Morphological and molecular characterization of xOrchiaceras bergonii (Nanteuil) E.G. Cam

Abstract

Specimens of the orchid hybrid xOrchiaceras bergonii and of the two putative parental species Orchis simia and Aceras anthropophorum from Southern Italy were examined by using both morphology and molecular techniques. Hybrid morphological characters and protein profiles were intermediate between those of the two putative parental species. Chloroplast DNA restriction fragment polymorphism analysis showed differences between O. simia and A. anthropophorum. Hybrid restriction patterns were completely identical to the ones of O. simia. The data presented here confirm both the hybrid nature of xO. bergonii and that O. simia and A. anthropophorum are the parental species. Results also show that O. simia is the maternal lineage of the hybrid. The usefulness of a molecular approach in detecting maternal lineages in orchid hybrids as related to the understanding of the reproductive mechanism in parental species and to the direction of gene flow in hybrid formation are discussed.     

DNA barcoding and genetic fidelity assessment of micropropagated Aenhenrya rotundifolia (Blatt.) C.S. Kumar and F.N. Rasm.: a critically endangered jewel orchid

Aenhenrya rotundifolia is a critically endangered terrestrial jewel orchid. It is monotypic and endemic to evergreen forests of southern western ghats of India. In the present study, identification of this plant species is validated with DNA barcoding using matK and rbcL chloroplast markers. Further, germ-free juvenile axillary bud explants were cultured on Mitra medium supplemented with different kinds of cytokinins like 6-benzyladenine, 6-furfurylaminopurine, N⁶-(Δ²-isopentyl) adenine, thidiazuron, zeatin and meta-topolin as well as auxins such as α-naphthaleneacetic acid, indole-3-acetic acid and indole-3-butyric acid at different concentrations and combinations for successful proliferation and establishment in vitro. After 12 weeks of culture, axillary bud explants produced an average of 30.12 ± 0.71 shoots per explant, 3.87 ± 0.06 cm shoot length, 1671 ± 2.82 mg fresh mass of proliferated shoots with a proliferation frequency of 100% on Mitra medium supplemented with 6.20 µM meta-topolin and 2.25 µM thidiazuron. No root formation was observed in in vitro proliferated microshoots. However, tiny hair like projections were observed in some elongated shoots on Mitra medium pertaining to 5.37 µM NAA. The tiny hair like structure bearing plantlets were hardened and acclimatized with 100% survival rate in the polytunnel chamber. After 8–10 months of establishment ex vitro, flowering was observed. Additionally, the genetic fidelity of in vitro derived plants was tested with ISSR and SCoT marker profiling. The test results revealed that the plants derived from the protocol has 99% genetic similarity to that of the donor mother plant. This study can be applied in forensic interventions of this species, describes the maintenance of germplasm in vitro and establishment of new viable population in its original habitats by restoring existing sites of this critically endangered jewel orchid.     

Start codon targeted (SCoT) polymorphism-based genetic relationships and diversity among populations of <Emphasis Type="Italic">Tecomella undulata</Emphasis> (Sm.) Seem—an endangered timber tree of hot arid regions

Tecomella undulata (Sm.) Seem commonly called Rohida or Desert teak (family bignoniaceae) is an important agroforestry tree having an important pharmacological and therapeutic uses. Its distribution is restricted to hot arid regions of India and Pakistan having <150 to 500 mm annual rainfall. Genetic diversity status of this important endangered timber tree species designated state flower of Rajasthan remains unrevealed. Genetic diversity of 21 populations (108 accessions) encompassing yellow, red and orange coloured flower bearing morphotypes collected from all 12 districts of western Rajasthan, India, has been examined using start codon targeted (SCoT) polymorphism for the first time. Fingerprinting with 22 SCoT primers (out of 36 screened) generated 294 amplicons of 100 to 3000 bp size, of which 212 (71.6%) were polymorphic. Amplicon number varied from 4 (SCoT-9) to 24 (SCoT-15) with an average of 13.4 amplicons per primer. Average polymorphism information content (PIC), Nei’s diversity index (H) and Shannon index (I) were 0.54, 0.22 and 0.36, respectively. Dendrogram generated using unweighted pair-group method with arithmetic mean (UPGMA) delineated the 108 accessions into 5 clusters while 2 accessions out grouped. Principal coordinate analysis (PCoA) also revealed similar clustering. High level of genetic differentiation among accessions/populations was attributed to cross pollination and continuous evolution under harsh agro-climatic conditions.     

