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Article

Revealing the Influence of Rootstock Choice on Clementine Mandarin Leaves and Peel Volatile Profile

by
Vasileios Ziogas
1,
Evgenia Panou
2,
Konstantia Graikou
2,
Christos Ganos
2,
Evgenia Ntamposi
3 and
Ioanna Chinou
2,*
1
Institute of Olive Tree, Subtropical Plants and Viticulture, Hellenic Agricultural Organization-DIMITRA (ELGO-DIMITRA), 73134 Chania, Greece
2
Lab of Pharmacognosy and Chemistry of Natural Products, Department of Pharmacy, School of Health Sciences, National & Kapodistrian University of Athens, 15771 Athens, Greece
3
Ministry of Rural Development and Food, 11143 Athens, Greece
*
Author to whom correspondence should be addressed.
Horticulturae 2025, 11(5), 523; https://doi.org/10.3390/horticulturae11050523
Submission received: 14 April 2025 / Revised: 9 May 2025 / Accepted: 12 May 2025 / Published: 13 May 2025
(This article belongs to the Section Fruit Production Systems)
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Abstract

:
This study investigates the impact of rootstock selection on the essential oil (EO) composition of clementine mandarin (Citrus clementina Hort. ex Tan.) var. SRA 63 cultivated in southern Greece. EOs were extracted from the peel and leaves of trees grafted on four commonly used rootstocks: Cleopatra mandarin, sour orange, Troyer citrange, and Swingle citrumelo. The GC-MS analysis revealed significant qualitative and quantitative differences in EO profiles across the different rootstock combinations. In peel EOs, limonene was the dominant compound, particularly in trees grafted onto Cleopatra mandarin and Swingle citrumelo, while Troyer citrange favored a more diverse chemical profile rich in oxygenated monoterpenes, sesquiterpenes, and aldehydes. Leaf EOs were characterized by high levels of sabinene, linalool, and limonene, with Swingle citrumelo promoting sabinene production and Troyer citrange enhancing limonene content and sesquiterpene diversity. Sour orange showed an intermediate effect, increasing both compound diversity and abundance. These results underscore the critical role played by rootstock in modulating the biosynthesis of volatile compounds, likely through physiological and molecular interactions with the scion. These findings offer valuable insights into optimizing EO yield and quality in citriculture and support the broader goal of valorizing Citrus by-products through targeted agricultural practices. This research contributes to the implementation of targeted agricultural practices (rootstock choice) for the development of high-value Citrus-based products with specific quality traits.

Graphical Abstract

1. Introduction

The Citrus genus species are widely cultivated around the world and are considered to be among the most important fruit crops, supporting both the agricultural and industrial economies of many countries [1]. These evergreen trees produce a wide range of fruits and processed products with important economic and nutritional value [2]. Citrus fruits are rich in bioactive compounds, including ascorbic acid, polyphenols, carotenoids, folic acid, and fibers, all of which contribute to human health and the prevention of chronic diseases [3].
Greece ranks as the third-largest Citrus producer in the EU, following Spain and Italy, with an annual yield of 1,165,000 tons. Citriculture in Greece spans over 41,500 hectares and includes approximately 19 million trees [4]. Citrus cultivation plays a vital role in Greece’s agricultural economy, ranking as the third most important tree crop in terms of economic benefit and cultural heritage, alongside olives and stone fruits. Among the most cultivated Citrus species are oranges, mandarins (clementines), and lemons. Focusing on the group of mandarins, which are mostly cultivated in Greece, 73% of the cultivated trees are clementines (mainly var. SRA 63), 10% are var. Nova (a hybrid of clementine mandarin and Orlando tangelo), 6% are common mandarins (var. Common Chios), and 5% are Ortanique tangerines [4].
Clementine (Citrus clementina Hort. Ex Tan.) (Rutaceae) belongs to the tangerine group of mandarin and is the product of hybridization among Citrus reticulata Blanco (common mandarin) and Citrus sinensis (L.) Osbeck (sweet orange) [5]. Clementines are mainly cultivated across the Mediterranean Citrus belt and are among the most consumed Citrus fruits due to their sweet taste, seedless flesh, and easy-to-peel rind [6,7].
The Citrus market mainly focuses on fresh fruit and juice production, while Citrus, peels, pomace, wastewaters, and even seeds are often discarded and characterized as industrial by-products [8]. These by-products are annually produced in vast quantities and are becoming the center of attention due to the increasing adoption of circular economy practices in citriculture [9]. They represent a significant portion of total unprocessed fruit waste and, in many cases, are disposed of in the environment without any repurposing [10]. This practice can lead to environmental issues, including the degradation of soil quality, fresh-water contamination, and EO toxicity on soil microflora due to the antimicrobial properties of EOs (mainly D-limonene) [11,12].
In Citrus species, EOs occur in almost all plant tissues (rind, flowers, leaves, stems, juice sacks) within oil glands. Citrus EOs are mainly composed of terpenes, sesquiterpenes, aldehydes, alcohols, esters, and sterols. They may also be described as a matrix of hydrocarbons, oxygenated monoterpenes, sesquiterpenes, and non-volatile residues [13,14]. It has been reported that 49 volatile organic compounds have been identified in the peel of the ten most cultivated Citrus species (sweet orange, mandarin, lemon, grapefruit, pummelo, citron, lime, bergamot, bitter orange, yuzu), with most of them (90%) belonging to the group of terpenoids [15]. To date, more than 300 volatile compounds have been detected in various Citrus EOs [16], while some of them exhibit species specificity, a fact which pinpoints their potential use as biomarkers for Citrus species’ identification [15].
Citrus EOs from fruits and peels, due to their pleasant aroma and natural origin, have become key ingredients in industrial formulations of food flavoring, beverages, perfumes, cosmetics, or as factors that cover the undesired taste of medicines [17,18]. Furthermore, Citrus EOs have drawn the attention of many research groups due to their antioxidant [19], antimicrobial, and anti-inflammatory properties [20], which are mainly correlated to their monoterpenes and oxygenated derivatives [21]. It has been stated that the quality of a Citrus EO is determined by the quantity of oxygenated compounds that are found within its volatile fraction [14]. The abundance of these compounds within the EO aromatic profile is influenced by several factors, including environmental stimuli [22], soil fertility [23], the presence of beneficial microorganisms within the root zone [24], the state of fruit immaturity [25], plant tissue sampling [26], the extraction method [27], the scion [15], and the used rootstock [28].
Rootstock selection is one of the most important factors that determine the success of a commercial Citrus grove [29]. In citriculture, trees are propagated via the use of rootstocks and scion cultivars due to the widespread dissemination of Phytopthora gummosis fungal disease in the Citrus belt [30,31]. In the past, the most commonly used Citrus rootstock was sour orange (C. aurantium), which was not only resistant to fungal disease but was also very tolerant to various soil types in the Citrus belt (basic pH, calcareous soils, waterlogging soils, salty soils) [28].
Despite sour orange’s superior traits as a Citrus rootstock, its use gradually declined because mandarin, clementine, orange, and grapefruit trees grafted onto it are sensitive to the Citrus tristeza virus (CTV), which devastated the Citrus belt in the 20th century [31,32]. In the quest for sour orange alternative rootstock, other Citrus genotypes are now used in countries where citriculture is present, such as the ‘Volkamer’ lemon (C. jambhiri), ‘Cleopatra’ mandarin (Citrus reshni), citranges (C. sinensis x Poncirus trifoliata), citrumelo (C. paradisi x P. trifoliata), and ‘Ranpur’ lime or ‘Alemow’ (C. macrophylla), with all of them being tolerant to CTV [28]. The use of rootstock allows Citrus trees to adapt to abiotic stresses (drought, salinity, cold), resistance to tree pathogens, as well as the modulation of growth habit, fruit set, flowering time, fruit yield, fruit quality, nutrient uptake, and leaf photosynthetic activity [13,33,34]. Furthermore, it has been demonstrated that the rootstock can affect Citrus peel, flower, and leaf EO composition [28,35,36,37]. The direct effect of rootstock on the volatile compound profile in various plant tissues, as well as on fruit quality, is governed by specific interactions involving water relations, mineral distribution, and phytohormone signaling between the rootstock and the grafted scion, which are further influenced by prevailing microclimatic conditions [29,38].
In the framework of our overall studies on the chemical profile of the EOs from Citrus species grown in Greece [26,35,39], an in-depth analysis of EOs obtained via the hydrodistillation of peels and leaves from clementine mandarin var. SRA 63, cultivated in the national germplasm bank of the Arboricultural Station of Poros (South Greece), is reported herein. Most of the existing studies on C. clementina EOs focus on monitoring the volatile profile of peels and fruits [40,41], while only a few provide data regarding the chemical composition of clementine leaf oil [42]. Furthermore, there are no reports that provide data on the impact of rootstock choice on the chemical profile of SRA 63, cultivated in Greece. Our study focused on the four most commonly used rootstocks (Cleopatra mandarin, sour orange, Troyer citranges, and Swingle citrumelo), which are used in the Greek citriculture [31]. The scope of the present work was to evaluate and support the hypothesis that rootstock choice exerts an impact on the phytochemical profile of the EOs in clementine mandarin peels and leaves. The findings of this study could provide valuable insights into the potential valorization of other Citrus species as well.

