The Rosaceae Family is represented by approximately 3,000 species of diverse plants, primarily con?ned to temperate climates. The family has a rich variety of architectural forms and contains herbaceous, tree and shrub species. Many family members are readily recognizable because of their edible seasonal fruits that are prized for their unique ?avors, colors and nutritious properties (e.g. apple, str- berry, raspberry, pear, cherry, plum, apricot, pear), as well as familiar ornamentals (e.g. roses) and nuts (e.g. almonds). Today's rosaceous cultivars have been derived from centuries of careful sel- tion and breeding, using a palette of some of evolution's most curious creations. The careful sculpting that has transformed the germplasm was not trivial, as several of the most coveted fruit species maintain complicated genomes-in some cases among the most complex of cultivated plants (e.g. strawberry). Other species in the family are represented by large perennial tree crops that exhibit substantial juven- ity phases, posing a barrier to standard breeding and genetic analyses. Yet, today's superiorcultivarsfeaturerobustgrowth,substantialyieldsandresistancetocommon biotic and abiotic stresses; traits fostered by human intervention. When the hurdles to ef?cient cultivation, breeding and selection are considered, the quality and qu- tity of rosaceous plant products derived from traditional breeding techniques is little short of amazing.

For the past decade, there has been success in using conventional map-based strategies in identification and cloning of Quantitative Trait Loci (QTL) in model plant species including tomato and Arabidopsis. These quantitative traits are generally the products of many loci with varying degrees of effect upon the observed phenotypes. Recently, a new approach to genetic mapping has emerged called association mapping. This new technique takes into account the thousands of genes to evaluate for QTL effect and is a more efficient approach that does not require generation of segregating populations/large numbers of progeny. As it can utilize all of the historic recombination events in a diverse population of individuals it can generate higher resolution genetic maps and, is needed to complement current map based cloning methods. Association Mapping in Plants provides both basic and advanced understanding of association mapping and an awareness of population genomics tools to facilitate mapping and identification of the underlying causes of quantitative trait variation in plants. It acts as a useful review of the marker technology, the statistical methodology, and the progress to date. association studies.

The Rosaceae Family is represented by approximately 3,000 species of diverse plants, primarily con?ned to temperate climates. The family has a rich variety of architectural forms and contains herbaceous, tree and shrub species. Many family members are readily recognizable because of their edible seasonal fruits that are prized for their unique ?avors, colors and nutritious properties (e.g. apple, str- berry, raspberry, pear, cherry, plum, apricot, pear), as well as familiar ornamentals (e.g. roses) and nuts (e.g. almonds). Today's rosaceous cultivars have been derived from centuries of careful sel- tion and breeding, using a palette of some of evolution's most curious creations. The careful sculpting that has transformed the germplasm was not trivial, as several of the most coveted fruit species maintain complicated genomes-in some cases among the most complex of cultivated plants (e.g. strawberry). Other species in the family are represented by large perennial tree crops that exhibit substantial juven- ity phases, posing a barrier to standard breeding and genetic analyses. Yet, today's superiorcultivarsfeaturerobustgrowth,substantialyieldsandresistancetocommon biotic and abiotic stresses; traits fostered by human intervention. When the hurdles to ef?cient cultivation, breeding and selection are considered, the quality and qu- tity of rosaceous plant products derived from traditional breeding techniques is little short of amazing.