Inter-simple Sequence Repeat Markers Research Articles

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In Egypt, the taxonomic identity of the taxa under genus Retama Raf., 1838 (Fabaceae) is still unclear and its morphological resemblance precludes its identification. The current study aims to resolve the taxonomic identity of the species belonging to genus Retama in Egypt and clarify the morphological, molecular, and geographic distribution characterised each species. To achieve these goals, the fresh and herbarium Retama specimens were used for morphological investigations using 94 macro-morphological characters while the Inter Simple Sequence Repeats (ISSR) markers were used for the molecular identity. This revision revealed the identification of two distinct species namely: Retama raetam (Forsskk.) Webb. and Retama monosperma (L.) Boiss with five forms under R. raetam (Forms 2, 4, 6, 7, and 8). In addition to Form 5 from under R. monosperma; the morphological and molecular identities of forms showed variations in the meanwhile it's clustering were congruent. The geographic distribution of the Retama taxa in Egypt was elucidated. This study highlights the urgent need for Retama species conservation, due its vulnerability to climatic change.

Evaluation of Wild Almond Genotypes Grown as a Rain-fed Crop in Sulaimani Governorate using RAPD and ISSR Markers

Almond is considered the most common and essential nut grown in the rainfed area. It has many species wildly distributed in the Iraqi Kurdistan region, which are called Chaqala by local people. To understand and improve the characteristics of the cultivated almonds, a comprehensive study of wild almonds in terms of population structure and genetic diversity is needed to transfer new traits into the domesticated almonds. So, twelve different genotypes were collected and analyzed using random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) markers. The results revealed polymorphic bands for both markers, the mean value of 5.8 for the RAPD marker and 7.8 for the ISSR marker was also documented. The polymorphic information content (PIC) values were obtained for RAPD primes that range between (0.64-0.85) and ISSR primers were also verified between (0.53-0.91), which shows the discriminatory power of these markers. “Jaccard similarity coefficients” were obtained between 0.34 (G11 vs. G12) to 0.77 (G1 vs. G10), and clustered into four groups with a mean similarity (0.65) for ten RADP markers. For ten ISSR markers, 0.35 (G8, G10) to 0.79 (G6 vs. G11) were also observed, which is clustered into a mean similarity (0.65). Structure analysis of RAPD and ISSR showed two major groups. Overall, these outcomes showed the diversity between the studied genotypes and among groups which are highly important for future almond breeding and conservation programs.

The development of an in vitro propagation and conservation system for the endangered serpentine fern Asplenium cuneifolium Viv.

Asplenium cuneifolium Viv. is an endangered fern species restricted to European serpentine rocks, which face a risk of being easily damaged by both natural and anthropogenic agents. Establishing a comprehensive system of effective micropropagation and long-term storage of this species is therefore desirable. Freshly collected spores of A. cuneifolium were subjected to direct storage at 5 °C and in liquid nitrogen (LN). The viability of spores stored at 5 °C decreased by 10% after 1 year, whereas storage in LN did not change the initial spore viability even after 3 years. For the initiation of the gametophyte culture, disinfected spores were sown onto half-strength Murashige and Skoog medium (½MS) supplemented with 0.06 M sucrose. Following 6 months, abundant proliferation of secondary gametophytes was achieved. For the cryopreservation of gametophytes, encapsulation-vitrification and encapsulation-dehydration, were compared. Of these two methods, encapsulation-vitrification ensured survival of gametophytes of 64.5–93%, while encapsulation-dehydration guaranteed their 100% viability. The acceleration of syngamy on secondary gametophytes was achieved using a medium with macro- and micronutrients reduced to the 1/8 of the MS free of NH4NO3 and vitamins. The syngamic sporophytes could be multiplied by somatic embryogenesis (SE) induced on etiolated stipe explants in an ½MS medium devoid of any plant growth regulators. Adding 0.3 M of sucrose to the medium almost quadrupled the efficiency of the SE. The genetic stability of gametophytes after cryopreservation, as well as sporophytes obtained from them, was confirmed by flow cytometry, amplified fragment length polymorphism, and inter-simple sequence repeat markers.

