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Article

Occurrence and Abundance of Hemiptera Auchenorrhyncha Associated with Traditional and Super-High-Density Olive Groves in Tuscany (Central Italy), with a Particular Focus on Xylella fastidiosa Vectors

by
Gargani Elisabetta
1,*,
Francardi Valeria
2,
Cutino Ilaria
1,
Simoni Sauro
1,
Nencioni Anita
1,
Bigiotti Gaia
1 and
Landi Silvia
1
1
Council for Agricultural Research and Economics, Research, Centre for Plant Protection and Certification, Via Di Lanciola 12/A, 50125 Florence, Italy
2
Independent Researcher, Via Paoletti, 8, 50134 Florence, Italy
*
Author to whom correspondence should be addressed.
Crops 2025, 5(5), 73; https://doi.org/10.3390/crops5050073
Submission received: 8 September 2025 / Revised: 13 October 2025 / Accepted: 16 October 2025 / Published: 18 October 2025
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Abstract

In recent years, the spread of the phytopathogenic bacterium Xylella fastidiosa Wells et al., 1987 (Bacteria: Proteobacteria, Gammaproteobacteria) has posed a significant threat to olive cultivation in Italy, particularly in regions of high economic and agronomic value such as Apulia (Southern Italy). In this two-year study (2019–2020), we investigated the Auchenorrhyncha community in three representative olive farms in Tuscany (Central Italy), another region with highly valuable olive-growing, comparing traditional (400 trees/ha) and super-high-density (1500 trees/ha) management systems. Adult insects were collected monthly from May to November using sweep net sampling on both olive tree canopies and herbaceous ground cover. In total, 1844 individuals belonging to 25 genera and five families were identified. Philaenus spumarius L. and Neophilaenus campestris (Fallén) (Cercopoidea: Aphrophoridae) were confirmed as the most prevalent X. fastidiosa vectors in each site. However, data analysis revealed that Auchenorrhyncha community composition was significantly influenced by site and vegetation stratum, but not by olive grove management systems. These findings contribute to a deeper understanding of the composition of Auchenorrhyncha communities associated with olive groves, highlighting that new super-high-density management does not influence the presence and abundance of X. fastidiosa vectors.

