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Original multidisciplinary research hereby clarifies the complex geodomestication pathways that generated the vast range of banana cultivars (cvs). Genetic analyses identify the wild ancestors of modern-day cvs and elucidate several key stages of domestication for different cv groups. Archaeology and linguistics shed light on the historical roles of people in the movement and cultivation of bananas from New Guinea to West Africa during the Holocene. The historical reconstruction of domestication processes is essential for breeding programs seeking to diversify and improve banana cvs for the future.plant genetics | historical linguistics | archaeobotany | diploid banana cultivars | triploid banana cultivars N ew multidisciplinary findings from archaeology, genetics, and linguistics clarify the complex geodomestication pathways-the geographical configurations of hybridization and dispersalthat generated the range of modern banana cultivars (cvs). Although recent molecular research, combined with the outcomes of previous genetic studies, elucidates major stages of banana domestication, such as the generation of edible diploids and triploids, it sheds only partial light on the historical and sociospatial contexts of domestication. The geographic distributions of genotypes involved in banana domestication require human translocations of plants, most likely under vegetative forms of cultivation, across vast regions. Linguistic analyses of (traditional) local terms for bananas reveal several striking regional-scale correspondences between genetic and linguistic patterns. These multidisciplinary findings enable the relative dating of the principal events in banana geodomestication and situate banana cultivation within broader sociospatial contexts. Archaeological findings provide a timeline to anchor and calibrate the relative chronology.

Deciphering the diversity of the banana complex needs a joint characterization and analysis of the original wild species and their relatives, primitive diploid forms and triploid derived varieties. Sexuality, the primary source of diversity, is strongly disrupted in the cultivated varieties (sterility, parthenocarpy and vegetative propagation) by human selection of vegetatively maintained punctuated mutations. Many biological tools are available for characterizing this diversity, each one illustrating some peculiar facets, and we show that their joint analysis enables an evolutionary reading of this diversity. We propose various scenarios regarding the structure of wild species, on the domestication of the edible diploids from hybrids between wild forms, on the direct ancestry of triploids from cultivated diploids, and on the ancient migrations dispersing cultivated forms around the world. The comparison with data from archaeology, linguistics and human genetics will enable the validation, refinement and dating of the proposed domestication process.

In banana, the maternal transmission of chloroplast DNA and paternal transmission of the mitochondrial DNA provides an exceptional opportunity for studying the maternal and paternal lineage of clones. In the present study, RFLP combined with hybridization of heterologous mitochondrial and chloroplastic probes have been used to characterize 71 wild accessions and 131 diploid and 103 triploid cultivated clones. In additon to Musa acuminata and Musa balbisiana, other species from the four Musa sections were studied to investigate their contribution to the origin of cultivated bananas. These molecular analyses enable the classification of the Musa complex to be discussed. Results ascertain relationships among and between the wild accessions and the mono- and interspecific diploid and triploid bananas, particularly for the acuminata genome. Parthenocarpic varieties are shown to be linked to M. acuminata banksii and M. acuminata errans, thus suggesting that the first center of domestication was in the Philippines - New Guinea area.

Background and AimsThe production of triploid banana and plantain (Musa spp.) cultivars with improved characteristics (e.g. greater disease resistance or higher yield), while still preserving the main features of current popular cultivars (e.g. taste and cooking quality), remains a major challenge for Musa breeders. In this regard, breeders require a sound knowledge of the lineage of the current sterile triploid cultivars, to select diploid parents that are able to transmit desirable traits, together with a breeding strategy ensuring final triploidization and sterility. Highly polymorphic single sequence repeats (SSRs) are valuable markers for investigating phylogenetic relationships.MethodsHere, the allelic distribution of each of 22 SSR loci across 561 Musa accessions is analysed.Key Results and ConclusionsWe determine the closest diploid progenitors of the triploid ‘Cavendish’ and ‘Gros Michel’ subgroups, valuable information for breeding programmes. Nevertheless, in establishing the likely monoclonal origin of the main edible triploid banana subgroups (i.e. ‘Cavendish’, ‘Plantain’ and ‘Mutika-Lujugira’), we postulated that the huge phenotypic diversity observed within these subgroups did not result from gamete recombination, but rather from epigenetic regulations. This emphasizes the need to investigate the regulatory mechanisms of genome expression on a unique model in the plant kingdom. We also propose experimental standards to compare additional and independent genotyping data for reference.