genetic diversity of tunisian date palms (phoenixdactylifera l.) revealed by nuclear microsatellite...

Genetic diversity of Tunisian date palms (Phoenix dactylifera L.)revealed by nuclear microsatellite polymorphism

SALWA ZEHDI1, MOKHTAR TRIFI1, NORBERT BILLOTTE2, MOHAMED MARRAKCHI1 and

JEAN CHRISTOPHE PINTAUD3

1Laboratoire de Genetique Moleculaire, Immunologie & Biotechnologie, Faculte des Sciences de Tunis, Campus

Universitaire, El Manar I, Tunis, Tunisia2CIRAD (Centre de cooperation Internationale en Recherche Agronomique pour le Developpement), UMR 1096

Polymorphismes d’Interet Agronomique, Montpellier, France3IRD (Institut de Recherche pour le Developpement), UMR DGPC/DYNADIV, Montpellier, France

Zehdi, S., Trifi, M., Billotte, N., Marrakchi, M. and Pintaud, J. C. 2004. Genetic diversity of Tunisian date palms

(Phoenix dactylifera L.) revealed by nuclear microsatellite polymorphism. */ Hereditas 141: 278�/287. Lund, Sweden. ISSN

0018-0661. Received March 9, 2004. Accepted October 26, 2004

Fourteen microsatellite loci of Phoenix dactylifera were targeted to examine the genetic diversity in Tunisian date-palms

germplasm. They showed a high level of polymorphism in 49 accessions from three main oases with little geographic

structure within Tunisia. The microsatellite data agrees with previous analyses of Tunisian germplasm using other molecular

markers. 100% of local date-palms accessions were successfully fingerprinted and easily distinguished by the help of only

three loci. The possibility of using microsatellites for large scale molecular labelling of offshoots and in vitro plantlets and

their implication in the plant material certification is discussed.

Mokftar Trifi, Laboratoire de Genetique Moleculaire, Immunologie & Biotechnologie, Faculte des Sciences de Tunis, Campus

Universitaire, El Manar I, Tunis, Tunisia. E-mail: [email protected]

Date-palm (Phoenix dactylifera L), a long-lived dioe-

cious monocotyledon (2n�/36), is the major factor of

oases environmental and economic stability (RHOUMA

1994). In Tunisia, this important subtropical fruit crop

is currently in danger due to severe genetic erosion as a

consequence of the predominance of the elite cultivar

Deglet Nour in modern cultures (RHOUMA 1994).

This tendency led to the disappearance of many

cultivars with medium and low fruit qualities. It is

therefore imperative to elaborate a strategy aiming at

the evaluation of the genetic diversity and the pre-

servation of the Tunisian date-palm germplasm. Many

studies have been designed on this matter and

described the use of either morphological traits

or isozyme makers to identify the Tunisian date-

palm varieties (REYNES et al. 1994; RHOUMA 1994;

BOUABIDI et al. 1996; OULD MOHAMED SALEM

et al. 2001). However, most morphological traits are

highly influenced by environmental conditions or vary

with the development stage of plants, and isozymes are

limiting due to low levels of polymorphism. Conse-

quently, DNA based techniques have been developed

and proved effective to assess genetic diversity, be-

cause they provide a nearly unlimited potential of

markers to uncover differences at the molecular level.

Data based on molecular markers such as RFLPs,

RAPDs and ISSRs have been performed to character-

ize date-palm genotypes (CORNICQUEL and MERCIER

1994, 1996; SEDRA et al. 1998; BEN ABADALLAH et al.

2000; TRIFI et al. 2000; TRIFI 2001; ZEHDI et al. 2002,

SAKKA et al. 2004). These studies have permitted to

identify markers suitable for identification of date-

palm varieties. However, the search of many other

markers is required to obtain a deeper comprehension

of the genetic organization in Tunisian date-palm

germplasm.Microsatellites or simple sequence repeats (SSRs)

consist of variable numbers of tandemly repeated units

each one of 1 to 6 bp, and represent a class of

repetitive DNA commonly found in eukaryotic gen-

omes (TAUTZ and RENZ 1984). They are characterized

by their great abundance (CONDIT and HUBBELL

1991; RODER et al. 1995), high variability (SCHUG

et al. 1998) and large distribution throughout different

genomes (LIU et al. 1996; TARAMINO and TINGEY

1996; RODER et al. 1998). Microsatellites are typically

multi-allelic loci since more than five alleles per locus

are commonly observed either in populations of plants

(INNAN et al. 1997; SENIOR and HEUN 1998) or in

animals (MACHUGH et al. 1997). In addition, auto-

mated polymerase chain reaction (PCR) based tech-

niques, which enable high throughput data collection

and good analytical resolution at a low cost, have been

developed for microsatellites (KRESOVICH et al. 1995;

MITCHELL et al. 1997). Hence, taking into account

these advantages, microsatellites are actually one of

the preferred genetic markers in plants and animals.

