Caryologia. International Journal of Cytology, Cytosystematics and Cytogenetics 73(4): 85-98, 2020 Firenze University Press www.fupress.com/caryologia ISSN 0008-7114 (print) | ISSN 2165-5391 (online) | DOI: 10.13128/caryologia-1011 Caryologia International Journal of Cytology, Cytosystematics and Cytogenetics Citation: A. Giovino, A. Marchese, G. Domina (2020) Morphological and genetic variation of Chamaerops humilis (Are- caceae) in relation to the altitude. Caryologia 73(4): 85-98. doi: 10.13128/ caryologia-1011 Received: July 06, 2020 Accepted: September 24, 2020 Published: May 19, 2021 Copyright: © 2020 A. Giovino, A. Mar- chese, G. Domina. This is an open access, peer-reviewed article pub- lished by Firenze University Press (http://www.fupress.com/caryologia) and distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distri- bution, and reproduction in any medi- um, provided the original author and source are credited. Data Availability Statement: All rel- evant data are within the paper and its Supporting Information files. Competing Interests: The Author(s) declare(s) no conflict of interest. ORCID AG: 0000-0001-5501-0204 AM: 0000-0002-6816-6184 GD: 0000-0003-4184-398X Morphological and genetic variation of Chamaerops humilis (Arecaceae) in relation to the altitude Antonio Giovino1, Annalisa Marchese2,*, Gianniantonio Domina2 1 Council for Agricultural Research and Economics (CREA) – Research Centre for Plant Protection and Certification (CREA-DC), S.S. 113 Km 245,5, 90011, Bagheria (PA), Italy 2 Department of Agricultural, Food and Forest Sciences, University of Palermo, Viale delle Scienze, 11 bldg. 4, I-90128, Palermo, Italy *Corresponding author. E-mail: annalisa.marchese@unipa.it Abstract. The Mediterranean dwarf palm (Chamaerops humilis L.) is native to West- ern and Central Mediterranean. Since classical times this species has been cultivated and several varieties have been described on material of unknown origins. In this study, plants grown from seeds collected in the wild from seven populations spread along the Mediterranean basin were cultivated under the same environmental condi- tions, investigated morphologically and genetically by screening the polymorphism of ten SSR loci. Two groups are clearly separated, the populations growing at low altitudes and those living above a thousand meters of altitude. Due to morphologi- cal, geographic and environmental isolation, here it is proposed to discriminate the populations growing at high altitude on the Moroccan High Atlas and Anti-Atlas as a distinct subspecies. Keywords: European fan palm, dwarf fan palm, morphology, diversity, SSR markers, Morocco. INTRODUCTION The Mediterranean dwarf palm, Chamaerops humilis L. (Arecaceae) is one of the best known and typical species of the Mediterranean basin. This is due to its wide distribution and to its numerous uses since the dawn of civilization. C. humilis has been studied in relation to morphological and genetic diversity (Giovino et al. 2014, Giovino et al. 2015a, Guzmán et al. 2017), seed lipids composition (Giovino et al. 2015b), ethnobotany (Okka- cha et al. 2013). This species naturally occurs in Western and Central Mediterranean. It is widespread in the Iberian Peninsula, Morocco, Algeria, South France, Sar- dinia, Tunisia, Sicily and Peninsular Italy (Euro+Med 2006, Castroviejo and Galan 2007, Pignatti 2017). The eastern distribution limit of this species lies in Calabria, Italy. Linnaeus (1753) reported C. humilis as common in Spain. 86 Antonio Giovino, Annalisa Marchese, Gianniantonio Domina The original material used for lectotypification of this name is presumptively collected in Europe (Moore and Dransfield 1979). To date, the dwarf palm is considered a species threatened by human activities and environmental and climatic changes and for this reason deserves a special attention in conservation management strategies (Blach‐ Overgaard et al. 2010; Giovino et al. 2016). Chamaerops humilis is extremely variable in height, leaf colour, presence of thorns, size and shape of fruits (Beccari 1921, Zagolin 1921, Maire 1957). This large morphological variation is at the basis of the descrip- tion of numerous varieties. Despite the Kew Checklist of Palms (Govaerts and Dransfield 2005) reports more than 20 intra-specific epithets among varieties and sub-vari- eties, Giovino et al. (2014) reports that many morpho- logical traits appear to be related to environmental con- ditions. This scenario is complicated by the fact that a large part of known varieties has been described on cul- tivated plants of unknown origin. Whilst a great num- ber of names are used in the horticultural field, only two varieties are widely accepted in floras: C. humilis L. var. humilis and C. humilis var. argentea André (= C. humi- lis var. cerifera Becc.). They are mainly distinguished by leaves color: C. humilis L. var. humilis, has green leaves and C. humilis var. cerifera Becc. has grey and waxy leaves (Maire 1957). The aim of this contribution