Genetic diversity and taxonomic studies of date plum (Diospyros lotus L.) using morphological traits and SCoT markers

Date plum persimmon (Diospyros lotus L.) is an important fruit crop in China due to its better compatibility as a major root stock for Diospyros kaki Thunb. The objective of this study was to reveal the diversity and taxonomic status based on morphological and molecular markers for 26 date plum persimmon accessions from different ecogeographical areas. Significant variability was observed in the 26 date plum persimmon accessions using the analysis of 5 quantitative and 16 qualitative morphological characters of branches, fruits and seeds. Molecular diversity was analyzed using start codon targeted (SCoT) markers. A total of 118 bands were produced with 11 SCoT primers; genetic similarity was ranged from 0.42 to 0.83, which indicating higher genetic variation among accessions. Based on the cluster results of morphological and molecular data, the results showed that date plum persimmon may be divided into five taxonomic types which including male date plum persimmon, rounded seedless date plum persimmon, rounded seedy date plum persimmon, obround seedless date plum persimmon, and oblate seedy date plum persimmon.     

Molecular identification of root fungal associates in Orchis pauciflora Tenore

Abstract

The terrestrial orchid, Orchis pauciflora Ten., growing in poor grassland and garrigue of Central Mediterranean region, is local and rare and has been included in the red lists of several Italian regions. We investigated the diversity of fungal associates in O. pauciflora adult plants collected in two protected areas of Tuscany (Central Italy). Genomic DNA was extracted from mycorrhizal roots of 12 orchid plants and the fungal ITS were amplified and sequenced. Several fungal associates, belonging to different taxa of basidiomycetes (Tulasnellaceae) and ascomycetes such as Leptodontidium, Exophiala and Phialophora species, were recovered. The trophic role of these fungi and their impact on O. pauciflora growth and conservation are discussed.     

Diversity and relationships of Crocus sativus and its relatives analysed by inter-retroelement amplified polymorphism (IRAP)

Background and Aims: Saffron (Crocus sativus) is a sterile triploid (2n = 3x = 24) cultivated species, of unknown origin from other diploid and polyploid species in the genus Crocus (Iridaceae). Species in the genus have high morphological diversity, with no clear phylogenetic patterns below the level of section Crocus series Crocus. Using DNA markers, this study aimed to examine the diversity and relationships within and between species of Crocus series Crocus.Methods: Eleven inter-retroelement amplified polymorphism (IRAP) primers were used in 63 different combinations with 35 single-plant accessions of C. sativus and related Crocus species in order to determine genetic variability and to conduct phylogenetic analysis.Key Results: A total of 4521 distinct polymorphic bands from 100 bp to approx. 4 kb were amplified; no fragment specific to all accessions of a single species was amplified. The polymorphic information content (PIC) values varied from approx. 0·37 to approx. 0·05 (mean 0·17 ± 0·1) and the major allele frequency had a mean of 0·87. High levels of polymorphism were identified between accessions of the six species of Crocus series Crocus related to C. sativus, with further variation between the species. In contrast, no polymorphisms were seen among 17 C. sativus accessions obtained in the region from Kashmir through Iran to Spain.Conclusions In contrast to the intraspecific variability seen in other Crocus species, C. sativus has minimal genetic variation, and it is concluded that the triploid hybrid species has most probably arisen only once. The data show that saffron is an allotriploid species, with the IRAP analysis indicating that the most likely ancestors are C. cartwrightianus and C. pallasii subsp. pallasii (or close relatives). The results may facilitate resynthesizing saffron with improved characteristics, and show the need for conservation and collection of wild Crocus.     

