جستجوی مقالات مرتبط با کلیدواژه "marker" در نشریات گروه "بیوتکنولوژی و ژنتیک گیاهی"

Increasing grain yield and improving the quality of bread are among the most important goals of wheat breeding programs in Iran. Understanding the genetic control of traits and finding molecular or morphological markers associated with them are also prerequisites for any genetic engineering program. In this study, 100 progenies of a 10 × 10 diallel cross were used to analyse the genetics of grain yield and bakery values using STS markers associated with HMWG subunits. This research was carried out during 2018 and 2019 cropping season at Gorgan University of Agricultural Sciences and Natural Resources experimental fields. In the first year, 10 wheat cultivars, including Gonbad, Morvarid, Kalate, Ehsan, Sirvan, Baharan, Chamran2, Shush, Mehrgan and Brat collected from different geographical regions of Iran were planted and crossed in the field. In the second year, the parents and crosses were planted in the form of a randomized complete block design with three replications. The grain yield, number of spikes per plant, number of seeds per spike, seed weight, days to emergence and plant height were recorded. The results of this study indicated significant genetic differences between the parents. Narrow-sense heritability analysis revealed that the crossing of cultivars is the best breeding method to enhance seed yield, number of spikes per plant and days to emergence. Also, to improve the number of seeds per spike, seed weight and plant height, classical breeding methods may offer higher efficiency. Marvarid and Gonbad were ranked 1st and 2nd, respectively with respect to general combining abilities for grain yield, attributed to their positive and significant general combining ability effects. The highest specific combining ability was observed for Ehsan×Gonbad, Marvarid×Chamran 2 and Shush×Sirvan crosses. The results of molecular markers analysis showed that the STS markers were able to identify the difference in the baking value of cultivars. The quality score of the cultivars ranged 6 and 10 and to this end, Kalate and Brat were the top cultivars. Therefore, due to superiority in terms of both quantity and quality for yield, these cultivars can be used as parents with desirable genes for future breeding programs. Overall, the STS markers employed in this study proved to be valuable markers for enhancing the genetic background of bread wheat, particularly when employing marker-assisted selection for bakery value.

Fenugreek (Trigonella foenum-graecum L.) as an important aromatic and medicinal plant is a rich source of the Diosgenin and Trigonelline. Genetic diversity analysis using reliable methods provides useful information for the crop breeding programs and conservation of genetic resource. In the present study, 40 Fenugreek genotypes were evaluated for genotypic diversity using two gene-targeted markers. Seven SCoT and ten CBDP primers amplified 78 and 93 fragments in which 65 and 78 were polymorphic, respectively. The average of polymorphism information content (PIC) for SCoT and CBDP Primers were 0.37 and 0.29 respectively, that showed a higher resolving power of SCoTs than CBDPs. The dendrogram generated using the UPGMA algorithm based on Dice distance coefficient, classified all 40 investigated samples into four main groups. Furthermore, these results were confirmed by principal coordinate analysis (PCoA). Analysis of molecular variance (AMOVA) showed a higher distribution of genetic diversity within populations (66%), than between them (34%). Among all five investigated populations, the highest values of diversity indexes such as number of effective alleles (1.54), Shannon’s index (0.46) and Nei’s gene diversity (0.31) were estimated for population IV indicating the higher variation within this population than others. These results showed a high amounts of genetic variation among tested genotypes, which can be used in breeding programs. Moreover, the results revealed that these two gene-targeted markers are suitable and reliable techniques for DNA fingerprinting and genetic diversity investigations.

