop plants. Fungal Biology and Biotechnology, 2019, vol. 6 (23). DOI: 10.1186/s40694-019-0086-5.

12. Nacoon S., Jogloy S., Riddech N., Mongkolthanaruk W., Kuyper T., Boonlue S. Interaction between Phosphate Solubilizing Bacteria and Arbuscular Mycorrhizal Fungi on Growth Promotion and Tuber Inulin Content of Helianthus tuberosus L. Scientific Reports, 2020, vol. 10, e: 4916. DOI: 10.1038/s41598-020-61846-x.

13. Raklami A., Bechtaoui N., Tahiri A., Anli M., Meddich A., Oufdou K. Use of Rhizobacteria and Mycorrhizae Consortium in the Open Field as a Strategy for Improving Crop Nutrition, Productivity and Soil Fertility. Frontieres in Microbiology, 2019, vol. 10, e: 01106. DOI: 10.3389/fmicb.2019.01106.

14. Seregina I.I., Nilovskaya N.T. Photosynthetic activity and donor-acceptor relations of spring wheat plants in the application of molybdenum-acid ammonium in drought conditions. Agrokhimiia = Agricultural Chemistry, 2020, no. 7, pp. 26–35. (In Russian).

15. Qi S., Wang J., Wan L., Dai Z., Da Silva Matos D.M., Du D., Egan S., Bonser S.P., Thomas T., Moles A.T. Arbuscular Mycorrhizal Fungi Contribute to Phosphorous Uptake and Allocation Strategies of Solidago canadensis in a Phosphorous-Deficient Environment. Frontiers in Plant Science, 2022, vol. 13, e: 831654. DOI: 10.3389/fpls.2022.831654.