1. Introduction

In recent decades, Italian olive oil production has experienced a marked decline. From 674,000 tons in 1991–1992, production dropped to 315,000 tons in 2021–2022 and fell below 250,000 tons in 2022 [1]. The challenges facing Italian olive cultivation arise from multiple factors, including structural issues such as land fragmentation, limited generational turnover, obsolete orchards, and often low mechanization, and reduced productivity. These problems are further exacerbated by increasingly strong competition from countries such as Spain, Tunisia, Greece, and Morocco, which are modernizing their olive-growing systems with intensive and super-intensive orchards and advanced technologies [2,3,4]. Despite the current crisis, global demand for Italian olive oil remains high. Its success is founded on three key strengths: a rich genetic heritage and biodiversity, consistent production of premium-quality extra virgin olive oil, and a strong, territorial identity that imparts unique identity to each product. In response, the Italian government has launched the National Olive Oil Strategic Plan, focusing on promoting new plantings, improving economic efficiency, and enhancing sustainability. Within this strategic framework, high-density and super-high-density olive orchards play a crucial role in revitalizing the sector. By reducing production costs and increasing yields per hectare, these systems could support economic recovery. The super-high-density plantings are typically established on flat or gently sloping terrain and designed to develop a hedge-like canopy structure, accommodating 1500–2000 trees per hectare and allowing complete mechanization of operations such as pruning and harvesting [5,6].
In Tuscany (Central Italy), olive trees cover approximately 87,000 hectares [7], 90% of which are located in hilly or low-mountain areas. Olive cultivation in the region can be categorized into four management types: marginal (<250 plants/ha), traditional (≈400 plants/ha), intensive, and super-high-density olive groves, the latter with a planting density between 600 and 1500 trees/ha [8]. Although Tuscany is not among Italy’s most productive regions, it remains highly significant for PDO (Protected Designation of Origin) and PGI (Protected Geographical Indication) olive oils. Tuscany is also an important exporter with a well-established international market [7].
With the recent expansion of super-high-density (SHD) olive groves in Central Italy, research has increasingly focused on the effects of this management system on key olive pests [6,9]. In fact, pest and disease management represents a major bottleneck in olive production.
Among the most serious threats is the “olive quick decline syndrome” (OQDS), which emerged in the olive groves of Apulia (Southern Italy). This devastating disease is caused by the bacterium Xylella fastidiosa Wells et al., 1987 (Bacteria: Proteobacteria, Gammaproteobacteria) [10,11,12] and transmitted by xylem-sap-feeding insects belonging to the suborder Auchenorrhyncha [13]. In Italy, confirmed vectors include the spittlebugs Philaenus spumarius L., P. italosignus (Drosopoulos & Remane), and Neophilaenus campestris (Fallén), while other species from the Cicadellidae, Cercopidae, and Aphrophoridae families are considered potential vectors [14,15].
Currently, insect vectors of X. fastidiosa represent the primary target of OQDS control strategies [11,16]. As a result, increasing research efforts have been directed toward studying the Auchenorrhyncha fauna associated with olive groves, and significant progress has been made in understanding the ecology and distribution of X. fastidiosa vectors across Europe.
The presence of spittlebug vectors in European olive groves has been repeatedly documented [17,18,19,20]. In particular, P. spumarius often occurs at high or very high densities, both on herbaceous ground cover and olive trees, confirming its key role as the main X. fastidiosa vector in olive agroecosystems [21]. However, the ecological factors influencing its occurrence and abundance are only partially understood [22,23,24], underlining the need for further studies to predict the dynamics and potential spread of P. spumarius and other X. fastidiosa vectors in different regions.
The dispersal capability of these vectors is also a major concern. Philaenus spumarius exhibits strong long-distance flight ability, facilitating bacterium spread over wide areas [25,26]. Moreover, environmental factors such as temperature and vegetation type significantly influence vector abundance and distribution, thereby affecting disease transmission dynamics [24].
The recent detection of P. spumarius and N. campestris infected by X. fastidiosa in Southern Tuscany (Monte Argentario promontory) [27] has prompted studies focusing on the Auchenorrhyncha communities associated with economically important olive groves and natural areas in Central Italy.
Although SHD olive orchards are rapidly expanding across the Mediterranean Basin and their agronomic benefits—such as reduced yield alternation, higher productivity, full mechanization, and lower production costs—are well documented, only limited research has investigated their impact on key olive pests, including the olive fruit fly Bactrocera oleae (Rossi) (Diptera, Tephritidae) [9]. Studies assessing the presence and dynamics of X. fastidiosa vectors in high- and super-high-density olive groves are still lacking.
In this context, the present two-year investigation aimed to achieve the following:
  • Identify and characterize the Auchenorrhyncha insect community occurring in three olive farms located in Tuscany, a key region for Italian olive cultivation.
  • Assess how different farming systems (traditional vs. super-high-density) and vegetation strata (herbaceous ground cover vs. olive tree canopy) influence the occurrence and abundance of these insects, with particular attention to the confirmed X. fastidiosa vectors, P. spumarius and N. campestris.
The results of this study will provide valuable insights into the ecology of X. fastidiosa vectors, contributing to a better understanding of factors influencing their occurrence in olive groves. Furthermore, improved knowledge of how farming systems affect the presence of P. spumarius and N. campestris may enhance the effectiveness of integrated control strategies, helping to prevent or limit the spread of X. fastidiosa.

