Swiss Mattenklee landraces,a distinct and diverse genetic resource of red clover (<Emphasis Type="Italic">Trifolium pratense</Emphasis> L.)

Genetic variability within and among 19 landraces and cultivars of red clover ( Trifolium pratense L.) was investigated by means of amplified fragment length polymorphism (AFLP) analysis in order to assess the potential value of Swiss Mattenklee landraces as genetic resources for plant breeding and the preservation of biodiversity. Populations were classified into three groups according to their origin and agronomic features: Mattenklee landraces (8), Mattenklee cultivars (8) and field clover cultivars (3). Analysis of molecular variance based on 276 polymorphic AFLP markers revealed 80% of total variability to be due to variability within populations while 12% were attributed to variability among groups. Stepwise discriminant analysis identified a subset of 126 AFLP markers which best separated individual plants into the three respective groups. Genetic distances between populations were considerably larger among groups than among populations within the same group, providing further evidence for the genetic distinction between Mattenklee landraces, Mattenklee cultivars and field clover cultivars. AFLP markers identified two landrace clusters, containing three and four populations respectively, which, together with one additional landrace, may sufficiently represent the genetic variability of all eight landraces investigated. The results of this study strongly suggest that Swiss Mattenklee landraces form a genetically distinct group of red clover. The data obtained provide criteria on how to efficiently manage, preserve and exploit Mattenklee germplasm.     

Genetic differentiation analysis of African cassava (Manihot esculenta) landraces and elite germplasm using amplified fragment length polymorphism and simple sequence repeat markers

Molecular‐marker‐aided evaluation of germplasm plays an important role in defining the genetic diversity of plant genotypes for genetic and population improvement studies. A collection of African cassava landraces and elite cultivars was analysed for genetic diversity using 20 amplified fragment length polymorphic (AFLP) DNA primer combinations and 50 simple sequence repeat (SSR) markers. Within‐population diversity estimates obtained with both markers were correlated, showing little variation in their fixation index. The amount of within‐population variation was higher for landraces as illustrated by both markers, allowing discrimination among accessions along their geographical origins, with some overlap indicating the pattern of germplasm movement between countries. Elite cultivars were grouped in most cases in agreement with their pedigree and showed a narrow genetic variation. Both SSR and AFLP markers showed some similarity in results for the landraces, although SSR provided better genetic differentiation estimates. Genetic differentiation (Fst) in the landrace population was 0.746 for SSR and 0.656 for AFLP. The molecular variance among cultivars in both populations accounted for up to 83% of the overall variation, while 17% was found within populations. Gene diversity (H_e) estimated within each population varied with an average value of 0.607 for the landraces and 0.594 for the elite lines. Analyses of SSR data using ordination techniques identified additional cluster groups not detected by AFLP and also captured maximum variation within and between both populations. Our results indicate the importance of SSR and AFLP as efficient markers for the analysis of genetic diversity and population structure in cassava. Genetic differentiation analysis of the evaluated populations provides high prospects for identifying diverse parental combinations for the development of segregating populations for genetic studies and the introgression of desirable genes from diverse sources into the existing genetic base.     

Genetic diversity in perennial ryegrass and white clover among old Dutch grasslands as compared to cultivars and nature reserves

To support conservation policies for old Dutch grasslands that are still in agricultural use, morphological variation and AFLP-based (amplified fragment length polymorphism-based) genetic diversity was studied in perennial ryegrass and white clover populations and compared with the diversity in reference varieties. In addition, AFLP variation was also studied in grasslands located in nature reserves. From principal component analysis (PCA), it appeared that date of ear emergence in perennial ryegrass and characters related to plant vigour in white clover were the main morphological characters separating the reference varieties from the old Dutch grassland populations, and some of the grassland populations from each other. In both species, intrapopulation variation was lower for the reference varieties. Lower heterogeneity within the reference varieties was also found in the AFLP analysis. All common AFLP's observed in old Dutch grasslands could also be found in the reference varieties and nature reserves. Only a small number of low-frequency alleles found in old Dutch grasslands were absent from the other two groups. However, band frequencies of markers could vary considerably between populations, which may have been caused by selection. Analysis of the AFLP data by PCA distinguished the majority of reference varieties from the old Dutch grasslands, and showed genetic differentiation only between some grasslands. Comparison of old Dutch grasslands with grasslands in nature reserves indicated that basically the same range of genetic variation is covered by the two groups. Our study indicates that the Netherlands harbour a more or less continuous population for major parts of the diversity of perennial ryegrass and white clover. It was concluded that no specific conservation measures are presently needed to maintain genetic diversity of perennial ryegrass and white clover occurring in old Dutch grasslands.     

