Yamnomics · Phylogenomics, evolution, biogeography and key traits for breeders in yams (Dioscorea, Dioscoreaceae)

Phylogenomics, evolution, biogeography and key traits for breeders in yams (Dioscorea, Dioscoreaceae)

Biodiversity conservation has become a priority concern for both science and society due to its key role in driving human wellbeing. The increased focus on understanding biodiversity and its sustainable use has evolved concurrently with new genomic (next-generation sequencing, NGS) and bioinformatic techniques that have revolutionized the availability of DNA sequence data for comparative biodiversity studies and lead to the emergence of Phylogenomics, in which evolutionary relationships are recovered based on comparative analyses of genome-scale data. The underground organs make some species of Dioscorea essential economic sources as crops or for pharmacological purposes. Dioscorea contains 625 species distributed primarily in the tropics but with representation in temperate regions. Various Dioscorea species are critical carbohydrate and nutrient sources in many tropical regions due to their starch-rich annual tubers. Two crops, the guinea and winged yams, feed over 100 million people in Africa alone, with an annual global production of 68 MT. Its economic importance is complemented by other species which accumulate secondary steroidal compounds of pharmacological interest, and potentially for new applications like cosmetics or biofuel. Yams are resilient plants adapted for seasonal tropical climates whose diversity holds considerable potential for coping with environmental instability and have considerable untapped potential to develop human livelihoods especially among those living in the greatest poverty. Traits of interest include the mechanisms of twining direction and dwarfism (in order to avoid the need for staking cultivated yams); sex expression, flowering and incompatibility to facilitate crossing breeding lines (yams are a clonal crop and poor flowerers); the pathways that led to the synthesis of key economic secondary metabolites; and fungal (especially anthracnose)/virus disease resistance. Identifying the crop wild relatives (CWR) is essential for crop breeding, because CWR can offer genetically similar pools and their traits can be incorporated into crops. Orphan crops like yams have remained little studied at a worldwide scale, despite millions of people in less economically developed regions relying on them. The scale of molecular resources for yams to support fundamental and applied science supporting enhanced exploitation are far below those available for more mainstream crops. The main objective of YAMNOMICS was investigating the evolutionary relationships and biogeographical patterns of the genus Dioscorea based on a richly sampled NGS-based phylogenetic tree.

Data: CORDIS, © European Union