RAPD polymorphism of wild emmer wheat populations, Triticum dicoccoides, in Israel

 Genetic diversity in random amplified polymorphic DNAs (RAPDs) was studied in 110 genotypes of the tetraploid wild progenitor of wheat, Triticum dicoccoides, from 11 populations sampled in Israel and Turkey. Our results show high level of diversity of RAPD markers in wild wheat populations in Israel. The ten primers used in this study amplified 59 scorable RAPD loci of which 48 (81.4%) were polymorphic and 11 monomorphic. RAPD analysis was found to be highly effective in distinguishing genotypes of T. dicoccoides originating from diverse ecogeographical sites in Israel and Turkey, with 95.5% of the 100 genotypes correctly classified into sites of origin by discriminant analysis based on RAPD genotyping. However, interpopulation genetic distances showed no association with geographic distance between the population sites of origin, negating a simple isolation by distance model. Spatial autocorrelation of RAPD frequencies suggests that migration is not influential. Our present RAPD results are non-random and in agreement with the previously obtained allozyme patterns, although the genetic diversity values obtained with RAPDs are much higher than the allozyme values. Significant correlates of RAPD markers with various climatic and soil factors suggest that, as in the case of allozymes, natural selection causes adaptive RAPD ecogeographical differentiation. The results obtained suggest that RAPD markers are useful for the estimation of genetic diversity in wild material of T. dicoccoides and the identification of suitable parents for the development of mapping populations for the tagging of agronomically important traits derived from T. dicoccoides. Received: 13 July 1998 / Accepted: 13 August 1998     

Detection of interspecific and intraspecific variation in Panicum millets through random amplified polymorphic DNA

The potential use of random amplified polymorphic DNA (RAPD) was evaluated as a source of genetic markers for studying variation among four species of Panicum and within the crop species P. miliaceum and P. sumatrense. Polymorphism in RAPD markers was observed across and within species. The four species were distinct in RAPD patterns and were separated at low correlation values even with small samples involving single genotypes per species. Accessions of P. miliaceum were grouped according to geographical regions of origin. The study demonstrated that unlike isozyme and protein electrophoresis patterns, RAPD markers can be applied to studying genetic diversity, defining gene pools, and identifying cultivars for this group of millets.     

Development of Molecular Tools for Characterization and Genetic Diversity Analysis in Tunisian Fig (Ficus carica) Cultivars

Fig, Ficus carica L., is a useful genetic resource for commercial cultivation. In this study, RAPD (60), ISSR (48), RAMPO (63), and SSR (34) markers were compared to detect polymorphism and to establish genetic relationships among Tunisian fig tree cultivars. The statistical procedures conducted on the combined data show considerable genetic diversity, and the tested markers discriminated all fig genotypes studied. The identification key established on the basis of SSR permitted the unambiguous discrimination of cultivars and confirmed the reliability of SSR for fingerprinting fig genotypes. The study findings are discussed in relation to the establishment of a national reference collection that will aid in the conservation of Tunisian fig resources.     

DNA polymorphisms in grain sorghum (Sorghum bicolor (L.) Moench)

Molecular markers [random amplified polymorphic DNA (RAPD) and restriction fragment length polymorphism (RFLP)] were used to determine the frequency of DNA polymorphism in grain sorghum (Sorghum bicolor (L.) Moench). Twenty-nine oligonucleotide primers were employed for RAPDs, generating a total of 262 DNA fragments, of which 145 were polymorphic in at least one pairwise comparison between 36 genotypes. Individual primers differed significantly in their ability to detect genetic polymorphism in the species. The overall frequency of polymorphisms was low with a mean frequency of 0.117 polymorphisms per RAPD band being obtained from all pairwise comparisons between genotypes, with maximum and minimum values of 0.212 and 0.039, respectively. Results from phenetic analysis of bandsharing data were consistent with current sub-specific groupings of the species, with clusters of Durra, Zerazera, Caud-Nig, Caud-Kaura and Caffrorum being discernible. The results also indicated that individuals of a similar taxonomic grouping but different geographic origin may be genetically less identical than previously considered. Similar frequencies of polymorphism to that obtained with RAPDs were obtained with RFLPs. Results from these experiments indicated that a high level of genetic uniformity exists within S. bicolor.     

