An integrated molecular linkage map of olive (Olea europaea L.) was constructed based on randomly amplified polymorphic DNA (RAPD), sequence characterized amplified region (SCAR), and microsatellite markers using the pseudo-testcross strategy. A mapping population of 104 individuals was generated from an F1 full-sib family of a crossbetween 'Frantoio' and 'Kalamata'. The hybridity of the mapping population was confirmed by genetic similarity and nonmetric multidimensional scaling. Twenty-three linkage groups were mapped for 'Kalamata', covering 759 cM of the genome with 89 loci and an average distance between loci of 11.5 cM. Twenty-seven linkage groups were mapped for 'Frantoio', covering 798 cM of the genome with 92 loci and an average distance between loci of 12.3 cM. For the integrated map, 15 linkage groups covered 879 cM of the genome with 101 loci and an average distance between loci of 10.2 cM. The size of the genomic DNA was estimated to be around 3000 cM. A sequence characterized amplified region marker linked to olive peacock disease resistance was mapped to linkage group 2 of the integrated map. Thesemaps will be the starting point for studies on the structure, evolution, and function of the olive genome. When the mapping progeny pass through their juvenile phase and assume their adult characters, mapping morphological markers and identification of quantitative trait loci for adaptive traits will be the primary targets.

The olive research program at the University of Adelaide is focused on the selection of improved olive cultivars. Superior selections have been obtained from populations of feral olives that have escaped from cultivation and now grow wild throughout the southern areas of Australia. Several trees have been deemed 'superior' based on oil yield and quality data obtained by Soxhelt extraction, gas chromatography and organoleptic assessment. Techniques developed for analysing new selections will also be used to provide quality assurance to the Australian olive industry.Cultivar identification of Australian and international accessions is a routine practice using DNA fingerprinting by random amplified polymorphic DNA (RAPID) analysis.A genetic marker linked to peacock spot disease resistance was identified using bulked segregant analysis and a linkage map for olive has been generated that will be used to locate further molecular markers linked to agronomic traits. These markers will be used on new selections to make predictions about their performance under long-term cultivation. We have also investigated the degree of cross- and self-incompatibility between the cultivars Frantoio, Manzanillo, Kalamata, Pendolino and Picual, using a 5 x 5 diallel cross.