Development of DArT markers in olive (Olea europaea L.) and usefulness in variability studies and genome mapping

The present study reports the setting up of Diversity Arrays Technology (DArT) markers in olive (Oleo europaea L.). Two genomic representations were generated using the Pstl/Taql combination. A first one was aimed to cover the variability available at the World Olive Germplasm Bank (WOGB) and it was based on DNA from 87 olive cultivars carefully selected from the WOGB to represent the olive variability. The second one was obtained from DNA of the parents of a mapping population, 'Picual' and 'Arbequina', and was used to increase the number of markers segregating within them. A total of 2031 and 1630 markers were used for diversity and mapping analyses, respectively to test the utility of DArT markers in olive. A set of 62 cultivars was genotyped with olive-specific DArT markers. A dendrogram was constructed confirming the relationships among olive cultivars reported in previous works. Besides, DArT markers permitted the unambiguous discrimination of all 62 genotypes confirming thus their utility for identification studies, an important issue for management of germplasm collections. DArT markers also allowed the construction of a genetic map of olive using the population derived from the cross 'Picual' X 'Arbequina' and the pseudo-testcross mapping strategy. This map will be used as a framework map to add new markers derived from olive sequencing originating from the project OLEAGEN. In conclusion, olive-specific DArT markers will enhance identification and genetic studies in olive given their high throughput and low cost per data. (c) 2011 Elsevier B.V. All rights reserved.