Genetic relationship among wild,landraces and cultivars of hazelnut (Corylus avellana) from Portugal revealed through ISSR and AFLP markers

The genus Corylus, a member of the birch family Betulaceae, includes several species that are widely distributed throughout temperate regions of the Northern Hemisphere. This study assesses the genetic diversity in 26 international cultivars and 32 accessions of Corylus avellana L. from Portugal: 13 wild genotypes and 19 landraces. The genetic relationships among the 58 hazelnuts (Corylus avellana L.) were analyzed using inter simple sequence repeat (ISSR) and amplified fragment length polymorphism (AFLP) markers. Eighteen ISSR primers and seven AFLP primer pairs generated a total of 570 unambiguous and repeatable bands, respectively, from which 541 (95.03 %) were polymorphic for both markers. Genetic similarity index values ranged from 0.239 for wild types and cultivars to 0.143 for landraces and wild types. The genetic relationships were presented as a Neighbor-Joining method dendrogram and a two-dimensional principal coordinate analysis (PCoA) plot. The Neighbor-Joining dendrogram showed three main clusters, and the PCoA analysis has shown to be congruent with the hierarchical analysis. Bayesian analysis clustered all individuals into three groups showing a good separation among wild genotypes, landraces and cultivars. The genetic diversity found on wild genotypes and Portuguese landraces may provide relevant information for the diversity conservation and it will be useful in breeding programs and to identify local selections for preservation.     

Genetic diversity in cultivars and landraces of Oryza sativa subsp. indica as revealed by AFLP markers.

Genetic diversity among 49 Indian accessions of rice (Oryza sativa subsp. indica), including 29 landraces from Jeypore, 12 modern cultivars, and 8 traditional cultivars from Tamil Nadu, was investigated using AFLP markers. In total, nine primer combinations revealed 664 AFLPs, 408 of which were found to be polymorphic. The percentage of polymorphic AFLPs was approximately the same within the cultivars and landraces. Similar results were obtained when genetic diversity values were estimated using the Shannon-Weiner index of diversity. Genetic diversity was slightly higher in the modern cultivars than in the traditional cultivars from Tamil Nadu. Among the landraces from Jeypore, the lowland landraces showed the highest diversity. The present study showed that the process of breeding modern cultivars did not appear to cause significant genetic erosion in rice. Cluster analysis and the first component of principle component analysis (PCA) both showed a clear demarcation between the cultivars and landraces as separate groups, although the genetic distance between them was narrow. The modern cultivars were positioned between the landraces from Jeypore and the traditional cultivars from Tamil Nadu. The second component of PCA further separated medium and upland landraces from lowland landraces, with the lowland landraces found closest to the traditional and modern cultivars.     

Genetic diversity among cultivars, landraces and wild relatives of rice as revealed by microsatellite markers

Genetic diversity among 35 rice accessions, which included 19 landraces, 9 cultivars and 7 wild relatives, was investigated by using microsatellite (SSR) markers distributed across the rice genome. The mean number of alleles per locus was 4.86, showing 95.2% polymorphism and an average polymorphism information content of 0.707. Cluster analysis based on microsatellite allelic diversity clearly demarcated the landraces, cultivars and wild relatives into different groups. The allelic richness computed for the clusters indicated that genetic diversity was the highest among wild relatives (0.436), followed by landraces (0.356), and the lowest for cultivars. Allelic variability among the SSR markers was high enough to categorize cultivars, landraces and wild relatives of the rice germplasm, and to catalogue the genetic variability observed for future use. The results also suggested the necessity to introgress genes from landraces and wild relatives into cultivars, for cultivar improvement.     

AFLP and pedigree-based genetic diversity estimates in modern cultivars of durum wheat [ Triticum turgidum L. subsp. durum (Desf.) Husn.

