Genetic Erosion and Morphological and Molecular Markers Diversity of Ethiopian Tetraploid Wheat Landraces: Implications for Conservation and Utilization (English shop)

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A better understanding of genetic diversity and its distribution is necessary not only for the effective use of genetic resources in breeding programmes, but also for the design of collecting missions and conservation projects. To this end, the diversity of Ethiopian tetraploid wheat landraces was investigated using morphological and molecular markers. For the morphological analysis, 271 accessions were examined for 13 morphological and agronomic traits. Statistical methods such as the Shannon Weaver diversity index and multivariate techniques (clustering, ordination, discriminant analysis) were applied. The results of the principal component analysis showed that the first five principal components, with eigenvalues >1, accounted for 75.42% of the total variation among all accessions. Both the cluster analysis and the scatter plot of PC1 against PC2 revealed the absence of a clear pattern of regional grouping, since accessions from different areas were distributed across many clusters. By means of discriminant analysis, the accessions could be differentiated with an average correct classification rate of 60.9%. Important variables in the discriminant analysis were days to heading and spike length. The Shannon-Weaver diversity index across all traits was 0.74. Partitioning the total phenotypic diversity into diversity between and within regions yielded values of 0.71 and 0.29, respectively. In general, phenotypic diversity showed considerable differences for each trait across different geographical regions and altitude classes.