is to investigate the taxonomic value of C. humilis var. argentea André and to clarify if the morphological variability observed in high altitude populations studied in High Atlas and Anti Atlas in Morocco is merely due to environmental factors or if it is of genotypic nature and transmitted to prog- enies. MATERIALS AND METHODS A preliminary assessment of the morphological vari- ability of C. humilis in all the countries where it natural- ly occurs was performed. We were not able to find any wild individual in the Maltese archipelago, where this species was recorded by Haslam et al. (1977). After this preliminary evaluation, seven representative populations were chosen for this study. In order to exclude variability due to the environ- ment, plants grown from seeds collected in nature were studied ex-situ under the same environmental condi- tions in a collection field at the CREA-DC Research Center - Bagheria (N Sicily). These seeds were col- lected from three populations in Morocco (Terketen, BeniMellal, and Touama) (Figure 1), one population in Spain (Valencia), one in Algeria (Sidi Belattar near Mostaganem), one in Tunisia (Cap Serrat), and one in Sardinia, Italy (Porto Tangone) (Table 1). Seed collec- tions were done on at least six individuals occurring in the central part of wild populations. In December 2013, seeds were treated with either sulphuric acid, water or mechanical scarification as described in Giovino et al. (2015b). After, seeds were germinated on humid sand for about 100 days (MGT) in a cold greenhouse with temperatures between 12 °C and 16 °C at rela- tive humidity of 90%. After germination plants were transplanted on pots of 1.6 ℓ containing a mixture of sand (70%), red soil (25%) and commercial garden soil (5%). Pots were maintained on open air from April to November and irrigated with 1 dripper 2 ℓ/h providing 2 min irrigation per day for three days a week. After two years plant were transplanted in 7 ℓ pots contain- ing the same substratum. Figure 1. Elevation of the collecting localities in Morocco. MAR: Terketen; MAR1: Beni Mellal; MAR2: Touama. 87Morphological and genetic variation of Chamaerops humilis (Arecaceae) in relation to the altitude For morphological analysis, the selection of char- acters was done on the basis of Rhouma (1994, 2005), Hammadi et al. (2009), Rizk and El Sharabasy (2007). Measures were done in spring 2018 with a digital caliper. For each character three measures were per- formed and their arithmetic average registered. Per each population 31 individuals were measured. On the whole 12 quantitative characters were measured; nine continu- ous: Height of the stem (cm), Height of the plant (cm), Crown diameter (cm), Stem diameter (mm), Petiole length (cm), Petiole width (cm), Leaf length (cm), Leaf width (cm), Leaf thickness (mm) and three discrete ones: No. of leaf segments, No. thorns on the petiole, and wax coverage density. This latter was estimated on percentage of coverage on the upper surface of the leaf. The measures used for statistics are presented in the Supplemental data (File 1). According to the meth- odology adopted in Giovino et al. (2015c), Domina et al. (2017a, 2017b), and Domina (2018) these characters were subjected to a Principal Component Analysis, with the individuals a priori assigned to the eight pop- ulations (Figure 2). Each character was also subjected to univariate analysis (analysis of variance or Kruskal– Wallis test with corrections for multiple comparisons, Pearson correlation coefficients, Tukey’s HSD, honestly significant difference, test and Bonferroni, respectively), Table 1. Sampled populations, environmental characteristics and seeds collection data. Code Locality Latitude Longitude Altitude m a.s.l. Habitat Bioclimate Date Collector MAR Terketen, Morocco 31°27’44.47”N 7°24’23.39”W 1420 Mediterranean steppe Humid 21.10.2012 A. Giovino MAR1 Beni Mellal, Morocco 32°25’54.78”N 6°30’41.76”W 430 Mediterranean maquis Semiarid 21.10.2012 A. Giovino MAR2 Touama, Morocco 31°31’46.14”N 7°28’59.82”W 990 Mediterranean steppe Humid 21.10.2012 A. Giovino SPA Valencia, Spain 40°16’15.12”N 0°17’12.04”E 130 Mediterranean maquis Semiarid 15.10.2012 P. Ferrer Galego ALG Sidi Belattar, Algeria 36°01’43.07”N 0°09’03.03”E 200 Mediterranean maquis Semiarid 5.9.2013 A. Mostari TUN Cap Serrat, Tunisia 37°11’ 55.8”N 09°15’45.9”E 20 Mediterranean maquis Humid 5.9.2013 R. El Mokni SAR Porto Tangone, Italy 40°28’19.23”N 8°22’52.98”E 50 Mediterranean maquis Semiarid 25.06.2013 A. Giovino Figure 2. Principal components analysis based on the 12 considered morphological characters, with 7 a priori defined groups based on the geographical distribution of the sampled populations. PC1 Eigenvalue 645.724, % variance 76.48, PC2 Eigenvalue 132.387, % variance 15.68. MAR: Terketen, Morocco; MAR1: Beni Mellal, Morocco; MAR2: Touama, Morocco; SPA: Valencia, Spain; ALG: Sidi Belattar, Algeria; TUN: Cap Serrat, Tunisia; SAR: Porto Tangone, Sardinia, Italy. 