Grape is one of the most important horticultural products in the world and in Iran and has a high genetic diversity. Determining the level of genetic diversity is the first step in plant breeding programs. Knowledge of genetic diversity, in addition to providing information on evolutionary and phylogenetic relationships, genetic mapping, ecological and environmental adaptations, and ultimately selecting the right parents for breeding programs, will reduce the time and cost of breeding projects. This study was performed to investigate the genetic diversity of 69 cultivars and promising genotypes of Russian grapevines with three Iranian commercial grapevine cultivars using 15 microsatellite markers (ISSR). Polymerase chain reaction (PCR) samples were electrophoresed in 1.3% agarose gel. Cluster analysis with the UPGMA method was used based on the Jaccard coefficient after assigning one and zero to the presence or absence of a band in each primer for each genotype. The highest percentage of polymorphisms (100%) was related to UBC-823, UBC-825, UBC-841, UBC-846, UBC-855, and UBC-873 primers, and the lowest (66.7%) was related to UBC-817 primer. The highest and lowest levels of the polymorphic content index were observed in UBC-825 (0.487) and UBC-856 (0.216) primers, respectively. The highest and lowest levels of marker index were 2.718 and 0.904 related to UBC-889 and UBC-817 primers, respectively. The highest and lowest values of the effective multiplex ratio index were 7 and 1.33 for UBC-841 and UBC-817 primers, respectively. The highest and lowest resolving power were 8.11 and 2 for UBC-877 and UBC-841 primers, respectively. The UBC-815 and UBC-834 primers had no clear and concise bands. Overall, 73 bands were obtained from the 13 primers of the ISSR DNA marker which 64 bands were polymorphic and the total polymorphism was 88.1%. The highest and lowest numbers of bands were eight and two bands for UBC-826 and UBC-817 primers, respectively. The cluster analysis was performed by the UPGMA method based on Jaccard's coefficient of similarity, which led to the classification of 72 grape varieties with a similarity value of 0.12 to 0.89 in seven different groups. In the present study, high diversity was observed among the studied grapevine cultivars. This indicates the different geographical origins of the cultivars and genotypes under study.

Persian black cumin is one of the most important endemic plants to Iran. Its seed is used in the daily diet of Iranians and also has medicinal properties and aromatic compounds. Unfortunately, there is little information about its genome and molecular markers. In this study, the transcriptome of Iranian black cumin was sequenced in the granulation stage and after extracting the microsatellites (SSR markers) related to this growth stage, their interpretation was done. After RNA extraction, the inflorescences and stems were sequenced. Sequencing depth and length were 6 GB and 150 bp pair-end, respectively. Sequencing data were analyzed using different softwares. De-novo assembly of Persian black cumin was performed by Trinity software. Microsatellite markers were extracted using MISA software. Finally, the functional interpretation of the microsatellite-containing sequences was performed by the WEGO database. The GC content of different samples was 47 to 50%. 8389 microsatellite markers were obtained from 45146 unigenes. At least 11% of unigenes contained microsatellites. A/T and AG/CT nucleotides had the highest percentage of microsatellite markers. Among the three nucleotide repeats, ATC/ATG and AAG/CTT had the highest frequency of microsatellites. The results of functional interpretation showed that unigenes containing microsatellite markers cover a wide range of biological activities of Persian black cumin and the genes involved in seed development and growth have a high level of expression. This study is the first report of microsatellite markers of Persian black cumin. The results of the present study can be useful in finding different markers for breeding programs and developing cultivars with different goals.

Durum wheat (Triticum turgidum) with an average annual production of 40 million tons, is the tenth most important and common crop grown worldwide. The aim of this study was to analysis the genetic diversity and population structure of durum wheat genotypes for knowledge and apply in future genomic studies using SilicoDArT markers generated by DarTseq.

The DNA of 94 durum wheat genotypes were extracted by CTAB method from fresh leaves. The quality and quantity of extracted DNA were measured using spectrophotometer and adjusted to 50 ng / μl. The DNA samples were processed at Diversity Array Technology Pty, Ltd, Australia (https://www.diversityarrays.com) for DArTseq analyses using genotyping by sequencing Platform. Genetic diversity and population structure analysis were performed on the remaining 7882 markers using: Power Markerv.3.25, DARwinver 5.0, STRUCTURE2.1., GenAlexv. 6.41 and Rv3.2.3 software.

The amount of polymorphic information content (PIC) of SilicoDArT markers ranged from 0.023 to 0.499 with an average of 0.38. The mean reproducibility and call rate of sequences in all linkage groups were above 0.98 and 0.92, respectively. The number of mapped SilicoDArT markers varied from 300 markers in the linkage group (Chr1A) to 853 markers in the linkage group (Chr7B). Chromosome size covered by SilicoDArT markers ranged from 829200 kbp in the linkage group (Chr3B) to 589293.786 kbp in the linkage group (Chr1A). The results of cluster analysis by Neighbor-Joining (NJ) method, population structure and discriminant analysis of principal components were highly consistent with each other and clearly divided the studied genotypes into four distinct groups. Genetic diversity among populations was primarily within the population (76.36 vs. 23.64%).