Genetic diversity of different Tunisian fig (Ficuscarica L.) collections revealed by RAPD fingerprints

The genetic diversity in Tunisian fig (Ficus carica L.) was studied using RAPD markers. Thirty-five fig cultivars originating from diverse geographical areas and belonging to three collections were analysed. Random decamer primers were screened to assess their ability to detect polymorphisms in this crop. Forty-four RAPD markers were revealed and used to survey the genetic diversity and to detect cases of mislabelling. As a result, considerable genetic diversity was detected among the studied F. carica accessions. The relationships among the 35 varieties were studied by cluster analysis. The dendrogram showed two main groups composed of cultivars with similar geographic origin. Moreover, the male accessions (caprifigs) were clustered indistinctively within the female ones, suggesting a narrow genetic diversity among these accessions. Our data proved that RAPD markers are useful for germplasm discrimination as well as for investigation of patterns of variation in fig. Since this designed procedure has permitted to establish a molecular database of the reference collections, the opportunity of this study is discussed in relation to the improvement and rational management of fig germplasm.     

Comparison of RAPD and RFLP genetic markers in determining genetic similarity among Brassica oleracea L. genotypes

Genetic similarity among 45 Brassica Oleracea genotypes was compared using two molecular markers, random amplified polymorphic DNA (RAPD) and restriction fragment length polymorphisms (RFLPs). The genotypes included 37 broccolis (var. italica), five cauliflowers (var. botrytis) and three cabbages (var. capitata) which represented a wide range of commercially-available germplasm, and included open-pollinated cultivars, commercial hybrids, and inbred parents of hybrid cultivars. Fifty-six polymorphic RFLP bands and 181 polymorphic RAPD bands were generated using 15 random cDNA probes and 62 10-mer primers, respectively. The objectives were to compare RFLP and RAPD markers with regard to their (1) sampling variance, (2) rank correlations of genetic distance among sub-samples, and (3) inheritance. A bootstrap procedure was used to generate 200 random samples of size n (n=2,3,5,... 55) independently from the RAPD and RFLP data sets. The coefficient of variance (CV) was estimated for each sample. Pooled regressions of the coefficient of variance on bootstrap sample size indicated that the rate of decrease in CV with increasing sample size was the same for RFLPs and RAPDs. The rank correlation between the Nei-Li genetic similarity values for all pairs of genotypes (990) based on RFLP and RAPD data was 0.745. Differences were observed between the RFLP and RAPD dendrograms of the 45 genotypes. Overlap in the distributions of rank correlations between independent sub-samples from the RAPD data set, compared to correlations between RFLP and RAPD sub-samples, suggest that observed differences in estimation of genetic similarity between RAPDs and RFLPs is largely due to sampling error rather than due to DNA-based differences in how RAPDs and RFLPs reveal polymorphisms. A crossing algorithm was used to generate hypothetical banding patterns of hybrids based on the genotypes of the parents. The results of this study indicate that RAPDs provide a level of resolution equivalent to RFLPs for detemination of the genetic relationships among genotypes.     

Inter- and intraspecific genetic variation inHippophae (Elaeagnaceae) investigated by RAPD markers

Genetic diversity has been investigated by the application of molecular markers in, for the first time, all the taxa recognised in recent treatises of the genusHippophae. RAPD (random amplified polymorphic DNA) analyses were conducted with 9 decamer primers, which together yielded 219 polymorphic markers. We found 16 fixed RAPD markers, i.e. markers that either occurred in all plants of a population or were absent from all plants. Several of these markers were useful for analysis of interspecific relationships, whereas others can be considered as taxon-specific markers. Clustering of taxa and populations in our neighbour-joining based dendrogram was in good agreement with some recently suggested taxonomic treatises ofHippophae. Amount and distribution of genetic variability varied considerably between species. Partitioning of molecular variance withinH. rhamnoides supported earlier findings that a considerable part of the total variance resides among subspecies (59.6%) Within-population variability also differed considerably. Percentage polymorphic RAPD loci and Lynch and Milligan within-population gene diversity estimates showed relatively high values for some species close to the geographic centre of origin in Central Asia, e.g.H. tibetana and the putatively hybridogenousH. goniocarpa. Spatial autocorrelation analyses performed on 12 populations ofH. rhamnoides revealed positive autocorrelation of allele frequencies when geographic distances ranged from 0 to 700 km, and no or negative autocorrelation at higher distances. At distances between 700 and 1900 km, we observed deviations from the expected values with strongly negative autocorrelation of allele frequencies. A corresponding relationship between geographic and genetic distances could not be found when the analysis instead was based on one population from each of 8 species.     