88 Antonio Giovino, Annalisa Marchese, Gianniantonio Domina using PAST version 4.03 (Hammer et al. 2001; Hammer 2020). Pearson correlation coefficients (r) among the 12 characters measured are presented in the Supplemen- tal data (File 2). A discriminant analysis for the seven a priori recognized groups was performed. The scatter plot of specimens along the first two canonical axes is shown (Figure 3). The range of each continuous numer- ical character is represented using box-and-whisker plots (Figure 4). For molecular analysis a total of 35 genotypes were used for the characterization: 5 from Terketen (Moroc- co); 5 from Beni Mellal (Morocco); 4 from Touama (Morocco); 6 from Valencia (Spain); 6 from Mostaganem (Algeria); 3 from Cap Serrat (Tunisia), and 6 from Porto Tangone (Sardinia, Italy). Genomic DNA was extracted from 40 mg of dried leaf sample using Doyle & Doyle (1987) protocol. A set of 10 microsatellite markers was employed, including 6 microsatellites showing trinucleotide repeats (Arranz et al. 2013) and 4 showing dinucleotide repeats recently isolated in fan palm by Giovino et al. (submitted 2020) following PCR conditions and thermal cycles reported in Giovino et al. (2014) and Giovino et al. (submitted 2020) (Table 2). PCR products were analyzed using an ABI 3130 Genetic Analyzer (Applied Biosystems) and allele sizes were established using GENEMAPPER, version 4.0 software (Applied Biosystems). Basic genetic parameters including the number of alleles per locus (Na), observed (Ho) and expected het- erozygosity (He), the total number of null alleles (Fnull), the polymorphic information content (PIC) value and the deviation from the Hardy-Weinberg equilibrium (HWE), inferred by sequential Bonferroni correction, in the 36 selected genotypes, were calculated using CER- VUS 3.0 software (Marshall et al. 1998; Kalinowski et al. 2007). A Neighbor-Net graph was constructed based on calculations of Reynold’s genetic distances with SPLIT- STREE (Huson and Bryant 2006) in order to study the genetic diversity and relationships between palm geno- types (Figure 5). RESULTS Morphological characterisation Single morphological characters (Figure 4) show continuous variation and do not distinct population groupings. The population from Cap Serrat shows the largest intra-population variation. Only the leaf length distinguishes, in part, some populations from the others. Univariate analysis shows that this character discrimi- nates Moroccan populations from the others. Figure 3. Discriminant analysis based on the 12 considered morphological characters, with 7 a priori defined groups based on the geo- graphical distribution of the sampled populations. Axis 1: Eigenvalue 22.424, % variance 74.11; Axis 2: Eigenvalue 5.635, % variance 18.62. MAR: Terketen, Morocco; MAR1: Beni Mellal, Morocco; MAR2: Touama, Morocco; SPA: Valencia, Spain; ALG: Sidi Belattar, Algeria; TUN: Cap Serrat, Tunisia; SAR: Porto Tangone, Sardinia, Italy. 89Morphological and genetic variation of Chamaerops humilis (Arecaceae) in relation to the altitude The principal components analysis (Figure 2) and the discriminant analysis (Figure 3) show three well dis- tinct groups across the populations studied. The cases correctly classified by discriminant analysis according to the groups assigned a priori were 91.4%. Molecular characterisation A total of 71 SSR alleles were identified across the 10 loci (Table 2) in 35 dwarf palm genotypes and all indi- viduals were differentiated. Locus37 showed the highest Figure 4. Box-plots of the 9 continuous morphological characters considered (A: height of the Stem (cm); B: Height of the Plant (cm); C: Crown diameter (cm); D: Stem diameter (mm); E: Petiole length (cm); F: Petiole width (cm); G: Leaf length (cm); H: Leaf width (cm); I: Leaf thickness (mm). For each sample, the 25–75% quartiles are drawn using a box. The median is shown with a horizontal line inside the box. The whiskers are drawn from the top of the box up to the largest data point less than 1.5 times the box height from the box, and simi- larly below the box. Values outside the inner fences are shown as circles, values further than 3 times the box height from the box are shown as stars. MAR (fuchsia): Terketen, Morocco; MAR1 (yellow): Beni Mellal, Morocco; MAR2 (grey): Touama, Morocco; ALG (light blue): Sidi Belattar, Algeria; SPA (orange): Valencia, Spain; TUN (blue): Cap Serrat, Tunisia; SAR (red): Porto Tangone, Sardinia, Italy. 