A substantial amount of between and within cultivar genetic variation was detected in all the 13 registered modern Canadian durum wheat (Triticum turgidum L. ssp. durum (Desf.) Husn.) cultivars based upon amplified restriction fragment polymorphism (AFLP). Of the approximately 950 detected AFLP markers, only 89 were polymorphic, with 41 between cultivars whereas the remaining 48 showed polymorphism within at least one cultivar. The ancestry of Canadian durum wheat cultivars was traced back to 125 cultivars, selections, and breeding lines including 17 landraces. Mean pair-wise genetic distance based on the kinship coefficient was 0.76. On the other hand, AFLP-based mean pair-wise genetic distance was 0.40. Even though there was a large difference between the means of the two diversity measures, a moderate positive correlation (r=0.457, p<0.002) was detected between the two distance matrices. Cluster analysis with the entire AFLP data divided all cultivars into three major groups reflecting their breeding origins. One group contained ’Pelissier’ alone, which was a selection from a landrace introduced into the US from Algeria. On the other hand such groupings among cultivars were not evident when KIN was used for genetic diversity measures instead. The level of genetic variation among individuals within a cultivar at the breeders’ seed level was estimated based on an inter-haplotypic distance matrix derived from the AFLP data. We found that the level of genetic variation within the most-developed cultivars is fairly substantial despite rigorous selection pressure aimed at cultivar purity in breeding programs. Comparison of AFLP and pedigree-based genetic diversity estimates in crop species such as durum wheat can provide important information for plant improvement. Received: 26 January 2001 / Accepted: 31 May 2001     

Diversity distribution and population structure of tea germplasms in China revealed by EST-SSR markers

Tea plant (Camellia sinensis (L.) O. Kuntze) originated from China, where distributed abundant genetic resources. It is of critical importance to well understanding of genetic diversity and population structure for effective collection, conservation, and utilization of tea germplasms. In this study, 96 new polymorphic EST-SSR markers were developed and used to analyze 450 tea accessions collected from 14 tea-producing regions across China. A total of 409 alleles were observed, and the gene diversity (H) and polymorphic information content (PIC) were estimated to be averagely 0.64 and 0.61, respectively, across all the tested samples. The higher level of genetic diversity was observed in original regions like Guangxi, Yunnan, and Guizhou provinces. The allele number, H, and PIC showed decreasing trend when the region was more and more away from origin center of tea plant, which gave us implications on the spreading route of tea plant in China. The clustering of 450 samples both showed a clear separation according to their geographic origin based on either model simulation or genetic distance. The genetic differentiation was further analyzed among five inferred populations represented different eco-geographic regions. The lowest F _st and the closest relationship were revealed between proximal populations, which indicated that gene exchanges occurred frequently between nearby regions than distance ones. The majority of genetic variation resulted from differentiation within population (81.36%) rather than among inferred (13.6%) and regional (5.04%) populations based on analysis of molecular variance. Our study also revealed that the lower diversity and simpler population structure were found in improved cultivars than wild teas and landraces, which indicated that genetic base of developed cultivars became narrow because of long-standing domestication and artificial selection. So more attentions should be focused to conserve and utilize the beneficial genes in wild teas and landraces to broaden genetic variation of new cultivars in future breeding of the tea plant.     

The origin of Russian cultivars of red clover ( Trifolium pratense L.) and their genetic relationships to wild populations in the Urals

Propagation and breeding of red clover ( Trifolium pratense L.) in Russia was initiated about 200 years ago but the origin of present-day cultivars is disputed. Some authors argue that most Russian cultivars were derived from western European ones, whereas others support a Russian origin of the cultivars from local wild populations. In the present study we assessed the genetic variation at 17 allozyme loci in seven Russian cultivars, bearing the names of localities of the Urals, two American ones that have been used in Russia for scientific experiments and seven wild populations of the Urals and Western Siberia. Variation at the 17 protein loci supports the western European origin of the cultivars and also indicates that gene flow between cultivars and wild populations was limited or has not acted sufficiently long to affect the genetic composition of the red clover wild populations of the Urals.     

Genetic Structure of Remnant Populations and Cultivars of Switchgrass (Panicum virgatum) in the Context of Prairie Conservation and Restoration

