Spatial and temporal genetic variation in Ethiopian barley (Hordeum vulgare L.) landraces as revealed by simple sequence repeat (SSR) markers

Ethiopia is a center of diversity for barley (Hordeum vulgare L.) and it is grown across different agro-ecologies of the country. Unraveling population structure and gene flow status on temporal scales assists an evaluation of the consequences of physical, demographic as well as overall environmental changes on the stability and persistence of populations. Here, we examine spatial and temporal genetic variation within and among barley landrace samples collected over a period of four decades (1976-2017), using simple sequence repeat (SSR) markers. Our objective was to evaluate spatial and temporal changes in barley population connectivity associated with the closure of geographic origin and time periods. Low to strong genetic diversity was observed among the landraces and STRUCTURE, Neighbour joining tree and Discriminant Analysis of Principal Component analysis revealed three clusters. The cluster analysis revealed a close relationship between landraces along geographic proximity with g...