Book excerpt: Disease Resistance in Plants, Second Edition, looks at genetic, epidemiologic, biochemical, and biometric principles for developing new cultivars possessing genetic resistance to diseases. It examines the nature of disease resistance and resistance genes, and it highlights the importance of stabilizing selection, sugar, biotrophy, and necrotrophy to obtain the greatest possible yields. Organized into 17 chapters, this volume begins with an overview of disease resistance in plants and the ways to develop disease-resistant variants. It then discusses unspecific resistance; the resistance gene paradox; susceptibility and resistance within narrow host taxa; phenotypic variation and gene numbers in host plants; discontinuous variation and cytoplasmic inheritance; and experimental difficulties in partitioning variance. The reader is also introduced to epistasis and the structure of virulence in pathogens; the notion of physiological race; how the pathogen adapts to the host; mutation in the pathogen from avirulence to virulence; horizontal and vertical resistance to disease and its epidemiological effects; and the link between protein polymorphism and vertical resistance. In addition, the book discusses genes for susceptibility in the host versus genes for avirulence (or virulence) in the pathogen; sink-induced loss of resistance; high-sugar disease processes and biotrophy; slow rusting of cereal crops; plant resistance against endemic disease; and the accumulation of resistance genes in heterogeneous host populations. This book will be useful to plant pathologists and plant breeders.