2. Materials and Methods

2.1. Plant Material and Extraction of EOs

The plant material used in the present study was obtained from the Citrus orchard of the Arboricultural Station of Poros, South Greece (latitude 37.4990° N, longitude 23.4522° E, Mediterranean climate, yearly average temperature 22 °C, and average rainfall of 31.81 mm per month). In the current experiment, tree spacing was 4 m × 6 m. The soil of the Citrus grove was sandy loam, well drained with pH 6.5, and contained 1.9% of CaCO3.
Samples of leaves and fruit were collected from five random 25-year-old clementine (C. clementina) SRA 63 cultivar, grafted upon four rootstocks: ‘Cleopatra’ mandarin—Citrus reshni Hort ex. Tanaka—(R1), sour orange—Citrus aurantium L.—(R2), ‘Troyer’ citrange—Citrus sinensis L. Osbeck x Poncirus trifoliata L. Raf.—(R3), and Swingle citrumelo—Citrus paradisi Macf × Poncirus trifoliata (L.) Raf.—(R4). The leaf samples were taken from the middle of the shoots, from all four directions of the tree, from the mid-height of the canopy, and at the reproducing stage S10 (mature and ripe stage) [43]. All trees were cultivated in the same grove, during the period 2022–2023, under the same climatic conditions. All trees received the same cultivation practices, were irrigated via drip irrigation from May to October with irrigation water of low Na+, Co−, and B− ions content, with 0.63 mMhos and fertilized with 21-0-0, 0-20-0, and 0-0-50, which each contains 0.01, 0.06, and 0.1 units of N, P, and K, respectively.
Citrus fruit and leaves were collected at the time of harvest (November 2023). All clementine fruits were of similar size, shape, and color without any visible marks. The collected leaves were fully mature. Overall, 50 fruits and 100 leaves (10 fruits and 20 leaves per tree of similar developmental stage) were picked from equally allocated places of the tree canopy. The mean value of the water content of the sampled leaves from all treatments was 90.1%, while the mean value of the water content of the fruit was 86.40%.
The hand-picked fruits were split into 6 segments, and the flesh was removed from the peel (albedo and flavedo). Afterwards, the peel’s albedo tissue was carefully separated by hand and discarded. Following this procedure, 250 g of fruit peel (flavedo tissue) and 100 g of mature leaves were cut into smaller pieces and immediately subjected to hydrodistillation by using 1 L of distilled water for 3 h using a Clevenger-type apparatus. The obtained EO of each tissue was collected in n-pentane (≥99%, Carlo Erba Reagents, France), dried over anhydrous sodium sulfate (Na2SO4) (Lach-Ner, s.r.o., Neratovice, Czech Republic), and stored at 4–6 °C in dark glass amber vials until further analysis [35]. All analyses were performed within a week after the EO extraction. The moisture content of the mandarin peel was also estimated, via air drying at 80 °C, for 75 min [44].

2.2. Gas Chromatography–Mass Spectroscopy (GC-MS) Analysis

The EO compositions were analyzed using gas chromatography–mass spectrometry (GC-MS). The analysis was conducted with an Agilent Technologies 7820A gas chromatograph, coupled to an Agilent Technologies 5977B mass spectrometer (Agilent, Santa Clara, CA, USA), operating with electron impact (EI) ionization at 70 eV. The gas chromatograph featured a split/splitless injector and an HP5MS capillary column (30 m in length, 0.25 mm internal diameter, and 0.25 μm film thickness). The temperature program began at 60 °C for 5 min, followed by an increase of 3 °C/min until reaching 280 °C, where it was retained for 15 min. The total run time for the analysis was 93 min. Helium was used as the carrier gas at a flow rate of 0.7 mL/min, with an injection volume of 2 μL, a split ratio of 1:10, and an injector temperature of 280 °C.
The Kovats retention index (RI) values were determined using a homologous series of n-alkanes (C8–C23). Compound identification was achieved by comparing the mass spectra and retention times with reference libraries (Wiley Registry of Mass Spectral Data) and further verified by matching Kovats retention indices (KIs) with the published data [45]. All samples were analyzed in triplicate and the relative proportions of essential oil components were calculated as mean values of the percentages using peak area normalization, assuming all relative response factors as one. Data analysis was performed using MSD ChemStation (version F 01.03.2357).