2. Materials and Methods

2.1. Study Sites and Experimental Design

The experimental areas were located in three different olive farms; these were representative of Tuscany olive tree production, characterized by two types of management each, traditional (TRA: 400 plants/hectare) and super-high-density (SHD: 1500 plants/hectare): Olive Farm PR, “Poggio a Remole” (province of Florence), Olive Farm GT “Giganti” (province of Siena), and Olive Farm BM “Barban” (province of Siena). In each farm, two adjacent areas were selected to compare the samplings between the SHD and TRA olive orchard systems [9]. The selected farms were characterized by similar agricultural management, soil texture and climatic conditions; the only differences were olive tree varieties, planting density, and consequently the shape of the tree canopy (Table 1). The only phytosanitary measures implemented in each farm were those for the olive fruit fly Bactrocera oleae control, and each farm used the same approach (IPM strategy). The most common weeds found on the herbaceous cover of the different olive groves were Avena sp., Bromus hordeaceus L., Hordeum murinum L., Lolium perenne L., Phalaris paradoxa L., Hedysarum coronarium L., Medicago polymorpha L., Trifolim alexandrinum L., Trifolium angustifolium L., Trifolium campestre Schreb., Cichorium intibus L., Convolvolus arvensis L., Geranium sp., Helminthotheca echioides (L.), Senecio vulgaris L., Sonchus asper (L.), and Taraxacum officinalis (Weber). Weed species identification was based on dichotomous keys [28].
The three experimental sites were in hilly areas, with high clay content in the soil. According to the Köppen climate classification, the Florence (PR) site was identified as temperate, with hot summers and no dry season, whereas the two sites in the Siena province were classified as temperate with hot and dry summers. Across all locations, from 2019 to 2020, the highest temperatures were recorded in the June–September period, with no differences between years (maximum values of 32–33 °C in August). The lowest annual rainfall was observed in June 2019 on all three farms. In the Siena province sites, the lowest yearly precipitation was registered in 2020 (751.6 mm in Giganti (GT) and 670.8 mm in Barban (BM); the lowest monthly values were measured in June 2019 (3.4 mm in GT and 0.6 mm in BM) [9].

2.2. Insect Collection

Samplings were conducted during 2019 and 2020 in all surveyed olive groves, where Auchenorrhyncha adult specimens were collected monthly from May to November using an entomological sweep net.
Specifically, to conduct the survey, each olive grove (both traditional and super-high-density) covered 1.5 ha and was virtually divided into four quadrants. In traditional olive orchards (TRA), in each quadrant, five olive trees were randomly selected at every sampling date, and their canopies (TC, tree canopy) were sampled by beating them with an entomological sweep net. Each plant was beaten once from each cardinal direction. In total, 20 sweeps were carried out per quadrant. In the super-high-density (SHD) olive groves, where the tree canopies were contiguous and could not be beaten individually, sweepings were carried out on five adjacent trees within the same row, for a total of 20 sweeps. Furthermore, 20 sweeps were also randomly performed on spontaneous weeds (HC, herbaceous cover) in each field, both under and between the plants in the rows or at the olive grove edge.
The captured insects were collected from the sweep nets with an entomological aspirator and immediately placed individually in a 1.5 mL tube containing 95% alcohol.

2.3. Insect Identification

The insects collected were transferred to CREA DC facilities and kept in the laboratory until identification. Spittlebug specimens, along with leafhoppers, were identified at the genus or species level using taxonomical keys [29,30,31,32,33].
Taxonomic characterization was performed by observing each specimen under a stereomicroscope, with a specific focus on external morphology, and, when possible, male individuals were dissected and clarified (by boiling gently in water-diluted 10% KOH for 1–2 min) to prepare male genitalia in a non-permanent slide (Hoyer liquid) for optical microscopy.