Identification of Morphological and Physiochemical Characteristics, Flowering Periods, and Genetic Relationship of Citrus Species

Variety improvement program of citrus in Indonesia has still been prioritized, therefore, characterization and identification of varieties within and/or among citrus species are absolutely required in order to obtain desired varieties based on market demand needs. The aim of this research was to determine morphological characteristics, flowering periods, and the genetic relationship of four citrus species. This study was carried out at Indonesia Citrus and Subtropical Fruit Research Institute (ICISFRI). A total of 12 varieties derived from Citrus reticulata Blanco, Citrus sinensis L. Osbeck, Citrus aurantifolia (Christm.) Swingle), and Citrus lemon (L.) Burm. F was used for morphological description. The genetic relationship was evaluated by morphological and molecular analyses using Inter-simple Sequence Repeat (ISSR). The result showed that variations of morphological characters were identified either within or among four citrus species. Citrus reticulata Blanco had the highest physiochemical contents. In terms of flowering periods, varieties that belong to Citrus reticulata Blanco, and Ortaji (Citrus sinensis L. Osbeck) required 9 to 11 days for fully blooming after flower bud; whereas Montaji (Citrus limon (L.) Burm. F) and Nimas (Citrus aurantifolia (Christm.) Swingle) needed 16 days. In both morphological and molecular analyses, 12 varieties were classified into two main clusters, however, some differences were found between the two dendrograms. The genetic relationship of four citrus species based on similarity coefficient ranged from 1 to 25 (morphological analyses) and 0.62 to 0.90 (ISSR marker), respectively. The highest genetic relationship derived from both analyses was performed by Krisma versus Monita, and Krisma versus Orlinda Kuning, respectively. Morphological analyses are still needed to complement molecular analyses in citrus classification in order to produce desired new citrus varieties in order to create sustained citrus agribusiness in Indonesia.

Population Genetic Analysis of Fusarium decemcellulare, a Guaraná Pathogen, Reveals High Genetic Diversity in the Amazonas State, Brazil.

Guaraná is indigenous to the Brazilian Amazon where it has cultural and agroeconomic significance. However, its cultivation is constrained by a disease termed oversprouting of guaraná caused by Fusarium decemcellulare, with yield losses reaching as high as 100%. The disease can affect different parts of the plant, causing floral hypertrophy and hyperplasia, stem galls, and oversprouting of vegetative buds. To date, no study has been conducted characterizing the genetic diversity and population structure of this pathogen. Here, we report genetic diversity and genetic structure among 224 isolates from eight guaraná production areas of Amazonas State, Brazil, that were genotyped using a set of 10 inter-simple-sequence repeat (ISSR) markers. Despite moderate gene diversity (Hexp = 0.21 to 0.32), genotypic diversity was at or near maximum (223 multilocus genotypes among 224 isolates). Population genetic analysis of the 10 ISSR marker fragments with STRUCTURE software identified two populations designated C1 and C2 within the F. decemcellulare collection from the eight sites. Likewise, UPGMA hierarchical clustering and discriminant analysis of principal components of the strains from guaraná resolved these same two groups. Analysis of molecular variance demonstrated that 71% of genetic diversity occurred within the C1 and C2 populations. A pairwise comparison of sampling sites for both genetic populations revealed that 59 of 66 were differentiated from one another (P < 0.05), and high and significant gene flow was detected only between sampling sites assigned to the same genetic population. The presence of MAT1-1 and MAT1-2 strains, in conjunction with the high genotypic diversity and no significant linkage disequilibrium, suggests that each population of F. decemcellulare might be undergoing sexual reproduction. Isolation by distance was not observed (R2 = 0.02885, P > 0.05), which suggests that human-mediated movement of seedlings may have played a role in shaping the F. decemcellulare genetic structure in Amazonas State, Brazil.