They are exploited as tools to assess genetic distances

Hereditas 141: 278�/287 (2004)

and genetic diversity in evolutionary studies

(BRUFORD and WAYNE 1993; GOLDSTEIN and

POLLOCK 1997).

In the present article, we report the use of the SSR

markers to survey polymorphisms and identify geno-

types within Tunisian date-palms.

MATERIAL AND METHODS

Plant material

We have used a set of 49 accessions listed in Table 1.They consisted of 42 cultivars and 7 male plants,

collected from three main oases namely: Tozeur,

Gabes and Kebili, and one individual from Kerkennah

islands (Fig. 1). Cultivars were chosen for their good

fruit quality and are the most common genotypes in

the main plantations located in the south of Tunisia.

Other fruit characteristics and morphological traits for

most varieties were reported by RHOUMA (1994).Among these varieties, two that were recently intro-

duced in Tozeur (‘‘Zehdi’’ from Iraq and ‘‘Ghars

Mettig’’ from Algeria) are included in the study (as

part of the Tozeur sampling).

The plant material consists of young leaves of adult

trees randomly sampled from the mentioned oases.

DNA preparation

Total cellular DNA was extracted from frozen young

leaves using DNAeasy Plant Mini Kit (Qiagen S.A.,

Table 1. List of the 49 Tunisian date-palm accessions

used in this study.

Oasis Group Label Accession

Tozeur (popT) 001 Deglet Nour,, ,, 002 Boufagous,, ,, 003 Ftimi,, ,, 004 Kenta,, ,, 005 Kintichi,, ,, 006 Deglet Bey,, ,, 007 Ghars Mttig,, ,, 008 Zehdi,, ,, 009 Arichti,, ,, 010 Khouftimi,, ,, 011 Horra,, ,, 012 Okhet Degla,, ,, 024 Hamra,, ,, 026 Kharroubi,, ,, 027 Angou,, ,, 028 Bejjou,, ,, 029 Goundi,, ,, 030 Halwaya,, ,, 031 Tazerzit Safra,, ,, 032 Tazerzit Soda,, ,, 033 Ammari,, ,, 034 Besser Hlo,, ,, 035 Mahmoudia,, ,, 036 Chodak,, ,, 037 Rhaimya,, ,, 038 Om lal,, ,, 039 Om essayed,, ,, 040 Bidh Hmam,, ,, 041 Gasbi,, ,, 048 CIV

Male (popM) 013 T124,, ,, 014 T138,, ,, 015 T158,, ,, 016 T169,, ,, 017 DF1,, ,, 018 DG9,, ,, 047 T159

Gabes (popG) 019 Rochdi,, ,, 020 Lemsi,, ,, 021 Bouhattam,, ,, 022 Smiti,, ,, 023 Denga,, ,, 025 Aguiwa

Kebili (popK) 042 Deglet Nour K,, ,, 043 Kechdou ahmar,, ,, 044 Fhal Ksebba,, ,, 045 Rakli,, ,, 046 Fermla

Kerkennah 049 TamriFig. 1. Distribution area of date-palms in Tunisia.

Hereditas 141 (2004) Genetic diversity of Tunisian date palms 279

Courtaboeuf, France) according to manufacturer’s

protocol. After purification, DNA concen-

trations were determined using a GeneQuant

spectrometer (Amersham Pharmacia Biotech, France)

and quality was checked on agarose minigel electro-

phoresis according to SAMBROOK et al. (1989).

Microsatellites amplification

We have tested a total of 16 date-palms specific primer

pairs developed by BILLOTE et al. (2004).