The relatively high number of subpopulations and the presence of high genetic diversity among and within populations were the characteristics of studied durum wheat genotypes in this study. Therefore, considering the loss of 84% genetic diversity of durum wheat during the early domestication processes, these populations can be used as a valuable resource in basic and applied research in breeding projects.

In order to identify the QTLs controlling the morphologic traits of bread wheat, 148 recombinant inbred lines of spring wheat derived from American Yecora Rojo (early maturity and dwarf as the male parent) and No.49 genotype from Sistan Baluchestan (late maturity and tall as the female parent) were studied with the parents. The studied traits included peduncle length, spike length, awn length, flag leaf length, the number of spikes, spike weight, and the number of grains in spike. In this study, linkage map was used based on 202 markers (177 SSR markers and 51 Retro transposon Markers). The map length was about 691.36 cM with the average distance of 3.42 cM in every marker pair and covered 21 chromosomes in bread wheat. QTL analysis was done based on composite interval mapping (CIM) method, and additive effects were estimated for the identified QTLs. The results of QTL analysis showed that one QTL was detected on chromosomes 7B, 5A, 3A, 4A, 3A and 3A respectively for plant height, peduncle length, spike length, awn length, flag leaf length, the number of seed per spikes; two QTL was detected on chromosomes 3A and 2D for the number of spike and seed wieght per spike; and three QTLs were detected and mapped on chromosomes 3A, 4A, and 3A for spike weight. Among the detected QTLs, QSNS3A had the highest additive effect. For spike length, spike weight, the number of grains in spike, and seed weight per spike. The negative additive effect of the mapped QTLs indicate the optimal allele inheritance to crosses in this position of No.49 parent. The phenotypic variance explained by these QTLs varied from 4.93 to 13.63. In this study, the number of QTLs found for spike traits was so limited; it can be due to the large number of small-effect QTLs, mutual effects, and environmental effects.

This study aimed to investigate the genetic diversity of different genotypes of this valuable medicinal plant under the same culture condition which can be used as an introduction to domestication, germplasm conservation, and possible cross in the future.

In this study, after preparing 20 different genotypes from all over Iran, they were cultivated in complete randomized blocks design with three replications under the same condition. After extraction of DNA, the survey of genetic diversity using 12 ISSR markers from 15 markers was conducted by polymerase chain reaction (PCR). The essential oil for each genotype was extracted by water distillation. The dry yield based on gr/m2 and essential oil content (w/w, based on dry weight) were measured. Furthermore, the correlation of molecular markers with dry yield and essential oil content from each genotype was determined using stepwise regression. 

The mean percentage of polymorphism determined in all the genotypes was 91.97. The number of polymorphic bands for each primer varied from 5 to 9 and a total of 89 replicate bands were scored, of which 82 bands showed polymorphism. The average content of primer information polymorphism (PIC) was estimated to be 0.31 and the IS1 primer showed the highest PIC (0.46). The Ni and Shannon indices for IS1 primers were 0.43 and 0.61, respectively. Cluster analysis using the Jaccard similarity coefficient and UPGMA algorithm divided the studied genotypes into four groups. The highest genetic distance was observed between Khuzestan and Qazvin genotypes with a coefficient of 0.39 and the lowest between Kerman-2 and Kerman-4 genotypes with a similarity coefficient of 0.77. Stepwise regression showed that the IS10 primer has a coefficient of 0.70 with the essential oil percentage and dry matter yield.

The results of this study showed that ISSR markers can be effectively used to study the genetic diversity of wild mint genotypes and will provide the possibility of breeding. So that, IS1 and IS10 primers were introduced as the best markers. Also, Khuzestan and Qazvin genotypes had the highest genetic distance.

Genetic diversity is of great importance for breeding programs. In order to study the genetic diversity of 102 different rice genotypes based on seedling traits and molecular experiments, an experiment was conducted in a Completely Randomized Design with three replications. The studied traits including Plumule length, radicle length, length of the largest leaf, width of the largest leaf, number of root, fresh shoot weight, fresh weight of root and root volume, and dry weight of shoot, dry weight of root were measured. The average of the Polymorphic of information content (PIC) was estimated to be 0.2716, indicating RM1029 with the of least 0.175 and the RM216 with the highest of 0.435 (PIC). The results of Association analysis between microsatellite marker and seeding traits at normal condition indicated that the RM60B allele for root length, RM127A allele for root, RM231G allele for the fresh weight of the stem explained high percentage of variations. In saline condition, RM129H allele for stem length trait, RM12091 B allele for root attribute, RM263G allele for stem fresh weight, RM127C allele for width of largest leaf explained high percentage of phenotypic variations and were identified as important markers. The results of this experiment can be used in breeding programs.

