The Impact of Symbiosis with Beneficial Microbes in Soil on Pistacia Vera

Introduction: Pistacia vera (pistachio) is a strategic crop in Iran. Some stressors, such as pathogen invasion, drought and salinity negatively affect pistachio growth and production. Chemical methods which have been employed for a long time, can be a serious threat to the environment and human health. Establishing appropriate symbiosis between pistachios and beneficial microorganisms of soil has recently attracted a lot of attention, which could replace chemical methods. Results: Mycorrhizal fungi are among the most common symbionts of pistachios. These fungi increase the root surface for the uptake of water and some immobile elements, especially phosphorous. Trichoderma is a free-living fungus which can establish symbiosis with pistachios to protect them against different soil pathogens, apart from having some nutritional benefits. Some soil-borne bacteria can also provide symbiosis with pistachio roots as plant growth-promoting rhizobacteria. They improve plant growth by increasing the uptake of some elements, such as phosphorous, iron, and zinc, in addition to producing some phytohormones. Conclusion: Screening and selecting the most suitable symbionts is a major step in providing useful symbiosis between pistachios and soil microorganisms. Co-inoculation with several compatible microbes could also be a good solution for benefiting plants and overcoming environmental stresses. However, it needs more investigations.