Agronomic Characteristics of Several Italian Olive Cultivars and Evaluation for High-Density Cultivation in Central Italy

Abstract

The adaptability of several Italian olive cultivars to high-density cultivation was evaluated from 2020 to 2024 in central Italy by assessing their agronomic behavior, with the aim of identifying which Italian olive cultivars can combine high productivity and suitability for intensive mechanization—through high- and very high-density planting systems—allowing biodiversity valorization. The cultivars were Borgiona, Don Carlo, FS17, Gentile di Anghiari, Gentile di Montone, Giulia, Leccio del Corno, Maurino, Moraiolo, Pendolino, Piantone di Falerone, and Piantone di Mogliano. The international cultivar Arbequina was used as a reference. The olive orchard was planted in 2015, at a tree spacing of 5 m × 2 m (1000 trees/ha). Arbequina was found to have limited vigor and high production efficiency, as reported in other works, therefore confirming its suitability for high-density and super-high-density cultivation. Some cultivars, such as Leccio del Corno, Maurino, FS17, Piantone di Mogliano, and Piantone di Falerone, had a production and yield efficiency that was not different from or even higher than Arbequina. Other cultivars found to be promising were Don Carlo and Gentile di Anghiari, which had a slightly lower productive performance than Arbequina. Overall, the results are encouraging and suggest that some of these cultivars may be suitable candidates for high- and super-high-density olive orchards. This suitability is further supported by their favorable fruit characteristics, which appear to facilitate efficient mechanical harvesting. However, additional data is necessary to enable a more comprehensive assessment of these cultivars, particularly their capacity to maintain canopy dimensions compatible with straddle harvester operation, while maintaining a stable vegetative–reproductive balance over time.

1. Introduction

In the last 30–40 years, olive oil consumption worldwide has more than doubled because of the growing popularity of the Mediterranean diet. The increase in demand has mainly occurred in countries with high income levels (e.g., Northern Europe, North America, Japan, Australia, etc.), and there is still room for further increases, as olive oil consumption worldwide only accounts for 4–5% of fat consumption [1]. The rise in consumption has been met by increased production in producing countries, favoring an increase in extra virgin olive oil production. For this, a fundamental role can be played by the renewal and expansion of olive-growing areas through the establishment of new plantings. The renewal of plantings would be particularly useful for traditional olive orchards made up of old trees that no longer respond to modern cultivation techniques and have major limitations for mechanized harvesting. New olive orchards are also important because they reduce labor requirements, which are increasingly hard to meet, especially in Western countries. Likewise, production costs are lower compared to traditional orchards, due to their higher degree of mechanization.

Currently, three planting models are used, namely, intensive, super-intensive, and high-density [2,3].

Intensive olive orchards, a well-known planting model, are characterized by planting densities varying from 200 to 400 trees/ha using vase-grown trees. Moreover, the establishment of new plantations does not require large investments, and all cultivars can be used. Hence, native cultivars can be considered, which enables the pursuit of commercial strategies based on the enhancement of typicality and differentiation of production [1].

Super-intensive olive groves are characterized by planting densities of 1200–2500 trees/ha; the trees are spaced closely along rows (1–2 m) and trained to form a continuous vegetation wall. The model requires flat or slightly sloping land, very favorable environments (no risk of frost), good water availability (irrigation), and high technical expertise management [4]. The super-intensive model requires cultivars with limited vigor and compact vegetative habitus that are very fertile and productive. To date, the varieties that best fulfill most of these requirements are Arbequina and Arbosana (Spanish) and Koroneiki (Greek), which produce a standard, quality product suitable for large-scale retail trade. New varieties produced by genetic improvement have been added recently, such as Sikitita (obtained from Picual × Arbequina), Oliana (obtained from Arbequina × Arbosana), and Lecciana (obtained from Leccino × Arbosana) [3]. Attempts to reduce vigor have also been performed using agronomic approaches such as root constriction [5,6,7,8,9]. The major advantages of the super-intensive model are the rapid achievement of full production (3rd–5th year), the full mechanization of harvesting with straddle machines, with which it is possible to harvest a 1-hectare plot in 2 to 3 h, and the full/partial mechanization of pruning [10].

High-density olive orchards are characterized by planting densities intermediate between those of intensive and super-intensive crops. The wider planting distances should enable more cultivars to adapt to a system that creates vegetation walls, making it easier to grow without irrigation.