In order to mapping additive and epistatic QTL and their interaction with environment for traits related to spike characteristics using a RILs population of wheat, comprising 148 recombinant inbred lines derived from a cross between two winter wheat cultivars, ‘YecoraRojo’ and ‘No. 49’, was evaluated in two locations in Iran (Miandoab and Mahabad) during 2014-2016. A linkage map including 177 microsatellite and 51 retrotransposon markers was used in this study. Quantitative trait loci (QTL) were determined using QTL Network 2.0 software based on the CIM and mixed-linear method. In the present study, the highest broad (58.31%) and narrow-sense (29.15%) heritability was measured for spikelet number per spike and the lowest broad (51.28%) and narrow-sense (25.64%) heritability was detected for spike length. Results of QTL analysis showed that in normal condition, one QTL (R2A= 1.54%), one QTL×E (R2AE= 4.40%), 2 additive × additive epistatic effects (R2AA= 0.44- 0.4%) and 6 QTL × QTL×E interactions (R2AAE= 8.24-9.7%) were significant. In water deficit condition, 1 additive × additive interactions (R2AA= 4%) and 3 QTL × QTL × E interactions (R2AAE= 6.98%) were identified. In average of two conditions, two QTL (R2A= 0.78%), 1 QTL×E (R2AE= 5.15%), 10 additive × additive epistatic effects (R2AA= 0.02-7.9%) and 14 QTL × QTL × E interactions (R2AAE= 0.86-8.92%), were significant which can be due to the high number of QTLs with low effects and also environmental effects.

Lentil (Lens culinaris) is one of the important grain legumes in feeding (as protein-reach food) and industry (such as biopolymer industry) and the problem of lower yield of this plant in Iran rather than average global yield is affected by exposure of plant to environmental stresses especially drought. Identification of molecular markers that closely linked to drought resistant genes help to implementation of breeding programs aimed at the production of drought tolerant plants. The gol of this study was identification of EST-SSR markers which closely linked to the genes involved in drought resistance and use of these information in identification of drought resistant genotypes in breeding programs. PEG was used for stress treatment, and after conduction of treatments, leaf samples were collected. Total RNA was extracted and cDNA libraries were sequenced. Results showed that 10546 (16%) of uni-genes contained at least one EST-SSR and about 27.5% of these sequences were annotated. Among different SSR motif-classes, tri-nucleotide repeats (46.03%) were the most abundant followed by mono-nucleotide repeats (37.25%) and di-nucleotide repeats (15.18%). The results of the functional annotation of these sequences, showed that the highest number of EST-SSRs were belonged to subgroups of binding (872), catalytic activity (806), metabolic processes (755), and cell components (651), respectively.The results showed that genes associated with these markers, involved in important biological functions and are an appropriate tool for study the genes involved in tolerance to stresses including drought stress.

The genus Thymus L. is one of the largest genera of the Lamiaceae family and aromatic plants. Plants of these genera have commercial value due to their essential oils. Thymus eriocalyx is one of the species that is exclusively on the Iranian plateau. In order to investigate the molecular characteristics of Thymus eriocalyx populations in Iran, 10 habitats were selected in Lorestan, Markazi, Hamedan, Kermanshah and Kurdistan provinces (using the DSS method) (50 plant samples). Also, 15 primers with 10 N lengths selected. The molecular data, based on RAPD experiments, divided the populations into five distinct groups. Primers used in this experiment produced 71 bands, which showed 68 polymorphic bands. OPA-05, OPA-17, OPD03 and OPE-20 primers with the highest polymorphism and marker index had excellent ability to study genetic variation in studied species. P2 and P7 populations had the maximum effective allele and p9 population had the minimum value. The highest and lowest mean of expected heterozygosity belonged to P2 and P9 populations, respectively. The highest genetic similarity was observed between P2 and P3 genotypes and the lowest genetic similarity between P2 and P10. The results of analysis of variance (AMOVA) showed that the variation within the populations of these species (68%) is greater than the diversity among populations (32%), which this fact prove the importance of single plant selection and paying attention to individual in Thymus breeding programs.