Genetic analysis of Spanish melon (<Emphasis Type="Italic">Cucumis melo</Emphasis> L.) germplasm using a standardized molecular-marker array and geographically diverse reference accessions

Genetic relationships among 125 Spanish melon (Cucumis melo L.) accessions from a Spanish germplasm collection were assessed using a standard molecular-marker array consisting of 34 random amplified polymorphic DNA (RAPD) markers bands (19 primers) and 72 reference accessions drawn from previous studies. The reference accession array consisted of a broad range [Japanese (19) Crete (17), African (15), and USA and Europe (US/EU, 21)] of horticultural groupings (Group Cantalupensis, Group Conomon, Group Inodorus, Group Flexuosus, and Group Chito), and of melon market classes (e.g., Charentais, U.S. Western and European Shipper types, Ogen, and Galia, Honeydew, and Casaba). Spanish melon accessions (largely Casaba, Group Inodorus) were genetically distinct from the reference accessions and other Group Inodorus melons of different origins. Most African accessions showed common genetic affinities, and grouped with the Group Chito and the Group Conomon accessions examined. Those accession groupings were distinct from all other accessions belonging to Group Cantalupensis, Flexuosus, and Inodorus accessions originating from Crete, Japan, Europe, and the U.S. Genetic diversity was highest in accessions of African origin and lowest in accessions of Spanish origin. Additional RAPD markers (49 primers, 141 bands) and 22 selected agronomic traits (quantitative and qualitative) were then used to assess the genetic diversity among Spanish accessions. While cluster analysis using fruit characteristics grouped accessions into cultivars, RAPD-based genetic-distance estimate did not provide consistent accession groupings either by cultivar or geographic origin. While the highest level of polymorphism was detected among melons originating from the central region of Spain, and in the Rochet cultivar, accessions from the Andalucía region and Green cultivars were comparatively less diverse. These results indicate that the Spanish melon accessions could be used to broaden the genetic base of local and foreign Casaba germplasm, to enhance the genetic diversity of U.S and European commercial melon germplasm, and to delineate collection strategies for acquisition of additional Spanish landraces.Communicated by C. MöllersMention of trade name, proprietary product, or specific equipment does not constitute a guarantee or warranty by the USDA and does not imply its approval to the exclusion of other products that may be suitable.     

Evaluation of the extent of genetic variability among Theobroma cacao accessions using RAPD and RFLP markers

 Random amplified polymorphic DNA (RAPD) and restriction fragment length polymorphism (RFLP) markers were used to evaluate genetic relationships within the Theobroma cacao species and to assess the organization of its genetic diversity. Genetic variability was estimated with 18 primers and 43 RFLP probes on 155 cocoa trees belonging to different morphological groups and coming from various geographic origins. The majority of the RFLP probes issued from low-copy DNA sequences. On the basis of on the genetic distance matrices, the two molecular methods gave related estimates of the genetic relationship between genotypes. Although an influence of cocoa morphological groups and geographical origins of trees was observed, a lack of gene differentiation characterized the T. cacao accessions studied. The continuous RFLP variability observed within the species may reflect the hybridization and introgressions between trees of different origins. Nevertheless, the Nacional type was detected to be genetically specific and different from well-known types such as Forastero, Criollo and Trinitario. Some of those genotypes were characterized by a low heterozygosity rate and may constitute the original Nacional pool. These results also provide information for the constitution of a cocoa tree core collection. Received: 10 June 1996/Accepted: 11 October 1996     

Genetic variations among mulberry genotypes (Morus alba) as revealed by Random Amplified Polymorphic DNA (RAPD) markers

Turkey is one of the most important mulberry fruit producers in the world. In particular, in Eastern and Inner part of Turkey, mulberry fruits are processed into several products such as `Mulberry Pekmez', `Mulberry Pestil', `Mulberry Kome' etc. Therefore, mulberry fruits give higher economic returns thus have greater employment potentials in Turkey. In order to improve the yield and fruit quality through breeding, the genetic variations and relationships among 15 selected white mulberry genotypes (Morus alba L.) were evaluated using Random Amplified Polymorphic DNA (RAPD). A total of 101 DNA markers were generated by 16 random primers, with an average of 6.3 easily detectable markers per primer. Several RAPD markers showed unique patterns of mean frequency that differed among the white mulberry genotypes. The distance matrix showed that the highest genetic distance (0.902) was between EMS13 and EMS8 and the least (0.413) was between EMS12 and EMS15. According to the results, RAPD analysis can be used for the characterization and grouping of mulberry genotypes. The genetically divergent genotypes identified from this study would be of much use in the future breeding program.     