&lt;i&gt;Corrigendum to&lt;/i&gt;: Assessing genetic diversity and population structure of Iranian melons (&lt;i&gt;Cucumis melo&lt;/i&gt;) collection using primer pair markers in association with resistance to Fusarium wilt

We evaluated genetic diversity and population structure of Iranian melons (Cucumis melo L.) using combinations of 35 primer pairs: 15 Simple-Sequence-Repeats (SSR); 10 Inter-Simple-Sequence-Repeats (ISSR); and 10 Sequence-related amplified polymorphism (SRAP) markers in association with resistance to melon Fusarium wilt, caused by Fusarium oxysporum f. sp. melonis (FOM ). Genetic similarity was determined by simple matching coefficient (SSM) and dendrogram by clustering-analysis with unweighted pair groups using arithmetic averages (UPGMA). By combining ISSR-SSR-SRAP markers, a high degree of variation among the melons was detected. The mean polymorphism information content (PIC), marker index (MI), effective-number of alleles (I), expected heterozygosity (H), and Nei's gene diversity parameters were 0.392, 0.979, 1.350, 0.551 and 0.225, respectively. According to MI, PIC, I, H, and Nei indices evaluation, ISSR6, ISSR9, SRAP3, SRAP5, SSR3 and SSR6 had the best performance in genetic diversity of the related melons population. The 35 primers yielded a total of 264 bands, of which 142 showed polymorphism. Clustering of genotypes based on resistance to Fusarium wilt, and comparison with grouping on SSR, SRAP and ISSR marker revealed a significant compliance between disease severity and molecular marker dendrograms. Thus, increasing the number of molecular markers for genetic diversity provides a powerful tool for future agricultural and conservation tasks.

Comparative assessment of ISSR, DAMD and RAPD markers for evaluation of genetic diversity of gerbera (Gerbera jamesonii Bolus ex Hooker f.) cultivars

Genetic diversity is the best way to improve available genetic resources for breeding programs in gerbera. In present study, genetic diversity of 22 gerbera cultivars was investigated using inter-simple sequence repeat (ISSR), directly amplified minisatellite DNA (DAMD), and Random Amplified Polymorphic DNA (RAPD) markers. Average polymorphism information content (PIC) for ISSR, DAMD and RAPD markers was 0.40, 0.41 and 0.40, respectively. Cluster analysis for ISSR, DAMD and RAPD divided the cultivars into three distinct clusters. The comparative analysis of the three markers (ISSR, DAMD and RAPD) showed that DAMD had superiority over RAPD and ISSR in characterization of genetic diversity in Gerbera. To our knowledge, this is the first report of a comparison of performance among DAMD, ISSR and RAPD techniques on a set of gerbera genotypes. Overall, our results showed that DAMD markers well represented different genotypes of gerbera diversity.

Assessment of Genetic Diversity in Bupleurum spp. Basing Agronomic Traits, Medicinal Components and ISSR Markers.