Several reports were published in regard to the comparison of the efficiency of different molecular markers in genetic diversity studies for estimating genetic parameters. Most researches have been conducted out in different plant genomes and in different breeding programs, but there isn`t any report on comparing the efficiency of SSR and RAPD markers in marker-assisted selection (MAS) programs in rice genome. In this line, a research was conducted out to compare the two marker systems for estimating some genetic parameters in advanced backcross lines in rice. One hundred SSR primer pairs and 20 RAPD primers were used for fingerprinting of the studied genotypes. Polymorphism of RAPD markers was higher than SSR markers, while polymorphism information content (PIC) of SSR markers was more than 2 fold relative to RAPD markers. A weak correlation was observed between the two systems for estimating genetic similarity of progenies to recurrent parent. Also, results showed that increasing the number of RAPD markers didn`t cause any increase in estimation precision. The results of this research suggested the use of SSR markers in selection programs.

Wild plant species are considered as one of the most important sources for transferring of genes of valuable characteristics such as adaptability and resistance to diseases and pests into their cultivated relatives. In this study, ecotypes of wild species Carthamus lanatus were collected from eight different regions over the Golestan province and were evaluated by ISSR markers. Out of 24 tested markers, nine of them showed a 26.04% polymorphism, that marker ISSR 8 outputted better performance than others. Cluster analysis was classified the ecotypes into three separate groups. Ecotypes Bandartorkman was placed in first cluster and ecotype of intermediated of Bandartorkman –Aqqalla was located in second cluster and other ecotypes were in the third. Based on the Nei's genetic distances, ecotype of Ashuradeh island had the most distance from others and ecotypes Inchehbroon and Gomishan was the nearest. Also, primer 4 at locus 850 bp and primer 1 at locus 900 bp for samples collected from Ashoradeh island and primer 1 at locus 1025 bp for samples of ecotype Inchehbroon produced specific bands. Correct separation of ecotypes according to their geographic origin, confirmed efficiency of the microsatellite primer and also certified genomic differences between the 8 studied C. lanatus ecotypes. In general, the results showed that, C. lanatus ecotypes grown in Golestan province had considerable genetic variation, and also geographic distance has been a major factor for creation and preservation of genetic variability between these ecotypes.

Freezing tolerance is a major component of winter hardiness and the ability of plant to survive subfreezing temperatures. Recent advances of cloned genes and molecular markers in barley provide molecular breeders with the means to develop new and simple PCR-based molecular markers which can be used to select frost-tolerant genotypes quickly without stress simulation. In this paper، five molecular markers associated with two frost tolerance and vernalization QTLs (Vrn-H1/Fr-H1، Fr-H2 and Vrn-H2) were tested in 24 barley genotypes consisting of winter، facultative and spring habit types. Genotypes were characterized in terms of frost tolerance under artificial freezing test at -12°C. The marker HvBM5A related to Vrn-H1/Fr-H1، resulted to be the best predictor for assisted selection within this germplasm، because there is a highly significant difference in maximum quantum yield of the PSII photochemistry (Fv/Fm) and electrolyte leakage of organized groups in this marker. Also HvCBF3 marker was more associated than HvCBF14 at Fr-H2 with the frost tolerance. The evaluation of Fv/Fm showed that frost stress the photochemical efficiency of photosystem II to decline significantly that generally، this reduction in resistant genotypes (winter and intermediate growth types) was less than susceptible (spring habit). Furthermore frost stress causes serious damages on plants by injuring the cell membrane that investigation on this collection showed significant difference between mean of this trait in susceptible genotypes (spring type) 0. 381 and mean of cold tolerant genotypes (winter and facultative growth habit types) 0. 174.

Drought stress is a major constraint for barley production and yield stability in rainfed ecosystems. An advanced backcross breeding strategy was used to identify quantitative trait loci (QTLs) associated with yield and yield components in a BC3 population derived from an interspecific cross between six-rowed spring barley (H. vulgare) ‘Azhul’ and wild barley (H. spontaneum) line ‘Spontaneum I’، under drought stress. The linkage map constructed by 170 SSR molecular markers covered a total length of about 1008. 7 cM. For ten agronomical characteristics، 27 QTLs were determined. The phenotypic variation explained by individual QTLs ranged from 5. 7% to 34. 8% and the LOD scores ranged between 3 and 12. 4. A total of 12 new QTLs were identified، where at ten QTLs the exotic introgression caused an improved trait performance، under drought stress. Four QTLs contributed by ‘Spontaneum I’ on chromosomes 1H، 2H، 3H and 7H were found to significantly increase chlorophyll content، days to maturity، flag leaf length and number of tillers per spike، respectively. In conclusion، the results of this study showed that Hordeum spontaneum، the wild progenitor of barley، is a potential source of useful genetic variation for barley breeding programs.