Genetic relationships of Japanese and Indian mulberry (Morus spp.) genotypes revealed by DNA fingerprinting

Mulberry (Morus spp.), a deciduous tree, originated at the foothills of the Himalayas and is used in sericulture for its leaf to feed the silkworm Bombyx mori L. Species differentiation among the genotypes of the genus Morus has never been out of debate as inter-specific hybridization events are often fertile. In the present study attempts were made to elucidate the genetic relationships among 18 mulberry genotypes collected from India and Japan using 15 Inter Simple Sequence Repeat (ISSR) and 15 Random Amplified Polymorphic DNA (RAPD) primers. The ISSR primers generated 81.13% polymorphism while the RAPDs generated 71.78% polymorphism. The polymorphic index of the primers identified UBC-812, UBC-826, UBC827, UBC-881, OPA-01, OPA-02, OPA-04 and OPH-17 as informative primers in mulberry. The genetic similarity coefficients and the dendrograms showed considerable genetic similarity among the genotypes. However, using the DNA markers, these genotypes were discriminated into two major groups in accordance with their geographic origin and species status. Distribution of the genotypes on a two-dimensional figure on the basis of the ALSCAL algorithm using Euclidean distance further confirmed the genetic divergence between these two groups. From the study it can be concluded that though morphologically Japanese and Indian mulberry genotypes show little divergence, genetic analysis using DNA markers could unravel significant genetic variation between these two groups. Similarly, while the species status of Japanese mulberry genotypes agrees with the genetic analysis, the same does not apply to Indian genotypes, in agreement with many earlier reports. The information generated in this study is of much use for taxonomical grouping and also for utilization in breeding and conservation programs.     

Microsatellite DNA and RAPD fingerprinting,identification and genetic relationships of hybrid poplar (<Emphasis Type="Italic">Populus x canadensis</Emphasis>) cultivars

Microsatellite DNA markers of ten SSR loci and 248 RAPD loci (resolved by 26 RAPD primers) were used for DNA fingerprinting and differentiation of 17 widely grown Populus x canadensis syn. Populus x euramericana (interspecific Populus deltoides x Populus nigra hybrids) cultivars ("Baden 431", "Blanc du Poitou", "Canada Blanc", "Dorskamp 925", "Eugenei", "Gelrica", "Grandis", "Heidemij", "I-55/56", "I-132/56", "I-214", "Jacometti", "Ostia", "Regenerata", "Robusta", "Steckby" and "Zurich 03/3"), and determination of their genetic interrelationships. Informativeness of microsatellite and RAPD markers was also evaluated in comparison with allozyme markers for clone/cultivar identification in P. x canadensis. High microsatellite DNA and RAPD genetic diversity was observed in the sampled cultivars. All of the 17 P. x canadensis cultivars could be differentiated by their multilocus genotypes at four SSR loci, and were heterozygous for their parental species-specific alleles at the PTR6 SSR locus. Except for "Canada Blanc" and "Ostia", which had identical RAPD patterns, all cultivars could also be differentiated by RAPD fingerprints produced by each of the two RAPD primers, OPA07 and OPB15. For microsatellites, the mean number of alleles, polymorphic information content, observed heterozygosity, observed number of genotypes and the number of cultivars with unique genotypes per locus was 5.2, 0.64, 0.67, 5.7 and 2.2, respectively. For RAPD markers, the number of haplotypes per locus, and the number of cultivars with unique RAPD profiles per locus were 1.06 and 0.72, respectively. Overall, microsatellite DNA markers were the most informative for DNA fingerprinting of P. x canadensis cultivars. On the per locus basis, microsatellites were about six-times more informative than RAPD markers and about nine-times more informative than allozyme markers. However, on the per primer basis, RAPD markers were more informative. The UPGMA cluster plots separated the 17 cultivars into two major groups based on their microsatellite genotypic similarities, and into three major groups based on their RAPD fragment similarities. Both the microsatellite and RAPD data suggest that the cultivars "Baden 431", "Heidemij", "Robusta" and "Steckby" are genetically closely related. The inter-cultivar genetic relationships from microsatellite DNA and RAPD markers were consistent with those observed from allozyme markers, and were in general agreement with their speculated origin. Microsatellite DNA and RAPD markers could be used for clone and cultivar identification, varietal control and registration, and stock handling in P. x canadensis.     

