Abstract
Plants have always been integral to human society and their (genetic) improvement has been carried out ever since humans became farmers. Breeders are seeking to alter plants in a permanent and heritable manner in order to enhance agricultural production relying on the scientific and technical advancements in molecular biology and biotechnology. Plant breeding simultaneously creates and exploits biological diversity (genetic variation), which are the main activities for plant breeders. Both plant domestication and traditional (conventional or classical) breeding depended on the natural processes and genetic potential of the species. However, innovations, such as mutation breeding, various biotechnological tools (e.g. in vitro techniques), and speed breeding, have been developed to enhance genetic gain and accelerate the breeding process. Furthermore, to improve selection, molecular markers were introduced. Strategies, such as molecular-assisted selection and genomic selection, are part of molecular (modern or nonconventional) breeding, which also includes two approaches based on genetic engineering: transgenesis and genome editing. The main characteristics of all these breeding tools — the essential assets for overcoming the agricultural challenges of modern civilization — and their relation to one another are presented in this chapter.