This book examines the crucial role of soil microbial communities in agroecosystems, highlighting their contributions to plant growth promotion, disease suppression, pathogen resistance, and soil remediation. Recent advances in sequencing technologies and bioinformatics have brought soil microbiome research to the forefront, emphasizing its significance for sustainable agriculture.Combining theoretical insights with practical case studies, this volume introduces diverse soil- and plant-associated microbes—including bacteria, mycorrhizal fungi, yeasts, and polyextremophilic communities—and explores their specific functions and applications in addressing major challenges in eco-friendly crop management.This book serves as an essential resource for researchers and scholars in microbiology, environmental sciences, and agriculture.