Radix bupleuri is one of the bulk medicinal materials in China and it is widely adopted in clinical applications and drug discovery. The investigation of agronomic traits, active component content and genetic diversity in diverse Radix bupleuri germplasms may provide evidence to promote the selection of better strains. In this research, 13 germplasms from various sources were used to investigate the variations between different Radix bupleuri germplasms. Nine biological characteristics were noted in the field, and the levels of the two primary active ingredients were determined using high performance liquid chromatography (HPLC). Moreover, the molecular marker technique of inter-simple sequence repeat (ISSR) and the unweighted pair group method with arithmetic means (UPGMA) were employed to evaluate the molecular genetic diversity. The findings showed that there was a wide range of variation among the many varieties of Radix bupleuri, with coefficients of variation for agronomic traits and active component content ranging from 7.62% to 41.54% and 36.47% to 53.70%, respectively. Moreover, there are different degrees of relationship between the two. Since there was a significant correlation between root weight and saikosaponin content, it was possible to classify a plant based on its weight and anticipate its saikosaponin content. The 13 species were divided into four groups based on their germplasm by genetic markers-based cluster analysis. This indicated the possibility that the component content would not necessarily be related to germplasm and might easily be influenced by environmental factors. The use of ISSR marker technology made it possible to precisely identify the various Radix bupleuri provenances and its counterfeit products. There may be a way to prevent the misunderstandings caused by the appearance and composition of Chinese medicinal substances. In our study, the germplasm of Radix bupleuri that was widely circulated in the market was comprehensively evaluated in terms of agronomic traits, active components and molecular level, and identified by simple means, to provide a theoretical basis for the evaluation and screening of fine germplasms of Radix bupleuri.

Isolation of Pseudomonas syringae pv. Tomato strains causing bacterial speck disease of tomato and marker-based monitoring for their virulence

BackgroundThe bacterial speck disease of tomato caused by a bacterial pathogen Pseudomonas syringae pv. tomato is a most important disease causing severe crop losses.Methods and resultsPresent study was conducted to investigate and characterize the population diversity of P. syringae pv. tomato pathogen isolated from infected tomato plants from various regions of Egypt. Significant variation among the isolates was observed which demonstrated considerable virulence. All isolates were pathogenic and the CFU population recovered from inoculate tomato leaves by isolate Pst-2 was higher than other isolates. Genetic disparity among the isolates was investigated by PCR analysis by amplifying hrpZ gene using random amplified polymorphic DNA (RAPD), sequence-related amplified polymorphism (SRAP), and inter-simple sequence repeats (ISSR) markers. The amplified products for ITS1 were found to have 810 bp length whereas 536 bp length was observed for hrpZ gene using primer pairs (1406-f/23S-r) and (MM5-F, MM5-R) respectively. The restriction analysis of amplified regions “ITS” and hrpZ by using 5 and 4 endonucleases respectively demonstrated slight variation among the bacterial isolates. The results of RAPD, ISSR and SRAP showed higher polymorphism (60.52%) within the isolates which may assist for successful characterization by unique and specific markers based on geographical distribution, origin and virulence intensity.ConclusionThe results of present study suggested that the use of molecular approach may provide successful and valuable information to differentiate and classify P. syringae pv. tomato strains in future for the detection and confirmation of pathogenicity.

Assessment of genetic variation and population structure in Iraqi barley accessions using ISSR, CDDP, and SCoT markers

The objective of this study was to investigate the diversity of 59 accessions of barley using inter simple sequence repeat (ISSR), conserved DNA-derived polymorphism (CDDP), and start codon targeted (SCoT) markers. A total of 391 amplified polymorphic bands were generated using 44 ISSR, 9 CDDP, and 12 SCoT primers that produced 255, 35, and 101 polymorphic bands, respectively. The average values of gene diversity were 0.77, 0.67, and 0.81 for ISSR, CDDP, and SCoT markers, respectively. The mean values of polymorphism information content for ISSR, CDDP and SCoT markers were 0.74, 0.63, and 0.80 respectively. The discrimination power of the three approaches for assessing allelic diversity in barley accessions ranked as follows: SCoT > ISSR > CDDP. The barley accessions were classified and clustered into two main groups. Molecular variance analysis revealed 15, 9, and 14% variability among populations with ISSR, CDDP, and SCoT markers, respectively. The Mantel test results revealed that the three molecular marker matrices had significant positive relationships. The SCoT markers might be useful tools for selecting appropriate parents for a breeding program.

IRAPs in Combination with Highly Informative ISSRs Confer Effective Potentials for Genetic Diversity and Fidelity Assessment in Rhododendron.