90 Antonio Giovino, Annalisa Marchese, Gianniantonio Domina number of observed alleles per locus (16) while locus16 and locus23 the lowest (3); the average number of alleles per locus was 7.1. Seven SSR markers were found highly informative (PIC > 0.5) and three reasonably informative (0.25 < PIC < 0.5); PIC average was 0.62. For eight SSR loci the expected heterozygosity (He) was higher than the observed heterozygosity, except for locus35 and locus44, which deviated from Hardy Wein- berg equilibrium. Mean He resulted 0.67 and the mean Ho was 0.54. Interestingly, a rare allele of 97 bp at the locus37 was found restricted to two genotypes from Terketen (MAR1 and MAR8). Neighbor-Net method cluster analysis (Fig- ure 5) showed that the Moroccan genotypes separated from all genotypes of the other geographical areas. Over- all genotypes from Beni Mellal presented an intermediate genetic proximity with other populations. Two genotypes MAR6 and MAR7 from Terketen showed closer relation- ship with Touama genotypes. Algerian, Sardinian, Span- ish, and Tunisian genotypes shared closer relationships and genotypes from Sardinia grouped together. DISCUSSION The large intrapopulational morphological variation observed testifies a large genetic variability among the studied populations. This variation was proven by the molecular analysis. A rich assortment of SSR alleles was found indicat- ing a greater genetic diversity than that previously iden- tified on 705 Sicilian dwarf palm genotypes using 28 SSR markers (Giovino et al. 2014). This information is useful for acquiring new knowledge on the species and for planning a more extensive work on the whole area of distribution of this species in order to acquire a more detailed knowledge to preserve Chamaerops humilis genetic diversity in the future. As concern the presence of a rare allele restricted to some genotypes of the Terketen population, it is possi- ble to speculate that this allele may reflect an adaptation to particular environment conditions or stresses. It has been shown in many species that SSR diversity is adap- tive, influenced by natural and anthropic selection and correlated with ecological-edaphic and genetic factors (Marchese et al. 2010, Marchese et al. 2017). Natural selec- tion plays an essential role in controlling the length of a repeat (Li et al. 2000). King and Soller (1999) proposed that changes in length of SSRs functionally integrated into the genome can influence plant adaptive fitness. However, further molecular studies are needed, including a greater number of genotypes representative of all dwarf palm populations, to confirm the uniqueness of this allele. In the Neighbor-Net cluster analysis the Moroc- can genotypes grouped together and appeared separated from Algerian, Sardinian, Spanish, and Tunisian geno- types which seemed to share closer relationships, among this latter group the Sardinian genotypes grouped joint- ly. In general, the Neighbor-Net cluster analysis was in agreement with the discriminant analysis. According to the observed variability, it seems opportune to distinguish the populations of high alti- tude of Atlas and Anti-Atlas as a distinct subspecies. A careful bibliographic research has allowed us to ascertain that the name Chamaerops humilis var. Figure. 5. Split tree of 35 Chamaerops humilis genotypes of five putative populations based on Nei and Li’s genetic distance. MAR: Terketen, Morocco; MAR1: Beni Mellal, Morocco; MAR2: Touama, Morocco; SPA: Valencia, Spain; ALG: Sidi Belattar, Algeria; TUN: Cap Serrat, Tunisia; SAR: Porto Tangone, Sardinia, Italy. Table 2. SSR locus name, number of alleles (No), observed (Ho) and expected heterozygosities(He), polymorphic information con- tent (PIC) of 10 microsatellite loci in a sample of 35 accessions of Chamaerops humilis. Locus name Allele No H exp Ho PIC locus19 6 0,64 0,36 0,55 locus25 12 0,84 0,44 0,8 locus27 9 0,85 0,47 0,82 locus15 5 0,63 0,58 0,57 locus16 3 0,5 0,36 0,43 locus23 3 0,26 0,14 0,25 Locus35 6 0,65 0,83 0,58 Locus37 16 0,9 0,72 0,88 Locus44 4 0,58 0,97 0,49 Locus48 7 0,83 0,55 0,79 Mean 7,1 0,668 0,542 0,62 91Morphological and genetic variation of Chamaerops humilis (Arecaceae) in relation to the altitude argentea André Rev. Hort. 57: 231 (1885) quoted by the large part of repertoires and floras (e.g. Maire 1957, Fen- nane 2014) has never been published either in that place or, as far as we have been able to verify, in other sources. So, the first validly published name that can refer to this entity is C. humilis var. cerifera Becc. described on mate- rial cultivated in Naples of dubious origin. The study of original material housed in FI, where the Herbarium by Beccari is housed (Cuccuini and Nepi 2006) was not suf- ficient to dispel the doubts because the single specimen found (Beccari n. 384) consists only of badly preserved fruits. In any case the only known populations in nature with grey leaves, due to the high concentration of wax- es on their surface, are found exclusively in Morocco at high altitudes, thus the taxon described by Beccari, by reasonable assumption, refers to these populations. The following new combination is proposed: Chamaerops humilis subsp. cerifera (Becc.) Giovino & Domina subsp. nov. (≡C. humilis var. cerifera Becc. in Webbia 5(1): 65 1921). Type: Lectotype (here designated): Beccari n. 384, Chamaerops humilis L. v. cerifera Becc.; Italia, Napoli, n. 1919, Ruffo, ex Ruffo principe di S. Antimo (FI). This subspecies differs from C. humilis subsp. humi- lis by its leaves glaucous-silvery, dull, covered with per- sistent scaly