Switchgrass (Panicum virgatum L.) is a dominant, perennial C₄ grass of North American tallgrass prairies with cultivars that are widely used in grassland restoration, pastures, and landscaping. However, these cultivars may be genetically dissimilar to small, remnant populations, raising concerns about altered genetic composition of native populations through gene flow. To address this issue on a local scale in Ohio and Illinois, we used microsatellite markers to characterize genetic diversity and differentiation of 10 remnant prairie populations (5 in each state) and 8 common cultivars. The bulk of genetic variation was found to reside within rather than among wild populations, consistent with the outcrossing breeding system of switchgrass. Genetic diversity was similar among the remnant populations despite large differences in area (approximately 2–2,590 ha), highlighting the importance of small native populations as reservoirs of variation and potential seed sources for prairie restoration. Cultivars generally had similar levels of variation to the wild populations, but we found clear genetic dissimilarity between wild and cultivated gene pools (especially for Kanlow, but also Trailblazer, Blackwell, Dacotah, Summer, and Sunburst cultivars). This suggests that using cultivars in local prairie restoration efforts may alter the genetic composition of wild populations. Whether such changes are deemed as negative depends on the cultivar under consideration and specific conservation goals for preserving native switchgrass populations. Patterns of genetic variation in remnant prairie populations and potential cultivar sources can be used to develop guidelines for restoration as well as future planting of cultivars for biofuels.     

Analysis of genetic diversity in red clover (Trifolium pratense L.) breeding populations as revealed by RAPD genetic markers.

Red clover is an important forage legume species for temperate regions and very little is known about the genetic organization of its breeding populations. We used random amplified polymorphic DNA (RAPD) genetic markers to address the genetic diversity and the distribution of variation in 20 breeding populations and cultivars from Chile, Argentina, Uruguay, and Switzerland. Genetic distances were calculated for all possible pairwise combinations. A high level of polymorphism was found and the proportion of polymorphic loci across populations was 74.2%. A population derived from a non-certified seedlot displayed a higher proportion of polymorphic loci than its respective certified seedlot. Gene diversity values and population genetics parameters suggest that the populations analyzed are diverse. An analysis of molecular variance (AMOVA) revealed that the largest proportion of variation (80.4%) resides at the within population level. RAPD markers are a useful tool for red clover breeding programs. A dendrogram based on genetic distances divided the breeding populations analyzed into three distinct groups. The amount and partition of diversity observed can be of value in identifying the populations that parents of synthetic cultivars are derived from and to exploit the variation available in the populations analyzed.     

Genetic variation in the endangered wild apple (Malus sylvestris (L.) Mill.) in Belgium as revealed by amplified fragment length polymorphism and microsatellite markers

The genetic variation within and between wild apple samples (Malus sylvestris) and cultivated apple trees was investigated with amplified fragment length polymorphisms (AFLP) and microsatellite markers to develop a conservation genetics programme for the endangered wild apple in Belgium. In total, 76 putative wild apples (originating from Belgium and Germany), six presumed hybrids and 39 cultivars were typed at 12 simple sequence repeats (SSR) and 139 amplified fragment length polymorphism (AFLP) loci. Principal co-ordinate analysis and a model-based clustering method classified the apples into three major gene pools: wild Malus sylvestris genotypes, edible cultivars and ornamental cultivars. All presumed hybrids and two individuals (one Belgian, one German) sampled as M. sylvestris were assigned completely to the edible cultivar gene pool, revealing that cultivated genotypes are present in the wild. However, gene flow between wild and cultivated gene pools is shown to be almost absent, with only three genotypes that showed evidence of admixture between the wild and edible cultivar gene pools. Wild apples sampled in Belgium and Germany constitute gene pools that are clearly differentiated from cultivars and although some geographical pattern of genetic differentiation among wild apple populations exists, most variation is concentrated within samples. Concordant conclusions were obtained from AFLP and SSR markers, which showed highly significant correlations in both among-genotypes and among-samples genetic distances.     

A hierarchical analysis of population genetic structure in Rhizobium leguminosarum bv. trifolii

Little is known about the population processes that shape the genetic diversity in natural populations of rhizobia. A sample of 912 Rhizobium leguminosarum biovar trifolii isolates were collected from naturalized red clover populations ( Trifolium pratense ) and analyzed for 15 allozyme loci to determine the levels and distribution of genetic diversity. Hierarchical analyses compared different sampling levels, geographical separation, and temporal separation. Total genetic diversity across all isolates was H = 0.426, with 57.6% of the total diversity found among isolates obtained from individual red clover plants. Relatively low genetic differentiation among populations and high differentiation among plants within populations was observed; this suggests that gene flow and founder effect act differently at geographical and local scales. Significant differences were observed in (i) allele frequencies among populations and among plants within populations, and (ii) the frequency distribution of the most widespread and the most abundant strains. When multilocus linkage disequilibrium was calculated, significant levels of disequilibrium were observed in the total sample and in three of the eight populations.     