PCR reactions were performed in a total reaction

mixture of 10 ml containing: 20�/30 ng of total cellular

DNA (1 ml) as template, 1.5 mM of MgCl2, 1�/PCR

buffer (Promega Corp. Madison, USA), 0.2 mM of

dNTP PCR mix (Promega), 0.625 U of Taq DNApolymerase (Promega) and 0.2 mM of primers and

using reverse primer 5? end labelled with a fluorescent

M13 tail. Amplifications were performed in a Biome-

tra Thermocycler (Biometra GmbH, Goettingen,

Germany) with the following conditions: a denatura-

tion step of 5 min at 958C followed by 35 cycles of 30 s

at 958C, 1 min at 528C and 1 min at 728C, and a final

extension step at 728C for 7 min. A negative control,with the reaction mixture excluding DNA, was also

included in each experiment.

SSR genotyping

SSRs were screened on Li-Cor IR2 automated

DNA sequencer (Li-Cor, Lincoln, NE, USA) byloading 0.2 ml of PCR product diluted 10�/ in loading

buffer, on 6.5% polyacrylamide gel. Automatic geno-

Table 2. Summary of 14 microsatellite loci revealed in

the Tunisian date-palms genotypes studied.

Locus Allele size Alleles Genotypes

mPdCIR10 142�/181 8 16mPdCIR15 142�/157 7 11mPdCIR16 148�/156 4 7mPdCIR25 219�/250 7 14mPdCIR32 302�/318 8 16mPdCIR35 200�/214 5 7mPdCIR50 172�/222 8 19mPdCIR57 260�/288 8 15mPdCIR63 139�/171 5 8mPdCIR70 205�/227 7 15mPdCIR78 138�/173 10 22mPdCIR85 175�/197 8 21mPdCIR90 162�/193 7 12mPdCIR93 181�/202 8 18

Table 3. Expected (Hexp) and observed (Hobs) Heterozygosity in each group by locus computed using Genetix. Bold

numbers correspond to the lowest and highest values of Hexp in all accessions.

Locus PopT PopK PopG PopM All accessions

mPdCIR10 Hexp 0.75 0.42 0.81 0.54 0.73Hobs 0.67 0.60 1.00 0.57 0.69

mPdCIR15 Hexp 0.71 0.64 0.40 0.62 0.68Hobs 0.70 0.40 0.50 0.43 0.59

mPdCIR16 Hexp 0.60 0.66 0.61 0.49 0.60Hobs 0.67 0.60 0.83 0.57 0.67

mPdCIR25 Hexp 0.73 0.58 0.57 0.70 0.72Hobs 0.83 0.60 0.83 0.14 0.71

mPdCIR32 Hexp 0.76 0.82 0.78 0.66 0.77Hobs 0.67 1.00 0.67 0.86 0.71

mPdCIR35 Hexp 0.45 0.32 0.28 0.24 0.40Hobs 0.33 0.00 0.33 0.00 0.26

mPdCIR50 Hexp 0.75 0.78 0.74 0.65 0.75Hobs 0.77 0.60 0.83 0.71 0.73

mPdCIR57 Hexp 0.71 0.66 0.74 0.50 0.71Hobs 0.67 0.20 0.67 0.29 0.57

mPdCIR63 Hexp 0.64 0.42 0.28 0.72 0.63Hobs 0.23 0.60 0.33 0.14 0.26

mPdCIR70 Hexp 0.71 0.78 0.72 0.72 0.75Hobs 0.30 0.20 0.00 0.29 0.26

mPdCIR78 Hexp 0.77 0.68 0.72 0.78 0.79Hobs 0.73 0.80 1.00 0.57 0.73

mPdCIR85 Hexp 0.83 0.80 0.78 0.76 0.83Hobs 0.73 0.80 1.00 0.57 0.75

mPdCIR90 Hexp 0.69 0.58 0.61 0.49 0.68Hobs 0.67 0.80 0.83 0.57 0.69

mPdCIR93 Hexp 0.80 0.70 0.72 0.72 0.80Hobs 0.90 0.60 0.83 0.86 0.86

280 S. Zehdi et al. Hereditas 141 (2004)

Fig. 2. Histograms illustrating the miocrosatellite alleles frequencies’ distribu-tion in four groups of Tunisian date-palms.


typing and allele size scoring were performed by the

SAGA-GTTM software (Li-Cor, Lincoln, NE, USA).