In this study flowering time and some morphological traits were evaluated during two years in a F1 almond progeny of seventy two seedlings from the cross between ‘Tuono’)intermediate flowering (and ‘Shahrood-12’) late flowering(cultivars. Modified-bulk segregant analysis with the application of the 155 RAPD primers، spanning the whole almond genome were used to identify molecular markers linked to flowering time in several selected descendants from the studied almond progeny. Results showed a quantitative inheritance of this trait in the progeny and then to all 72 progenies. The seedlings evaluated showed a wide range of flowering time between both progenitors and some of these descendants were earlier than the intermediate flowering progenitor ‘Tuono’. The results showed that BA-17600،1000، BC-05320، BC-06800، BC-141750، BC-17600، BC-20250، OPC-05850 and OPC-09700 markers were linked to late blooming and BA-04720،BB-10630،BC-092000،BD-12510andOPC-12350 were linked to early blooming time. After construction of the genetic map of population، QTL analysis was performed for flowering time. The results showed that BA-17 primer had 4 cM distance from one of the late flowering time loci. Also،the OPC-09 and BA-04 primers were located at 2 and 3 cM distances from one of the genes controlling early and late flowering time، respectively. Identification of genetic markers linked to blooming time in almond are very important، because utilization of these markers will help the indirect selection of genotypes for desirable bloom time in early generation to saving time and effort. According to the obtained results، with the development of these markers، the strategies of marker assisted selection can be used in breeding programs of almond، apricot، peach and other Prunus species.

In this study, an F2:3 population derived from the cross between Hiberna and Pfyner was used to analyze the inheritance of yield and its components in barley by generation mean analysis and to map the corresponding QTLs (quantitative trait loci) by microsatellite markers. Generation mean analysis suggested that both additive and dominance effects were important for most of the traits evaluated, but dominance and non-allelic interaction had a more pronounced effect for days to maturity, number of grains per spike, spike length and plant height. The highest heritability was obtained for number of tillers, indicating that this trait is controlled by additive effects. The additive effects played major role in the inheritance of grain yield per plant, since heritability of this trait was low. The linkage map constructed by 159 microsatellite markers covered a total length of about 1030.5 cM. Using the method of composite interval mapping 2, 4, 2, 4, 1, 4 and 7 QTLs were detected for days to maturity, number of tillers, 1000-grain weight, plant height, spike length, number of grains per spike and grain yield, respectively. Ten QTLs had corresponding occurrences with the QTLs reported earlier, indicating that these QTLs are stable across genetic backgrounds. The results of this study also showed that, grain yield per plant controls with several minor genes.

Hypericum perforatum L. is a medicinal plant abounding with secondary metabolites which have clinically proven anti-inflammatory, antiviral, antifungal, and antidepressant activities. In this study, the genetic diversity of 29 accessions from eight populations collected from eight provinces (Azerbaijan, Gilan, Tehran, Semnan, Kurdistan, Lorestan, Golestan and Ardabil) were assessed using Inter Simple Sequence Repeat (ISSR) markers. Twelve primers containing different simple sequence repeats (microsatellite) were used. The primers produced between 11 to 26 bands. Totally the markers produced 221 amplification products, out of which 196 bands were polymorphic. The results showed that polymorphism information content (PIC) of primers was 0.37. Primers 841Y-UBC and UBC-807 had the highest PIC (0.41). Cluster analysis based on Jacquard’s similarity coefficient using Unweight Pair Group Method with Arithmetic mean (UPGMA) indicated wide range of diversity across the studied accessions. The highest genetic distance was observed between 23335 (Ardabil) with 17982 and 14206 (both of West Azerbaijan) accessions and between 133337 and 17982 accessions (Gilan and Azerbaijan) revealing closer genetic relationship. The least genetic distance was observed between 13180 and 13347 from Gilan. Molecular variation within and among the populations (within and among provinces) were estimated 78% and 22% of total variance, respectively. The distribution reflects high genetic diversity between the accessions in each geographical area. The results revealed that ISSR markers could be efficiently used for genetic differentiation of the St. John’s Wort accessions.