Sexual compatibility and floral biology of some olive cultivars

Pollen tube observation was used to assess the self- and cross-incompatibility of the olive (Olea europaea L.) cultivars 'Frantoio', 'Koroneiki' and 'Kalamata'. The pistils were harvested 1 week after hand pollination and stained with 0.1% aniline blue. The styles and ovules were separated, mounted in 80% glycerol and observed under a fluorescence microscope. All the cultivars studied were self-incompatible. 'Frantoio' (as a host) was incompatible with 'Koroneiki' and 'Barnea' but partially compatible with 'Mission'. 'Koroneiki' (as a host) was incompatible with 'Barnea' but partially compatible with 'Frantoio' and 'Mission'. 'Kalamata' (as a host) was compatible with 'Barnea', incompatible with 'Mission' and 'Koroneiki' in 2004, but partially compatible with them in 2005. The effects of shoot orientation and inflorescence location on inflorescence characteristics were also studied. For each cultivar, inflorescence characteristics in three sections of shoots (top, middle and base) and four sides of the three selected trees (north, south, east and west) were recorded. The statistical analysis showed that basal inflorescences were shorter and with fewer flowers but with the same percentage of perfect flowers. Shoot orientation did not have any influence on these characteristics in any of the cultivars.