Variability of first flower to ground distance in olive seedlings and its relationship with the length of the juvenile period and the parent genotype

• Published in: Scientia horticulturae 2011-07, Vol.129 (4), p.747-751
• Main Authors: Suárez, M.P., Casanova, L., Jiménez, R., Morales-Sillero, A., Ordovás, J., Rallo, P.
• Format: Article
• Language: English
• Subjects: adulthood; Agronomy. Soil science and plant productions; Biological and medical sciences; branches; Breeding; canopy; cultivars; First flowering; flowering; flowers; Fundamental and applied biological sciences. Psychology; genotype; Juvenility; Juvenility cone; Olea europaea; olives; parents; progeny; seedlings; seeds; trees; woody plants
• ISSN: 0304-4238; 1879-1018
• DOI: 10.1016/j.scienta.2011.05.033

► We studied the distance of the first flower from the ground in olive seedlings. ► The cone-shape transition from juvenile to adult phases is confirmed. ► Length of the juvenile period and parent genotype influence first flower position. ► Parent genotype influences irrespective of being used as female or male parent. ► First flower to ground distance may not be constant within the olive species. During development, most woody plants that develop from seeds undergo a juvenile phase before transitioning to adulthood. The first flowering indicates the end of the juvenile period and can be used as a marker to discriminate between phases. In this study we analyzed the distance of the first flower from the ground, measured along the trunk and supportive branches, in 385 olive seedlings coming from eight different crosses. We found that for tree canopy base heights of 1.5 and 1.0 m the average distance at which the first flower appeared was 2.41 or 2.07 m, respectively. Moreover, we observed for the first time that the first flower to ground distance was significantly correlated with the juvenile period length and the olive seedling parent genotype. In fact, a particular cultivar demonstrated a consistent influence on the location of the progeny first flower, irrespective of being used as female or male parent. This implies that the first flower to ground distance may not be constant within the olive species. A juvenile cone and its measurement was recently described in olive trees. In this study we similarly find a negative relationship between branch insertion height and the distance from the branch insertion in the trunk to the nearest inflorescence. This observation confirms the cone-shape transition from juvenile to adult phases, although it implies that the specific characteristics of the juvenile cone ultimately depend on the length of the juvenile period. Trees with longer juvenile periods tended to flower for the first time at a greater total distance from the ground. This increase in the first flower to ground distance was due to an increase in the distance from the branch insertion in the trunk to the nearest inflorescence on the branch, whereas the branch insertion height decreased.