Browsing by Browse by SEO 2008 "820208 Olives"

The influence of flower position on the inflorescence on opening day, gender, and petal persistence was studied in three olive cultivars: Manzanillo, Mission, and Frantoio. In each cultivar, 45 inflorescences were checked every morning from flower opening to petal fall. Perfect flowers opened mainly in the beginning of the flower opening period, and staminate flowers opened later. Flower position on the inflorescence had a highly significant effect on the opening day in all cultivars. Terminal flowers and the flowers located on the primary branches opened earlier than the flowers located on the secondary branches. Flower position had also a highly significant effect on gender in Manzanillo and Mission. In Manzanillo, the secondary branches had fewer perfect flowers than the primary branches. In Mission, the secondary branches had no perfect flowers at all. Among the primary branches, the branch arising immediately next to the terminal flower had the latest flowers to open and the lowest percent of perfect flowers. In Manzanillo, perfect flowers had significantly longer petal persistence than staminate flowers. To study flower competition within the inflorescence, the distal half of 120 inflorescences, on which the flowers tend to be perfect, in three trees of Manzanillo were removed about 1 month before full bloom. There was a highly significant effect on the percent of perfect flowers that opened on the proximal half. Flower competition may be a reason for pistil abortion in flowers located on secondary branches.

Olive ('Olea europaea' L.) is a wind-pollinated, allogamous species that is generally not considered to be self-compatible. In addition, cross-incompatibilities exist between cultivars that can result in low fruit set if compatible pollinisers are not planted nearby. In this study, microsatellite markers were used to identify 17 genotypes that were potential pollen donors in a commercial olive orchard. DNA typing with the same primers was also applied to 800 olive embryos collected from five cultivars in the grove over 2 years of study. Pollen donors for the cultivars Barnea, Corregiola, Kalamata, Koroneiki, and Mission were estimated by paternity analysis, based on the parental contribution of alleles in the genotypes of the embryos. The exclusion probability for the marker set was 0.998 and paternity was assigned on the basis of the ‘most likely method’. Different pollen donors were identified for each of the maternal cultivars indicating that cross-compatibilities and incompatibilities varied between the genotypes studied. Cross-pollination was the principal method of fertilization, as selfing was only observed in two of the embryos studied and both of these were from the cultivar Mission. This is the first report where these techniques have been applied to survey the pollination patterns in an olive grove. The results indicate that careful planning in orchard design is required for efficient pollination between olive cultivars.

Paternity analysis was used to assess the self-incompatibility of the olive ('Olea europaea' L.) cultivar 'Kalamata' and to identify some compatible pollenisers under a Mediterranean-type climate. Eight microsatellite markers were used for genotyping three 'Kalamata' mother trees, 120 embryos, and all potential pollen donors. The identified alleles were analysed using FaMoz software and showed that 'Kalamata' was highly self-incompatible. Only three 'Kalamata' embryos were assigned to 'Kalamata' self-fertilisation, even though it was the most available pollen donor. The alleles were also analysed using NTSYS-pc (version 2.02 k) software and identified 54 potential pollen donors in the study site; however, not all of them were located within the effective pollination distance of the mother trees (30 m in olive). According to the results of this study, 'Kalamata' (as a host) was compatible with 'Barnea', 'Benito', and 'Katsourela' (six 'Kalamata' embryos assigned in each) but incompatible with 'Arbequina', 'Azapa', and 'Picual' (zero 'Kalamata' embryos assigned in each). The olive growers could use some of these compatible pollenisers with 'Kalamata' to guarantee good fruit set.