The species belonging to the Rhododendron genus are well-known for their colorful corolla. Molecular marker systems have the potential to elucidate genetic diversity as well as to assess genetic fidelity in rhododendrons. In the present study, the reverse transcription domains of long terminal repeat retrotransposons were cloned from rhododendrons and used to develop an inter-retrotransposon amplified polymorphism (IRAP) marker system. Subsequently, 198 polymorphic loci were generated from the IRAP and inter-simple sequence repeat (ISSR) markers, of which 119 were derived from the IRAP markers. It was shown that in rhododendrons, IRAP markers were superior to the ISSRs in some polymorphic parameters, such as the average number of polymorphic loci (14.88 versus 13.17). The combination of the IRAP and ISSR systems was more discriminative for detecting 46 rhododendron accessions than each of the systems on their own. Furthermore, IRAP markers demonstrated more efficiency in genetic fidelity detection of in-vitro-grown R. bailiense Y.P.Ma, C.Q.Zhang and D.F.Chamb, an endangered species recently recorded in Guizhzhou Province, China. The available evidence revealed the distinct properties of IRAP and ISSR markers in the rhododendron-associated applications, and highlighted the availability of highly informative ISSR and IRAP markers in the evaluation of genetic diversity and genetic fidelity of rhododendrons, which may facilitate preservation and genetic breeding of rhododendron plants.

Molecular characterization of some parsley (Petroselinum crispum Mill.) genotypes

Parsley (Petroselinum crispum Mill.), a vegetable whose leaves are consumed, has many benefits for human health. The first step of parsley breeding is the characterization of existing genotypes. In this study, genetic diversity of 12 different parsley genotypes was determined by ISSR (Inter Simple Sequence Repeat) marker system. In the study, 41 of the 130 bands obtained from 16 ISSR primers were found to be polymorphic. The similarity coefficients ranged from 0.86–0.99 for ISSR. The average polymorphism was 31.5% and the number of bands varied between 4 and 14. While the genotypes that are genetically closest to each other were determined as the 5th and 6th genotypes, the most distant genotypes were the 3rd and 8th genotypes. Findings from the present study showed that there were genetic variations among the parsley genotypes examined. The obtained data will enable more effective utilization of the parsley genotypes, the genetic differences of which have been determined for the future breeding programs.

Complete Genome of Rose Myrtle, Rhodomyrtus tomentosa, and Its Population Genetics in Thai Peninsula.

Several parts of rose myrtle, Rhodomyrtus tomentosa, exhibited profound antibacterial and anti-inflammatory activities, suggesting its potential in healthcare and cosmetics applications. During the past few years, the demand for biologically active compounds in the industrial sectors increased. Therefore, gathering comprehensive information on all aspects of this plant species is essential. Here, the genome sequencing using short and long reads was used to understand the genome biology of R. tomentosa. Inter-simple sequence repeats (ISSR) and simple sequence repeats (SSR) markers, and geometric morphometrics of the leaves of R. tomentosa collected across Thai Peninsula, were determined for population differentiation analysis. The genome size of R. tomentosa was 442 Mb, and the divergence time between R. tomentosa and Rhodamnia argentea, the white myrtle of eastern Australia, was around 15 million years. No population structure was observed between R. tomentosa on the eastern and western sides of the Thai Peninsula using the ISSR and SSR markers. However, significant differences in leaf size and shape of R. tomentosa were observed in all locations.

Evaluation of genetic diversity among Saudi Arabian and Egyptian cultivars of alfalfa (Medicago sativa L.) using ISSR and SCoT markers

Medicago sativa (Alfalfa) is valued for its high nutrient content as livestock feed for the production of dairy and meat products globally. The genetic improvement of alfalfa is limited because it is an allogamous autotetraploid. In this study, Inter-simple sequence repeat (ISSR) and start codon targeted (SCoT) markers were used to assess the extent of genetic divergence between sixteen cultivars: twelve from Saudi Arabia and four from Egypt. The genetic diversity was assessed using eleven ISSR and eight SCoT primers. The ISSR primers produce 163 amplified bands with an average of 14.82 bands per primer and 60% polymorphism. The SCoT primers reveal 150 bands, with an average of 18.75 bands per primer and 77% polymorphism. The dendrogram clustered the Saudi and Egyptian cultivars into two distinct populations. The information revealed here will help in the breeding program of alfalfa, which will produce more drought tolerant and high-yielding varieties.