3. Results

3.1. Isolation and Yields of EOs

The obtained EOs from the peels and leaves from clementine/rootstock combinations—SRA 63/Cleopatra (S-R1); SRA63/sour orange (S-R2); SRA 63/Troyer (S-R3); and SRA 63/Swingle citrumelo (S-R4)—had a light-yellow color and the characteristic pleasant clementine mandarin odor, with yields (%) (expressed as ml per 100 g of fresh tissue) presented in Table 1. The peel moisture content, calculated on a wet basis, ranged from 79.20 to 79.23%.

3.2. Chemical Composition of Clementine Peel EOs

The clementine peel EOs presented a variable qualitative chemical profile, with a total number of fifty compounds being identified by GC-MS (Table 2). The volatiles were chemically categorized into monoterpenoids, sesquiterpenoids (hydrocarbons—MHs, SHs—and oxygenated compounds—OMs, OSs), fatty acids, aldehydes, alcohols, and esters. The relative concentration of each chemical group among the different clementine/rootstock combinations is presented in Table 3.

3.3. Chemical Composition of Clementine Leaves’ EOs

The EOs obtained from the leaves presented a diverse profile, with a total number of fifty-four compounds identified in the studied clementine mandarin/rootstock combinations (95.08–93.19%) by GC-MS (Table 4). The relative concentration of each chemical group among the different clementine/rootstock combinations is presented in Table 5.

4. Discussion

4.1. Yields of EOs

As presented in Table 1, the EO yield from peels ranged from 0.25 to 0.83 mL/100 g, with the lowest yield recorded in the S-R1 and the highest in S-R2. The EO yield from leaves varied between 0.43 and 1.00 mL/100 g, with the lowest yield observed in the S-R4 and the highest in S-R3. The choice of rootstock plays a significant role in the yield of essential oils, as demonstrated in various studies. For example, Türkmen et al. [46] found that essential oil yields from the peels of Rio Red grapefruit grafted onto different rootstocks ranged from 0.5% to 1.5%, with Smooth Flat Seville sour orange producing the highest yield. Similarly, Ferrer et al. [28] reported significant variations in the peel essential oil yields of Navelina sweet orange grafted onto different rootstocks, ranging from 5.50 g/100 g dry peel for FLHORAG1 to 7.72 g/100 g dry peel for Carrizo citrange.

