Chapter 16 Mycorrhiza: Plant Growth-Promoting and Biocontrol Agent Ability Under the Abiotic Stress Conditions Tayyaba Hussain, Muhammad Usmaan, Muhammad Numan, Aamir Abdullah Khan, Faiza Abbas, and Alvina Gul Abstract Agriculture is the fundamental element among humans which leads to crop productivity and stability of the environment. Cutting edge techniques open doors to new dimensions of the research into soil microbiomes to find new ways to explore worthy resources. Microbiome explicitly has an uplifting role in host inter- action. Mycorrhizal associations in particular have a remarkable innovation toward agricultural sustainability. Among them, arbuscular mycorrhizal fungi are surged above all other associations of host–microbiome interaction. Although it primarily depends upon gene manipulation and its expression of both host and associated microbe, AMF has an imperative role in controlling the pathogenic stress and plant growth advancement, viz., synthesis of essential secondary metabolites along with vital antioxidants that have a splendid impact on promoting plant growth and making a nutrient-rich rhizosphere. AMF symbiosis ameliorates myriad biotic and abiotic stresses ranging from salinity, drought (which leads to ROS stress), nutrient scarcity and heavy metal toxification which are highly lethal to plant’s health and produc- tivity. However, there is a need to unravel the function of arbuscular mycorrhizal fungi and peculiarities to overcome combine stresses. An eco-friendly approach is the need of time, such as the use of arbuscular mycorrhizal fungi, for better yield and T. Hussain Department of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan M. Usmaan Central Cotton Research Institute CCRI Multan, Multan, Pakistan M. Numan Laboratory of Molecular Biology and Biotechnology, University of North Carolina, Chapel Hill, USA A. A. Khan Department of Plant Biology and Ecology, Nankai University Tianjin, Tianjin, China F. Abbas Department of Biochemistry, Quaid-i-Azam University, Islamabad, Pakistan A. Gul (B ) Atta-ur-Rahman School of Applied Biosciences, National University of Sciences and Technology, Islamabad, Pakistan © Springer Nature Switzerland AG 2021 A. N. Yadav (ed.), Soil Microbiomes for Sustainable Agriculture, Sustainable Development and Biodiversity 27, https://doi.org/10.1007/978-3-030-73507-4_16 503