2.4. Data Analysis

The sampled Auchenorrhyncha, arranged by genus, were classified using the dominance criteria. Dominance was calculated as the percentage of individuals of a given genus compared with the total number of individuals of all genera found. A genus is classified as “dominant” if it constitutes > 10% of the total number of individuals, “influent” if it is in the range 5–10%, and “recedent” if the total number of individuals is <5% of the total [34]. To gain a deeper understanding of a genus’s ecological significance, we went beyond simple population counts. We used a relative importance (RI) score that combines a species’ abundance with its frequency of occurrence. This metric allows us to fairly assess genera that are consistently present but in low numbers, a crucial distinction from those that are plentiful but appear only sporadically.
We calculated the RI using the following formula:
RI = (ni/nt) × (mi/mt) × 100.
Here, ni is the number of individuals of a given genus, nt is the total number of individuals, mi is the number of samples containing the genus, and mt is the total number of samples. This formula represents the proportion of individuals for a genus multiplied by the proportion of samples it was found in, expressed as a percentage. Finally, we categorized genus based on their RI score: “very frequent” for a score of 1% or higher, “frequent” for scores between 0.02% and 0.99%, and “rare or occasional” for scores of 0.019% or lower [35].
PERMANOVA (Permutational Multivariate Analysis of Variance), a non-parametric method, was adopted to test for significant differences, over all insect communities and considering potential and ascertained X. fastidiosa vectors, by referring to site, management (TRA vs. SHD) and vegetation stratum. The frequency of presence of the ascertained or potential X. fastidiosa vectors was analyzed by the chi-square test to evaluate the possible significant presence of some genera. With PERMANOVA, the Bray–Curtis dissimilarity index, robust in guaranteeing inference when data includes abundance data for multiple genera across different samples or sites, was adopted to compare community composition and when dealing with “zero-inflated” data. Each PERMANOVA test was combined with a multivariate dispersion test. All the calculations were made by Past 4.11 [36].

3. Results

3.1. Identification and Abundance of Insects

Over the two-year study period, a total of 1844 individuals belonging to 25 genera of Hemiptera Auchenorrhyncha were collected across all surveyed olive groves. The family Cicadellidae exhibited the highest biodiversity, encompassing 16 identified genera, followed by Aphrophoridae (4 genera), Issidae (2), Cixidae (2) and Dictyopharidae (1 genus) [Table S1]. Among genera, Agalmatium was the most abundant, with 777 specimens recorded. Regarding the known vectors of X. fastidiosa, P. spumarius was the most frequently collected species (195 individuals), followed by N. campestris (140 specimens).
Overall, Agalmatium (42.13%) and Philaenus (10.57%) were by far the most abundant genera, both categorized as very frequent. Several other taxa—including Cicadella (5.15%) and Neophilaenus (7.79%)—both confirmed as X. fastidiosa vectors, and non-vector leafhoppers such as Anoplotettix, Synophropsis, Athysanus, Macropsis, Issus, and Euscelis were consistently recorded and classified as frequent, together accounting for 36.2% of the total Auchenorrhyncha collected.
Concerning the abundance and relative importance (RI) of the different genera collected, results are summarized in the table below (Table 2).
Conversely, several taxa were represented by a few individuals, such as Allygus, Aphrodes, Aphrophora, Evacanthus, Hyalestes, Ledra, Oncopsis, Pediopsis, and Reptalus, each represented by fewer than five specimens and thus considered rare.
The analysis of abundance and relative importance (RI) among taxa indicated a strong dominance by a limited number of genera, while most occurred sporadically and in low densities. This pattern suggests that only a restricted subset of Auchenorrhyncha taxa play a central role within the studied agroecosystem, whereas the majority contribute only marginally to the overall community structure.