hairs. The individuals in form of compact tufts with short stems and smaller leaves blades com- monly found in high altitude populations in High Atlas and Anti Atlas are due to the effect of environmental and anthropozoogenic degradation. CONCLUSION The obtained results agree with those by García- Castaño et al. (2014): C. humilis has a large morpho- logical and genetic variation throughout its distribution range. The southern populations from Morocco are iso- lated from the resting ones and in particular high-alti- tude populations are well distinct from the morphologi- cal and genetic points of view due to a speciation under- way moved by ecological and spatial separation to which they are subjected. Thus, it is here proposed to discrimi- nate these populations within a separated subspecies. These results encourage about the possibility of cul- tivating Chamaerops humilis subsp. cerifera also in envi- ronments with lower temperatures than the Mediter- ranean coasts where C. humilis subsp. humilis has been confined so far. Such cultivations would have primary interest as ornamental but the possibility of extraction of medicinal principles is not excluded. 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Ethnobotanical approaches and phytochemical analy- sis of Chamaerops humilis L. (Arecaceae) in the area of tlemcen (western Algeria). Res J Pharm Biol Chem Sci 4(2):910–918 Pignatti S. 2017. Chamaerops L. Pp. 381-382 in: Flora d’Italia, 1, 2° ed. Edagricole, Milano. Zagolin A. 1921. Ricerche sul polimorfismo del frutto della Chamaerops humilis L. N Giorn Bot Ital., n.s., 28:36–66. 93Morphological and genetic variation of Chamaerops humilis (Arecaceae) in relation to the altitude Supplemental Data file 1. Mean of the measures on morphological characters used for statistical analysis. Code Population H ei gh t o f t he st em ( cm ) H ei gh t o f t he pl an t ( cm ) C ro w n di am et er ( cm ) St em d ia m et er (m m ) Pe tio le w id th (c m ) Pe tio le w id th (c m ) Le af le ng th (c m ) Le af w id th (c m ) Le af th ic kn es s (m m ) N o. o f l ea f se gm en ts N o. th or ns o n th e pe tio le W ax c ov er ag e de ns ity % MAR_1 Terketen, Morocco 7,5 17 27 34,5 3,9 3,2 8,7 11,8 1 9 0 95 MAR_2 Terketen, Morocco 8 20 22 29,9 3,1 3,5 9,7 13,7 0,8 8 5 95 MAR_3 Terketen, Morocco 6 20 28 28,6 0,9 4,1 11,5 14 0,8 9 8 95 MAR_4 Terketen, Morocco 4,5 15,5 19 34,5 0,8 3,3 9,5 11 0,7 10 1 95 MAR_5 Terketen, Morocco 9 19 24 47,5 3,3 2,7 8,8 10,6 0,5 9 2 95 MAR_6 Terketen, Morocco 6 20 21 29,4 4,2 4,2 12,7 15,5 1,1 9 0 95 MAR_7 Terketen, Morocco 6 26,5 31 23,8 3,7 6 13,6 17,7 0,7 11 4 95 MAR_8 Terketen, Morocco 8 20 23 31,5 3 4,7 10,3 13 0,9 11 0 95 MAR_9 Terketen, Morocco 11,5 29 36 34,5 3,4 6 11,3 15 0,8 11 6 95 MAR_10 Terketen, Morocco 9,5 22 24 20,5 3,2 3,7 9,4 10,5 0,5 8 9 95 MAR_11 Terketen, Morocco 7 18,5 26 34,9 3,3 5 9 11,5 1,2 9 10 95 MAR_12 Terketen, Morocco 7,5 23 30,5 34,9 3,9 4,5 10,2 13,2 0,9 11 7 95 MAR_13 Terketen, Morocco 8 21,5 28 27,3 2,7 3,2 9 10,5 0,4 9 4 95 MAR_14 Terketen, Morocco 6 16 20 31,7 3,2 2,7 5,2 10,7 0,7 9 4 95 MAR_15 Terketen, Morocco 8 20 21 29,5 2,9 2,8 11,4 13,7 0,8 10 5 95 MAR_16 Terketen, Morocco 7,5 23 24 26,2 3,1 2,7 10 10,2 0,4 9 11 95 MAR_17 Terketen, Morocco 8 22,5 26,5 34,8 2,5 4,4 10,7 10,1 0,5 9 1 95 MAR_18 Terketen, Morocco 9 21 29,2 34,2 3,1 4,3 9,7 8,5 0,7 8 3 95 MAR_19 Terketen, Morocco 4 12 16 33,5 2,8 2 6,5 9,5 0,5 7 15 95 MAR_20 Terketen, Morocco 8 21 32 34,4 3,9 4,5 9,8 12,2 1 10 5 95 MAR_21 Terketen, Morocco 6,5 27,5 32 33,4 3 9,5 14,3 19,2 0,5 9 9 95 MAR_22 Terketen, Morocco 8 21,5 30 38,5 3,1 4,2 9,5 10,2 0,4 9 13 95 MAR_23 Terketen, Morocco 10 25 31 28,2 3 5,5 12,3 14,5 0,5 11 12 95 MAR_24 Terketen, Morocco 6 2,6 30,5 35,4 3 4,5 10,5 13,2 0,5 10 12 95 MAR_25 Terketen, Morocco 10 23,5 35,5 44,8 2,6 4,7 10 14,8 0,5 10 6 95 MAR_26 Terketen, Morocco 4 21 23 27,8 3 3,8 9,7 13,2 0,6 9 1 95 MAR_27 Terketen, Morocco 6 20 29,5 30,1 3,5 4,8 10,2 13,8 0,6 9 11 95 MAR_28 Terketen, Morocco 7 21 29 24,1 3,1 3,7 9,5 14 0,6 9 7 95 MAR_29 Terketen, Morocco 4 20 30 24,4 2,7 5 12,3 16,8 0,6 8 4 95 MAR_30 Terketen, Morocco 9 22 28,5 34,2 3,4 5,3 12 15,2 0,8 11 7 95 MAR_31 Terketen, Morocco 6 24 34,5 29,8 3,3 6,3 12,3 14,2 0,8 8 11 95 MAR1_1 Beni Mellal, Morocco 4 20 30 14,3 3,8 2 16,8 11 0,9 4 5 55 MAR1_2 Beni Mellal, Morocco 4 17 31 26,5 4,6 4 15 14 0,8 10 6 55 MAR1_3 Beni Mellal, Morocco 3,5 17,5 29 4,3 3,7 2,3 16,7 12,7 0,7 5 3 55 MAR1_4 Beni Mellal, Morocco 4 15 20 16,4 4 2,2 12 12,3 1 7 5 65 MAR1_5 Beni Mellal, Morocco 3 15,5 17 16 3,3 2,7 10,3 9 0,6 6 5 65 MAR1_6 Beni Mellal, Morocco 4 14 17 20 3,5 2 10,2 9,3 1,3 7 3 65 MAR1_7 Beni Mellal, Morocco 4 14 17 20 2,5 1,5 9 6 0,6 6 0 65 MAR1_8 Beni Mellal, Morocco 3,5 21,5 41 20 3,4 5,3 16,3 12 0,7 6 6 55 MAR1_9 Beni Mellal, Morocco 4 14,5 23 24 1,2 3,2 11,7 8 0,8 5 0 55 MAR1_10 Beni Mellal, Morocco 5 18,5 25 18,3 3,5 3,2 15,2 12,3 0,8 11 5 65 MAR1_11 Beni Mellal, Morocco 2 12,5 21 17 3,3 2,8 12,2 8 0,7 7 3 75 MAR1_12 Beni Mellal, Morocco 3 18 18 23 3,9 2,2 