4.2. Analysis of Clementine Peel EOs

The detected metabolites included eight MHs, seventeen OMs, ten SHs, six OSs, two fatty acids, five aldehydes, one alcohol, and one ester. Among the tested clementine SRA 63/rootstock combinations, the S-R3 produced fruits whose peel had the richest chemical profile with forty-two constituents, followed by S-R2 with thirty-eight, S-R4 with twenty-four, and S-R1 with twenty-one. Our data highlight the fact that the rootstock choice influences the qualitative chemical profile of the clementine peel, since the use of R2 and R3 almost doubled the amount of detected chemical compounds compared to R1 or R4.
Regardless of rootstock choice, the clementine peel EOs contained limonene, α-terpineol, myrcene, linalool, and α-pinene as the most abundant compounds, followed by minor amounts of sabinene, terpinene-4-ol, α-sinensal, n-octanal, γ-terpene, citronellal, carveol, 2,8-trans-p-mentadien-1-ol, α-copaene, germacrene-D, and carvone. These data support the fact that these compounds dominate in the peel of Citrus EOs [47].
Limonene was the dominant component in all of the samples studied, ranging from 82.45% (S-R4) to 56.47% (S-R3). These data are in accordance with previous studies that highlight the dominance of limonene in Citrus fruits [48,49,50]. According to our results, the fruit peel of clementine, when grafted upon R4, had 5.60%, 16.62%, and 42.38% more limonene compared to the peel of fruits obtained from trees grafted upon R1, R2, or R3, respectively. Several scientific studies have investigated the influence of rootstock choice on the volatile composition of Citrus fruits, including limonene content in mandarins and other Citrus species. In the work of Forner-Giner et al. [51] the researchers demonstrated that rootstock choice significantly influenced the limonene concentration in ‘Clemenules’ mandarin juice, with rootstocks such as ‘Carrizo citranges’ and ‘Forner—Alcaide 517’ leading to higher contents. Also, in the work of Georgiou et al. [52] the use of ‘Troyer citranges’ rootstock resulted in the highest limonene content in the peel of ‘Fremont’ mandarin fruits. Furthermore, in the work of Aguilar-Hernandez et al. [24] rootstock choice affected the total volatile profile of the lemon peel EOs, including limonene levels, with the Forner—Alcaide series exhibiting elevated portions of limonene compared to sour orange rootstock.
Apart from limonene, the use of R3 favored the abundance of α-terpinol in the peel of the clementine fruit, since an amount of 13.24% was detected, compared to the 3.1% and 3.19% levels when R1 or R2 was used, respectively, while the use of R4 limited the portion of this volatile compound (0.59%). The use of R3 or R1 did not influence the abundance levels of myrcene in the fruit peel, but an 84% or 35.03% increase was witnessed when R2 or R4 was used, respectively. The use of R1, R2, or R3 increased the abundance of linalool in the peel of clementine fruits compared to R4 by 118.25%, 102.48%, and 55.60%, respectively. Additionally, the use of R2 and R3 almost doubled the relative concentration of α-pinene in the fruit peel compared to the S-R1 and S-R4 combinations. Our results are in accordance with those previously obtained by Forner-Giner et al. [51] Darjazi [53], Aguilar-Hernandez et al. [24], and Ferrer et al. [28], who demonstrated that Citrus rootstock choice strongly influences the amount of volatile monoterpene hydrocarbons in Citrus peel.
Regarding the abundance of sesquiterpenes in the fruit peel, the use of R1 promoted the biosynthesis of trace amounts of only five compounds, namely α-sinensal (0.2%), α-copaene (0.16%), caryophyllene oxide (0.14%), germacrene D (0.13%), and α-cadinol (0.12%). The use of R2 favored the biosynthesis of ten compounds, with the most abounded being α-sinensal (1.1%), δ-cadinene (0.4%), followed by α-copaene (0.25%), T-muurolol (0.19%), and germacrene D (0.17%). Minor portions of β-copaene, valencene, α-humulene, and elemol were also detected. Interestingly, the use of R3 favored the biosynthesis of trace amounts of fourteen sesquiterpenes (hydrocarbon and oxygenated) in the matrix of the clementine peel, with the most abounded being α-sinensal (1.37%), δ-cadinene (0.65%), followed by germacrene D (0.39%) and α-copaene (0.39%). Valencene (0.27%), γ-eudesmol (0.25%), γ-cadinene (0.24%), α-farnesene (0.23%), trans-α-bergamotene (0.23%), and β-elemene (0.22%) were also detected in the peel of clementine fruits grafted upon R3, along with a minor amount of elemol, α-cadinol, caryophyllene oxide, and β-copaene (0.15–0.12%). The use of R4 favored the biosynthesis of only eight sesquiterpenes, in the peel of the clementine fruit, with the most abundant being α-sinensal (0.47%), δ-cadinene (0.27%), followed by germacrene D (0.2%), α-copaene (0.19%), β-copaene (0.13%), elemol (0.12%), and trace amounts of β-elemene and α-farnesene (0.09%). Our results indicate and support the proposed effect that the rootstock choice strongly affects the production of sesquiterpenes (especially SHs) in the peel of mandarin fruit, with R3 exerting a strong effect in terms of chemical composition and quantity levels [54].
Furthermore, our data indicate that the rootstock choice poses a direct influence upon the distribution of compounds among the identified chemical groups in the peel of clementine fruits (Figure 1). The use of R1 favored the biosynthesis of mainly MHs in the peel (86.88%), followed by OMs (10.10%), and significantly lower amounts of OSs (0.46%) and SHs (0.29%), as well as alcohols (0.51%). In the fruits harvested from clementine trees grafted upon R2, the chemical groups of MHs (78.67%), OMs (12.7%), OSs (1.59%), SHs (1.24%), aldehydes (2.46%), alcohols (0.91%), and esters (0.15%) were identified, witnessing the additional biosynthesis of aldehydes and esters compared to R1 usage. Interestingly, S-R3 peel EOs exhibited the greatest chemical diversity among the tested combinations with MHs (64.44.%); OMs (23.11%); SHs (2.74%); OSs (2.05%); aldehydes (2.29%); alcohols (0.85%); esters (0.24%) and, additionally, fatty acids (0.53%) that were not detected in the EOs of the other combinations. Furthermore, when R4 was used, analysis of the peel EOs revealed the existence of six chemical groups, with the dominant being MHs (91.75%), followed by OMs (4.3%), aldehydes (1.31%), SHs (0.97%), OSs (0.59%), and alcohols (0.15%).
These data clearly indicate that the rootstock choice of R4 strongly influenced the biosynthesis of MHs in the peel of the fruit since an increase of 42.38%, 16.62%, and 5.60% of the presence of these compounds was witnessed, compared to the usage of R3, R2, and R1, respectively. Also, the use of R4 strongly influenced the amount of OMs which are synthesized into the peel of the fruit, since a decrease of 81.39% or 66.14% or 57.42% was witnessed, compared to R3, R2, or R1, respectively. Additionally, our data indicated that the use of R3 strongly influences the biosynthesis of MHs within the peel of the fruit since a decrease of 29.76% or 25.82% or 18.08% was witnessed, compared to R4, R1, or R2, respectively. The latter influence of R3 is furthermore supported by the fact that in this rootstock, the biosynthesis of OMs, SHs, and OSs was favored compared to the other tested rootstocks in the present work.
The diversity and ratio of hydrocarbons to oxygenated compounds are crucial to the character of essential oils. Oxygenated compounds, though not always the most abundant, strongly influence the sensory properties and overall quality of the oils. This effect is evident when Citrus essential oils are exposed to sunlight, UV radiation, or air, which can alter their volatile profiles through chemical reactions [15]. For instance, in Citrus grandis oil, aldehydes like decanal, dodecanal, neral, and geranial decrease significantly under such conditions, while compounds such as β-citronellal, α-humulene, linalool oxides, limonene oxides, carveols, perilla alcohol, carvone, and various oxides increase or newly appear. This aldehyde transformation shifts the aroma by enhancing strong oily notes and reducing fresh notes, thereby modifying the oil’s quality profile [15].
Regarding aldehydes, our results indicate that the use of R1 did not favor the biosynthesis of this chemical group in the peel of clementine fruit. The use of R2 influenced the biosynthesis of decanal (1.92%) and minor levels of 2,4-decadienal, trans-2-decenal, dodecanal, and trans-2-dodecenal (0.12–0.17%) in the peel of the tested samples. Interestingly, the use of R3 promoted the biosynthesis of decanal (0.94%) and dodecanal (0.63%) and minor levels of trans-2-decenal, 2,4-decadienal, and trans-2-dodecenal (0.22–0.29%). The use of R4 did not favor the biosynthesis of this chemical group in the peel of the fruits since only decanal (1%) and trans-2-dodecenal (0.31%) were detected. Our results highlight the fact that rootstock choice poses a direct effect upon the biosynthesis of aldehydes, and, more specifically, the use of R2 increased the amount of decanal in the peel of clementine fruit by 104.25% compared to the peel from fruits grafted upon R3. It has been previously stated that non-terpenoid compounds such as aldehydes, although present at low abundance compared to the other components, have a potential impact on the aroma and overall quality of the essential oils and can contribute unique sensory characteristics that differentiate the oils from one another [15]. For example, certain Citrus species, such as C. reticulata, have been noted for their higher concentrations of non-terpenoid aldehydes, which can help distinguish them from other species [15].
Concerning the amount of minor metabolites of the group of esters, fatty acids, and alcohols in the EO fraction of the peel of clementine fruit, the use of R1 did not promote the biosynthesis of esters and fatty acids. The use of R2 favored the biosynthesis of the ester octanol acetate (0.15%) and of n-octanol (0.91%), with the latter achieving an increase of 78.43% compared to the S-R1 combination. Furthermore, the use of R3 had a positive impact upon the biosynthesis of minor amounts of octanol acetate (0.24%), dodecanoic acid (0.32%), hexadecanoic acid (0.21%), and alcohols (0.85%), with the latter corresponding to an increase of 66.66% compared to the amount being produced when R1 was used. Also, the use of R4 did not favor the biosynthesis of esters and fatty acids, and only a minor portion of n-octanol (0.15%) was detected.
The results in the present study show that rootstock choice strongly influences the chemical profile of the EOs from the peel of clementine SRA 63, with R1 and R4 favoring the biosynthesis of limonene. The use of R3 favors the biosynthesis of α-terpineol and other oxygenated compounds, such as α-sinensal and aldehydes (Table 1). The influence of rootstock choice on the chemical profile of EOs in Citrus fruit peel could be attributed to the degree of compatibility between the scion and the rootstock, which clearly influences the movement of water, nutrients, phytohormones, and carbohydrates via the graft union [24].

