Pear Genetic Resources and Utilization

The “Pear” chapter includes details on the classification, domestication, dispersal, and geographic distribution of the different wild pear species that can be found all over the world. This chapter also emphasizes the value of genetic resource preservation and the application of these resources to various breeding projects aimed at crop development. Pear-breeding programs all over the world have always placed a strong focus on enhancing the traits of the tree and the fruit, adding resistance to biotic and abiotic stress factors, and enhancing the unique characteristics of a small number of cultivars. After a discussion of different breeding methods, a section on various pear-breeding issues has been added (introduction, selection, seedling screening, hybridization, and non-traditional techniques like embryo culture, pollen culture, and mutagenesis). Through various improvements in breeding methods and genomics, traits are incorporated into new genotypes. With an emphasis on gene mapping and the development of markers linked to monogenic and polygenic traits, numerous molecular breeding methods have been described in great detail. The chapter also focuses on the underutilized potential of genetic engineering as well as how functional genes affect various fruit characteristics. Other topics covered include different strategies being used in the aftermath of pear genome sequencing.