Differentiation among barley landrace populations from the Near East

Abstract

The structure of variation in 67 barley landraces from Syria and Jordan was investigated by using various morphological and developmental traits measured on spike progenies from the landraces grown in a favorable environment in Syria. Factor analysis was used to identify trait complexes that accounted for major proportions of the total variation among landrace populations.

Subsequently, the landraces were clustered into nine distinct groups based on their similarity for all traits. Each group showed a close association to specific geographic or environmental factors, indicating that adaptive processes also are operating in current agricultural systems. These results show the usefulness of thoroughly describing the locations where germplasm accessions originate.

Finally, I investigated what proportion of the quantitative variation among landraces was due to differences in plant type. Populations were grouped according to their similarity for qualitatively inherited morphological traits. Subsequent analyses of variance on quantitatively inherited traits showed that this type of classification was as effective as geographic grouping in distributing the variance among and within groups. This result suggests that germplasm collections can be arranged according to either geographic information or morphologic similarity. Practical implications for agronomic evaluation and utilization of germplasm collections are discussed.