Molecular characterization of Ephedra species found in Pakistan

Ephedra, also known as "ma huang", is a dioecious, drought- and frost-resistant, perennial, evergreen shrub with compelling medicinal value. The genus is represented by 42 species around the world, 9 of which were provisionally reported from Pakistan. Species of the genus have a controversial taxonomy due to their overlapping morphological features. Conventional tools alone are not sufficient for characterizing the species. The objective of present study was to assess the genetic variability present in different biotypes of Ephedra growing in Pakistan using molecular markers. A total of six genotypes collected from diverse geographic zones of Pakistan were used. The DNA of all genotypes was amplified using nine randomly amplified polymorphic DNA (RAPD) primers to study genetic variability at the molecular level. The dissimilarity coefficient matrix based on the data of 9 RAPD primers was used to construct a dendrogram which was then used to group the genotypes in clusters. Based on the dendrogram and dissimilarity coefficient matrix, the RAPD markers used here revealed a moderate to high level of genetic polymorphism (6 to 49%) among the genotypes. It was found that the collection of genotype accessions from Swat Valley in northwestern Pakistan was most distantly related to the other five collections. More molecular markers including functional genes and ribosomal spacer regions are suggested to find a better estimate of the genetic diversity present in Ephedra growing in Pakistan. The information provided here is useful for identifying valuable Ephedra variants which will be used for medicinal purposes and earning foreign currency.     

Infraspecific differentiation of garlic (Allium sativum L.) by isozyme and RAPD markers

Garlic (Allium sativum L.) is a sterile species of considerable variability with respect to morphological and physiological features. The crop presumably originated in West to Middle Asia from its progenitor A. longicuspis Regel and was transported from there to the Mediterranean and other areas of cultivation. In order to clarify older classification schemes, often based on small or biased collections, we used isozyme and RAPD markers to analyze and structure a collection of 300 accessions, many of which were gathered in Middle Asia close to the assumed center of origin. All of the accessions were first investigated with isozymes, and 48 were selected for a RAPD analysis. The resulting molecular markers were used to construct neighbor-joining dendrograms to group the accessions and to indicate the genetic distances between them. Based on the dendrograms and in conjunction with some morphological features, we propose an infraspecific classification of garlic with four major groups. In agreement with the results of other workers, A. longicuspis lies within the range of the species A. sativum. Numerous forms with varying degrees of domestication are part of our longicuspis group, from which presumably the more derived cultivar groups originated. The origin and spreading of the crop are discussed with respect to the geographical distribution and the genetic distances of the accessions.     

Molecular phylogeny of date palm (Phoenix dactylifera L.) cultivars from Saudi Arabia by DNA fingerprinting

Genetic diversity among 13 different cultivars of date palm (Phoenix dactylifera L.) of Saudi Arabia was studied using random amplified polymorphic DNA (RAPD) markers. The screening of 140 RAPD primers allowed selection of 37 primers which revealed polymorphism, and the results were reproducible. All 13 genotypes were distinguishable by their unique banding patterns produced by 37 selected primers. Cluster analysis by the unweighted paired group method of arithmetic mean (UPGMA) showed two main clusters. Cluster A consisted of five cultivars (Shehel, Om-Kobar, Ajwa, Om-Hammam and Bareem) with 0.59–0.89 Nei and Li's coefficient in the similarity matrix. Cluster B consisted of seven cultivars (Rabeeha, Shishi, Nabtet Saif, Sugai, Sukkary Asfar, Sukkary Hamra and Nabtet Sultan) with a 0.66–0.85 Nei and Li's similarity range. Om-Hammam and Bareem were the two most closely related cultivars among the 13 cultivars with the highest value in the similarity matrix for Nei and Li's coefficient (0.89). Ajwa was closely related with Om-Hammam and Bareem with the second highest value in the similarity matrix (0.86). Sukkary Hamra and Nabtet Sultan were also closely related, with the third highest value in the similarity matrix (0.85). The cultivar Barny did not belong to any of the cluster groups. It was 34% genetically similar to the rest of the 12 cultivars. The average similarity among the 13 cultivars was more than 50%. As expected, most of the cultivars have a narrow genetic base. The results of the analysis can be used for the selection of possible parents to generate a mapping population. The variation detected among the closely related genotypes indicates the efficiency of RAPD markers over the morphological and isozyme markers for the identification and construction of genetic linkage maps.Communicated by H.F. Linskens     