In intensive olive orchards, mechanized harvesting is performed using trunk shakers with an inverted umbrella interceptor frame. In super-intensive ones, mechanized harvesting is performed using straddle machines specifically designed for olive trees (wide tunnel); while in high-density olive orchards, continuous harvesting machines can be used on one side of the row at a time or on both sides at the same time up to a height of 4–5 m. Partial mechanized pruning can also be performed.

Based on the above, for high-density and super-high-density orchards, it is very important to choose low-vigor cultivars. However, based on current knowledge, only a few cultivars are available, which may limit the possibilities of oil production enhancement by using different cultivars [9]. Hence, it is crucial to increase our knowledge of the suitability of Italian olive germplasm to identify cultivars that can combine high productivity and suitability for intensive mechanization—through high- and very high-density planting systems—favoring the distinctive quality and character that diverse cultivars can offer. In fact, the widespread use of only a few cultivars could lead to the standardization of olive oil and a reduction in olive biodiversity [2]. On the other hand, enhancing oil production using native cultivars is especially important in Italy, where highly diverse soil and climate conditions have fostered the development of numerous cultivars. These contribute significantly to the differentiation and typicity of production.

The aim of the present work was to evaluate the agronomic behavior of several Italian cultivars, which, based on available information, can adapt to high-density planting conditions, enabling increased productivity of olive groves, conservation, and enhancement of local olive germplasm.

2. Materials and Methods

The experiment was carried out in 2020–2024, in central Italy, in the locality of Pozzo, Gualdo Cattaneo (PG), in a high-density olive orchard established in 2015. The trees, which were planted at a spacing of 5 m × 2 m (1000 trees/ha), included numerous Italian cultivars: Borgiona, Don Carlo, FS17, Gentile di Anghiari, Gentile di Montone, Giulia, Leccio del Corno, Maurino, Moraiolo, Pendolino, Piantone di Falerone, and Piantone di Mogliano. In addition, one international cultivar, Arbequina, was included due to its recognized suitability for high- and super-high-density planting systems. It was therefore used as a reference to assess the adaptability of the other cultivars to high-density cultivation.

The olive orchard is situated on hilly terrain with clay–loam soil. Annual precipitation varies between 700 and 1000 mm, depending on the year. Ground management was based on natural cover cropping. The trees were trained to form a continuous vegetative wall. Pruning was performed annually and was executed to maintain canopies within the dimensions (up to 1.5 m width and 2.5 m tall) that allow a straddle machine to execute harvesting [10]. This was achieved by applying selective pruning, removing branches that were too rigid (diameter > 3 cm) and protruded from the size limits of the harvesting machine (both laterally and in the apical portion of the canopy), as well as those that were damaged (e.g., broken during harvesting) or that were excessively shaded. Fertilization was carried out using chemical fertilizers containing nitrogen, phosphorus, and potassium. During the spring vegetative regrowth phase, each olive tree was supplied with 0.500 kg of a compound fertilizer, characterized by the following composition of macro- and microelements: nitrate N 3%, ammonium N 9%, P₂O₅ 12%, K₂O 17%, SO₃ 16.5%, Fe 0.1%, and Zn 0.01%. Furthermore, copper-based phytosanitary treatments were applied in the orchard both after pruning and following harvest, in accordance with best agronomic practices to ensure optimal plant health and protection. The orchard was drip-irrigated with a single line per tree row and 4 L h⁻¹ emitters placed at 1.5 m intervals along the line; water was supplied to meet 75% of the maximum evapo-transpiration demand. The total amount of irrigation water was about 400–500 m³ ha⁻¹ per year, according to the season. Drip irrigation was generally applied from July to the first half of September. Since the trees were quite uniform, for each cultivar, 3 replicates of 5 trees each were used, distributed across different rows in a randomized manner, for a total of 15 trees per cultivar, as in other agronomic studies [11,12,13,14,15].

The following measurements were taken and used to assess vegetative growth:

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Trunk diameter, measured at 30 cm above ground level.

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Tree height and canopy dimensions, i.e., height and width, which were used to calculate volume.

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The weight of the pruning material that was removed.

Harvesting took place in the first half of October during each year (2020–2024), and the yield per tree was recorded. Based on trunk and canopy growth data, as well as yield, productive efficiency was calculated as the amount of oil produced per unit of trunk cross-sectional area and per unit of canopy volume.