4.3. Analysis of Clementine Leaves’ EOs

The chemical profile of the leaves’ EOs was sorted into five main chemical groups: MHs (13); OMs (20); SHs (11); OSs (9); and aldehydes (1). Among the tested clementine SRA 63/rootstock combinations, S-R2 favored the biosynthesis of forty-four constituents, followed by S-R3 with thirty-nine, S-R4 with thirty-six, and S-R1 with twenty-five. Our data highlight the fact that rootstock choice influences the qualitative chemical profile of the clementine leaves’ EOs since the use of R2, R3, and R4 enhanced the biosynthesis of more than ten compounds compared to R1, a fact that was also witnessed in the peel of the fruits.
The most abundant compounds in the leaves’ EOs of clementine, independently of the rootstock used, were sabinene (16.23–28.40%), linalool (5.62–14.68%), limonene (6.42–17.38%), δ-2-carene (5.49–7.65%), β-sinensal (5.82–8.51%), trans-β-ocimene (0.94–8.31%), myrcene (2.62–4.39%), α-sinensal (7.49–0.20%), terpineol-4-ol (4.55–1.92%), α-pinene (1.7–6.25%), and β-caryophyllene (2.61–1.37%). These compounds were followed by minor amounts of terpinolene (0.35–2.43%), citronellol 0.20–1.84%), geranyl acetate (0.44–1.25%), and trans-β-farnesene (0.31–1.2%).
Our results are in accordance with previous studies that identified sabinene, linalool, limonene, δ-3-carene, and trans-β-ocimene as key constituents of the clementine mandarin leaves’ EO profile [6,55]. In our study, sabinene and linalool were identified as the two major components of the EOs from the leaves of clementine, a fact that supports the dominance of these compounds in that Citrus species (clementine mandarins).
Sabinene was the dominant component in all samples, reaching values from 28.40% in the leaves of S-R4 and 21.71% in S-R1 to 17.99% in the leaves of S-R2 and 16.23% in S-R3. These data are in accordance with previous studies that highlight the dominance of sabinene in the leaves of clementine [56,57]. According to our results, the EOs of S-R4 leaves had 74.98%, 57.86%, and 30.81% more sabinene compared to S-R3, S-R2, or S-R1, respectively. This supports the fact that the chemical composition of EOs extracted from mandarin leaves is influenced by rootstock choice, since there is a variance regarding the relative concentration of volatiles in the leaves. For example, the work of Darjazi [36] revealed that rootstock choice (Swingle citrumelo or yuzu) can lead to higher concentrations of aldehydes and alcohols in the leaf essential oil of the cv. ‘Page’ mandarin hybrid. Furthermore, it has been stated that Citrus rootstock choice does influence the primary and secondary metabolites of Citrus scion, a fact that could consequently provide tolerance to pathogens [58]. Regarding linalool, S-R3 and S-R2 did not influence its abundance levels in the leaves’ EO, but a decrease of 17.50% or 61.71% was witnessed when R1 or R4 was used compared to R3.
Furthermore, the use of R3 favored the abundance of limonene in the leaves’ EO of clementine trees, since a relative amount of 17.38% was detected, compared to the 6.42%, 10.41%, and 13.19% levels when R4, R1, or R2 was used, respectively. It has to be stated that even though limonene is the major component in many Citrus peels, its prevalence in leaf essential oil is less consistent. For example, leaf EO from lemons (Citrus limon L.) is rich in limonene, geranial, neral, and citronellal [59]. In contrast, the leaf EO from sour orange (Citrus aurantium L.) contains significant amounts of linalool acetate, α-terpinyl acetate, linalool, and eucalyptol [60], while the leaf EO of kaffir lime (Citrus hystrix L.) is predominantly composed of (S)-citronellal, accounting for up to 80%, and a minor amount of citronellol, nerol, and limonene [61]. These variations, in parallel with our data, highlight the fact that the chemical composition of Citrus leaf EO could be characterized as species-dependent and could be used as a marker to support the identification of various Citrus species [62,63].
The use of R1, R2, or R4 did not influence the abundance levels of δ-2-carene, but a 28.23% decrease was witnessed when R3 was used compared to R1. Furthermore, the use of R1 and R2 did not influence the levels of trans-β-ocimene, showing similar relative concentrations (6.53–6.51%). Interestingly, an 85.60% decrease was witnessed when R3 was used, and a significant increase of 27.25% was also found with the use of R4 compared to R2. Additionally, the use of R1 and R4 favored the biosynthesis of β-sinensal (8.51%; 7.82%, respectively) in the volatile profile of the leaves’ EO of clementine compared to R2 or R3 use, where amounts of 5.82% and 5.87%, respectively, were detected. Concerning α-sinsenal, the use of R1 enhanced the relative abundance of the compound in the leaves (7.49%). Our results support the work of Türkmen et al. [46] who demonstrated that rootstock choice influences the dominance of specific monoterpenes and sesquiterpenes (sabinene or β-sinensal) in the essential oil composition in the leaf of Rio Red grapefruit.
It is worth noting that the use of R2 favored the biosynthesis of a total number of forty-four volatile compounds in the leaves’ EO compared to only twenty-five compounds observed when Cleopatra rootstock was used.
Regarding the abundance of sesquiterpenes in clementine tree leaves, the use of R1 promoted the biosynthesis of β-caryophyllene (2.61%) compared to R4 (1.45%), R2 (1.37%), or R3 (1.84%). Furthermore, the use of R3 favored the biosynthesis of trans-β-farnesene (1.2%) in the EOs’ matrix compared to the amount produced when R1 (0.79%), R4 (0.66%), or R2 (0.31%) was used. Interestingly, S-R3 leaves’ EO composition exhibited increased levels of caryophyllene oxide (2.55%) in comparison with the minor amount witnessed in S-R2 (0.32%), the trace amount (0.07%) in S-R4, and the absence in S-R1. It is noteworthy that S-R1 favored the biosynthesis of only four sesquiterpenes in the leaves’ EO matrix, while the use of R2, R4, or R3 favored the biosynthesis of sixteen, fifteen, or twelve sesquiterpenes, respectively.
Regardless of rootstock choice, and similarly to peels’ EO, the leaf EO of clementine is primarily composed of monoterpenoids (hydrocarbons and oxygenated). However, the use of R2 and R3 resulted in higher OM biosynthesis compared to R1 and R4, with R2 and R3 producing 28% and 32% OMs, respectively, while R1 and R4 yielded 22% and 14.7% (Figure 2). The use of R1 had the most profound effect upon the leaf EOs’ total sesquiterpenoids since it favored the biosynthesis of a total amount of 20.41%, a 95.12% increase when compared to S-R2 (10.46%), a 35.97% increase when compared to S-R3 (15.01%), and a 63.14% increase when compared to S-R4. Furthermore, in all of the examined leaves’ EOs, OSs were significantly more abundant than the respective SHs. Our results also demonstrated that only the use of R3 promoted the biosynthesis of aldehyde decanal (0.89%) in the leaf EO of clementine, supporting its influence in the biosynthesis of volatile compounds in the leaves of the scion.
Our data further support the fact that rootstock choice can influence the chemical profile of the volatiles in the EOs from Citrus leaves [37,46,64]. This latter influence could be attributed to various physiological, biochemical, and molecular interactions between the scion and the rootstock. A potent mode of action could be linked with the ability of the rootstock to absorb and translocate nutrients and water from the soil [65]. Another potent mode of action could be associated with the rootstocks to alter the levels of phytohormones such as abscisic acid (ABA), jasmonic acid (JA), and salicylic acid (SA), which are involved in plant defense cascade and aroma compound biosynthesis via the regulation of terpene synthases (TPS genes) [66]. Furthermore, rootstock choice can pose a direct influence on scion gene expression via the movement of mRNA and small interfering RNAs (siRNAs) across the graft union. The latter could regulate the transcription of the genes involved in volatile organic compounds’ biosynthesis in the scion leaves [67].
Finally, it is important to emphasize that the choice of rootstock and the resulting variations in volatile profiles can have significant implications for the food, pharmaceutical, cosmeceutical, and agriculture industries due to the diverse chemotypes and biologically active compounds present in Citrus EOs. For example, limonene has been recognized for its antimicrobial and food preservative properties [17,68], while the peel EO of Citrus sinensis (sweet orange), rich in limonene, has been shown to increase the mortality rates of various herbivore insects, indicating a direct link between limonene content and pesticidal effectiveness [69]. Additionally, compounds such as citral, geranial, citronellol, linalool, and myrcene possess antifungal properties important for the food industry, as fungal growth is a leading cause of food spoilage and economic losses [17]. Furthermore, a diverse chemical profile of Citrus EOs —including both oxygenated and hydrocarbon terpenoids—is often more desirable, as such complexity enhances aroma appeal and suitability for various applications in the fragrance and flavor industries [68].

