Diversity of native rice (Oryza Poaceae:) species of Costa Rica

We found several populations of wild Oryza species in the lowlands of Costa Rica. The plants showed extensive morphological variation, suggesting the presence of several species. In the morphologic study, 33 traits were scored for plants of all the species. A principal component analysis revealed the significant morphological separation of the different species. The analyses indicated that there are three species, O. grandi­glumis, O. latifolia and O. glumaepatula. Two putative hybrid types were found, both significantly differing in their morphology from the known species and intermediate at several traits. O. grandi­glumis is a new record for Costa Rican flora. Its main population is located in Caño Negro Wildlife Refuge, Los Chiles, Alajuela. O. latifolia is distributed throughout the lowlands of the country and the plants of the Atlantic slope are significantly bigger in general habit than those of the Guanacaste area. During this study a population of O. glumaepatula of hundreds of thousands of plants was discovered in the Medio Queso River wetland, Los Chiles, Alajuela. This population is the most important source of genes for cultivar's improvement from the primary gene pool of rice in Costa Rica. The small ligule and the wide flag leaf characteristic of the two CCDD species separated them from the AA diploid O. glumaepatula. Seed size, ligule size, number of branches in the panicle, plant height and sterile lemma length are all bigger in O. grandi­glumis, and influenced the second factor that separated the CCDD species in two discrete clusters. The species found offer great possibilities for the improvement of rice cultivars and they should be thoroughly studied and appropriately protected.     

Cross-species Transferability of Rice Microsatellites in its Wild Relatives and the Potential for Conservation Genetic Studies

Here, we investigated the transferability of 60 microsatellite markers characterized for cultivated rice Oryza sativa L. in three wild Oryza species representing different genome types: O. rufipogon Griff. (AA), O. officinalis Wall. et Watt. (CC), and O. granulate Nees et Arn. ex Watt. (G). The results indicate the 60 rice SSR loci tested produced homologous amplification products to different extents in O. rufipogon (100%), O. officinalis (90%) and O. granulata (73.3%). Proportions of polymorphism for successfully amplified loci ranged from 0.983 via 0.667 to 0.364 in O. rufipogon, O. officinalis and O. granulata, respectively. The utility of these microsatellite markers was tested for the characterization of genetic diversity in 117 genotypes of these four Oryza species. The values of genetic diversity in cultivated rice are higher than the other two wild species O. officinalis and O. granulata, suggesting microsatellites tend to have more variability in the focal species than in non-focal species to which they are applied. However, much lower levels of genetic variation were observed in rice than in its wild progenitor O. rufipogon, which indicates severe loss of genetic variation may reflect the ‘domestication bottleneck’ through which rice passed. The observation that most of the rice microsatellites are able to detect allelic polymorphisms at different extent in Oryza species suggest that rice microsatellite loci should be useful for the analysis of genetic diversity and inter- and intra-specific relationships in the genus. Therefore, high rates of successful cross-amplification of rice microsatellites among Oryza species with different genome types will offer excellent opportunities to investigate the population genetic structure of wild rice species and explore their conservation genetics.     

Use of the bulked genomic DNA-based RAPD methodology to assess the genetic diversity among abandoned Korean tea plantations

The variability of 20 abandoned Korean tea plantations was investigated using the RAPD methodology and thebulked DNA procedure. Out of 50 primers screened, 13 revealed diversity among the populations and generated26 polymorphic markers in all. Two and two populations were indistinguishable from each other and in general,the diversity detected among the populations was relatively low. The genetic distance calculated from theJaccard's variability index varied from 0 to 0.79 with an average of 0.44. The low genetic diversity found in thisstudy could be explained by the narrow genetic base of the Korean tea populations introduced from MainlandChina, by the short history and relatively homogeneous environment of the populations, by mass destruction oflocal tea plantations in the 14th century and by the reproductive mode of Camellia sinensis. Indeed, Camellia sinensis being a highly outcrossing species maintains high intrapopulationnal variability as compared to itsinterpopulation variability. In the light of the results obtained, a strategy for local tea conservation is discussed.     

