Soils into which crop plants root and from which they obtain essential minerals and water contain huge arrays of microbes. Many have highly beneficial effects on crop growth and productivity, others are pathogens causing diseases and losses to yield and quality, a few microbes offer protection from these pathogenic forms and others have little or no effect. These intimate and often complex inter-relationships are being explored with increasing success providing exciting opportunities for increasing crop yields and quality in sustainable harmony with the populations of beneficial soil microbes and to the detriment of pathogens. This book explores current knowledge for each of these aspects of soil microbiology and indicates where future progress is most likely to aid in increasing crop productivity by means which are environmentally benign and beneficial.Advanced first degree, post-graduate students, post-doctoral researchers, lecturers, research-leaders, consultants, advisors, crop practitioners and policy makers involved with crop agronomy, biological control, plant pathology, plant breeding, agriculture, soil science, environmental interactions and conservation, and others requiring up to date knowledge of the impact of soil microbiology on sustainable crop production will find this book invaluable.