3.2. Site, Management (TRA vs. SHD) and Vegetation Stratum Effects on Auchenorrhyncha Community

PERMANOVA analysis revealed significant differences in the overall community composition among sites and vegetation strata. The presence and abundance of genera were strongly influenced by the sampling site (PERMANOVA: F = 3.285, p < 0.001; multivariate dispersion: F = 2.009, p = 0.131), with the PR site yielding the highest number of collected Auchenorrhyncha (640 individuals).
The vegetation stratum also exerted a significant effect on both presence and abundance (PERMANOVA: F = 6.524, p < 0.001; multivariate dispersion: F = 8.122, p < 0.001). The greatest number of specimens (1,042 individuals) was collected from the herbaceous stratum. It is worth noting that the significance observed in multivariate dispersion suggests that part of the detected variation might be attributed not only to the effect of the factor itself but also to differences in the variability of dispersion within groups. In contrast, management type (TRA vs. SHD) had no significant effect on community composition (PERMANOVA: F = 1.079, p = 0.3445; multivariate dispersion: F = 3.482, p = 0.037), indicating that management practices played a negligible role relative to environmental and structural factors.

3.3. Focus on Potential and Ascertained Vectors

Within the surveyed olive groves, in addition to confirmed vectors, potential vectors were also identified. Among Aphrophoridae, Lepyronia coleoptrata (L.) (28 individuals in total) and Aphrophora sp. (4 individuals) were found.
Regarding the confirmed vectors, P. spumarius and N. campestris were the most abundant taxa across all farms, with notably high numbers recorded at Poggio a Remole (PR) (29.8%). The same species were also present at the other two sites, GT (18.9%) and BM (10.7%), though in lower numbers. Cicadella viridis reached relatively high abundance (5.15%), particularly at PR under TRA management, while L. coleoptrata and Aphrophora sp. were recorded in much smaller numbers across all sites and regardless of management system (Figure 1). The frequency and abundance of these potential and confirmed vector species differed significantly (chi-square = 409.8; df = 5; p < 0.0001).
As for the competent vectors P. spumarius and N. campestris, their seasonal trends for all three farms and for the two-year period are illustrated in the following figures (Figure 2 and Figure 3).
The meadow spittlebug, P. spumarius, showed two population peaks, one in spring and the other in autumn in both the olive groves, traditional (TRA) and super-high-density (SHD). During summer, a consistent reduction in the population was observed in all olive crops.
Concerning N. campestris, two population peaks were highlighted during the year. The first occurred in June and the second in October, without great difference between the two different managements.
Statistical analysis compared the two spittlebug species, N. campestris and P. spumarius, indicating a comparable occurrence across the two-year survey period. Neophilaenus campestris was detected in 24.5% of the 204 samplings, whereas P. spumarius was recorded in 32.35% of the same total (chi-square = 3.084; p = 0.079).
PERMANOVA results, consistent with those obtained for the entire Auchenorrhyncha community, revealed significant effects of both site and vegetation stratum on vector distribution. A significant site effect was observed (PERMANOVA: F = 5.505, p < 0.001; multivariate dispersion: F = 13.63, p < 0.001) with marked differences between Poggio a Remole (PR) and the other two locations (GT and BM). A significant effect of vegetation stratum was also detected (PERMANOVA: F = 4.845, p = 0.013; multivariate dispersion: F = 0.990, p = 0.329), with higher abundance of both vectors in herbaceous cover (Table S1).