13,7 9 0,9 6 3 65 MAR1_13 Beni Mellal, Morocco 3 19 25 18 3,8 3 14,5 9 0,7 6 6 75 MAR1_14 Beni Mellal, Morocco 4 16,5 24 19 3,5 2,9 12,6 9 0,9 6 3 55 MAR1_15 Beni Mellal, Morocco 4 17,5 23 17,5 3,3 2,6 11 9,3 0,9 5 3 55 94 Antonio Giovino, Annalisa Marchese, Gianniantonio Domina Code Population H ei gh t o f t he st em ( cm ) H ei gh t o f t he pl an t ( cm ) C ro w n di am et er ( cm ) St em d ia m et er (m m ) Pe tio le w id th (c m ) Pe tio le w id th (c m ) Le af le ng th (c m ) Le af w id th (c m ) Le af th ic kn es s (m m ) N o. o f l ea f se gm en ts N o. th or ns o n th e pe tio le W ax c ov er ag e de ns ity % MAR1_16 Beni Mellal, Morocco 3 18 22 23 3,6 2,9 13 9,2 0,7 7 5 65 MAR1_17 Beni Mellal, Morocco 3 16,5 20 17 3,8 3,2 12,8 9,2 0,7 6 3 65 MAR1_18 Beni Mellal, Morocco 3,5 16 24 23 3,7 2,9 12,5 8,7 0,9 6 3 76 MAR1_19 Beni Mellal, Morocco 3 17 23 23 2,9 3,2 16 12,5 0,7 6 5 65 MAR1_20 Beni Mellal, Morocco 4 15 26 21 3,6 4 16 13,5 0,9 6 3 55 MAR1_21 Beni Mellal, Morocco 4 15,5 25 18 3,5 3,6 17 13,2 0,6 7 3 65 MAR1_22 Beni Mellal, Morocco 3,5 16,5 19 23 3,2 2,8 12,7 8,3 0,7 6 5 76 MAR1_23 Beni Mellal, Morocco 3 18 25 18,5 3 3,1 15,1 12 0,9 6 3 65 MAR1_24 Beni Mellal, Morocco 5 19 24 19 2,9 2,7 12 9,8 0,9 6 5 65 MAR1_25 Beni Mellal, Morocco 4 18 19 19 3,3 3,5 16,6 13,2 0,6 7 0 55 MAR1_26 Beni Mellal, Morocco 3,5 17,5 23 18 3,5 3,4 17,2 13 0,7 6 5 65 MAR1_27 Beni Mellal, Morocco 4 18 24 18,5 3,6 3,3 12 8,2 0,9 5 3 65 MAR1_28 Beni Mellal, Morocco 3,5 18,5 22 21 3 4 15,5 13,8 0,7 6 5 75 MAR1_29 Beni Mellal, Morocco 4 17 20 22 2,9 2,8 14 12,6 0,9 6 3 55 MAR1_30 Beni Mellal, Morocco 3 18 24 23 3,4 3 13,7 8,9 0,8 7 3 65 MAR1_31 Beni Mellal, Morocco 4 17 24 26 3,6 2,7 12 10,3 1,1 7 3 55 MAR2_1 Touama, Morocco 3 17,5 25 20 3,4 3,5 14,3 10,7 0,4 7 0 55 MAR2_2 Touama, Morocco 3 13 15 19 3,1 2,2 10,5 8 0,4 7 0 65 MAR2_3 Touama, Morocco 3 16 16 22 2,8 2,3 12,7 10,7 0,7 6 0 75 MAR2_4 Touama, Morocco 3 15 18 16 3,6 2,7 11,7 12,7 0,7 9 0 75 MAR2_5 Touama, Morocco 4 14 20 12 3,6 2,7 10,3 10 0,9 6 0 75 MAR2_6 Touama, Morocco 3 17 23 12 2,6 5,3 13,7 10 0,7 7 0 65 MAR2_7 Touama, Morocco 5 14 10 25 2,3 3 8,7 6 1,4 5 0 55 MAR2_8 Touama, Morocco 4 16 22 20 2,6 3 12,6 10,8 0,6 6 0 55 MAR2_9 Touama, Morocco 4 17 23 22 2,7 3,1 13,5 10 0,7 5 0 65 MAR2_10 Touama, Morocco 3 17 18 18 2,6 2,8 10,5 9,6 0,9 7 0 55 MAR2_11 Touama, Morocco 3 18 22 20 3 2,9 11,9 12,5 0,6 6 0 65 MAR2_12 Touama, Morocco 5 16 23 22 2,6 4 12,7 10,7 0,7 5 0 75 MAR2_13 Touama, Morocco 4 16 18 20 2,8 2,8 12 10 1 7 0 55 MAR2_14 Touama, Morocco 3 17 20 18 2,8 2,7 10,7 9,8 0,6 5 0 65 MAR2_15 Touama, Morocco 3 17 23 22 3 3 13,5 9,5 0,7 6 0 55 MAR2_16 Touama, Morocco 5 18 20 18 4 2,8 11,9 9 0,9 7 0 75 MAR2_17 Touama, Morocco 5 17 18 20 2,8 3 12,7 10,5 1 6 0 65 MAR2_18 Touama, Morocco 4 16 22 25 2,8 3 10,8 9,8 0,6 5 0 75 MAR2_19 Touama, Morocco 4 17,5 23 23 3,1 2,7 12,2 9,6 0,7 6 0 55 MAR2_20 Touama, Morocco 3 18 22 22 3 2,6 13,1 8,7 1 7 0 65 MAR2_21 Touama, Morocco 3 17 20 19 2,8 2,9 12,7 10,7 0,9 6 0 75 MAR2_22 Touama, Morocco 3 18 20 21 4 3,1 12,2 10,5 0,6 6 0 55 MAR2_23 Touama, Morocco 4 17,5 22 20 2,6 2,5 13,4 9 0,7 7 0 65 MAR2_24 Touama, Morocco 5 16 23 20 3 2,6 9,6 7 0,9 6 0 75 MAR2_25 Touama, Morocco 4 16 22 18 2,8 2,7 12,4 10,7 0,6 6 0 55 MAR2_26 Touama, Morocco 3 14 24 20 3,2 2,8 11,3 10,3 0,6 5 0 75 MAR2_27 Touama, Morocco 3 15 21 22 3,2 4,2 13,7 10 0,7 6 0 55 MAR2_28 Touama, Morocco 5 15,5 20 19 2,8 3,2 15 11,4 0,7 7 0 75 MAR2_29 Touama, Morocco 4 17,5 20 21 2,9 3,6 15,3 10,5 0,6 6 0 55 MAR2_30 Touama, Morocco 4 17 22 22 3 3,6 12,8 10,5 0,9 7 0 55 MAR2_31 Touama, Morocco 3 17 18 19 2,6 3 13 11,7 0,7 7 0 65 95Morphological and genetic variation of Chamaerops humilis (Arecaceae) in relation to the altitude Code Population H ei gh t o f t he st em ( cm ) H ei gh t o f t he pl an t ( cm ) C ro w n di am et er ( cm ) St em d ia m et er (m m ) Pe tio le w id th (c m ) Pe tio le w id th (c m ) Le af le ng th (c m ) Le af w id th (c m ) Le af th ic kn es s (m m ) N o. o f l ea f se gm en ts N o. th or ns o n th e pe tio le W ax c ov er ag e de ns ity % ALG1 Sidi Belattar, Algeria 7,5 29 31 19,8 3,6 7,3 21,3 18,3 0,7 8 8 25 ALG2 Sidi Belattar, Algeria 7 25,5 41 25,1 3,8 6,2 21,7 19,7 0,6 10 8 25 ALG3 Sidi Belattar, Algeria 7 23 27 19,8 3,9 5 15 16 0,9 7 8 25 ALG4 Sidi Belattar, Algeria 6,5 22,5 24,5 21 3,7 6 18,3 14,2 0,8 5 6 25 ALG5 Sidi Belattar, Algeria 6 26 32,5 24 3,3 7,2 21,5 15,2 0,6 6 6 25 ALG6 Sidi Belattar, Algeria 2,5 25,5 35 14,3 3,8 6,7 24,2 8,3 0,4 4 7 25 ALG7 Sidi Belattar, Algeria 3,5 21 29 12 3,9 5,2 20,7 12,2 0,8 6 7 25 ALG8 Sidi Belattar, Algeria 4 22 37 19,2 4,2 6,2 20,7 11,3 0,8 7 7 25 ALG9 Sidi Belattar, Algeria 4 18 31 12,3 3,8 2,2 16 7,3 0,9 4 2 30 ALG10 Sidi Belattar, Algeria 7 28 41 24,6 3,2 6 22 10,3 0,8 6 7 35 ALG11 Sidi Belattar, Algeria 5 18 27 13,8 3,4 4 14,5 8,7 0,5 7 6 35 ALG12 Sidi Belattar, Algeria 5 20 26 29,1 3,1 10 3,8 6,8 0,5 10 4 35 ALG13 Sidi Belattar, Algeria 7 18 28 21,7 3,7 5,2 19,2 5,3 0,8 6 5 45 ALG14 Sidi Belattar, Algeria 8 29,5 34 35,4 3,6 