**7. Conclusion**

The presence of cyanobacteria in the soil is a positive indicator of the availability of organic matter, the support of oxygen, and the synthesis of hormones, amino acids, and vitamins, in addition to increasing the solubility of phosphates and enhancing the efficiency of fertilizers in plants while reducing the soil content of oxidants and salinity. Additionally, it plays a crucial role in nitrogen fixation, which is a major source of plant nutrition. Moreover, cyanobacteria promote the production of plant hormones and play an important role in combating many phytopathogens as antifungal, antibacterial, antinematode, and antiviral. It is clear from the above that cyanobacteria play an integral role in the sustainability of agriculture, as they work to improve the physiology of the plant and protect it against abiotic stress and attack by phytopathogens. Therefore, cyanobacteria should be applied on a larger scale in modern agricultural systems.