4. Discussion and Conclusions

The two-year survey conducted in traditional (TRA) and super-high-density (SHD) olive groves across three farms in Tuscany enabled the characterization of the local Auchenorrhyncha community and the assessment of known and potential vectors of X. fastidiosa. Overall, 25 genera were identified, confirming a relatively rich Auchenorrhyncofauna associated with olive ecosystems in Central Italy. The predominance of Agalmatium and Philaenus is consistent with findings from other Mediterranean olive-growing regions [37,38,39], although, within the scope of this study, no epidemiological role can be attributed to Agalmatium.
Our results are in line with previous studies on arthropod communities in agricultural landscapes [35]. The observation that a small fraction of the total taxa accounted for a large proportion of total abundance reflects a well-documented trend in simplified agricultural ecosystems. This pattern contrasts with the more balanced species distributions typically observed in complex natural habitats, emphasizing the influence of agricultural management on local biodiversity structure.
The high abundance of a few dominant genera indicates low community evenness. While dominance by a limited number of species may suggest efficient resource exploitation, it also raises concerns regarding ecosystem resilience. Communities dominated by a few taxa may be more vulnerable to disturbances such as pest invasions or changes in pesticide regimes.
From an epidemiological perspective, the detection of the confirmed vectors P. spumarius and N. campestris at all sites is of particular concern. Although their abundance was moderate, the seasonal dynamics—characterized by spring and autumn peaks—indicate periods of heightened potential for pathogen transmission. This pattern aligns with observations from Greece [18,38,40] but contrasts with the summer peak reported in Apulia [39], highlighting how local climatic conditions and vegetation structure can shape vector ecology. Philaenus spumarius was the most abundant species with 195 adults collected, occurring in 32.35% of samples (66 out of 204), followed by N. campestris with 140 individuals, present in 24.51% of samples (50 out of 204). These results are consistent with previous Auchenorrhyncha surveys in European olive groves, which consistently report P. spumarius as the dominant species [34,38,40]. In Greece, N. campestris is reported as infrequent [40], a trend also observed in Apulia [41].
Another notable finding is the consistent presence of C. viridis, a species demonstrated to be a competent but inefficient vector of X. fastidiosa [26]. Its confinement to the herbaceous stratum underscores the importance of ground cover management in influencing vector populations. The detection of additional potential vectors (L. coleoptrata and Aphrophora sp.), although at low densities, indicates that biodiversity monitoring should not be restricted to the two main confirmed vectors.
Multivariate analyses revealed that site location and vegetation stratum were the primary determinants of community composition, whereas olive grove management (TRA vs. SHD) had no significant effect on vector abundance or diversity. This suggests that the transition to SHD cultivation, despite its substantial agronomic implications, does not inherently increase the risk of X. fastidiosa vector proliferation. Previous research has explored the effects of landscape and management practices on vector abundance [22,41], yet the specific influence of olive grove planting density has remained largely unexamined. Given the ongoing expansion of SHD systems in Italy, this study addresses a key knowledge gap. Our findings are consistent with those of Landi et al. [9], who reported that SHD cultivation does not exacerbate infestations by major olive pests, with the exception of Bactrocera oleae. Collectively, these observations support a more balanced risk assessment regarding the sustainability of SHD systems in Central Italy.
From a practical standpoint, the strong association between vector abundance and vegetation stratum highlights the crucial role of ground cover management in reducing the risk of pathogen introduction and spread, in agreement with previous findings [16]. Targeted interventions such as mowing, grazing, or selective herbicide application during peak vector activity could substantially decrease populations of P. spumarius and N. campestris. However, these measures must be carefully calibrated to minimize adverse effects on biodiversity, soil health, and broader agroecological functions.
At a broader scale, the results underscore the importance of region-specific epidemiological surveillance. Vector ecology is highly sensitive to local environmental conditions [22,24]; thus, generalizations from Apulia or other Mediterranean areas may not fully apply to Central Italy. Integrated monitoring programs that combine entomological surveys with molecular screening for X. fastidiosa in vectors are essential for early detection and the implementation of targeted containment measures
This study also identifies several research gaps requiring further investigation:
  • Vector competence under Tuscan conditions: While the presence of vectors is confirmed, their transmission efficiency in local agroecosystems remains unquantified.
  • Landscape-level drivers: The role of surrounding vegetation and landscape connectivity in supporting vector populations should be explored further, especially since plantation density appears unrelated to vector abundance.
  • Long-term monitoring under climate change: Shifts in temperature and precipitation patterns may alter spittlebug phenology and abundance, potentially influencing epidemiological risk over time.
In conclusion, this study demonstrates that the adoption of SHD olive groves does not increase the risk posed by X. fastidiosa vectors compared with traditional systems. Instead, vector populations appear to be influenced primarily by herbaceous cover management, spontaneous vegetation along the olive grove border, irrigation practices, microclimate, cultivar selection, and phytosanitary interventions.
Nevertheless, the consistent presence of competent vectors confirms that Tuscan olive groves remain vulnerable to X. fastidiosa. A multidisciplinary approach integrating vector ecology, agronomic management, and phytosanitary monitoring will be essential to safeguard the future of Tuscan olive production and, by extension, the broader Italian olive oil sector.