7,7 19,3 13,7 0,7 12 13 45 ALG15 Sidi Belattar, Algeria 3 22 38 19,5 3,9 4,8 8,7 8,3 0,9 7 8 45 ALG16 Sidi Belattar, Algeria 6 30 33 14,8 3,1 5,8 20,3 7,3 0,7 4 5 45 ALG17 Sidi Belattar, Algeria 5 23 30 23 3,2 4,7 15 10,7 0,6 7 1 45 ALG18 Sidi Belattar, Algeria 5 21 29 34,3 3,1 5,5 15,8 11,7 1,3 7 5 45 ALG19 Sidi Belattar, Algeria 7 16 26,5 26 4 3,8 12,7 7 0,6 9 4 45 ALG20 Sidi Belattar, Algeria 5,5 27,5 30 14,5 3,5 5,2 21 7,2 0,6 7 6 45 ALG21 Sidi Belattar, Algeria 4 20 30 25 3,9 4,5 16 9,8 0,8 7 2 45 ALG22 Sidi Belattar, Algeria 4,5 20 28 24,8 3,6 6 17,2 14,8 1 8 4 45 ALG23 Sidi Belattar, Algeria 5,5 28,5 33,5 17,3 3,5 6,2 22 12,3 1 5 6 45 ALG24 Sidi Belattar, Algeria 4 22 30 12,4 4 6,5 20 6 0,8 7 9 45 ALG25 Sidi Belattar, Algeria 5 28 28 15,7 3,7 6,2 18,2 9,7 0,9 6 5 45 ALG26 Sidi Belattar, Algeria 7 23 39 25,8 4,3 5,3 21,8 14,3 0,7 8 8 35 ALG27 Sidi Belattar, Algeria 4 21 24 31 4,4 3,3 14,5 8 1,2 6 4 35 ALG28 Sidi Belattar, Algeria 4 26 31 16,2 5,2 2,7 17 16 0,7 9 3 35 ALG29 Sidi Belattar, Algeria 6 20 25 20,5 4,1 3,7 11,8 11,7 1,1 10 3 35 ALG30 Sidi Belattar, Algeria 5 25 29 15,8 3,8 4,5 19,7 8 0,8 8 3 35 ALG31 Sidi Belattar, Algeria 6 21 36 20,3 3,6 5,7 17,2 12,8 0,5 6 7 35 SPA1 Valencia, Spain 6,5 24 27,5 23,6 4,1 5,2 16 16,2 1,6 9 7 35 SPA2 Valencia, Spain 4 28 29,5 15,3 3,7 7,2 23 24,5 0,9 6 11 35 SPA3 Valencia, Spain 3,5 30 34 13,1 3,5 5,7 29 19,3 1,2 6 7 35 SPA4 Valencia, Spain 3 21 24 16,9 4,3 3,3 16 18 2,8 6 5 35 SPA5 Valencia, Spain 6 24 32 18,8 4,4 4,3 19,5 15 1,8 4 7 35 SPA6 Valencia, Spain 5 20,5 24 18,4 3,1 6,7 19,2 18,2 2 7 8 35 SPA7 Valencia, Spain 2,5 20,5 24 13,5 4,1 3,5 14,7 12,8 0,9 5 5 35 SPA8 Valencia, Spain 4 27 27 14,2 4,4 4,8 23,7 9,7 1,9 4 4 30 SPA9 Valencia, Spain 6 29,5 25 29,3 3,8 4,7 19,2 15,8 1,3 5 7 25 SPA10 Valencia, Spain 3,5 27 30 19,3 3,4 7 19,7 16 2 6 9 25 SPA11 Valencia, Spain 4,5 26 29,3 18,5 3,8 7,8 22,2 15 1,5 7 11 25 SPA12 Valencia, Spain 4 24,5 30 23 3,8 7,5 20,7 16 1,3 7 10 25 SP13 Valencia, Spain 5,5 28,5 24 21,7 4,7 5,7 5,8 14 1,6 7 11 25 SPA14 Valencia, Spain 4 35 39 33,8 6,2 7,8 26 24 2,3 9 11 25 SPA15 Valencia, Spain 4 23 26 21,7 2,9 4,3 17 10 1,4 7 7 35 SPA16 Valencia, Spain 4 27,5 33 20,1 4,3 6,5 19 15,8 1,7 7 10 35 96 Antonio Giovino, Annalisa Marchese, Gianniantonio Domina Code Population H ei gh t o f t he st em ( cm ) H ei gh t o f t he pl an t ( cm ) C ro w n di am et er ( cm ) St em d ia m et er (m m ) Pe tio le w id th (c m ) Pe tio le w id th (c m ) Le af le ng th (c m ) Le af w id th (c m ) Le af th ic kn es s (m m ) N o. o f l ea f se gm en ts N o. th or ns o n th e pe tio le W ax c ov er ag e de ns ity % SPA17 Valencia, Spain 4,5 27 20,5 22,2 4,2 4,7 17,5 14,7 0,9 8 6 35 SPA18 Valencia, Spain 4 21 28,5 22,3 4,9 4,5 17,7 20,7 1,6 8 11 35 SPA19 Valencia, Spain 3,5 21,5 27 22,5 4,3 4,7 15,5 14,3 1,6 7 7 35 SPA20 Valencia, Spain 2,5 20,5 24 13,2 4,1 2,2 16 11,7 1,4 6 3 35 SPA21 Valencia, Spain 3,5 20 24,5 15,4 5,4 2,3 15,7 12 1,1 6 3 35 SPA22 Valencia, Spain 3,5 18 23 14,5 5,1 2,5 13,5 13 1,3 7 2 35 SPA23 Valencia, Spain 5 22,5 26 17,3 3,9 2,8 19,2 14,5 1,3 6 8 35 SPA24 Valencia, Spain 5 28 28 19,1 4,2 7 22,3 14,3 1,4 7 11 35 SPA25 Valencia, Spain 3 30 29,5 18 5,4 4,5 23,2 14,2 1,7 6 3 35 SPA26 Valencia, Spain 4 33 36 12,6 4,3 6,7 27,7 22,5 2,5 6 10 35 SPA27 Valencia, Spain 4 25,5 26 17 4,5 5,5 20 11,8 1,5 6 3 35 SPA28 Valencia, Spain 3 28 23 11 3,7 5,7 19,5 13,2 0,9 7 8 35 SPA29 Valencia, Spain 3,5 26,5 21 12,8 4,1 6 16,3 11,8 0,9 7 6 35 SPA30 Valencia, Spain 4 27 25,5 13,4 3,8 5,8 13,3 12,2 0,7 6 10 35 SPA31 Valencia, Spain 3 27,5 22 11,5 3,4 5,5 12,5 12,2 1 5 7 35 TUN1 Cap Serrat, Tunisia 3 31 33,5 20,3 4,2 8,3 27,3 23 0,8 7 8 25 TUN2 Cap Serrat, Tunisia 4 41 46 33,5 4,3 11,7 30 20 0,6 7 11 25 TUN3 Cap Serrat, Tunisia 2 24.5 22 17,7 3,6 2,3 16,3 11,8 1,2 4 0 25 TUN4 Cap Serrat, Tunisia 2 16 26 18,1 3,7 3 13 11,3 1,3 7 0 25 TUN5 Cap Serrat, Tunisia 2 18 28 20,6 4,7 3,3 16,3 16,3 0,8 10 5 25 TUN6 Cap Serrat, Tunisia 6 36,5 43 20,2 4,3 5,8 22,2 22 0,9 9 11 25 TUN7 Cap Serrat, Tunisia 5 28,5 32 22,8 3,9 6,7 20,3 10 0,6 8 7 25 TUN8 Cap Serrat, Tunisia 7 37,5 38 27,5 5 11,3 25,8 25,7 0,7 10 10 25 TUN9 Cap Serrat, Tunisia 4,5 27,5 34 18 5,1 8,8 24,8 15,7 1 5 5 25 TUN10 Cap Serrat, Tunisia 6,5 35 38 36 5,9 10,5 24,2 17,7 1 11 11 25 TUN11 Cap Serrat, Tunisia 5 30,5 40 22 4,3 8,2 26,8 19 0,5 9 7 25 TUN12 Cap Serrat, Tunisia 5 22 35 16,4 3,8 3,2 17,8 13,7 0,7 5 1 25 TUN13 Cap Serrat, Tunisia 3 23 37 16,7 3,7 5,2 21,3 8 0,7 3 0 25 TUN14 Cap Serrat, Tunisia 6 32 41,5 28,8 4,9 8,3 24,5 18 0,8 9 8 25 TUN15 Cap Serrat, Tunisia 6,5 33 34 20 4,2 6,5 24,2 12 0,7 4 5 25 TUN16 Cap Serrat, Tunisia 6 26,5 26 20,1 3,9 4,2 18,2 11,7 0,6 5 3 25 TUN17 Cap Serrat, Tunisia 6,5 47 56 32,3 4,8 12,7 31 23,7 1,7 12 10 25 TUN18 Cap Serrat, Tunisia 10 43 48 42 5,3 11,3 33,3 21,3 1 8 9 25 TUN19 Cap Serrat, Tunisia 7 38 41 28,3 4,7 7,7 22,7 15 0,7 6 10 25 TUN20 Cap Serrat, Tunisia 9 46,5 50 47 5,4 15,8 31,7 23 0,9 10 11 25 TUN21 Cap Serrat, Tunisia 7 44 45 38,3 4,6 12 25,8 22,3 1 10 12 25 TUN22 Cap Serrat, Tunisia 