Data analysis

The sampling was subdivided into three geographical

groups of cultivars (female), a group composed by the

male individuals, and one additional accession from

Kerkennah islands. Estimates of total genetic diversity

were conducted on all individuals but the Kerkennah

accession was excluded from population level analysesthat required multiple samples per population.

For each group of date-palm genotypes, the genetic

diversity was estimated by the determination of the

allelic diversity (total number of alleles, allele fre-

quency per group), the observed and expected hetero-

zygosity (Hobs and Hexp) (NEI 1987). The total genetic

diversity (Ht), the mean genetic diversity within

population (Hs) and the genetic differentiation amongpopulations (Gst) were also calculated using the

program Genetix 4.04 (BELKHIR et al. 2000). The

allelic richness corresponding to the evaluated number

of alleles independently from the sample size, was

assessed using FSTAT 2.9.1 (GOUDET 1995). A

Wilcoxon-Mann-Whitney test was applied to differ-

entiate the allelic richness scored values using

STATISTICA 6.0 (STATSOFT Inc, 2001).

Data were also computed using GENEPOP 3.1(RAYMOND and ROUSSET 1995) and FSTAT 2.9.1

programs to test pairwise linkage equilibria (LE) at all

loci over the four groups to calculate Fis and pairewise

estimates of Fst according to the formula of WEIR and

COCKERHAM (1984).

In order to compute ordinations and hierarchical

classifications, we calculated the shared allele distance:

Das (CHAKRABORTY and JIN 1993) using Populations1.2.28 Software (LANGELLA 2002). This genetic dis-

tance is known to be appropriate for recently diverged

populations (GOLDSTEIN and POLLOCK 1997). The

distance matrix obtained was used as input file for

Neighbour program (FELSENSTEIN 1995), to construct

the dendrogram using the neighbor-joining (NJ) algo-

rithm. Bootstrap values were computed over 100

replications using MSA 3.10 (DIERINGER andSCHLOTTERER 2003). In addition, the individual

microsatellite genotypes scores were coordinated in a

bi-dimensional space by principal coordinate analysis

(PCO) by computing the Das distance matrix with

STATISTICA 6.0 (STATSOFT Inc, 2001).

Cultivar identification key

Ecotype identification was performed as follows:

genotypes were hierarchically organized according to

the greater number of alleles per locus respectively

recorded for mPdCIR78, mPdCIR85 and mPdCIR25.Accessions were then classified and those of similar

fingerprints were grouped.

RESULTS

Genetic diversity analysis

Among the 16 primer pairs tested for their ability to

generate expected SSR banding patterns in Tunisian

data-palms, 14 successfully established the genotypes

of the 49 accessions. Locus mPdCIR48 did not

amplify in our sampling and locus mPdCIR44 pro-

duced erratic amplifications as it was originally

reported (BILLOTTE et al. 2004). The SSR profiles

exhibited more than four different alleles per locus in

Table 4. Genetic diversity indices for the four groups.

Group Hexp Hnb Hobs FIS P value Mean number of alleles/locus

PopT 0.71 0.72 0.63 0.1222 0.0000 6.79PopK 0.63 0.70 0.56 0.2258 0.0983 4.00PopG 0.63 0.68 0.69 �/0.0140 0.7789 4.00PpopM 0.62 0.66 0.47 0.3083 0.0001 3.71All accessions 0.70 0.71 0.61 0.142 0.0000 7.14

Table 5. The total gene diversity (Ht), the mean gene

diversity within population (Hs) and the genetic differ-

entiation among groups (Gst) estimated using the

program Genetix 4.04.

Locus Hs Ht Gst

mPdCIR10 0.6294 0.6851 0.0813mPdCIR15 0.5945 0.6307 0.0574mPdCIR16 0.5901 0.6039 0.0229mPdCIR25 0.6456 0.7123 0.0937mPdCIR32 0.7540 0.7940 0.0504mPdCIR35 0.3239 0.3346 0.0320mPdCIR50 0.7299 0.7556 0.0340mPdCIR57 0.6525 0.7093 0.0801mPdCIR63 0.5163 0.5734 0.0996mPdCIR70 0.7333 0.7697 0.0473mPdCIR78 0.7367 0.8034 0.0831mPdCIR85 0.7914 0.8374 0.0549mPdCIR90 0.5933 0.6594 0.1003mPdCIR93 0.7378 0.7703 0.0422Multilocus 0.6449 0.6885 0.0633


the sampling, with homozygous and heterozygous

individuals clearly identifiable. A total of 100 alleles

with a mean of 7.14 alleles per locus were scored

(Table 2). The number of alleles per locus varied from

4 (mPdCIR16) to 10 (mPdCIR78).

