Whole-genome analysis with SNPs from BOPA1 shows clearly defined groupings of Western Mediterranean, Ethiopian, and Fertile Crescent barleys

Abstract

The discovery of Hordeum spontaneum C. Koch, a wild ancestor of cultivated barley, in Morocco in 1978 led to the proposal of a multicentric origin for this crop, as an alternative to the widely accepted theory of a single centre of domestication in the Fertile Crescent. Since this discovery, we have tested this hypothesis using the most advanced genetic techniques available at the time, from CM-proteins to RFLP and DNA-chloroplast markers. Nowadays, the availability of single nucleotide polymorphism (SNP) markers that are spread densely over the barley genome provides us with another powerful tool to give further support for the above. We have used 1,536 SNPs from the Barley Oligo Pool Assay 1 (BOPA1) of Illumina to characterize 107 wild and cultivated barley accessions from the Western Mediterranean, Fertile Crescent, Ethiopia, and Tibet. The results have confirmed that each location of the above-mentioned germplasm groups clusters separately. Analysis of molecular variance enabled us to focus on the chromosomal regions and loci that differentiated these groups of barley germplasm. Some of these regions contain vernalization and photoperiod response genes, some of the so-called domestication genes, as well as the most important quantitative trait locus for flowering time in the Mediterranean region. We have combined these results with other genetic evidence, and interpreted them in the framework of current theories on the onset of the Neolithic revolution in the Mediterranean region, to conclude that neither Ethiopia nor the Western Mediterranean can be ruled out as centres of barley domestication, together with the Fertile Crescent.

The USDA Barley Core Collection: Genetic Diversity, Population Structure, and Potential for Genome-Wide Association Studies

“…Subpopulation 5, which consisted primarily of Eritrean and Ethiopian landraces, was quite distinct from other African and Asian accessions and included both two-row and six-row types and an intermediate type of labile barley, exclusive to this part of Africa, whose main feature is a different number of grains at each rachis node [54], [55]. The genetic distinctiveness of barley germplasm from the Horn of Africa has been reported previously [56], [57]. Some accessions from Morocco and all the accessions from Bolivia were included in subpopulation 5.…”

Fine mapping of the Rrs1 resistance locus against scald in two large populations derived from Spanish barley landraces

“…The evaluation of both SBCC parents revealed that they present a virulence pattern close to the resistance traditionally described as Rh4 (Graner and Tekauz 1996), later renamed by Bjørnstad et al (2002) as Rrs1 Rh4 , to indicate that it belongs to the Rrs1 locus. This resistance seems typical of accessions originating in North Africa or the Western Mediterranean region: CIho 3515 is Spanish, Osiris and Malebo (parent of Yerong) from Algeria and La Mesita is from Egypt, along one of the possible paths of expansion of barley from the Fertile Crescent towards the West (Baba et al, 2011;Igartua et al 2013). Therefore, it may have evolved in response to pathotypes prevalent in that region.…”

High‐density molecular characterization and association mapping in Ethiopian durum wheat landraces reveals high diversity and potential for wheat breeding

“…More recent studies confirmed the uniqueness of Ethiopian landraces in varying degrees (Alamerew et al ., ; Haile et al ., ; Teklu et al ., ), although using smaller panels and reduced genotyping density. This degree of differentiation seems to be a common feature of Ethiopian crops and is reported on barley as well (Igartua et al ., ). The most significant PC in our PCA clearly separates improved wheat lines and Mediterranean material from landraces (Figure a).…”