Olive cultivar improvement through selection and biotechnology

Abstract

The olive research program at the University of Adelaide is focussed 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 Soxhlet 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 now a routine practice using DNA fingerprinting by random amplified polymorphic DNA (RAPD) 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.