Hexp values (Table 3) ranged from 0.40 (mPdCIR35)

to 0.83 (mPdCIR85) indicating that the Tunisian date-

palms collection is characterised by a high degree of

genetic diversity.

Allele frequencies distributions at the 14 loci are

reported in Fig. 2. Both alleles number and frequen-

cies vary among the Tunisian subgroups. This is well

exemplified in locus mPdCIR90 which exhibits seven

alleles in Tozeur oasis, four of them are not found in

the remaining subgroups. Moreover, the mean number

of alleles varied from one group to another (Table 4).

However, there are no significant differences in allelic

richness among the four groups (P�/0.15). This result

Fig. 3. NJ dendrogram of 49 Tunisian date-palm accessions constructed with Dasgenetic distance based on 100 microsatellite alleles. Bootstrap values indicated onbranches have been computed over 100 replications.


agrees with multilocus means of expected heterozygo-

city (Hexp) and unbiased heterozygocity (Hnb) that did

not significantly differed among groups at P�/0.05

(Table 4).

Total gene diversity (Ht), estimates of the mean gene

diversity within groups (Hs), and the genetic differ-

entiation among groups (Gst) are reported in Table 5.

For all the 14 loci studied, the Hs and Ht values are

nearly similar suggesting that the maximum of varia-

bility is locally maintained. This assumption is con-

firmed by the low values of Gst. For instance, the

multilocus values of Hs, Ht and Gst are 0.6449, 0.6885

and 0.0633 respectively. We may therefore assume that

only 7% of the variability is explained at the inter-

group level, while 93% of this variability is maintained

at the intra�/group level (Table 5).

Fis values estimated according to the formula of

WEIR and COCKERHAM (1984) and tested with an

exact test (RAYMOND and ROUSSET 1995) are re-

ported in Table 4. Two groups: Tozeur and males

genotypes, showed a significant deviation from Hardy-

Weinberg equilibrium (HWE). A specific test for

heterozygote deficiency (U test, ROUSSET and

RAYMOND 1995) indicated statistically significant

deficits for the two groups. The two other groups

Gabes and Kebili showed non deviation from HWE. A

global test across all loci and groups using Fisher

exact method indicated a significant deviation from

HWE, the specific test for heterozygote deficiency

indicated statistically highly significant deficits.

A derived NJ dendrogram based on Das genetic

distance, exhibited three main clusters each one is

composed of males as well as cultivars (Fig. 3).Noteworthy, the two Deglet Nour and the two Arichti

accessions originated from different date-palm oases

are strongly clustered and suggested that these culti-

vars correspond to similar genotypes. In addition, the

observed clustering topology showed that groupings

of accessions are made independently either from their

geographic origin or the sex of trees. This result is

corroborated by the absence of geographic structure inthe plotting of accessions on the two first PCO axes

(Fig. 4). Moreover, pairwise comparisons of the

multilocus Fst values scored among the pre-established

groups were not significant (P�/0.05), indicating that

all groups revealed high genetic affinity (Table 6).

Cultivar identification key

For each date-palm accession, the detected genotypes

for mPdCIR78, mPdCIR85 and mPdCIR25 micro-

satellites loci were scored. A total of 25 alleles were

identified in these loci: 10 alleles labelled (a1 to a10)

for the mPdCIR78 locus, 8 alleles denoted (b1 to b8)

for the mPdCIR85 and 7 alleles (c1 to c7) for themPdCIR25 locus. Taking in consideration the identi-

fied alleles, we have established an ecotype identifica-

tion key (Fig. 5). As described above, this precise

diagram confirmed our assumptions about the Deglet

Nour and Arichti accessions since they have presented

identical genotypes. In fact, these cultivar accessions

exhibited identical fingerprints across all the micro-

satellite loci examined. Consequently, the constructedidentification key permitted to unambiguously discri-

minate 47 over 47 accessions studied (100%). This

result confirms the ability of microsatellites to finger-

print genotypes. Theoretically, a maximum of 55 440

different multilocus genotypes would been distin-

guished taking in account the three mentioned loci

(i.e. mPdCIR78, mPdCIR85 and mPdCIR25).