11 54,5 60 42,5 5,6 18 38,3 20,7 0,7 12 11 25 TUN23 Cap Serrat, Tunisia 7,5 38 43 35 4,8 8,7 16,3 25 1,1 10 7 25 TUN24 Cap Serrat, Tunisia 8 49,5 45 38 6 12,7 38,3 14 1,1 8 7 25 TUN25 Cap Serrat, Tunisia 6 41 49 28,1 5,2 12,8 31,8 13 1,5 5 9 25 TUN26 Cap Serrat, Tunisia 7 30 33 30 4,2 6,7 19,3 15,7 1,1 6 7 25 TUN27 Cap Serrat, Tunisia 7,5 38 44 44,2 5,1 12 27,3 10 1,1 9 7 25 TUN28 Cap Serrat, Tunisia 5,5 35 37 23 4,4 7,8 26,2 15 0,7 4 8 25 TUN29 Cap Serrat, Tunisia 7 38,5 50 34,4 6 14,8 32,2 20 1,4 12 12 25 TUN30 Cap Serrat, Tunisia 5 31 40 19 4,4 5,7 23 12 1,3 6 9 25 TUN31 Cap Serrat, Tunisia 3 27 34 16 3,4 5,5 24 11 1 3 3 25 SAR1 Porto Tangone, Sardinia 10 29,5 30 16 4,8 4,3 14 16,5 3,7 8 6 25 97Morphological and genetic variation of Chamaerops humilis (Arecaceae) in relation to the altitude Code Population H ei gh t o f t he st em ( cm ) H ei gh t o f t he pl an t ( cm ) C ro w n di am et er ( cm ) St em d ia m et er (m m ) Pe tio le w id th (c m ) Pe tio le w id th (c m ) Le af le ng th (c m ) Le af w id th (c m ) Le af th ic kn es s (m m ) N o. o f l ea f se gm en ts N o. th or ns o n th e pe tio le W ax c ov er ag e de ns ity % SAR2 Porto Tangone, Sardinia 3 19 22 11,5 3,1 2,7 12,5 9,5 2 4 1 25 SAR3 Porto Tangone, Sardinia 4,5 20,5 24 16,8 4,5 2,8 14,8 15,2 5 9 7 25 SAR4 Porto Tangone, Sardinia 4 22 12,5 12,5 4 1,3 17,7 9 4,3 5 0 35 SAR5 Porto Tangone, Sardinia 2,5 18,5 14 9,8 3,9 1 10,8 8,3 3,4 4 0 35 SAR6 Porto Tangone, Sardinia 5,5 21 21,5 12,7 3,6 2,3 12,8 10,2 5,7 5 5 35 SAR7 Porto Tangone, Sardinia 3,5 21 27,5 12,9 3,4 2,7 13,7 15,7 4,7 8 3 35 SAR8 Porto Tangone, Sardinia 3,5 20,5 26,5 14,8 3,9 2,7 15,5 15,8 9,3 5 0 30 SAR9 Porto Tangone, Sardinia 5 26 23 15,9 3 4 16 13,7 3,2 3 5 25 SAR10 Porto Tangone, Sardinia 4 26 27,5 23,8 3,9 4,5 16,7 17,3 4,3 11 5 25 SAR11 Porto Tangone, Sardinia 3 22,5 29,5 10,6 3 3,3 16,3 13,3 3,5 5 3 30 SAR12 Porto Tangone, Sardinia 4,5 28 26 18,5 4,8 5,3 19,8 17 3,7 8 7 35 SAR13 Porto Tangone, Sardinia 5 25 26,5 17 3,8 3,8 20 12,5 4,7 8 5 30 SAR14 Porto Tangone, Sardinia 4 32 27,5 9,9 4,5 4,5 22 13,7 4,5 5 3 35 SAR15 Porto Tangone, Sardinia 4,5 30 27,5 16,9 4,7 4,2 21,3 13 5,6 3 5 25 SAR16 Porto Tangone, Sardinia 6 27 23 22 3,8 3,6 18,9 14,3 4,7 5 3 25 SAR17 Porto Tangone, Sardinia 5 25 27,5 21,8 3,9 4,1 19,1 15 4,3 4 0 30 SAR18 Porto Tangone, Sardinia 4,5 19 26,5 10,7 4,5 4,5 22 13,6 4,7 8 5 30 SAR19 Porto Tangone, Sardinia 4 32 27,5 16,7 4,7 4,1 20,6 14,7 5,5 5 3 35 SAR20 Porto Tangone, Sardinia 6 22 27,5 10,4 3,8 3,8 17,3 11,6 4,7 5 3 40 SAR21 Porto Tangone, Sardinia 5 27 23 18,4 4 4,2 14,1 8,9 4 4 0 30 SAR22 Porto Tangone, Sardinia 4,5 25 27,5 16,9 4,5 4,5 16,3 15,4 5,6 5 3 25 SAR23 Porto Tangone, Sardinia 4 19 26,5 23 4,3 3,8 22,2 13,4 4,5 4 5 30 SAR24 Porto Tangone, Sardinia 6 31 19 17,5 3,8 3,6 19,5 16,2 4,7 5 5 35 SAR25 Porto Tangone, Sardinia 4 22 27,5 16,9 4,2 4,5 22,6 15,3 4,3 3 3 25 SAR26 Porto Tangone, Sardinia 4,5 24 26,5 20,3 4,5 4,2 19,4 16,3 4 4 0 30 SAR27 Porto Tangone, Sardinia 5 28 27,5 18,6 3,9 3,8 19,2 16,2 4,7 8 5 35 SAR28 Porto Tangone, Sardinia 3,5 31 23 17,5 3,8 3,6 22 14 3,8 5 0 30 SAR29 Porto Tangone, Sardinia 6 24 26,5 18,3 4,5 4,5 21,6 15,8 4,1 4 3 25 SAR30 Porto Tangone, Sardinia 5,5 28 23 17,4 4,1 4,1 23 15,8 4,6 5 5 30 SAR31 Porto Tangone, Sardinia 7 22 23 15,8 3,9 3,7 9,8 13,3 3,4 8 4 35 98 Antonio Giovino, Annalisa Marchese, Gianniantonio Domina Supplemental data file 2. Pearson correlation coefficients (r) among the 12 characters measured. All correlations were significant with p > 0.0001 (Student’s t test) with the lone exception of Leaf thikness. H stem H plant Crown diameter Stem diameter Petiole width Petiole length Leaf length Leaf width Leaf thikness No. leaf segments No. thorns Hair density H stem 3,42E-08 1,82E-08 3,39E-23 0.048467 1,14E-07 0.079418 1,98E-01 0.24308 7,31E-13 3,29E-06 0.0058902 H plant 0.4303 1,55E-41 7,09E-02 4,91E-22 9,76E-52 2,97E-45 1,70E-21 0.0277 0.0065374 1,04E-14 3,97E-13 Crown diameter 0.45465 0.77937 1,41E-06 7,02E-14 6,31E-52 3,46E-31 2,11E-15 0.18042 1,34E-02 2,91E-18 1,30E-04 Stem diameter 0.64769 0.29956 0.4178 0.3676 7,78E-10 0.44561 0.0001304 4,70E-02 3,28E-20 2,50E-03 9,37E-03 Petiole width 0.13412 0.63638 0.54079 0.061459 3,93E-12 9,67E-23 9,64E-12 6,58E-01 0.14084 5,07E-06 9,39E-19 Petiole length 0.4396 0.82722 0.82799 0.47882 0.51553 4,07E-33 8,69E-17 0.082782 4,18E-04 2,50E-19 7,00E-05 Leaf length 0.11934 0.79836 0.71441 0.052045 0.64331 0.72809 5,46E-16 0.013342 0.39458 3,73E-06 1,16E-26 Leaf width 0.28525 0.63096 0.56117 0.25682 0.49385 0.57859 0.55578 0.0043571 6,97E-04 1,80E-12 5,84E-03 Leaf thikness -0.079577 0.14947 -0.091265 -0.30507 0.26751 -0.11803 0.16776 0.19284 5,25E-01 0.14078 2,41E-05 No. leaf segments 0.52635 0.1841 0.32128 0.61759 0.1003 0.36163 -0.058079 0.35603 -0.27094 2,85E-05 1,18E-02 No. thorns 0.41007 0.53844 0.59605 0.34151 0.38371 0.60805 0.40892 0.52061 -0.10031 0.38944 0.0071865 Hair density 0.18638 -0.53018 -0.37405 0.32569 -0.60164 -0.38043 -0.67882 -0.33146 -0.39111 0.32287 -0.182