Genetic diversity of wild banana (<Emphasis Type="Italic">Musa balbisiana</Emphasis> Colla) in China as revealed by AFLP markers

Wild banana Musa balbisiana Colla is one of the progenitors of cultivated bananas and plantains. It is native to Southeast Asia and the western Pacific. South China represents the northern limit of its distribution range. The genetic diversity of Musa balbisiana was assessed by the amplified fragment length polymorphism (AFLP) fingerprinting in 15 populations of China. Four primer pairs produced 199 discernible loci. High levels of genetic diversity were detected, with P = 78.5%, H _E = 0.241, and H _pop = 0.3684 at population level, and P = 100%, H _T = 0.3362 and H _sp = 0.5048 at species level. Significant genetic differentiation among populations was detected based on Hickory’s analysis (27.6%), Shannon’s diversity index (27.0%) and AMOVA (27.1%). The AFLP results are discussed and compared with data obtained by microsatellites method. The estimates of genetic diversity and differentiation between each pair of populations computed with microsatellites and AFLP markers were not significantly correlated. Conservation strategies for Musa balbisiana in China are proposed.     

Spatial and temporal dynamics in genetic diversity in upland rice and late millet (<Emphasis Type="Italic">Pennisetum glaucum</Emphasis> (L.) R. Br.) in The Gambia

Ambiguity exists about the level of genetic diversity represented by farmer crop varieties, how it develops over time and how it relates to the diversity comprised by formal varieties. As part of an interdisciplinary technological/sociological study on farmer management of gene flow, upland rice (Oryza sativa L.) and late millet (Pennisetum glaucum (L.) R.Br.) from The Gambia were investigated for morphological and molecular variation. The goal of these analyses was to obtain insight into the level of crop genetic diversity of farmer’s materials planted in several case study villages in The Gambia. For both crops, samples were collected from villages and various research institutes. Based on variety names, different rice and millet varieties were expected to be used in different villages. In fact, there was a large overlap in genetic diversity for both crops, masked by the use of synonyms. The considerable similarity in rice genetic diversity between villages most likely results from the exchange of varieties between farmers. For millet this seems the result of development of varieties from the same gene pool. Some farmer varieties of rice, however, are apparent hybrid forms between the species O. sativa and O. glaberrima Steud., and farmer varieties in general displayed higher levels of genetic diversity than formal varieties. This indicates that, for rice, genetic diversity develops in farmers’ fields and may have potential use in formal breeding programs.     

Assessment of genetic diversity in cultivars and wild accessions of Luohanguo (<Emphasis Type="Italic">Siraitia grosvenorii</Emphasis> [Swingle] A. M. Lu et Z. Y. Zhang), a species with edible and medicinal sweet fruits endemic to southern China,using RAPD and AFLP markers

Genetic variation of wild populations and cultivars of Luohanguo (Siraitia grosvenorii), a plant species endemic to southern China, was assessed using random amplified polymorphic DNA (RAPD) and amplified fragment length polymorphism (AFLP) markers. Based on the results for 130 individuals from seven populations, a high level of genetic diversity of Luohanguo was observed at the species level. The percentage of polymorphic loci (P) was 89.4%, Nei’s gene diversity (H _e) was 0.239, and Shannon’s information index (H _o) was 0.373 based on the combined AFLP and RAPD data. There was a high degree of genetic differentiation, with 45.1% of the genetic variation attributed to differences between the populations. The genetic diversity of the Luohanguo cultivars is much lower than that of wild populations (P = 41.8%, H _e = 0.141, H _o = 0.211), and a distinct genetic differentiation is observed between the cultivars and wild accessions. The pool of genetic variation in the wild populations provides an excellent gene resource for Luohanguo breeding.     

Genetic diversity and conservation of two endangered eggplant relatives (<Emphasis Type="Italic">Solanum vespertilio</Emphasis> Aiton and <Emphasis Type="Italic">Solanum lidii</Emphasis> Sunding) endemic to the Canary Islands

