%O We are grateful for excellent technical assistance by K. Luxa and E. Luley. This work was supported by the Max Planck Society, the German Plant Genome Research Initiative of the Federal Ministry of Education and Research (BMBF), by grants from the DFG SPP1530 (“Flowering time control: from natural variation to crop improvement”), and by grants to ICARDA from the German Federal Ministry of Economic Cooperation and Development (BMZ, Bonn, Germany), the Generation Challenge Program and the Global Centre of Excellence Program, Tottori University, Japan. %K Barley, Dryland conditions, Syria %A J A Rollins %A B Drosse %A M A Mulki %A S Grando %A M Baum %A M Singh %A S Ceccarelli %A M von Korff %I Springer Verlag %V 126 %L icrisat8383 %J Theoretical and Applied Genetics %N 11 %P 2803-2824 %R 10.1007/s00122-013-2173-y %D 2013 %X The objective of the present study was to identify QTL influencing agronomic performance in rain-fed Mediterranean environments in a recombinant inbred line (RIL) population, ARKE derived from the Syrian barley landrace, Arta and the Australian feed cultivar, Keel. The population was field tested for agronomic performance at two locations in Syria for 4 years with two sowing dates, in autumn and winter. Genotypic variability in yield of the RIL population was mainly affected by year-to-year variation presumably caused by inter-annual differences in rainfall distribution. The spring growth habit and early flowering inherited from the Australian cultivar Keel increased plant height and biomass and improved yield stability in Syrian environments. QTL for yield and biomass coincided with the map location of flowering time genes, in particular the vernalisation genes Vrn-H1 and Vrn-H2. In marginal environments with terminal drought, the Vrn-H1 allele inherited from Keel improved final biomass and yield. Under changing climate conditions, such as shorter winters, reduced rainfall, and early summer drought, spring barley might thus outperform the traditional vernalisation-sensitive Syrian landraces. We present the ARKE population as a valuable genetic resource to further elucidate the genetics of drought adaptation of barley in the field. %T Variation at the vernalisation genes Vrn-H1 and Vrn-H2 determines growth and yield stability in barley (Hordeum vulgare) grown under dryland conditions in Syria