Biosynthesis of salep mannan

A particulate enzyme system, isolated from growing orchid tubers (Orchis morio), was shown to catalyse the transfer of mannose from guanosine-diphosphate-mannose-¹⁴C and its incorporation into alkali-insoluble mannan with the same type of linkage [β(1 → 4)-d-mannopyranosyl] as is contained in the naturally-occurring reserve polysaccharide.     

Siberian wild rye (Elymus sibiricus L.): Genetic diversity of germplasm determined using DNA fingerprinting and SCoT markers

Elymus sibiricus is a perennial, self-pollinating, allotetraploid grass native to northern Asia. It is widely used in cultivated pastures and natural grassland due to excellent cold and drought tolerance, good forage quality, and adaptability to a variety of habitats. Information on the genetic diversity and variation among worldwide E. sibiricus germplasm is limited but necessary for germplasm collection, conservation and effective commercial use. In this study we ana lyzed genetic diversity and variation of 69 E. sibiricus accessions from the species range and constructed DNA fingerprinting profiles of 24 accessions using SCoT markers. A total of 173 bands were generated from 16 SCoT primers, 154 of which were polymorphic with 89.0% of polymorphic bands (PPB) occurring at the species level. The PPB within 8 geographical regions ranged from 2.3 to 54.3 %. Genetic variation was greater within geographical regions (57.9%) than between regions (42.1%). The 24 accessions from Qinghai-Tibet Plateau, Mongolia Plateau, Kazakhstan, and Russia were distinguished by their unique fingerprinting. This is the first report using SCoT markers for identifying cultivars and accessions of E. sibiricus. The DNA fingerprinting profiles of E. sibiricus were useful in germplasm collection and identification. The genetic diversity of worldwide E. sibiricus germplasm has been substantially affected by ecogeographical factors. Our results suggest that collecting and evaluating E. sibiricus germplasm from major geographic regions and unique environments broadens the available genetic base and illustrates the range of variation.     

Analysis of genetic diversity and relationships among genus Lycoris based on start codon targeted (SCoT) marker

Genetic diversity and relationship of Lycoris species were investigated using SCoT marker analysis. Of 57 SCoT primers screened, 23 SCoT primers were identified to be high polymorphism. A total of 154 DNA bands with size varied from 0.2 kb to 2.5 kb were amplified, and 131 (82.5%) of them were polymorphic. The average number of polymorphic DNA band per primer was 5.7. Based on Nei's similarity coefficients and genetic distances, total of 43 accessions from 14 species of the genus Lycoris tested were clustered into four groups. Group I consisting of 17 accessions was further divided into two subgroup (Ia and Ib). Subgroup Ia included four species with red flower and 22 (2n) chromosomes. Subgroup Ib contained Lycoris haywardii and Lycoris albiflora which were natural hybrids with oyster white flower. Group II consisted of three species with yellow flower and 16 (2n) chromosomes. Group III was composed of Lycoris Squamigera, Lycoris incarnata and all of hybrids whose flower color was variegated. Group IV only has one species (Lycoris sprengeri) whose petal was a mixture of pink and blue. Notably, the polymorphism generated by SCoT was associated with flower color and chromosome number in this genus plants. The present data provide high-valued information for the management of germplasm, genetic improvement, and conservation of the genetic resources of Lycoris species, important horticulture and medical plants.     

804. OPHRYS INSECTIFERA

Ophrys insectifera L., fly orchid is described and illustrated. Details of its relationships, pollination biology, distribution and conservation status are presented. Possible reasons for its ongoing decline in the UK are suggested. Cultivation and propagation are discussed.     