Unlocking the diversity of genebanks: whole-genome marker analysis of Swiss bread wheat and spelt

Key message

High-throughput genotyping of Swiss bread wheat and spelt accessions revealed differences in their gene pools and identified bread wheat landraces that were not used in breeding.

Abstract

Genebanks play a pivotal role in preserving the genetic diversity present among old landraces and wild progenitors of modern crops and they represent sources of agriculturally important genes that were lost during domestication and in modern breeding. However, undesirable genes that negatively affect crop performance are often co-introduced when landraces and wild crop progenitors are crossed with elite cultivars, which often limit the use of genebank material in modern breeding programs. A detailed genetic characterization is an important prerequisite to solve this problem and to make genebank material more accessible to breeding. Here, we genotyped 502 bread wheat and 293 spelt accessions held in the Swiss National Genebank using a 15K wheat SNP array. The material included both spring and winter wheats and consisted of old landraces and modern cultivars. Genome- and sub-genome-wide analyses revealed that spelt and bread wheat form two distinct gene pools. In addition, we identified bread wheat landraces that were genetically distinct from modern cultivars. Such accessions were possibly missed in the early Swiss wheat breeding program and are promising targets for the identification of novel genes. The genetic information obtained in this study is appropriate to perform genome-wide association studies, which will facilitate the identification and transfer of agriculturally important genes from the genebank into modern cultivars through marker-assisted selection.

     

Assessment of genetic diversity and relationships among maize (<Emphasis Type="Italic">Zea mays</Emphasis> L.) Italian landraces by morphological traits and AFLP profiling

In the present study we have analyzed the genetic diversity pattern in a sample of 54 Italian maize landraces, using morphological traits and molecular markers. Although the 54 landraces surveyed in this study were restricted to Lombardy, the core region of maize production in Italy, our data revealed a large genetic heterogeneity for both morphological and molecular traits in the accessions analyzed. Additionally, our data confirm that the AFLP markers produced a high frequency of polymorphic bands and were able to unequivocally fingerprint each of the landraces considered. Cluster analysis based on AFLP markers displayed a clearer separation of the accessions in comparison to morphological data. Different populations were divided into four major clusters reflecting the geographical origin and seasonal employment of the landraces analyzed. Molecular analysis of variance showed significant (P < 0.01) differences among groups, among populations within groups, and among individuals within populations. Approximately 74% of the total variance could be attributed to differences within populations. Conversely, a lower level of differentiation was detected among groups (~4%). Regarding population structures, the genetic distance between populations (F _ST = 0.25 ± 0.3) and the degree of inbreeding within groups (F _SC = 0.22 ± 0.2), did not diverge significantly, while both significantly differed from the degree of relatedness between markers within groups (F _CT = 0.04 ± 0.03). Results are discussed in relation to a suitable conservation method.     

AFLP analysis of genetic diversity within and among Coffea arabica cultivars

Genetic diversity of Coffea arabica cultivars was estimated using amplified fragment length polymorphism (AFLP) markers. Sixty one Coffea accessions composed of six arabica cultivars, including Typica, Bourbon, Catimor, Catuai, Caturra and Mokka Hybrid, plus two diploid Coffea species, were analyzed with six EcoRI- MseI primer combinations. A total of 274 informative AFLP markers were generated and scored as binary data. These data were analyzed using cluster methods in the software package NTSYSpc. The differences among cultivars at the DNA level were small, with an average genetic similarity of 0.933. Most accessions within a cultivar formed a cluster, although deviant samples occurred in five of the six cultivars examined due to residual heterozygosity from ancestral materials. Among the six cultivars fingerprinted, the highest level of genetic diversity was found within the cultivar Catimor, with an average genetic similarity of 0.880. The lowest level was found within Caturra accessions, with an average genetic similarity of 0.993. Diversity between C. arabica and two other Coffea species, Coffea canephora and Coffea liberica, was also estimated with average genetic similarities of 0.540 and 0.413, respectively, suggesting that C. canephora is more closely related to C. arabica than is C. liberica. The genetic variation among arabica cultivars was similar to the variation within cultivars, and no cultivar-specific DNA marker was detected. Although arabica cultivars appear to have a narrow genetic base, our results show that sufficient polymorphism can be found among some arabica cultivars with a genetic similarity as low as 0.767 for genetic/QTL mapping and breeding. The assessment of genetic diversity among arabica cultivars provided the necessary information to estimate the potential for using marker-assisted breeding for coffee improvement.     

