This book explores microbial symbiosis, with a particular focus on soil microorganisms, highlighting their application in enhancing plant growth and yield. It addresses various types of bacterial and fungal microbes associated with symbiotic phenomena, including rhizobium symbiosis, arbuscular mycorrhizal symbiosis, ectomycorrhizal symbiosis, algal/lichen symbiosis, and Archeal symbiosis. Presenting strategies for employing a diverse range of bacterial and fungal symbioses in nutrient fortification, adaptation of plants in contaminated soils, and mitigating pathogenesis, it investigates ways of integrating diverse approaches to increase crop production under the current conventional agroecosystem. Providing insights into microbial symbioses and the challenges of adopting a plant-microbe synergistic approach towards plant health, this book is a valuable resource for researchers, graduate students and anyone in industry working on bio-fertilizers and their agricultural applications.