Distribution of genetic variability in mature and progeny populations of Abies alba Mill. from the Polish Western and Eastern Carpathians

This study aimed to compare patterns in the genetic structure of 27 mature stands and the natural regeneration of A. alba in the Eastern and Western Carpathians within the introgression zone of two refugial lineages from the Apennine and Balkan peninsulas. The distribution of the genetic diversity of fir stands was analysed using paternally inherited chloroplast DNA and five nuclear dominant inter simple sequence repeat markers (ISSRs). The study showed that the Balkan haplotype prevailed in both parental and progeny populations, and this haplotype was found in many mature Eastern Carpathian stands. Relatively high levels of genetic diversity were found in the mature stands (effective number of alleles Ne = 1.517, Shannon index I = 0.436, expected heterozygosity He = 0.295) and progeny (Ne = 1.515, I = 0.436 and He = 0.294) of silver fir. The analysis of molecular variance (AMOVA) revealed slight differences among the mature fir stands from the Western and Eastern Carpathians, with a value of 1.1%. According to principal coordinates analysis (PCoA) and STRUCTURE analyses, the populations, including stands of mature and progeny trees, were genetically separated into two groups. Slight genetic differences between the mature and progeny populations in the Polish Carpathians indicate sound gene pool transmission, which is essential for creating new selection and breeding programmes.

Genetic fidelity assessment of wild and tissue cultured regenerants of a threatened orchid, Cymbidium aloifolium using molecular markers

Molecular markers play an effective role in estimating the genetic similarity, variation, diversity, and population structure of different plants. Various factors associated with in vitro culture conditions may cause genetic variation in tissue cultured regenerants. The main goal of the present study was to determine the genetic uniformity of plantlets regenerated through in vitro culture of protocorms, shoot tips, and sodium alginate coated artificial seeds of Cymbidium aloifolium (L.) Sw. and its non-tissue cultured source mother plant using molecular markers such as Random Amplified Polymorphic Deoxyribonucleic acid (RAPD) and Inter Simple Sequence Repeats (ISSR). Ten RAPD and five ISSR primers were used to amplify the genomic DNA isolated from the in vivo plant and randomly selected micropropagated plants. Nine out of ten RAPD primers amplified a total of 256 loci while five ISSR primers amplified a total of 99 loci. The combined data of RAPD and ISSR markers showed low polymorphism. Among the tested plants, dendrograms constructed through UPGMA analysis of RAPD and ISSR markers revealed high genetic similarity between the mother plant and in vitro cultured regenerants. Among the different in vitro regenerants, protocorm-derived plants showed 91% genetic homogeneity to that of the mother plant. Thus, both molecular markers proved to be equally efficient for genetic fidelity studies in C. aloifolium. Hence, this research successfully assessed the genetic fidelity of in vitro cultured plants which could be useful in reintroducing true-to-type plants through plant tissue culture techniques.