Solanum vespertilio Aiton and Solanum lidii Sunding are endemic, endangered wild species from the Canary Islands. These species are of potential value for eggplant (S. melongena) breeding, given that they are part of the secondary genepool of this crop. We study genetic diversity with amplified fragment length polymorphisms (AFLPs) markers from 5 populations of S. vespertilio (47 samples) and 3 of S. lidii (26 samples). Five related African species (S. dasyphyllum Schumach. et Thonn., S. delagoense Dunal, S. campylacanthum Hochst., S. panduriforme E. Mey, S. aff. violaceum Ortega) were also included in the analysis. A total of 235 AFLP markers included 178 and 156 that were polymorphic in S. vespertilio and S. lidii, respectively. Analysis of genetic distance, phenograms, and principal component plots showed that these rare Canarian species are differentiated (G _ST = 0.412) from the continental materials and that Solanum vespertilio is more distinct to its African congeners than is S. lidii. There is a relatively high level of differentiation between the two species (G _ST = 0.373), that presumably reflects geographic restrictions (S. lidii to Gran Canaria; S. vespertilio essentially to Tenerife). However, both species have similar levels of total diversity. We speculate that the combination of the many unusual reproductive features (andromonoecy, zygomorphy, heteranthery and weak enantiostyly in S. vespertilio) help explain genetic diversity that is high for self compatible species. The high genetic diversity may also indicate populations were larger in the past. A decrease in population size could contribute to the relatively low genetic differentiation among the populations. The data presented herein provide the foundation for initiation of ex situ and in situ conservation programs for these wild relatives of eggplant. This paper is dedicated to the memory of Dr. Richard N. Lester, who made significant contributions to the taxonomy, biosystematics and conservation of genetic resources of African species of Solanum.     

Genetic diversity associated with conservation of endangered Dongxiang wild rice (<Emphasis Type="Italic">Oryza rufipogon</Emphasis>)

The wild progenitor species (Oryza rufipogon) of Asian cultivated rice (O. sativa L.) is located in Dongxiang county, China which is considered its the northernmost range worldwide. Nine ex situ and three in situ populations of the Dongxiang wild rice (DXWR) and four groups of modern cultivars were genotyped using 21 SSR markers for study of population structure, conservation efficiency and genetic relationship. We demonstrated that the ex situ conservation of the DXWR failed to maintain the genetic identity and reduced genetic diversity. Therefore, in situ conservation is absolutely necessary to maintain the genetic identity, diversity and heterozygosity. Also, in situ conservation is urgently needed because natural populations in DXWR have decreased from nine to three at present due to farming activity and urban expansion. In DXWR, the three surviving in situ populations had greater expected heterozygosity than any cultivated rice, and were genetically closer to japonica than either the male-sterile maintainer or restorer lines, or indica. Japonica has the lowest genetic diversity of cultivated rice. As a result, DXWR is a rich gene pool and is especially valuable for genetic improvement of japonica rice because these O. rufipogon accessions are most closely related to the japonica as compared to O. rufipogon collected anywhere else in the world.     

RAPD-based Analysis of Genetic Diversity and Selection of Lingonberry (<Emphasis Type="Italic">Vaccinium vitis-idaea</Emphasis> L.) Material for <Emphasis Type="Italic">ex situ</Emphasis> Conservation

Random amplified polymorphic DNA markers were used to assess relatedness and genetic diversity for 15 lingonberry (Vaccinium vitis-idaea) populations. Seven primers yielding 59 polymorphic bands were used to analyse 13 populations, representing ssp. vitis-idaea from Sweden, Finland, Norway, Estonia and Russia, and two populations, representing ssp. minus from Japan and Canada. A cluster analysis and a multidimensional scaling analysis (MDS) showed similar phenetic patterns among populations, with a pronounced geographic grouping in most cases. Significant correlations were obtained between geographic and genetic distances for the entire set of populations as well as for the 13 ssp. vitis-idaea populations. Mean within-population diversity was 0.206 when estimated with Lynch and Milligan's index, and 0.431 when estimated with Shannon's index, which is in agreement with the mixed mating system reported for lingonberry. Within-population variability accounted for 68.6% of the total variance when all populations were included, and for 78.8% when only populations of ssp. vitis-idaea were analysed. Two different approaches were applied to the selection of plant material for a potential gene bank: (1) a hierarchical sampling strategy based on a cluster analysis and (2) the Maximum genetic diversity program, developed for the establishment of core collections. Random sampling was undertaken for comparisons with the selected data sets. The most diverse and representative set of lingonberry specimens was obtained when samples were selected with the Maximum diversity program.     

Microsatellite Markers Revealed the Genetic Diversity of an Old Japanese Rice Landrace ‘Echizen’

Landraces of rice (Oryza sativa L.) are valuable sources of genetic variation that have been lost in advanced cultivars. Seeds of a rice landrace stored for almost 100 years were found on Sado Island in Niigata prefecture, Japan. This report aims to present basic data on the genetic variation of this landrace, which was known as ‘Echizen’. Five samples of ‘Echizen’, consisting of two old samples, one sample maintained on farm, and two lines regenerated from old seeds were compared with other advanced cultivars and landraces using 19 microsatellite markers. Among the five samples of Echizen, the two stored samples showed greater diversity than the other samples. Cluster analysis based on the UPGMA method also showed that old Echizen was a diverse landrace that could cover the genetic diversity of most Japanese rice cultivars.     