Investigation and Analysis of Genetic Diversity of Diospyros Germplasms Using SCoT Molecular Markers in Guangxi

Background

Knowledge about genetic diversity and relationships among germplasms could be an invaluable aid in diospyros improvement strategies.

Methods

This study was designed to analyze the genetic diversity and relationship of local and natural varieties in Guangxi Zhuang Autonomous Region of China using start codon targeted polymorphism (SCoT) markers. The accessions of 95 diospyros germplasms belonging to four species Diospyros kaki Thunb, D. oleifera Cheng, D. kaki var. silverstris Mak, and D. lotus Linn were collected from different eco-climatic zones in Guangxi and were analyzed using SCoT markers.

Results

Results indicated that the accessions of 95 diospyros germplasms could be distinguished using SCoT markers, and were divided into three groups at similarity coefficient of 0.608; these germplasms that belong to the same species were clustered together; of these, the degree of genetic diversity of the natural D. kaki var. silverstris Mak population was richest among the four species; the geographical distance showed that the 12 natural populations of D. kaki var. silverstris Mak were divided into two groups at similarity coefficient of 0.19. Meanwhile, in order to further verify the stable and useful of SCoT markers in diospyros germplasms, SSR markers were also used in current research to analyze the genetic diversity and relationship in the same diospyros germplasms. Once again, majority of germplasms that belong to the same species were clustered together. Thus SCoT markers were stable and especially useful for analysis of the genetic diversity and relationship in diospyros germplasms.

Discussion

The molecular characterization and diversity assessment of diospyros were very important for conservation of diospyros germplasm resources, meanwhile for diospyros improvement.     

Analysis of molecular genetic diversity in a representative collection of foxtail millet [Setaria italica (L.) P. Beauv.] from different agro-ecological regions of India

Foxtail millet [Setaria italica (L.) P. Beauv.], an important crop of East Asia is known for its drought tolerance and was once an indispensible crop of vast rainfed areas in semi-arid regions in India. In India it is cultivated in Andhra Pradesh, Karnataka, Maharashtra, Tamil Nadu, Rajasthan, Madhya Pradesh, Uttar Pradesh and north eastern states. The grain finds use in several local recipes such as roti (bread), jaula, singal, sirol. Foxtail millet grain contains 12.3 % protein, 4.7 % fat, 60.6 % carbohydrates, and 3.2 % ash. The present study was conducted to analyse the genetic diversity among foxtail accessions from different states of India and a few exotic accessions using RAPD and ISSR techniques and identify diverse accessions for use in variety improvement programmes. A set of 125 foxtail millet accessions selected from 11 different agro-ecological regions of India were analyzed using random amplified polymorphic DNA (RAPD) and inter simple sequence repeat (ISSR) marker techniques. A total of 146 (115 RAPD and 31 ISSR) scoreable markers were generated with 16 RAPD and four ISSR primers. The dendrogram generated using Nei’s genetic distances and principal component analyses revealed presence of two clusters and two subclusters in group I. The accessions from Andhra Pradesh, Karnataka, Maharashtra and Uttarakhand were more diverse since they were distributed in both the clusters. There was no clear geographical differentiation observable. The bootstrap support for the major groups identified was strong (above 80 %) indicating good statistical support. The average value of Nei and Li’s genetic distance was lowest (0.081) for accessions from West Bengal while the collections from Karnataka showed highest dissimilarity (average genetic distance = 0.239). The average genetic distance for all 125 accessions together was 0.177 indicating presence of only moderate genetic diversity in the collections. The analysis of molecular variance indicated that only 2.76 % variation was explained by variations among the groups and 11.55 % among populations within groups. However the percentage of variation observed within populations was high (85.68). The value of Fst was observed to be very low (0.028) indicating low differentiation of the accessions analysed. The population genetic analysis carried out indicates that highest number of alleles per locus (1.745 ± 0.438) was observed for Andhra Pradesh with 35 accessions. When four eco-geographic regions were considered, the southern region comprising AP, Karnataka and TN showed the highest number of alleles per locus (1.787 ± 0.411). The value of Gst was lowest for south (0.123) and highest for central west (0.455). This indicated that all the landraces from south share common alleles. The gene flow between the accessions from different regions was also observed to be high with the highest migration (3.557) recorded for south.     

