Canopy growth and architecture of five olive cultivars for high-density orchards

In the last decades, olive-growing systems were subjected to an intensification of the planting density (up to the super-high density olive orchards with more than 1,000 trees ha(-1)) in order to obtain a hedgerow, increase mechanization and reduce cultivation costs. The requested characteristics of the olive varieties to fit with these models are a whole tree compact growth habit, high canopy density, slow canopy growth and early and consistent fruit production. The suitability of the different cultivars to the high-density plantations requires more detailed investigation about the vegetative-reproductive pattern within the canopies. The study of the vegetative growth and the architectural characteristics of the canopy can supply helpful information about the most suitable planting density for each olive cultivar and the best cultural practices and fitting mechanization levels. The vegetative growth and canopy architecture of 'Arbequina', 'Biancolilla', 'Coratina', 'Leccio del Corno' and 'Maurino' cultivars were assessed in a high-density (1,250 trees ha(-1)) olive orchard. The suitability/unsuitability of the canopy shape to the hedgerow system was evaluated. Tree height, canopy dimensions, trunk diameter at different heights from the ground, branch intersection height along the trunk, basal diameter, length and position in the 3D dimension of the primary branches were measured when trees were 2 years old. On sampled primary branches, shoot spatial organization and density along the axis were also studied. Results showed a different vegetative growth behavior and architecture of the canopy and primary branch of the assessed cultivars suggesting the belonging to distinctive groups and thus suitability to planting densities.