Diversity in Phenotypic Profiles in Landrace Populations of Vietnamese Rice: A Case Study of Agronomic Characters for Conserving Crop Genetic Diversity on Farm

Phenotypic variation of agronomic characters in aromatic rice (Oryza sativa L.) was analyzed in order to elucidate the genetic diversity of the populations of rice landraces. Thirteen populations in Namdinh province, in the Red River Delta of Vietnam, were studied in both of farmers fields and an experimental field. Only small differences were found in agronomic characters among the populations, including populations containing different varieties. Variations among the populations in the frequency distributions of several characters suggested different degrees of diversity among the populations even among populations with the same variety name. The phenotypic profiles of farmers fields were different from those in an experimental field suggesting the environmental differences between them. One variety cultivated in the Myloc district had different phenotypic characters from the other varieties in the Haihau district more clearly in the experimental field. Since the small phenotypic variation in each of farm might be due to the genetic drift and selection by the farmers, on farm conservation of the landraces of rice is considered to be under a force to decrease phenotypic diversity. The present study suggests that the targeting several farms with different phenotypic profiles contribute to the conservation of regional genetic diversity of the landraces of rice.     

Genetic and demographic responses of fragmented Acacia dealbata (Mimosaceae) populations in southeastern Australia

Genetic and demographic studies of fragmented populations of common plant species often reveal negative impacts that are likely to constrain persistence. Examining species that are broadly representative of functional groups within fragmented landscapes is one approach to providing a better understanding of how these processes will influence vegetation persistence. Acacias are a significant component of the Australian flora, with Acacia dealbata being a common and representative species of fragmented landscapes across New South Wales. Previous reproductive assessments of fragmented A. dealbata populations indicated significant constraints for small populations through low reproductive output mediated by fertilisation success. This study examined genetic diversity, mating system, and progeny growth parameters of the seed crops produced by these populations to assess whether further constraints to persistence could be detected. Spatially explicit simulation studies were also conducted to assess the persistence likelihood of fragmented populations. Landscape parameters such as population size and plant density were useful predictors for some of the genetic and demographic responses, but a poor response signal was generally observed. Strong evidence for a self-incompatibility mechanism was observed in A. dealbata and is likely to be the major driver of population persistence. Self-incompatibility in small populations limits mate availability and eliminates inbred progeny early in the reproductive cycle leading to poor reproductive output. The simulation data provides further evidence that mate limitation in smaller populations (<200 plants and 40 S alleles) constrains reproductive output and persistence. These data indicate that introducing new germplasm to smaller populations can dramatically improve their persistence likelihood.     

Analysis of Genetic Diversity Among Saccharum spontaneum L. From Four Geographical Regions of India, Using Molecular Markers

Saccharum spontaneum L. a wild relative of sugarcane is the most variable and diverse among the Saccharum species. This species had been successfully exploited in sugarcane improvement programmes since 1915 and most of the present day commercial varieties are derivatives of interspecific hybrids involving S. spontaneum. The S. spontaneum germplasm available today in the World collections is diverse and represent different geographical groups. In the present investigation, an attempt was made to characterize 40 S. spontaneum clones collected from 4 different geographical areas in India using 20 random, 2 ISSR and 2 telomere primers. Of the 491 bands generated by these primers 83.9% were polymorphic. The genetic diversity estimated based on these markers was found to be moderate (48.9%). The pair-wise genetic distance between the accessions ranged from 29.8 to 60.0. The accessions from Arunachal Pradesh were found to be the most diverse, while Tamil Nadu accessions showed relatively less diversity. Diversity between Tamil Nadu and Kerala collections was found to be low, while the diversity between the Orissa group and the rest was found to be high. The collections from Mayurbanj and Cuttack regions of Orissa were found to be distinct. Arunachal Pradesh accessions, being more diverse, are a potential source for exploitation in sugarcane breeding programmes.     