DISCUSSION

In the present article, we performed SSR genotyping

method in order to examine the genetic diversity in

Tunisian date-palms. Data exhibited evidence of the

axe2

(10

,64%

)PCO

axe1 (13,81%)

popT

popM

popG

popK

Fig. 4. Principal coordinate analysis (PCO) scores ofindividual microsatellite genotypes using Das genetic dis-tance in Tunisian date-palms.

Table 6. Pairwise comparisons of the multilocus Fst

values.

Group PopT PopM PopG PopK

PopT 0.0000PopM 0.0095 0.0000PopG 0.0202 0.0492 0.0000PopK �/0.0219 �/0.0144 �/0.0193 0.0000


utility of this technology to enlarge the number of

markers suitable for evidencing molecular polymorph-

isms in this crop. As a result, a large number of SSRalleles have been revealed with a mean of 7.14 per

locus and permitted to detect a relatively high degree

of genetic variability in this crop. In fact, the scored

values of diversity are higher at the intra group level

than at the inter groups level. Similar results have been

reported in Moroccan, Algerian and Tunisian date-

palm cultivars using isozyme markers (TORRES and

TISSERAT 1980; BENNACEUR et al. 1991, FAKIR 1992;

OULD MOHAMED SALEM et al. 2001). These results

are also comparable to those reported in other long-

lived cultivated species such as olive (OUAZZANI et al.

1995) and fig (SALHI-HANNACHI et al. 2004). Taking

into account our present data together with priorisozyme information (OULD MOHAMED SALEM et al.

2001) the genetic diversity seems to be high in Tunisian

date-palms. This could be attributed to the dioecious

nature of this crop.

Tozeur and males groups showed significant deficit

of heterozygocity. However, the two other remaining

groups (Gabes and Kebili) showed no deviation from

HWE. This result can be explained by the stronger

selection operated in Tozeur oasis compared to Kebili

and Gabes oases.

Fig. 5. Identification key of 49 Tunisian date-palm genotypes based on 3 microsatellite locusfingerprints.


In addition, analysis of the genetic diversity struc-

ture has exhibited spatial organisation of accessions

typically continuous and independent from both the

geographic origin or the sex of trees. Using RAPDand ISSR markers, similar results have been reported

in date-palms (SEDRA et al. 1998, TRIFI et al. 2000;

ZEHDI et al. 2002). These authors have suggested a

common genetic basis among date-palms genotypes in

spite of their distinctiveness by morphometric para-

meters, particularly those related to the fruit traits.

Hence, our data suggest the existence of one ancestral

date-palm population and are in agreement with theunique Mesopotamian domestication origin of this

crop (WRIGLEY 1995).

On the other hand, farmers are currently faced to

distinguish among cultivars clonally propagated by

offshoots. The use of vegetative and fruiting charac-

teristics (RHOUMA 1994) or the isozyme markers

(OULD MOHAMED SALEM et al. 2001) are less

rewarding since these traits are limited in numberand highly influenced by the environmental conditions

or the development stages. Fortunately, the revealed

SSR alleles were successfully used to molecularly

discriminate a nearly unlimited number of date-palms

cultivars. Compared to studies reported in date-palms,

the scored percentage of resolution is higher than

observed using isoenzymes (BOOIJ et al. 1995; OULD

MOHAMED SALEM et al. 2001) and plastid DNAhaplotypes (SAKKA 2003). These authors have re-

ported 69%, 93% and 71% resolving power values

respectively. Consequently, our results provided neu-

tral molecular markers powerfully suitable in cultivar

identification. Their transfer to other laboratories over

the world would be of great interest to label at a large

scale offshoots, any other plant material at early stage

and in vitro plantlets. Our data provide evidence of thepossibility of using these powerful markers as descrip-

tors in the certification and the control of origin labels

of date-palm material.

Acknowledgements �/ This work was supported by grantsfrom the Tunisian Ministere de l’Enseignement Superieur, dela Recherche Scientifique et de la Technologie.

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genetic diversity of tunisian date palms (phoenixdactylifera l.) revealed by nuclear microsatellite...

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