Supplementary Materials

The following supporting information can be downloaded at https://www.mdpi.com/article/10.3390/crops5050073/s1. Table S1: Auchenorrhyncha genera and species identified in the three olive grove farms (PR, GT, BM), during the two-year samplings (2019–2020) in Tuscany (Central Italy). HC: herbaceous cover; TC: tree canopy.

Author Contributions

Conceptualization and methodology, G.E., F.V., L.S. and C.I. G.E. performed insect identification. F.V. wrote the paper draft. L.S., S.S., N.A. and B.G. analyzed the data and performed statistical analysis. G.E. and S.S. revised the paper. All authors have read and agreed to the published version of the manuscript.

Funding

This work was supported by Italian National Project DI.OL, funded by MASAF under the grant number prot. no. 23774 (17 September 2017).

Data Availability Statement

The original data presented in this study are available on request from the corresponding author.

Acknowledgments

The authors thank the owner and the technicians of the farms Poggio a Remole, Giganti and Barban. Many thanks to Elisa Bianchetto for the taxonomic identification of herbaceous cover. A big thanks also to Claudia Benvenuti, Donatella Goggioli, Stefania Simoncini, Silvia Guidi and Franca Tarchi, technicians of CREA DC.

Conflicts of Interest

The authors declare no conflicts of interest.