Species Diversity in Wheat Landrace Populations from two Regions of Ethiopia

Wheat (Triticum spp.) landrace populations in Ethiopia are mostly species mixtures. However, no quantitative data is available with regard to their species components. We studied here 32 wheat landrace populations originating from two regions (Bale and Wello). A total of 2559 individual plants, 45–110 plants representing each population, were classified into their species components. Five tetraploid (2n = 4x = 28) and one hexaploid (2n = 6x = 42) wheat species were found in mixtures of varying proportions. These included the tetraploids Triticum durum Desf., Triticum turgidum L., Triticum aethiopicum Jakubz., Triticum polonicum L., Triticum dicoccon Schrank and the hexaploid Triticum aestivum L. Also found, however in a rare frequency, in two populations from Wollo was T. durum Desf. convar. durocompactoides Flaksb. (Triticum pyramidale Percival), which is a very dense spiked durum. Discriminant analysis using seven qualitative traits revealed 91.5% correct classification of the wheat species, beak awn and awn length with the most significant importance. Single species were found in eight of the populations; six were for T. durum and two for T. aethiopicum. Two to three species-combinations were the most frequent; a maximum of four species was recorded in one population. The highest diversity index (H′) observed was 0.44. T. durum was the most predominant species. The hexaploid T. aestivum was found in nine of the Wollo populations and, in one population, its frequency reached up to 35.5%. On altitudinal basis, no clear trend of clinal variation was observed both from the frequency distributions and H′ estimates. The results confirmed that Ethiopian wheats, despite the morphological overlaps, could be classified into their species components with high degree of certainty. For the future, therefore, genetic diversity estimations should be dissolved into their species components for more expeditious utilization and conservation of this important genetic resource.     

Genetic diversity in <Emphasis Type="Italic">Eremostachys superba</Emphasis> Royle ex Benth. (Lamiaceae), an endangered Himalayan species,as assessed by RAPD

Eremostachys superba Royle ex Benth. (Lamiaceae) has undergone a severe decline in population size since its discovery in the North-western Himalayas in late 19th century. One hundred and seventy-two plants from six populations in the Indian states of Uttar Pradesh and Jammu & Kashmir, located between 0.45 km and 455.72 km apart from each other were evaluated for RAPD polymorphism. Sixteen random primers generated 92 bands overall, 77 of which were polymorphic. Shannon’s index of genetic diversity within populations (H _o) ranged between 0.305 and 0.421; the average within-population diversity (H _pop) was 0.389; and the total species diversity (H _sp) was 0.478. The population from Mohand (representing the type locality) had the fewest plants, at 18, and was genetically the most depauperate. Among the other populations, ranging in size between 52 and 1,022 individuals, no relation between population size and genetic diversity was evident. It is suggested that these six populations represent relics of a larger, extended population, in which the presence of perennating rootstocks has helped preserve historic patterns of genetic diversity. AMOVA revealed that 83.01% of the variation exists within populations, which was consistent with earlier studies on the reproductive biology of E. superba, which indicated this species is predominantly allogamous. FST distances between all populations were significant, indicating geographic differentiation despite some of them being closely separated. Habitat restoration and protection from indiscriminate harvesting are proposed as primary strategies for conserving E. superba. Rejuvenation of the Mohand population through intrapopulation crossing between plants bearing diverse molecular phenotypes is also suggested.     

Diversity and phylogenetic analysis in Cocos nucifera L. in Mexico

The diversity and phylogenetic analysis in 22 populations of Mexican coconut and six imported populations, were estimated using 15 enzymatic systems and the allele frequencies in: peroxidase (PER), endopeptidase (ENP), and glucose 6-Phosphate dehydrogenase (G6PD). There was very low polymorphism, not more than two alleles per locus. The Wright fixation indexes F(it) = 0.62, F(is) = 0.40, and F(st) = 0.36 indicated low total heterosygosity and low heterosygosity within populations suggesting endogamy and genetic drift, and a high diversity among populations due to differentiation between Pacific and Gulf of Mexico coastal populations. The phylogenetic tree with values for genetic distance, indicated three groups on the Pacific coast related to Rennell Tall and Polynesian Tall, and two groups on the coast of the Gulf of Mexico, one related to West African Tall and another related to Mexican Pacific coast populations. This corroborates historical antecedents and morphological and physiological patterns. The Dwarf coconuts related to the Pacific Tall populations, Rennell Tall and Polynesian Tall. There was no difference between local and imported Dwarf populations.     

