EVALUATION AND DEVELOPMENT POTENTIAL OF OLIVE CULTIVARS IN SOUTH AFRICA

Various Olea spp. are indigenous in southern Africa, and although they have no commercial value as fruit crops, some are utilised for wood. The local olive industry, however, owes its existence to the occurrence of Olea europaea subsp. Africana, which was utilised as a rootstock for commercial cultivars before propagation by means of semi-hardwood cuttings became standard procedure in the middle of the previous century. South African olive production, of which table olives make up a significant segment, is entirely dependent on cultivars originating in Italy (‘Frantoio’), Greece (‘Kalamata’), Spain (‘Manzanilla’), Tunisia (‘Barouni’) and the USA (‘Mission’). These cultivars were selected by the industry over time from a wide range of imports. All of them however have shortcomings and so improvements are continually sought to remain profitable, to keep pace with changing technology and the demands of the market. A concerted effort by the industry to improve the range of cultivars entailed initiating a research programme where numerous cultivars recommended by overseas experts were imported and evaluated on an on-going basis from 1977 to 2002. Most of these and subsequent imports proved to be poorly adaptable to local conditions. As a result of new techniques developed in Spain and Israel, the breeding of new olive cultivars became a viable option, and a small breeding and selection program was initiated locally. One table olive selection has so far been released to the industry and numerous promising candidates, adapted to modern orchard practices under South African conditions, are being evaluated currently. Although some plant material has recently been exchanged with overseas institutions, the value of the indigenous gene pool remains unexploited.