At harvest, three representative fruit samples were collected for each cultivar to determine their characteristics [16]. For each sample, the following parameters were recorded [17,18]:

• Individual fresh weight per fruit, determined using 100 olives per sample.
• Fruit water and oil content, measured using the InfraAlyzer 2000 Olive (ZEUTEC Opto-Elektronik GmbH Friedrich-Voß-Str.11, D-24768 Rendsburg, Germany), a chemical parameter analyzer that, by near-infrared spectroscopy (NIR) technology, allows the amount of water and fat in olive paste to be assessed directly on the sample, by SpectraAlyzer Software 4.0. Near-infrared optical readings were performed using 10 interference filters in the wavelength range between 1445 and 2310 nm.
• Degree of olive pigmentation (pigmentation index = p.i.), assessed using the same samples used for weight determination, by calculating a pigmentation index according to the following formula:

$$p.i.={\displaystyle \frac{\sum (i-ni)}{\mathrm{N}}}$$

where i varies as followed:

0 = completely green olives;

1 = yellow olives;

2 = olives with pigmentation on less than 50% of the epicarp;

3 = olives with pigmentation on more than 50% of the epicarp;

4 = olives with pigmentation on 100% of the epicarp;

5 = olives with pigmentation on 100% of the epicarp and less than 50% of the mesocarp thickness;

6 = olives with pigmentation on 100% of the epicarp and more than 50% of the mesocarp thickness;

7 = olives with pigmentation on 100% of the epicarp and 100% of the mesocarp thickness;

ni represents the number of olives in each pigmentation class, and N is the total number of olives in the sample [18].

The data were statistically analyzed by ANOVA according to a completely randomized design, and the averages were compared by Tukey’s test at a 0.05 significance level, using InfoStat Software (Grupo InfoStat, FCA, Universidad Nacional de Córdoba, Cordoba, Argentina). In the figures, the means are presented together with the standard errors.

3. Results

3.1. Vegetative Growth

The cultivars exhibited varying levels of vegetative growth. In particular, Don Carlo and Giulia had the statistically highest stem growth, at 94.1 cm² and 89.1 cm², respectively, measured as cross-sectional area, followed by Leccio del Corno, Maurino, Pendolino, and Piantone di Falerone. In contrast, Gentile di Montone had the lowest significant stem growth of only 55 cm². Intermediate values, not different from those of Arbequina, were measured in Borgiona, FS-17, Gentile di Anghiari, Moraiolo, and Piantone di Mogliano (Figure 1).

In terms of tree/canopy size, the differences among the cultivars were less pronounced (Figure 2, Figures S1 and S2). Gentile di Anghiari had the statistically largest canopy volume, equal to 10.6 m³, followed by Giulia, Don Carlo, Arbequina, Maurino, and Pendolino, ranging from 9.2 m³ to 8.2 m³, while Gentile di Montone, followed by Piantone di Mogliano, had the significantly smallest canopy volume, equal only to 5.4 m³. The remaining cultivars had intermediate values, generally similar to the value of Arbequina (Figure 2).

Pendolino showed the highest values of cumulative pruning biomass, significantly higher than those of Borgiona, Leccio del Corno, Piantone di Mogliano, and Gentile di Montone (Figure 3). Intermediate values, not different from those of Arbequina, were measured in all the other cultivars.

3.2. Yield and Yield Efficiency

Maurino, Leccio del Corno, and Piantone di Mogliano had significantly higher cumulative olive production, ranging from 35.6 to 32.2 kg of olives per tree, compared to the reference cultivar Arbequina, with 26.1 kg (Figure 4). Gentile di Anghiari, Moraiolo, and Pendolino, followed by Gentile di Montone and Giulia, had the significantly lowest cumulative production, ranging from 20.3 to 11.8 kg of olives per tree.

Leccio del Corno and FS-17 had the significantly highest oil yields, followed by Maurino, FS-17, Piantone di Mogliano, and Arbequina (Figure 5). The oil yields of Piantone di Falerone, Gentile di Anghiari, and Don Carlo were statistically not different from those of Arbequina. Considerably lower oil yields were observed in Borgiona, Gentile di Montone, Giulia, and Pendolino.

Overall, the cultivars with yields that were not statistically different than Arbequina also exhibited similar or higher production efficiency, particularly when efficiency referred to canopy volume (Figure 6). When efficiency referred to trunk cross-sectional area, FS-17, Leccio del Corno, Gentile di Anghiari, Maurino Gentile di Montone, and Piantone di Mogliano had values that were not significantly different from those of the reference cultivar, Arbequina. The remaining cultivars had lower efficiency values (Figure 7).