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Figure 1. Number of vectors and potential vectors specimens, during the two-year samplings (2019–2020) on the three farms (Poggio a Remole (PR), Giganti (GT), Barban (BM)) in Tuscany (Central Italy), and in different olive groves with traditional (TRA) and super-high-density (SHD) management.
Figure 1. Number of vectors and potential vectors specimens, during the two-year samplings (2019–2020) on the three farms (Poggio a Remole (PR), Giganti (GT), Barban (BM)) in Tuscany (Central Italy), and in different olive groves with traditional (TRA) and super-high-density (SHD) management.
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Figure 2. Total number of Philaenus spumarius collected monthly in super-high-density (SHD) and traditional (TRA) olive groves, in 2019 and 2020, on the three farms surveyed in Tuscany (Central Italy).
Figure 2. Total number of Philaenus spumarius collected monthly in super-high-density (SHD) and traditional (TRA) olive groves, in 2019 and 2020, on the three farms surveyed in Tuscany (Central Italy).
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Figure 3. Total number of Neophilaenus campestris collected monthly in super-high-density and traditional olive groves, in 2019 and 2020, on the three farms surveyed in Tuscany (Central Italy).
Figure 3. Total number of Neophilaenus campestris collected monthly in super-high-density and traditional olive groves, in 2019 and 2020, on the three farms surveyed in Tuscany (Central Italy).
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Table 1. Sampling sites, geographical coordinates, climate parameters, soil characteristics, and olive orchard features in three olive-growing farms in Tuscany (Central Italy).
Table 1. Sampling sites, geographical coordinates, climate parameters, soil characteristics, and olive orchard features in three olive-growing farms in Tuscany (Central Italy).
SitesGeographical PositionClimate ParametersSoil texture USDAOlive Orchard Features
CoordinatesAltitude a.s.l. (m)Koppen Climate TypesMean Air Temperature (°C)Mean Annual Precipitation (mm) Olive Cultivar in Super- High Density (SHD) and Traditional (TRA) PlantationsSoil Management
Poggio a Remole (PR), Florence43.800183 N; 11.403579 E260Cfa14.7940ClaySHD: Leccio del Corno, Tosca, Diana TRA: Frantoio, Leccino, MoraioloConventional tillage, mineral, fertilization
Giganti (GT), Siena43.275739 N; 11.603974 E280Csa14.5880Silty clay, LoamSHD: Frantoio, Leccino, Moraiolo, Pendolino, Leccio del Corno, Correggiolo, Maurino, Vittoria selection TRA: Frantoio, Leccino, Moraiolo, PendolinoGreen Cover, organic fertilization
Barban (BM), Siena43.0940 N; 11.2316 E147Csa14.7890Clay LoamSHD: Arbequina TRA: Correggiolo, Pendolino, LeccinoConventional tillage, mineral, fertilization
Cfa: temperate, no dry season, with hot summers; Csa: temperate, with dry season and hot summers.
Table 2. Number of collected individuals and relative importance (RI). (***) very frequent with RI equal to or higher than 1%; (**) frequent, with RI between 0.02% and 0.99%; (*) occasional or rare, with RI equal to or lower than 0.019%.
Table 2. Number of collected individuals and relative importance (RI). (***) very frequent with RI equal to or higher than 1%; (**) frequent, with RI between 0.02% and 0.99%; (*) occasional or rare, with RI equal to or lower than 0.019%.
GenusNumberRI
Agallia38 **
Agalmatium777***
Allygus3 *
Anoplotettix90 **
Aphrodes1 *
Aphrophora4 *
Athysanus71 **
Cicadella95 **
Dictyophara28 **
Euscelis45 **
Evacanthus3 *
Hyalesthes9 *
Issus67 **
Ledra2 *
Lepyronia28 **
Macropsis70 **
Macrosteles18 **
Neophilaenus140 **
Oncopsis1 *
Pediopsis2 *
Philaenus195***
Platymetopius24 **
Reptalus2 *
Synophropsis87 **
Thamnotettix44 **
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Elisabetta, G.; Valeria, F.; Ilaria, C.; Sauro, S.; Anita, N.; Gaia, B.; Silvia, L. Occurrence and Abundance of Hemiptera Auchenorrhyncha Associated with Traditional and Super-High-Density Olive Groves in Tuscany (Central Italy), with a Particular Focus on Xylella fastidiosa Vectors. Crops 2025, 5, 73. https://doi.org/10.3390/crops5050073

AMA Style

Elisabetta G, Valeria F, Ilaria C, Sauro S, Anita N, Gaia B, Silvia L. Occurrence and Abundance of Hemiptera Auchenorrhyncha Associated with Traditional and Super-High-Density Olive Groves in Tuscany (Central Italy), with a Particular Focus on Xylella fastidiosa Vectors. Crops. 2025; 5(5):73. https://doi.org/10.3390/crops5050073

Chicago/Turabian Style

Elisabetta, Gargani, Francardi Valeria, Cutino Ilaria, Simoni Sauro, Nencioni Anita, Bigiotti Gaia, and Landi Silvia. 2025. "Occurrence and Abundance of Hemiptera Auchenorrhyncha Associated with Traditional and Super-High-Density Olive Groves in Tuscany (Central Italy), with a Particular Focus on Xylella fastidiosa Vectors" Crops 5, no. 5: 73. https://doi.org/10.3390/crops5050073

APA Style

Elisabetta, G., Valeria, F., Ilaria, C., Sauro, S., Anita, N., Gaia, B., & Silvia, L. (2025). Occurrence and Abundance of Hemiptera Auchenorrhyncha Associated with Traditional and Super-High-Density Olive Groves in Tuscany (Central Italy), with a Particular Focus on Xylella fastidiosa Vectors. Crops, 5(5), 73. https://doi.org/10.3390/crops5050073

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