5. Conclusions

The present study demonstrates that rootstock selection significantly alters the qualitative and quantitative composition of essential oils in both the peel and leaves of clementine mandarin var. SRA 63 cultivated in Greece. Among the tested rootstocks, clear patterns emerged: Cleopatra mandarin and Swingle citrumelo enhanced limonene production in the peel, while Troyer citrange promoted the biosynthesis of a broader spectrum of volatiles, including oxygenated monoterpenes, sesquiterpenes, and aldehydes. In leaf EO, sabinene, linalool, and limonene were dominant across all rootstocks, although their concentrations varied notably.
These findings highlight the pivotal role played by rootstock in modulating secondary metabolism through physiological, biochemical, and potentially molecular interactions with the scion. The data support the strategic use of rootstock not only to improve agronomic performance but also to optimize essential oil composition for industrial and pharmaceutical applications. Overall, this study confirms that rootstock choice is a key factor in shaping the phytochemical profile of Citrus essential oils, with important implications for breeding programs, quality optimization, and the valorization of Citrus by-products in agro-industrial systems.

Author Contributions

Conceptualization, V.Z. and I.C.; methodology, E.P., K.G. and I.C.; validation, E.P. and K.G.; formal analysis, E.P. and K.G.; investigation, E.P., K.G., C.G. and E.N.; data curation, E.P., K.G., C.G. and E.N.; writing—original draft preparation, V.Z. and E.P.; writing—review and editing, E.P., K.G. and I.C.; supervision, I.C.; project administration, V.Z. and I.C. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Data Availability Statement

The original contributions presented in this study are included in the article. Further inquiries can be directed to the corresponding author.

Acknowledgments

The authors thank the staff of the Arboricultural Station of Poros (Hellenic Ministry of Rural Development and Food, Greece) for their help with the sampling of the material.

Conflicts of Interest

The authors declare no conflicts of interest.