3.3. Fruit Characteristics at Harvest

Fruit characteristics were evaluated at harvest, which was conducted in mid-October in all years. The harvesting time was chosen according to the ripening stage of ‘Arbequina’, which is the reference cultivar.

The detachment force values of Moraiolo and Piantone di Mogliano were statistically the highest, at 5.29 N and 5.01 N, respectively, followed by Piantone di Falerone, Giulia, and FS-17, while all the other cultivars had values that were not statistically different from Arbequina (

Table 1. Fruit characteristics at harvest. Average values of the years 2020–2024. In each column, means accompanied by different letters are significantly different at p ≤ 0.05.

Cultivar	Detachment Force (N)		Fresh Weight (g)		Detachment Force/Weight Ratio (N/g)		Pigmentation Index (0–7)		Oil Content (%F.W.)		Oil Content (%D.W.)
Arbequina	4.04	cd	1.23	d	3.28	a	1.04	d	14.97	ab	40.31	abc
Borgiona	4.35	bc	2.88	a	1.51	d	0.99	d	9.35	c	26.45	d
Don Carlo	4.00	d	2.58	abc	1.55	d	0.43	d	12.00	bd	33.99	c
FS-17	4.68	abc	2.62	abc	1.79	d	1.47	cd	16.69	a	46.78	a
G. Anghiari	4.22	cd	2.78	ab	1.52	d	0.84	d	16.39	a	43.74	ab
G. Montone	4.17	cd	2.10	abcd	1.99	cd	3.52	a	13.79	ab	36.31	bc
Giulia	4.78	abc	2.99	a	1.60	d	1.18	d	14.25	ab	40.90	abc
Leccio del Corno	3.49	d	1.60	d	2.18	cd	0.69	d	13.91	ab	36.62	Bc
Maurino	3.58	a	1.91	bcd	1.87	d	2.46	b	11.63	cb	35.58	c
Moraiolo	5.29	a	1.82	cd	2.91	ab	2.19	bc	13.57	ab	34.20	c
Pendolino	3.47	d	1.38	d	2.51	bc	1.42	cd	10.31	c	26.60	d
P. Falerone	4.79	abc	3.01	a	1.59	d	2.69	b	14.38	ab	41.66	abc
P. Mogliano	5.01	ab	2.57	abc	1.95	cd	1.06	d	13.92	ab	38.70	bc

).

On average, the cultivars Arbequina, Pendolino, Leccio del Corno, Maurino, and Moraiolo had the statistically lowest fruit weights, ranging from 1 to 2 g (Table 1). All other cultivars had higher fruit weights (between 2 and 3 g).

Arbequina and Moraiolo, followed by Pendolino, had the highest fruit detachment force-to-weight ratio, an index used to assess susceptibility to mechanical harvesting (Table 1). All the other cultivars had relatively low values, indicating the possibility of obtaining harvest yields above 85% for all cultivars, in agreement with Farinelli et al. [19,20].

Regarding fruit pigmentation, most cultivars—Arbequina, Borgiona, Don Carlo, FS-17, Gentile di Anghiari, Giulia, Leccio del Corno, Pendolino, and Piantone di Mogliano—had very low average values, ranging from just above 0 to 2 (Table 1). The highest pigmentation value, approximately 3.5, was recorded for Gentile di Montone. Maurino, Moraiolo, and Piantone di Falerone had intermediate values. Gentile di Montone’s pigmentation index was significantly higher than that of the other cultivars.

The average oil content of the fruits—expressed on both a fresh and dry weight basis—was generally highest in the cultivars FS-17 and Gentile di Anghiari, at 16.69% and 16.39%, respectively, followed by Arbequina, Piantone di Falerone, Giulia, and Piantone di Mogliano (Table 1), whereas Borgiona and Pendolino had the significantly lowest values, at 9.35% 10.31%, respectively. The other cultivars had intermediate fruit oil contents.

4. Discussion

The cultivars examined exhibited differences in vegetative growth, particularly regarding stem diameter. These differences were less pronounced when expressed in terms of tree height and canopy volume, likely because tree height and canopy size are affected by pruning, which significantly contributes to maintaining vegetation in the available space.