Phylogenetic relationships among wild and cultivated Tartary buckwheat (Fagopyrum tataricum Gaert.) populations revealed by AFLP analyses

Phylogenetic relationships among cultivated landraces and natural populations of wild subspecies of Tartary buckwheat were investigated at the individual level by constructing a phylogenetic tree based on amplified fragment length polymorphism (AFLP) markers. Seven individuals from seven cultivated landraces and 35 individuals from 21 natural populations of wild subspecies were utilized for AFLP analyses. Three groups were recognized: (1) all cultivated landraces and wild subspecies from northern Pakistan, central and eastern Tibet, and northwestern Yunnan, (2) wild subspecies from central and southern Sichuan, (3) wild subspecies from northern Sichuan and eastern Tibet. It was concluded that cultivated Tartary buckwheat probably originated in eastern Tibet or northwestern Yunnan in China.     

Analysis of Relationship Between Genetic Diversity and Taxol Content of Taxus wallichiana var. wallichiana in Different Provenance

We studied the relationship between genetic diversity and taxol content of Taxus wallichiana var. wallichiana using AFLP and HPLC . The results of AFLP fingerprinting indicated that two patterns were discovered among seven populations. Through PopGene 1 . 31 and Arlequin 3. 1 software , stable genetics within population and significant differentiation among populations (F_st = 0. 67 ) were revealed . However, taxol content was markedly different within and among populations when testing the one-year twigs . Among wild forests, the highest taxol content was found in Luxi population which average percentage was 0. 0185%. While the taxol content level was low in Tengchong and Yongde populations , which were 0. 0049% and 0. 0087% respectively . The cultivated population in Lufeng showed the highest taxol content level which was 0. 0225% comparing with that in the populations of wild forests. There were relations between genetic diversity and taxolcontent at the population level to some extent , while no corresponding relations were found at the individual level .     

Domestication and the distribution of genetic variation in wild and cultivated populations of the Mesoamerican fruit tree Spondias purpurea L. (Anacardiaceae)

Domestication occurs as humans select and cultivate wild plants in agricultural habitats. The amount and structure of variation in contemporary cultivated populations has been shaped, in part, by how genetic material was transferred from one cultivated generation to the next. In some cultivated tree species, domestication involved a shift from sexually reproducing wild populations to vegetatively propagated cultivated populations; however, little is known about how domestication has impacted variation in these species. We employed AFLP data to explore the amount, structure, and distribution of variation in clonally propagated domesticated populations and sexually reproducing wild populations of the Neotropical fruit tree, Spondias purpurea (Anacardiaceae). Cultivated populations from three different agricultural habitats were included: living fences, backyards, and orchards. AFLP data were analysed using measures of genetic diversity (% polymorphic loci, Shannon's diversity index, Nei's gene diversity, panmictic heterozygosity), population structure (F(ST) analogues), and principal components analyses. Levels of genetic variation in cultivated S. purpurea populations are significantly less than variation found in wild populations, although the amount of diversity varies in different agricultural habitats. Cultivated populations have a greater proportion of their genetic variability distributed among populations than wild populations. The genetic structure of backyard populations resembles that of wild populations, but living fence and orchard populations have 1/3 more variability distributed among populations, most likely a reflection of relative levels of vegetative reproduction. Finally, these results suggest that S. purpurea was domesticated in two distinct regions within Mesoamerica.     

Distinction between cultivated and wild chicory gene pools using AFLP markers

The cultivation area of industrial chicory, Cichorium intybus L. cv Sativum, coincides with the natural distribution area of its wild relative, C. intybus L., which could lead to gene flow between wild and cultivated types. The genetic diversity within and between the two types has therefore been studied using AFLP genotyping of samples from 12 wild populations collected in Belgium and ten commercial varieties. The genotyping of 233 individuals allowed the identification of 254 AFLP markers. Similar levels of genetic diversity were observed within wild populations and cultivated varieties, suggesting the absence of any strong bottleneck in the history of the cultivated types. The phylogenetic analysis pointed to a monophyletic origin of cultivated varieties as compared to the local wild populations studied, hence the two types of chicory form two separate gene pools. The genotyping of some individuals sampled in ruderal sites clearly showed that they belong to the cultivated gene pool, which suggests the existence of feral or weedy types. The low differentiation observed among wild populations indicates that gene flow might be important in this species.