On the genetic structure of Eversmannia subspinosa populations in Russia

We have studied the genetic structure of Eversmannia subspinosa (Fisch. ex DC.) B. Fedtsch. populations from the Russian Federation (the Bolshoe Bogdo Mt., the Astrakhan Region; Kegul’ta gully, Republic of Kalmykia) and a number of specimens from the Middle Asia (Kazakhztan and Kyrgyzstan) using inter-simple sequence repeats (ISSR) markers, sequenced nuclear (ITS 1, 2) and chloroplast markers (trnL-trnF, atpB-rbcL, rpl32-trnL(UAG), trnV-ndhC). The analysis of ISSR markers divided samples into three genetic clusters: the population from the Bolshoe Bogdo Mt., the population from the Kegul’ta gully, and samples from the Middle Asia. The population from the Kegul’ta gully appeared to be genetically variable, whereas the population from the Bolshoe Bogdo Mt. exhibited no variation. Populations from the Bolshoe Bogdo and Kegul’ta are more closely related according to the results of the chloroplast DNA analysis. At the same time, these westernmost populations turned out to be related to the samples from the Western Tian Shan: Syr-Darya Karatau, Talas Alatau (Ichkele-Too Mts.) and Kyzylorda Region of Kazakhstan.

Genetic diversity and population structure assessment of Hellenia speciosa from Indian agro-ecological regions using inter-simple sequence repeat markers

Genetic diversity and population structure assessment of Hellenia speciosa from Indian agro-ecological regions using inter-simple sequence repeat markers

Genetic diversity of the threatened &lt;i&gt;Saussurea dorogostaiskii&lt;/i&gt; (Asteraceae) in the Khuvsgul region of Mongolia

&lt;i&gt;Saussurea dorogostaiskii&lt;/i&gt; Palib. (Asteraceae) is a critically endangered medicinal plant in Mongolia and Russia. We studied the genetic variation of &lt;i&gt;S. dorogostaiskii&lt;/i&gt; from three mountains of northern Mongolia. The genetic profile was assessed in 70 individuals from eight populations using five inter-simple sequence repeat markers, producing 53 loci with 96.4% polymorphism across all bands. Shannon’s index (&lt;i&gt;I&lt;/i&gt;) and Nei’s gene diversity (&lt;i&gt;H&lt;/i&gt;) value at the species level of &lt;i&gt;S. dorogostaiskii&lt;/i&gt; are 0.25 and 0.17, respectively. An AMOVA showed high genetic variation among the populations (22% of populations and 32% of mountains), consistent with the high genetic differentiation (&lt;i&gt;G&lt;sub&gt;ST&lt;/sub&gt;&lt;/i&gt; = 0.49) and low gene flow (&lt;i&gt;N&lt;sub&gt;m&lt;/sub&gt;&lt;/i&gt; = 0.51) in &lt;i&gt;S. dorogostaiskii&lt;/i&gt; populations. Eight populations were clustered into two groups, corresponding to their geographic locations. The low within-population genetic diversity and high genetic differentiation among &lt;i&gt;S. dorogostaiskii&lt;/i&gt; populations factor into their endangered designation. This genetic analysis reveals that all populations are equally threatened, and community-based conservation is appropriate for these species.

Chemical Analysis of Essential Oil and Genetic Diversity Using ISSR and SSR Markers in Cultivated Lemongrass (Cymbopogon citratus) Accessions

Leaves and essential oils for therapeutic purposes are important traits in lemongrass (Cymbopogon citratus). In this study, the genetic diversity of ten C. citratus accessions collected around Nigeria was investigated using simple sequence repeat (SSR) and inter simple sequence repeat (ISSR) markers. Also, we determined the chemical content of C. citratus essential oil. In this study, the essential oil was extracted using hydro-distillation and the constituents of the oil were determined with gas chromatography-mass spectrophotometry (GC-MS). The markers produced a total of 47 alleles with a mean PIC value of 0.73 in the accessions. The cluster analysis grouped the accessions into two major groups showing genetic relatedness between the accessions: LG07, LG03 and LG01 are the closest members, while LG08 is very distant from the other accessions. In addition, the factorial analysis categorized the ten accessions into four quadrants, which have some similarities to the dendrogram grouping. GC-MS analysis resulted in the identification of 18 compounds. Essential oils of LG02 and LG03 had a citral content of 49.38 % and 66.47 %, respectively. These results revealed the genetic diversity among the accessions evaluated that can be used to maximize the use of genetic resources of C. citratus varieties.