The results obtained for Borgiona, Gentile di Montone, and Piantone di Mogliano confirm the limited vegetative vigor previously reported [21]. Regarding Maurino, while Farinelli and Tombesi [19] reported stem growth not different from that of Arbequina, while another study [9] observed greater growth, consistent with the present results. For FS-17, Camposeo et al. [21] reported greater stem growth than Arbequina, whereas subsequent studies found both a larger canopy with similar stem growth [22,23,24], like in the present work, and reduced growth [8]. Regarding Moraiolo, Farinelli and Tombesi [19] reported greater stem growth compared to Arbequina. These discrepancies across studies may be attributed to differences in tree age at the time of measurement, as well as to variations in environmental conditions and cultivation practices, including more or less severe topping and hedging. Among these factors, tree age appears particularly influential: in very young trees, growth differences among cultivars may not yet be pronounced [22,23,24].

Regarding pruning material, comparison with previously studied cultivars indicates that the cumulative amounts of pruning material recorded for Don Carlo, FS-17, and Maurino in the present study were greater than those of the reference cultivar Arbequina, whereas in a previous study, the values were similar [25]. However, the results for Maurino and Moraiolo were consistent with those reported in another study conducted under the same environmental conditions in central Italy, where the present investigation also took place [19]. When considering both the canopy size/volume and cumulative pruning material obtained in this study, it is notable that canopy size/volume exhibited considerably less variation among the cultivars than cumulative pruning material. This supports the fact that pruning played a significant role in standardizing canopy size/volume across the different cultivars and, as a result, in maintaining canopies within the available space [10].

Significant differences in production were found among the cultivars. In addition to the quantity of olives produced per tree, olive oil content is a critical factor in oil production, and this parameter varied among the cultivars. Five cultivars, namely, Leccio del Corno, Maurino, FS-17, Piantone di Falerone, and Piantone di Mogliano, had olive and oil yields that were not significantly different from those of Arbequina. In a previous study, Maurino had similar olive production but a lower oil yield compared to Arbequina [19]. FS-17 showed variable performance [22,25,26,27,28]. In a trial conducted in southern Italy, it outperformed Arbequina in terms of yield [22], while in a Spanish study, it produced less [26]. For FS-17 and Maurino, a relatively high yield efficiency was also reported in previous studies [19,22].

Regarding Arbequina, the reference cultivar, the yields recorded in central Italy in previous studies are in agreement with those observed in the present trial [19,27]. However, studies conducted in southern Italy and Spain reported significantly higher yields [26,28], likely attributable to more favorable climatic conditions. Indeed, a comparative study assessing the performance of Arbequina throughout various Italian growing regions clearly demonstrated a greater production potential in southern Italy compared to central Italy [29].

The yields recorded in the present study for the best-performing cultivars can be considered very promising in the sense that they are not different from those of the reference cultivar for high-density or super-intensive plantations, indicating the possibility of using local cultivars instead of a cultivar that is not part of one’s own olive germplasm. In fact, over the five-year period (2020–2024), the average olive yield per hectare per year was 5.2 t for Arbequina, 5.7 t for FS-17, 7.0 t for Leccio del Corno, 7.0 t for Maurino, 4.7 t for Piantone di Falerone, and 6.4 t for Piantone di Mogliano. The corresponding average annual oil yields per hectare were 0.73 t for Arbequina, 0.91 t for FS-17, 0.99 t for Leccio del Corno, 0.86 t for Maurino, 0.66 t for Piantone di Falerone, and 0.75 t for Piantone di Mogliano.

It is also important to note that in the present trial, the trees were planted at a spacing of 5 × 2 m (equivalent to 1000 trees per hectare). However, based on the vegetative development observed thus far, a denser planting configuration of 4 × 2 m (1250 trees per hectare) appears feasible, potentially, with low-vigor cultivars, increasing production by up to 25% thanks to the increase in the number of plants.