A comparative assessment of morphological and molecular characterization among three Ziziphus species

Genetic variability of 84 accessions of three Ziziphus species including Z. spina-christi, Z. nummularia and Z. mauritiana were analyzed using a combination of morphological traits and translation initiation codon (ATG) polymorphism. Both morphological and molecular data revealed a high level of inter and intra specific variations among the accessions. Accordingly, 90.49% of amplified fragments were polymorphic among the accessions with the mean values of 0.37 for polymorphic information content (PIC), 3.31 for resolving power (RP), and 1.95 for marker index (MI). The phylogenetic clustering clearly delineated the entire germplasm into three well supported distinct clusters according to the species sources. According to the Nei''s genetic identity, Z. spina-christi and Z. nummularia were the most similar species and had high differentiation with Z. mauritiana. Moreover, the highest values for Shannon’s information index (I = 0.505) and gene diversity (h = 0.347) were recorded in Z. spina-christi indicating there is higher genetic diversity compared with two other species. Four private alleles were identified in two species which could be beneficial for accessions authentication in argumentative situations. Moreover, results of the Mantel test showed there were moderate correlation between molecular and morphological matrices. In addition, estimation of bivariate correlations revealed there were significant positive and negative correlations between different variables, which offer a practical application of this information during phenotype based selection in ber improvement programs. The results of this investigation highlight the efficiency of translation initiation codon polymorphism for genetic characterization and accurate authentication of Ziziphus accessions as well as detecting and tagging morphologically important traits in this genus that would be helpful for implementation of effective conservation strategies and even broaden current genetic diversity.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12298-021-01000-7.     

Polyploidy and aneuploidy inOphrys,Orchis, andAnacamptis (Orchidaceae)

Studies on chromosome numbers and karyotypes in Orchid taxa from Apulia (Italy) revealed triploid complements inOphrys tenthredinifera andOrchis italica. InO. tenthredinifera there is no significant difference between the diploid and the triploid karyotypes. The tetraploid cytotype ofAnacamptis pyramidalis forms 36 bivalents during metaphase I in embryo sac mother cells. Aneuploidy was noticed inOphrys bertolonii ×O. tarentina with chromosome numbers n = 19 and 2n = 38. There were diploid (2n = 2x = 36), tetraploid (2n = 4x = 72), hexaploid (2n = 6x = 108) and octoploid (2n = 8x = 144) cells in the ovary wall of the diploid hybridOphrys apulica ×O. bombyliflora. Evolutionary trends inOphrys andOrchis chromosomes are discussed.     

ISSR and SCoT for evaluation of hereditary differences of 29 wild plants in Al Jubail Saudi Arabian

This survey is concerned with the hereditary differences of 29 wild plants collected from fifteen different regions in Al Jubail, Saudi Arabia using two molecular marker systems, viz. inter simple sequence repeat (ISSR) and start codon targeted (SCoT) molecular markers. Ten ISSR and ten SCoT primers amplified a total of 142 and 163 bands with a 87% and 84% polymorphism, respectively. The average number of polymorphic bands for each pair of ISSR and SCoT primers combinations was 12.4 and 13.7, respectively. The highest genetic similarity for ISSR (0.97) and SCoT (0.90) were recognized between Zygophyllum qatarense-22 and Juncus rigidus-23, and between Zygophyllum qatarense-28 and Zygophyllum qatarense-29, whereas the lowest was (0.59) differentiated between Zygophyllum qatarense-6 and Salsola imbricate-18 for ISSR and between Cyperus conglomeratus-7 and Halopeplis perfoliata-14 for SCoT. This considers confirmed the value of molecular techniques such as ISSR and SCoT to assess the hereditary differences among the selected 29 weeds for hereditary preservation and plant enhancement.     