Isozyme studies of genetic diversity and evolution in Hippophae

Summary To provide information on the genetic variation, differentiation and evolution in Hippophae seed samples of 25 populations from China, Finland and Russia were electrophoretically analyzed. Of six loci investigated, four were good genetic markers for identifying species and subspecies. The percentages of polymorphic loci per population were 40.3% and 62.5% at 0.95 and 0.99 polymorphic criteria respectively. The mean number of alleles per locus per population was 2.1. Total genetic diversity in the material was 0.4614. Genetic diversity partitioning showed that there was a large amount of diversity residing within geographical populations (0.1354), between subspecies within species (0.1046) and between species (0.2566) but not between geographical populations (0.0114). There were nearly twice as many negative fixation indices as positive ones in Hippophae populations. The phylogenetic tree agreed very well with botanic classifications of the species and subspecies and their geographical distributions, and quantitatively presented the genetic relationships of 25 populations. A detailed view of the evolutionary stages in Hippophae showed clearly a general decline of similarity as evolutionary divergence continued, which further explained the evolution process in Hippophae.     

Genetic diversity of <Emphasis Type="Italic">Guizotia abyssinica</Emphasis> (L. f.) Cass. (Asteraceae) from Ethiopia as revealed by random amplified polymorphic DNA (RAPD)

Genetic diversity of 70 populations of niger (Guizotia abyssinica) representing all its growing regions in Ethiopia was investigated using random amplified polymorphic DNA (RAPD) to reveal the extent of its populations genetic diversity. Ninety-seven percent of the loci studied was revealed to be polymorphic for the whole data set. The within population diversity estimated by Shannon diversity index and Nei gene diversity estimates was revealed to be 0.395 and 0.158, respectively. The extent of genetic variation of populations from major niger producing regions was significantly lower than that of populations from other regions; however, it is distributed regardless of altitude of growth. Genetic differentiation between populations was estimated with Shannon index as G^′ _ST (0.432), Nei’s G _ST (0.242) and AMOVA based F _ST (0.350) and appears to be equivalent to the average values calculated from various RAPD based studies on outcrossing species. Higher proportion of the variation detected by AMOVA resided within populations (64.58%) relative to the amount of variation among populations (35.42%). UPGMA cluster analysis showed that most of the populations were clustered according to their region of origin. However, some populations were genetically distant from the majority and seem to have unique genetic properties. It is concluded that the crop has a wide genetic basis that may be used for the improvement of the species through conventional breeding and/or marker assisted selection. Collection of germplasm from areas not yet covered and/or underrepresented is the opportunity to broaden the genetic basis of genebank collection.     

Genetic Diversity in Tunisian Ceratonia siliqua L. (Caesalpinioideae) Natural Populations

The last two centuries witnessed the human-caused fragmentation of Tunisian Ceratonia siliqua L. (Caesalpinoideae) populations which were often represented by scattered individuals. Seventeen populations growing in four bioclimatic zones: sub-humid, upper semi-arid, mean semi-arid and lower semi-arid zones, were sampled for allozyme diversity to assess their genetic diversity and structuration using eight isozymes revealed by starch gel electrophoresis. The species showed high diversity within populations. The average number of alleles per polymorphic locus was 1.98, the percentage of polymorphic loci was 83.4% and the mean observed heterozygosity (Ho) and expected heterozygosity (He) under Hardy–Weinberg equilibrium were respectively 0.247 and 0.316. A substantial level of inbreeding within populations induced by Wahlund effect, was observed (F_IS = 0.231). High diversity resulted from the great number of genotypes in the ancestral population before fragmentation, favoured by the outbreeding of the species. High differentiation and low gene flow were detected among populations (F_ST = 0.200) and among pairs of ecological zones (0.113< F_ST <0.198). However, the differentiation coefficient of the four zones was low (F_ST = 0.085) and similar to the average F_ST for forest trees. Population structuration depends on geographic distance between sites rather than bioclimate, indicating that structuration has occurred slowly and that climatic conditions have had little effect. Nei's genetic distances (D) between populations were low and ranged from 0.004 to 0.201. Mean D value for all population was 0.087. The UPGMA clustering established for all populations through Nei's genetic distances did not clearly show that, for the majority of populations, grouping had resulted from ecological factors or geographic location. The substantial differentiation and the high genetic similarities between populations indicate that populations have been recently isolated as a result of anthropic pressure. In-situ conservation strategies must first focus on populations with a high level of genetic diversity and rare alleles. Appropriate conservation action should take account of bioclimatic zones. Ex-situ preservation should be based on a maximum number of individuals collected within populations in each ecological group and their propagation in different bioclimates by means of cuttings.