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Horticulturae 11 00523 g001
Figure 1. Pie charts illustrating the chemical groups and their relative concentrations in the peel EOs of clementine grafted onto rootstocks R1–R4.
Figure 1. Pie charts illustrating the chemical groups and their relative concentrations in the peel EOs of clementine grafted onto rootstocks R1–R4.
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Horticulturae 11 00523 g002
Figure 2. Pie charts illustrating the chemical groups and their relative concentrations in the leaf EOs of clementine grafted onto rootstocks R1–R4.
Figure 2. Pie charts illustrating the chemical groups and their relative concentrations in the leaf EOs of clementine grafted onto rootstocks R1–R4.
Horticulturae 11 00523 g002
Table 1. Yields % (v/w) of the peel and leaf EOs from cv SRA 63 clementine mandarin grafted upon four different rootstocks.
Table 1. Yields % (v/w) of the peel and leaf EOs from cv SRA 63 clementine mandarin grafted upon four different rootstocks.
S-R1S-R2S-R3S-R4
Peels’ EO (%, v/w)0.250.830.620.40
Leaves’ EO (%, v/w)0.910.671.200.43
Table 2. Volatiles of the peel’s EOs from clementine mandarin var. SRA 63 grafted upon four different rootstocks, expressed as peak area percentage.
Table 2. Volatiles of the peel’s EOs from clementine mandarin var. SRA 63 grafted upon four different rootstocks, expressed as peak area percentage.
Chemical GroupCompoundsKIS-R1S-R2S-R3 S-R4
MHsα-pinene9391.26 ± 0.123.18 ± 0.132.47 ± 0.191.36 ± 0.11
MHssabinene9750.43 ± 0.030.79 ± 0.06-1.52 ± 0.12
MHsmyrcene9914.53 ± 0.188.34 ± 0.334.51 ± 0.186.09 ± 0.24
MHsα-terpinene10170.11 ± 0.01---
MHslimonene102980.37 ± 1.6165.63 ± 1.3156.47 ± 1.1382.45 ± 2.01
MHstrans-β-ocimene1050-0.24 ± 0.05-0.10 ± 0.01
MHsγ-terpinene10600.18 ± 0.010.49 ± 0.010.53 ± 0.020.23 ± 0.02
Alcoholn-octanol10680.51 ± 0.040.91 ± 0.060.85 ± 0.070.15 ± 0.03
OMslinalool oxide10870.28 ± 0.020.67 ± 0.04--
OMsterpinolene1089-0.22 ± 0.010.69 ± 0.080.11 ± 0.00
OMslinalool10975.26 ± 0.214.88 ± 0.303.75 ± 0.152.41 ± 0.50
MHs1,3,8-p-menthatriene1110--0.46 ± 0.06-
OMs2,8-trans-p-menthadien-1-ol11230.19 ± 0.100.23 ± 0.020.47 ± 0.04-
OMslimonene oxide11370.18 ± 0.000.11 ± 0.00--
OMsβ-terpineol1144--0.38 ± 0.02-
OMscitronellal11530.38 ± 0.010.37 ± 0.070.35 ± 0.010.26 ± 0.08
OMsterpinen-4-ol11770.35 ± 0.011.06 ± 0.111.31 ± 0.030.60 ± 0.00
OMsα-terpineol11893.1 ± 0.673.19 ± 0.1813.24 ± 0.120.59 ± 0.03
Aldehydedecanal1202-1.92 ± 0.040.94 ± 0.011.00 ± 0.00
Esteroctanol acetate1214-0.15 ± 0.000.24 ± 0.07-
OMstrans-carveol1217--0.81 ± 0.02-
OMscitronellol1226-0.49 ± 0.010.76 ± 0.040.10 ± 0.03
OMscis-carveol12290.21 ± 0.050.54 ± 0.030.33 ± 0.01-
OMscarvone12430.15 ± 0.000.18 ± 0.120.32 ± 0.03-
OMsgeraniol1253-0.12 ± 0.030.17 ± 0.06-
Aldehydetrans-2-decenal1264-0.13 ± 0.050.21 ± 0.00-
OMsperillaldehyde1272-0.42 ± 0.02-0.23 ± 0.03
OMslimonen-10-ol1290-0.11 ± 0.120.28 ± 0.01-
Aldehyde2,4-decadienal1317-0.17 ± 0.060.29 ± 0.01-
OMsα-terpinyl acetate1349-0.11 ± 0.020.25 ± 0.03-
SHsα-copaene13770.16 ± 0.070.25 ± 0.040.39 ± 0.090.19 ± 0.03
SHsβ-elemene1391--0.22 ± 0.110.09 ± 0.02
Aldehydedodecanal1409-0.12 ± 0.020.63 ± 0.04-
SHsβ-copaene1432-0.15 ± 0.010.12 ± 0.030.13 ± 0.01
SHstrans-α-bergamotene1435--0.23 ± 0.14-
SHsα-humulene1455-0.13 ± 0.04--
Aldehydetrans-2-dodecenal1466-0.12 ± 0.010.22 ± 0.040.31 ± 0.04
SHs germacrene D14850.13 ± 0.000.17 ± 0.040.39 ± 0.010.20 ± 0.02
SHsvalencene1496-0.14 ± 0.050.27 ± 0.05
SHsα-farnesene1506--0.23 ± 0.010.09 ± 0.02
SHsγ-cadinene1514--0.24 ± 0.09-
SHsδ-cadinene1523-0.4 ± 0.010.65 ± 0.020.27 ± 0.13
OSselemol1550-0.12 ± 0.000.15 ± 0.020.12 ± 0.01
Fatty Aciddodecanoic acid1567--0.32 ± 0.03-
OSscaryophyllene oxide15830.14 ± 0.05-0.14 ± 0.03-
OSsγ-eudesmol 1632-0.18 ± 0.010.25 ± 0.10-
OSsα-cadinol16540.12 ± 0.06-0.14 ± 0.02-
OSsT-muurolol1646-0.19 ± 0.01--
OSsα-sinensal17570.2 ± 0.031.1 ± 0.021.37 ± 0.060.47 ± 0.06
Fatty Acidhexadecanoic acid1922--0.21 ± 0.03-
Total97.897.7296.2599.07
-: not detected, MHs: monoterpene hydrocarbons, OMs: oxygenated monoterpenes, SHs: sesquiterpene hydrocarbons, OSs: oxygenated sesquiterpenes.
Table 3. Chemical groups and relative concentrations (area %) of the studied EOs from the peel of clementine mandarin var. SRA 63 per rootstock combination.
Table 3. Chemical groups and relative concentrations (area %) of the studied EOs from the peel of clementine mandarin var. SRA 63 per rootstock combination.
Chemical GroupsRelative Concentration (Area %)
S-R1S-R2S-R3 S-R4
MHs86.8878.6764.4491.75
OMs10.112.723.114.3
SHs0.291.242.740.97
OSs0.461.592.050.59
Aldehydes-2.462.291.31
Alcohols0.510.910.850.15
Esters-0.150.24-
Fatty acids--0.53-
-: not detected.
Table 4. Volatiles of the leaves from clementine mandarin var. SRA 63 grafted upon different rootstocks, expressed as peak area percentage.