Symbiotic seed germination of Habenaria macroceratitis (Orchidaceae), a rare Florida terrestrial orchid

The rapid loss of native orchid habitat throughout ecologically important areas (e.g., Florida) has prompted researchers to develop appropriate plans for the propagation and reintroduction of many native orchid species. Ideally, symbiotic orchid seed germination methods are utilized in the production of orchid seedlings to be used in plant reintroduction programs. In the current study we (1) describe an efficient symbiotic seed germination protocol to germinate seeds of the rare sub-tropical terrestrial orchid Habenaria macroceratitis; (2) discuss the in vitro fungal specificity demonstrated by this species; and (3) describe the effects of three photoperiods (0/24 h, 16/8 h, 24/0 h L/D) on in vitro symbiotic seed germination of H. macroceratitis. Six fungal mycobionts were isolated from both vegetative and flowering plants of H. macroceratitis from two geographically distinct sites. Symbiotic seed germination percent was highest (65.7%) and protocorm development was most advanced (Stage 2) when seeds were cultured with fungal mycobiont Hmac-310. Seeds of H. macroceratitis demonstrated a degree of specificity toward fungal mycobionts isolated from plants originating from the same site where seed was collected. Continual darkness (0/24 h L/D) inhibited initial seed germination (Stage 1; 17.1%), but stimulated subsequent protocorm development (Stage 2; 53.5%). These findings will aid in developing an efficient symbiotic seed germination protocol for the conservation of this rare Florida terrestrial orchid, and may prove useful in the conservation of other sub-tropical terrestrial orchid species.     

Start Codon Targeted (SCoT) marker reveals genetic diversity of Dendrobium nobile Lindl., an endangered medicinal orchid species

Genetic variability in the wild genotypes of Dendrobium nobile Lindl. collected from different parts of Northeast India, was analyzed using a Start Codon Targeted (SCoT) marker system. A total of sixty individuals comprising of six natural populations were investigated for the existing natural genetic diversity. One hundred and thirty two (132) amplicons were produced by SCoT marker generating 96.21% polymorphism. The PIC value of the SCoT marker system was 0.78 and the Rp values of the primers ranged between 4.43 and 7.50. The percentage of polymorphic loci (Pp) ranging from 25% to 56.82%, Nei's gene diversity (h) from 0.08 to 0.15 with mean Nei's gene diversity of 0.28, and Shannon's information index (I) values ranging from 0.13 to 0.24 with an average value of 0.43 were recorded. The gene flow value (0.37) and the diversity among populations (0.57) demonstrated higher genetic variation among the populations. Analysis of molecular variance (AMOVA) showed 43.37% of variation within the populations, whereas 56.63% variation was recorded among the populations. Cluster analysis also reveals high genetic variation among the genotypes. Present investigation suggests the effectiveness of SCoT marker system to estimate the genetic diversity of D. nobile and that it can be seen as a preliminary point for future research on the population and evolutionary genetics of this endangered orchid species of medicinal importance.     

Higher clonal integration in the facultative epiphytic fern Selliguea griffithiana growing in the forest canopy compared with the forest understorey

