Exploring and mapping genetic variation in wild barley

Wild barley represents an important genetic resource for cultivated barley, which has a narrowed gene pool due to intensive breeding. Therefore, it is imperative to study the genetics of different traits in wild barley, if it is to be used for cultivar improvement. This thesis describes studies of different aspects of diversity, as well as linkage, QTL and association mapping in wild barley. The natural populations that were studied were collected in environmentally diverseIsrael. Using a cross between genotypes from contrasting habitats, a linkage map was produced. Due to unexpectedly high heterozygosity of one of the parents the map covered approximately 45% of the barley genome. This map was subsequently utilised in all other studies in this thesis. Genetic diversity was estimated within and between 21 populations. This was correlated with phenotypic and environmental diversities of the same populations. Genetic diversitywasloosely connected with environmental diversity. In general, phenotypic diversity did not correlate with either one. Some markers were ecotype-specific; some of these were mapped and correlated significantly not only with environmental but also with phenotypic traits. Using the same populations, correlations between mapped markers and phenotypic traits were calculated. The significant associations were then compared with QTL found in an earlier study. Many of these associations mapped to the same regions as the QTL and therefore these two approaches of mapping traits complemented each other. Lastly, the map was used to locate QTL for dormancy in wild barley. Five QTL were found of which threemapto regions where dormancy QTL has been found earlier in cultivated barley. For further research, another cross should be made to produce a map with larger coverage of the genome. The results of this thesis add to the characterisation of the diverse wild barley populations fromIsrael, which is important to the future improvement of cultivated barley.