Comparison of Canopy Architecture of Five Olive Cultivars in a High-Density Planting System in Sicily

In a young super-high-density (SHD) olive orchard located in Aidone (EN), in the Sicily Region, Italy, the architectural features of five olive cultivars were studied, specifically Arbequina, Arbosana, Oliana (R), Giulia (R), and FS-17 (R). Surveys were conducted in November 2019 considering biometric measurements for the whole tree, the canopy, and the primary and secondary branches. The "total branching frequency", the "sectorial branching frequency", the "total branching efficiency", the "sectorial branching efficiency", and the "total relative vigour" indexes were also calculated from the previous measurements. In addition, olive yield recorded for the years 2020, 2021, and 2022 (respectively, the third, fourth, and fifth years from planting) are shown in order to provide a more exhaustive description of the features of the cultivars. Giulia (R) and Oliana (R) resulted in being more similar to Arbequina and Arbosana, presenting a compact shape of the canopy and high and regular ramification of primary and secondary branches. FS-17 (R) showed a higher expansion in canopy volume and higher vigour than the other cultivars, features that suggest it can be more susceptible to damage during mechanical harvest. Regarding the elaborated indexes, "total branching frequency" resulted in being not statistically different among the cultivars. "Sectorial branching frequency" resulted in being higher in the middle sector of the trunk height (51-100 cm) for all the tested cultivars. This study supplies helpful information about the different canopy and branch architectural characteristics of the five studied olive cultivars with respect to their suitability to high-density plantations.