This book marks the centenary of the rediscovery of Mendel's laws of biological inheritance, which have had their greatest economic impact in the rapid development of the science of plant breeding. It documents the development of methods of plant breeding over a hundred year period beginning with simple hybridization and selection techniques moving to more complex procedures following advances in quantitative and molecular genetics. The concepts and methodology of plant breeding with their underpinning of the advances in classical genetics, molecular biology and biotechnology have received special attention. Plant breeding in the 21st century will be marked with an increasing integration of the classical methods with the newer techniques of modern biotechnology. This book points to the kind of integration, which will be taking place, opening up altogether new possibilities for increasing economic yields through enhancement of harvest index, combined with greater resistance to biotic and abiotic stresses. It starts with papers which revisit some of the landmark discoveries in genetics and plant breeding in the last hundred years and goes on to cover a wide range of topics which should be of interest to students, teachers and practitioners of plant breeding. Some of the topics covered include: hybrid breeding and molecular concepts of heterosis; recurrent selection methods and population improvement strategies; quantitative trait loci in crop improvement; genotype environment interaction and mating designs; host-pathogen interactions and durable resistance; breeding for wider adaptability; plant type concept and applications; mutation breeding; chromosome manipulations and molecular cytogenetics; genomics, transgenics and molecular markers; and, plant genetic resources and IPR.