Table 4. Volatiles of the leaves from clementine mandarin var. SRA 63 grafted upon different rootstocks, expressed as peak area percentage.
Chemical GroupCompoundsKIS-R1S-R2S-R3S-R4
MHsα-thujene9300.35 ± 0.120.59 ± 0.090.42 ± 0.16-
MHsα-pinene9391.7 ± 0.012.49 ± 0.162.25 ± 0.076.25 ± 0.35
MHscamphene954-0.14 ± 0.030.15 ± 0.05-
MHssabinene97521.71 ± 1.0817.99 ± 1.0616.23 ± 0.0728.40 ± 1.84
MHsmyrcene9913.49 ± 0.153.86 ± 0.212.62 ± 0.364.39 ± 0.08
MHsα-phellandrene10030.72 ± 0.050.77 ± 0.02--
MHsδ-2-carene10027.65 ± 0.667.45 ± 0.185.49 ± 1.657.32 ± 0.22
MHsα-terpinene10170.41 ± 0.020.67 ± 0.020.12 ± 0.031.81 ± 0.00
MHsp-cymene10250.35 ± 0.030.48 ± 0.01--
MHslimonene102910.41 ± 1.0013.19 ± 1.2917.38 ± 1.046.42 ± 0.93
MHscis-ocimene1034-0.49 ± 0.05-0.55
MHstrans-β-ocimene10506.15 ± 0.066.53 ± 0.510.94 ± 0.118.31 ± 0.29
MHsγ-terpinene10601.05 ± 0.041.5 ± 0.090.2 ± 0.082.49 ± 0.17
OMscis-sabinene hydrate10700.61 ± 0.02--0.74 ± 0.05
OMstrans-linalool oxide1073--0.82 ± 0.04-
OMscis-linalool oxide1087--0.76 ± 0.01-
OMsterpinolene10891.55 ± 0.022.36 ± 0.510.35 ± 0.042.43 ± 0.41
OMslinalool109712.11 ± 1.2014.42 ± 0.9814.68 ± 0.815.62 ± 0.16
OMstrans-sabinene hydrate1098-0.88 ± 0.031.15 ± 0.070.22 ± 0.01
OMscis-p-menth-2-en-1-ol1122---0.22 ± 0.01
OMstrans-p-menth-2-en-1-ol1140---0.11 ± 0.02
OMs1-terpineol1134-0.16 ± 0.03--
OMslimonene oxide1142-0.49 ± 0.071.15 ± 0.09-
OMscitronellal11532.33 ± 0.141.71 ± 0.224.31 ± 1.071.12 ± 0.09
OMsterpinen-4-ol11771.92 ± 0.204.55 ± 0.361.92 ± 0.153.24 ± 0.55
OMsp-cymen-8-ol1183-0.29 ± 0.030.45 ± 0.02-
OMsα-terpineol11890.36 ± 0.060.74 ± 0.010.97 ± 0.050.30 ± 0.02
Aldehydedecanal1202--0.89 ± 0.10-
OMscarveol1217-0.24 ± 0.050.87 ± 0.03-
OMscitronellol12261.13 ± 0.041.1 ± 0.081.84 ± 0.070.20 ± 0.04
OMscarvone1243-0.14 ± 0.030.96 ± 0.08-
OMsα-terpinyl acetate1349-0.19 ± 0.020.34 ± 0.050.10 ± 0.02
OMsneryl acetate1362-0.12 ± 0.000.2 ± 0.01-
SHsα-copaene1377--0.15 ± 0.03-
OMsgeranyl acetate13810.67 ± 0.050.61 ± 0.041.25 ± 0.0 20.44 ±0.03
SHsβ-caryophyllene14192.61 ± 0.521.37 ± 0.161.84 ± 0.191.45 ± 0.11
SHsα-humulene1455-0.2 ± 0.07-0.19 ± 0.05
SHstrans-β-farnesene14570.79 ± 0.040.31 ± 0.021.2 ± 0.050.66 ± 0.06
SHssesquisabinene1458---0.17 ± 0.01
SHsgermacrene D1485--0.12 ± 0.02-
SHsvalencene1496-0.12 ± 0.01--
SHsbicyclo-germacrene15000.61 ± 0.070.33 ± 0.080.19 ± 0.050.59 ± 0.05
SHsα-farnesene15060.4 ± 0.010.21 ± 0.030.37 ± 0.03 0.34 ± 0.04
SHssesquiphellandrene-β1522---0.15 ± 0.00
SHsδ-cadinene1523-0.2 ± 0.01-0.10 ± 0.02
OSselemol1550-0.21 ± 0.030.18 ± 0.010.09 ± 0.02
OSsnerolidol1563-0.35 ± 0.050.56 ± 0.020.38 ± 0.04
OSsspathulenol1578-0.23 ± 0.06--
OSscaryophyllene oxide1583-0.32 ± 0.012.55 ± 0.110.07 ± 0.06
OSstrans-sesquisabinene hydrate1579-0.18 ± 0.02-0.18 ± 0.03
OSsα-cadinol1640-0.25 ± 0.01-0.12 ± 0.00
OSsT-muurolol1646-0.15 ± 0.020.19 ± 0.03-
OSsβ-sinensal17008.51 ± 0.995.82 ± 0.635.87 ± 0.877.82 ± 0.36
OSsα-sinensal17577.49 ± 0.040.21 ± 0.031.79 ± 0.090.20 ± 0.06
Total95.0894.8793.8793.19
-: not detected. MHs: monoterpene hydrocarbons, OMs: oxygenated monoterpenes, SHs: sesquiterpene hydrocarbons, OSs: oxygenated sesquiterpenes.
Table 5. Chemical groups and relative concentrations (area %) of the studied EOs from the leaves of clementine mandarin var. SRA 63 per rootstock combination.
Table 5. Chemical groups and relative concentrations (area %) of the studied EOs from the leaves of clementine mandarin var. SRA 63 per rootstock combination.
Chemical GroupsRelative Concentration (Area %)
S-R1S-R2S-R3 S-R4
MHs53.9956.1545.865.94
OMs20.682832.0214.74
SHs4.412.743.873.65
OSs16.07.7211.148.86
Aldehydes--0.89-
-: not detected.
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Ziogas, V.; Panou, E.; Graikou, K.; Ganos, C.; Ntamposi, E.; Chinou, I. Revealing the Influence of Rootstock Choice on Clementine Mandarin Leaves and Peel Volatile Profile. Horticulturae 2025, 11, 523. https://doi.org/10.3390/horticulturae11050523

AMA Style

Ziogas V, Panou E, Graikou K, Ganos C, Ntamposi E, Chinou I. Revealing the Influence of Rootstock Choice on Clementine Mandarin Leaves and Peel Volatile Profile. Horticulturae. 2025; 11(5):523. https://doi.org/10.3390/horticulturae11050523

Chicago/Turabian Style

Ziogas, Vasileios, Evgenia Panou, Konstantia Graikou, Christos Ganos, Evgenia Ntamposi, and Ioanna Chinou. 2025. "Revealing the Influence of Rootstock Choice on Clementine Mandarin Leaves and Peel Volatile Profile" Horticulturae 11, no. 5: 523. https://doi.org/10.3390/horticulturae11050523

APA Style

Ziogas, V., Panou, E., Graikou, K., Ganos, C., Ntamposi, E., & Chinou, I. (2025). Revealing the Influence of Rootstock Choice on Clementine Mandarin Leaves and Peel Volatile Profile. Horticulturae, 11(5), 523. https://doi.org/10.3390/horticulturae11050523

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