Furthermore, the timing of the harvest likely influenced oil yields. In this study, harvesting was conducted very early, during the first half of October, using the harvest period of the Arbequina cultivar as a reference. Delaying the harvest could lead to significant increases in oil yield. According to data in the literature, postponing harvest to the first half of November may result in oil yield increases of 30% or more. On the other hand, considering other studies, harvester efficiency could change due to increasing canopy volume as well as a higher DF/FW ratio [20]. To conclude the analysis of the vegetative and productive performance of the cultivars examined in this study, it is important to emphasize that the assessment of olive cultivar suitability for high-density and super-high-density orchards relies on several key factors. These include tree vigor (estimated by stem diameter growth and weight of pruning material); tree and canopy size, which affects the vegetative–productive balance of trees and determines the feasibility of using straddle harvesters; and both yield and yield efficiency [9,30]. Among the five top-performing cultivars, Piantone di Mogliano exhibited all tree vigor parameters, yield, and yield efficiency that were not different from those of the widely used reference cultivar Arbequina. These characteristics indicate that these cultivars possess all the traits necessary for successful cultivation in high- and super-high-density systems. FS-17, Leccio del Corno, Maurino, and Piantone di Falerone showed yield and yield efficiency that were not significantly different from those of Arbequina; however, they were characterized by greater stem diameter growth and/or higher cumulated pruning material, which may be considered disadvantages in such systems. All five cultivars maintained canopy sizes compatible with the use of straddle harvesters. This was achieved through the application of appropriate pruning practices; so far, these practices have not resulted in significant vegetative–productive imbalances, which are more commonly observed in more vigorous cultivars. Overall, the results demonstrate that, for the best-performing cultivars, it was possible, up to the ninth year after planting (2024), to maintain tree and canopy dimensions within the spatial constraints required for mechanical harvesting. This was accomplished through suitable pruning practices, without inducing significant vegetative–productive imbalances.

Research on tree architecture has demonstrated that cultivars most suitable for super-high-density orchards are those with a high degree of branching, with small-diameter branches and shoots, such as Arbequina and Arbosana [31,32]. In this context, most of the best-performing cultivars, namely, Leccio del Corno, Piantone di Mogliano, Maurino, and Piantone di Falerone, were also previously reported to exhibit favorable architectural traits [23,32,33]. Lodolini et al. [23] found FS-17 to be less suitable from an architectural standpoint, underscoring the need for more targeted and precise pruning interventions, as also suggested in a previous study [25].

The various cultivars showed significant differences in fruit weight, color, and oil content. These differences are due to cultivar characteristics and essentially correspond to those reported in the literature for the cultivars used in this trial [34,35,36,37]. Of particular interest are the early and intense oil accumulation in FS-17 and Gentile di Anghiari and the low/slow oil accumulation in Borgiona. Moreover, it is well established that the ratio between detachment force and fruit weight is a key indicator of a cultivar’s suitability for mechanical harvesting. In particular, values around 2 or lower are associated with harvesting efficiencies exceeding 90% [20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38]. It is noteworthy that most of the cultivars, including the best-performing ones (FS-17, Leccio del Corno, Maurino, Piantone di Falerone, and Piantone di Mogliano), had values lower than that of Arbequina and close to or lower than 2, indicating a good potential for mechanical harvestability even at an early stage, given that the reported fruit characteristics correspond to the month of October.

5. Conclusions

In conclusion, this study has pointed out that there are several local cultivars that can be used instead of the reference cultivar for high-density or super-intensive plantations, improving orchard productivity and increasing biodiversity, even in traditional olive cultivation areas. Moreover, low vigor and high production efficiency were confirmed for the cultivar ‘Arbequina’, as previously reported in several studies, thereby reaffirming its suitability for high-density and super-high-density cultivation systems.

Regarding Leccio del Corno, Piantone di Falerone, and Piantone di Mogliano, there is a lack of medium- to long-term data on their performance under such conditions. Therefore, the results presented here offer the first evidence of their yield potential in high-density olive orchards. In general, the favorable productive performance of these cultivars is further supported by their relatively high yield efficiency, both when expressed as per unit of canopy volume and per unit of trunk cross-sectional area.

In addition, Leccio del Corno, Maurino, FS-17, Piantone di Falerone, and Piantone di Mogliano had yields and production efficiencies that were not different from those of ‘Arbequina’. Notably, during the first nine years after planting, these cultivars were shown to maintain compact canopies well suited to high-density systems through the application of selective pruning, without displaying significant vegetative–reproductive imbalances.

Overall, the results are encouraging and suggest that these cultivars may be suitable candidates for high- and super-high-density olive orchards, allowing the use of local germplasm. This suitability is further supported by their favorable fruit characteristics, which appear to facilitate efficient mechanical harvesting, as well as by their architectural traits.

However, additional long-term data are required for a more comprehensive assessment of these cultivars, particularly with respect to their ability to maintain canopy dimensions compatible with straddle harvester use, while also ensuring a stable vegetative–reproductive balance over time.