RAPD analysis of Fusarium Isolates Causing “Mango Malformation” Disease in Pakistan

Mango Malformation (MM) disease is a major constraint to mango production. A total of 20 Fusarium isolates from MM-affected mango plants were collected from 14 locations in Pakistan and assessed for genetic diversity using the random amplified polymorphic DNA (RAPD) technique. A total of 393 fragments were amplified after screening with 50 random primers. The amplifications with 45 primers identified scoreable polymorphisms among the isolates. A genetic similarity matrix based on Nei and Li’s index determined coefficients ranging from 46.46% to 92.51%. These coefficients were used to construct a dendrogram using the UPGMA algorithm. The isolates grouped into two main clusters, comprising 13 and 7 isolates respectively, at a genetic relatedness of 52%. Within the clusters, Fusarium isolates were not necessarily related either by geographic origin or by the mango cultivar from which they were isolated. RAPD proved a reproducible and tractable means of differentiating Fusarium isolates. These findings also suggest that some infections originate not from adjacent plants within an orchard but from geographically distant areas; indicating that most probably infection occurs in nurseries prior to plants being transported around the country for subsequent cultivation, and that improved plant hygiene could significantly curb MM infection and spread.     

Genetic Diversity of Selected Iranian Quinces Using SSRs from Apples and Pears

An Iranian National Quince collection containing 40 quince genotypes, originating from six distinct geographic areas, was screened using 15 SSR markers developed originally for apple and pear genomes. Overall, 13 markers exhibited polymorphism, with an average of 5.36 putative alleles per locus and a mean PIC value of 0.76. An UPGMA analysis divided the quince genotypes into five major clusters. The same results were obtained when the principal coordinates were plotted. The assignment test successfully allocated 83% of individuals into their place of origin. These results agree somewhat with the geographic origin of the quince accessions, and we conclude that geographic isolation leads to considerable genetic differentiation among Iranian quince collections. A significant ratio of transferability with a mean of 87.86% was measured, and we deduced that STMS markers derived from pear and apple have enough potential to detect polymorphism and differentiation in quince.     

Analysis of the genetic diversity and relationships among and within species of Hippophae (Elaeagnaceae) based on RAPD markers

RAPD markers were used to assess the genetic diversity and inter- and intra-specific relationships of the genus Hippophae L. and to study the correlation between genetic distances and geographic distances among populations of H. rhamnoides ssp. sinensis. The results analyzed by the percentage of polymorphic loci and Shannon information index indicated that a high level of genetic diversity existed both among and within species of the genus Hippophae. In the UPGMA dendrogram, the species or subspecies were clustered into two main groups but not strictly grouped according to sect. Hippophae and sect. Gyantsensis Lian. The multiple regression analysis and Mantel test both indicated a significant correlation between genetic distance and altitude distance among populations of H. rhamnoides ssp. sinensis, and the cluster analysis suggested that the genetic variation among populations of H. rhamnoides ssp. sinensis was linked to their monophyletic origin. Moreover, some degree of genetic differentiation was found among samples collected at different times.     

Use of molecular markers and flow cytometry to preserve ancient Annurca apple germplasm

The old Annurca apple cultivar (Malus domestica), particularly appreciated for its peculiar flavor and crispy flesh, was studied in order to preserve its ancient germplasm. Twelve clones of Annurca were analyzed using random amplified polymorphic DNA (RAPD) and simple-sequence repeat (SSR) markers. Two out of 30 RAPD primers and nine out of ten SSR primers were able to discriminate all the clones analyzed. Data were confirmed by measuring DNA content using flow cytometry. The results provide a good procedure to improve germplasm field management, in order to removing redundant material in the Annurca collection. This represents an efficient way to create a data bank in order to preserve the genetic variability of the Annurca cultivar. M. Iannaccone, D. Palumbo and I. Ventimiglia contributed equally to this work