Background and Aims The advantage of clonal integration (resource sharing between connected ramets of clonal plants) varies and a higher degree of integration is expected in more stressful and/or more heterogeneous habitats. Clonal facultative epiphytes occur in both forest canopies (epiphytic habitats) and forest understories (terrestrial habitats). Because environmental conditions, especially water and nutrients, are more stressful and heterogeneous in the canopy than in the understorey, this study hypothesizes that clonal integration is more important for facultative epiphytes in epiphytic habitats than in terrestrial habitats.Methods In a field experiment, an examination was made of the effects of rhizome connection (connected vs. disconnected, i.e. with vs. without clonal integration) on survival and growth of single ramets, both young and old, of the facultative epiphytic rhizomatous fern Selliguea griffithiana (Polypodiaceae) in both epiphytic and terrestrial habitats. In another field experiment, the effects of rhizome connection on performance of ramets were tested in small (10 × 10 cm²) and large (20 × 20 cm²) plots in both epiphytic and terrestrial habitats.Key Results Rhizome disconnection significantly decreased survival and growth of S. griffithiana in both experiments. The effects of rhizome disconnection on survival of single ramets and on ramet number and growth in plots were greater in epiphytic habitats than in terrestrial habitats.Conclusions Clonal integration contributes greatly to performance of facultative epiphytic ferns, and the effects were more important in forest canopies than in forest understories. The results therefore support the hypothesis that natural selection favours genotypes with a higher degree of integration in more stressful and heterogeneous environments.     

Cervicovaginal bacterial communities in reproductive-aged Tanzanian women with Schistosoma mansoni,Schistosoma haematobium,or without schistosome infection

Schistosome infection is recognized as a potentially modifiable risk factor for HIV in women by the World Health Organization. Alterations in cervicovaginal bacteria have been associated with HIV acquisition and have not been studied in schistosome infection. We collected cervical swabs from Tanzanian women with and without S. mansoni and S. haematobium to determine effects on cervicovaginal microbiota. Infected women were treated, and follow-up swabs were collected after 3 months. 16S rRNA sequencing was performed on DNA extracted from swabs. We compared 39 women with S. mansoni with 52 uninfected controls, and 16 with S. haematobium with 27 controls. S. mansoni-infected women had increased abundance of Peptostreptococcus (p = 0.026) and presence of Prevotella timonesis (p = 0.048) compared to controls. High-intensity S. haematobium infection was associated with more diverse cervicovaginal bacterial communities than uninfected controls (p = 0.0159). High-intensity S. mansoni infection showed a similar trend (p = 0.154). At follow-up, we observed increased alpha diversity in S. mansoni (2.53 vs. 1.72, p = 0.022) and S. haematobium (2.05 vs. 1.12, p = 0.066) infection groups compared to controls. Modifications in cervicovaginal microbiota, particularly increased diversity and abundance of taxa associated with bacterial vaginosis and HIV (Peptostreptococcus, Prevotella), were associated with schistosome infection.     

Genetic variability and structure of Quercus brantii assessed by ISSR,IRAP and SCoT markers

Persian oak (Quercus brantii Lindl.) is one of the most important woody species of the Zagros forests in Iran. Three molecular marker techniques: start codon targeted (SCoT), inter-simple sequence repeat (ISSR) and inter-retrotransposon amplified polymorphism (IRAP) markers were compared for fingerprinting of 125 individuals of this species collected from different geographical locations of north-west of Iran. A total of 233 bands were amplified by 18 ISSR primers, of which 224 (96.10%) were polymorphic, and 126 polymorphic bands (97.65%) were observed in 129 bands amplified by 10 IRAP primers. Besides, 118 bands were observed for all 10 SCoT primers, of which 113 were polymorphic (95.71%). Average polymorphism information content (PIC) for ISSR, IRAP and SCoT markers was 0.30, 0.32 and 0.38, respectively, and this revealed that SCoT markers were more informative than IRAP and ISSR for the assessment of diversity among individuals. Based on the three different molecular types, cluster analysis revealed that 125 individuals taken for the analysis can be divided into three distinct clusters. The Jaccard's genetic similarity based on the combined data ranged from 0.23 to 0.76. These results suggest that efficiency of SCoT, IRAP and ISSR markers was relatively the same in fingerprinting of individuals. All molecular marker types revealed a low genetic differentiation among populations, indicating the possibility of gene flow between the studied populations. These results have an important implication for Persian oak (Q. brantii) germplasm characterization, improvement, and conservation.