A Multifaceted Overview of Apple Tree Domestication

The evolutionary history of the apple tree is complex because of the wide geographic distribution of wild species, ease of hybridization, and different modes of propagation. The lack of tools to distinguish between cultivated and wild apples has hampered the reconstruction of the evolutionary history of apple trees. Multidisciplinary approaches have allowed a better characterization of the ecology of the wild relatives of apple, and have provided interesting information about the use and cultivation history of the apple. The lack of secure archeological and even modern wild apple samples at a population level across comprehensive spatial and temporal scales remains an important limitation. The apple is an iconic tree and a major fruit crop worldwide. It is also a model species for the study of the evolutionary processes and genomic basis underlying the domestication of clonally propagated perennial crops. Multidisciplinary approaches from across Eurasia have documented the pace and process of cultivation of this remarkable crop. While population genetics and genomics have revealed the overall domestication history of apple across Eurasia, untangling the evolutionary processes involved, archeobotany has helped to document the transition from gathering and using apples to the practice of cultivation. Further studies integrating archeogenetic and archeogenomic approaches will bring new insights about key traits involved in apple domestication. Such knowledge has potential to boost innovation in present-day apple breeding. The apple is an iconic tree and a major fruit crop worldwide. It is also a model species for the study of the evolutionary processes and genomic basis underlying the domestication of clonally propagated perennial crops. Multidisciplinary approaches from across Eurasia have documented the pace and process of cultivation of this remarkable crop. While population genetics and genomics have revealed the overall domestication history of apple across Eurasia, untangling the evolutionary processes involved, archeobotany has helped to document the transition from gathering and using apples to the practice of cultivation. Further studies integrating archeogenetic and archeogenomic approaches will bring new insights about key traits involved in apple domestication. Such knowledge has potential to boost innovation in present-day apple breeding. the study of plant remains (seeds, fruits, wood, leaves, pollen, etc.) found in archeological deposits with the aim of reconstructing the paleoenvironment and the management of plant resources (including the domestication of wild plants), their uses, and the waste-disposal practices of ancient societies. research fields that use the genetic information gathered from archeological plant or animal remains (ancient DNA, aDNA) to address questions about the evolution, domestication, and history of use and cultivation of plants and animals (e.g., [33.Nathan W. et al.Ancient DNA reveals the timing and persistence of organellar genetic bottlenecks over 3,000 years of sunflower domestication and improvement.Evol. Appl. 2019; 12: 38-53Crossref PubMed Scopus (13) Google Scholar, 80.Besnard G. et al.On the origins and domestication of the olive: a review and perspectives.Ann. 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Genet. 2015; 16: 395-408Crossref PubMed Scopus (117) Google Scholar]). selection regimes that result in increased genetic diversity relative to neutral expectations in populations of living organisms. wild apple species that usually blossom profusely and produce small, acidic fruits [3.Cornille A. et al.The domestication and evolutionary ecology of apples.Trends Genet. 2014; 30: 57-65Abstract Full Text Full Text PDF PubMed Scopus (135) Google Scholar]. The word crab comes from the Old English crabbe, meaning 'bitter' or 'sharp tasting'. Many crabapples are cultivated as ornamental trees. In Western Europe the term crabapple is often used to refer to Malus sylvestris (the European crabapple), in the Caucasus to M. orientalis (the Caucasian crabapple) and, in Siberia, to M. baccata (the Siberian crabapple). The native North American crabapples are M. fusca, M. coronaria, M. angustifolia, and M. ioensis. Malus sieversii, the main progenitor of the cultivated apple, is not usually referred to as a 'crabapple'. the only domesticated species in the genus Malus, here called Malus domestica. Malus domestica is often referred to as Malus × domestica, the '×' indicating a hybrid origin. However, from what we know so far, the cultivated apple did not originate from a hybrid speciation event. The cultivated apple originated from the Central Asian wild apple M. sieversii and was later introgressed by other wild species present along the ancient Silk Road trading routes. We therefore prefer the name M. domestica. a technique of vegetative propagation wherein tissues of two plants are intentionally joined and are allowed to grow together. The upper part of the combined plant (which contributes the aerial parts and produces fruit) is called the scion and the lower part (which provides the roots) is called the rootstock. the transfer of genomic regions from one species into the gene pool of another species through an initial hybridization event followed by repeated backcrosses. agents that determine the presence and preservation quality of items found in sedimentary deposits. a laboratory technique used to process sediment samples from archeological deposits using the principle of density where a light fraction and a heavy fraction are separated inside the flotation tank. Both fractions are usually dried after the separation process is finished. When waterlogged sediments are processed, the fractions must be stored in water at a temperature of ~4°C.