Tetraploid Level Research Articles

Interspecific transfer of genetic information through polyploid bridges

Hybridization blurs species boundaries and leads to intertwined lineages resulting in reticulate evolution. Polyploidy, the outcome of whole genome duplication (WGD), has more recently been implicated in promoting and facilitating hybridization between polyploid species, potentially leading to adaptive introgression. However, because polyploid lineages are usually ephemeral states in the evolutionary history of life it is unclear whether WGD-potentiated hybridization has any appreciable effect on their diploid counterparts. Here, we develop a model of cytotype dynamics within mixed-ploidy populations to demonstrate that polyploidy can in fact serve as a bridge for gene flow between diploid lineages, where introgression is fully or partially hampered by the species barrier. Polyploid bridges emerge in the presence of triploid organisms, which despite critically low levels of fitness, can still allow the transfer of alleles between diploid states of independently evolving mixed-ploidy species. Notably, while marked genetic divergence prevents polyploid-mediated interspecific gene flow, we show that increased recombination rates can offset these evolutionary constraints, allowing a more efficient sorting of alleles at higher-ploidy levels before introgression into diploid gene pools. Additionally, we derive an analytical approximation for the rate of gene flow at the tetraploid level necessary to supersede introgression between diploids with nonzero introgression rates, which is especially relevant for plant species complexes, where interspecific gene flow is ubiquitous. Altogether, our results illustrate the potential impact of polyploid bridges on the (re)distribution of genetic material across ecological communities during evolution, representing a potential force behind reticulation.

Identifikasi Tingkat Ploidi Tanaman Pisang Menggunakan Flow Cytometer di Jawa Tengah

In Indonesia, banana plants are known to have high genetic diversity, both cultivated and wild bananas. Banana plants are naturally known to have several levels of ploidy, namely diploid, triploid, and tetraploid. This study aims to identify the level of ploidy in banana plants explored in Central Java. The research method used flow cytometer, which analyzes the size of the plant genome, thus providing an overview of the level of ploidy and genetic diversity in banana plant populations. The research samples were banana plant leaves from various exploration locations in Central Java. The identification results show that of the 30 banana plant leaf samples that were successfully analyzed, it is known that the largest number of samples from banana plants that have triploid ploidy level (2n = 3x), namely 15 numbers, diploid ploidy level (2n = 2x) as many as 14 numbers, and found 1 cultivated banana with tetraploid ploidy level (2n = 4x). The results of ploidy level identification can provide guidance for researchers and plant breeders in selecting the right genotype for the development of superior varieties.

Distinct geographic parthenogenesis in spite of niche conservatism and a single ploidy level: A case of Rubus ser. Glandulosi (Rosaceae).

Asexual organisms often differ in their geographic distributions from their sexual relatives. This phenomenon, termed geographic parthenogenesis, has long been known, but the underlying factors behind its diverse patterns have been under dispute. Particularly problematic is an association between asexuality and polyploidy in most taxa. Here, we present a new system of geographic parthenogenesis on the tetraploid level, promising new insights into this complex topic. We used flow cytometric seed screen and microsatellite genotyping to characterise the patterns of distribution of sexuals and apomicts and genotypic distributions in Rubus ser. Glandulosi across its range. Ecological modelling and local-scale vegetation and soil analyses were used to test for niche differentiation between the reproductive groups. Apomicts were detected only in North-western Europe, sexuals in the rest of the range in Europe and West Asia, with a sharp borderline stretched across Central Europe. Despite that, we found no significant differences in ecological niches. Genotypic richness distributions suggested independence of the reproductive groups and a secondary contact. We argue that unless a niche differentiation (resulting from polyploidy and/or hybridity) evolves, the main factors behind the patterns of geographic parthenogenesis in plants are phylogeographic history and neutral microevolutionary processes, such as clonal turnover.

A karyomorphological comparison of seven species of Achillea L. from Kurdistan of Iran

We conducted the present study on seven important medicinal species of Achillea (in a total of 28 populations) in their natural habitats. The results indicated that the populations had a base number (x= 9) and the diploid, tetraploid, and hexaploidy levels were observed. In addition to the inter-species diversity, there was the intra-species genetic diversity as A. millefolium (4x, 6x), A. vermicularis (2x, 4x), A. tenuifolia (2x, 4x), A. Aleppica (2x), A. talagonica (2x), A. biebersteinii, and A. wilhelmsii (4x). Furthermore, studies also indicated that 11 out of 28 populations had 1A symmetry, 15 populations had 2B symmetry, a population had 2A, and another population had 2B. Cluster analysis of cytogenetic variables could differentiate only the species of A. aleppica, A. talagonica and A. wilhelmsii but others could not separate differences between species appropriately, probably due to the superiority of intra-species diversity of populations to inter-species diversity. Furthermore, we found %TF and DRL are useful parameters for differentiating intrachromosomal variation of species.

Autotetraploid Origin of Chinese Cherry Revealed by Chromosomal Karyotype and In Situ Hybridization of Seedling Progenies.

Polyploidy is considered a driving force in plant evolution and diversification. Chinese cherry [Cerasus pseudocerasus (Lindl.) G.Don], an economically important fruit crop native to China, has evolved at the tetraploid level, with a few pentaploid and hexaploid populations. However, its auto- or allo-polyploid origin remains unclear. To address this issue, we analyzed the ploidy levels and rDNA chromosomal distribution in self- and open-pollinated seedling progenies of tetraploid and hexaploid Chinese cherry. Genomic in situ hybridization (GISH) analysis was conducted to reveal the genomic relationships between Chinese cherry and diploid relatives from the genus Cerasus. Both self- and open-pollinated progenies of tetraploid Chinese cherry exhibited tetraploids, pentaploids, and hexaploids, with tetraploids being the most predominant. In the seedling progenies of hexaploid Chinese cherry, the majority of hexaploids and a few pentaploids were observed. A small number of aneuploids were also observed in the seedling progenies. Chromosome 1, characterized by distinct length characteristics, could be considered the representative chromosome of Chinese cherry. The basic Chinese cherry genome carried two 5S rDNA signals with similar intensity, and polyploids had the expected multiples of this copy number. The 5S rDNA sites were located at the per-centromeric regions of the short arm on chromosomes 4 and 5. Three 45S rDNA sites were detected on chr. 3, 4 and 7 in the haploid complement of Chinese cherry. Tetraploids exhibited 12 signals, while pentaploids and hexaploids showed fewer numbers than expected multiples. Based on the GISH signals, Chinese cherry demonstrated relatively close relationships with C. campanulata and C. conradinae, while being distantly related to another fruiting cherry, C. avium. In combination with the above results, our findings suggested that Chinese cherry likely originated from autotetraploidy.

Meiotic Behaviors of Allotetraploid Citrus Drive the Interspecific Recombination Landscape, the Genetic Structures, and Traits Inheritance in Tetrazyg Progenies Aiming to Select New Rootstocks.

Sexual breeding at the tetraploid level is a promising strategy for rootstock breeding in citrus. Due to the interspecific origin of most of the conventional diploid citrus rootstocks that produced the tetraploid germplasm, the optimization of this strategy requires better knowledge of the meiotic behavior of the tetraploid parents. This work used Genotyping By Sequencing (GBS) data from 103 tetraploid hybrids to study the meiotic behavior and generate a high-density recombination landscape for their tetraploid intergenic Swingle citrumelo and interspecific Volkamer lemon progenitors. A genetic association study was performed with root architecture traits. For citrumelo, high preferential chromosome pairing was revealed and led to an intermediate inheritance with a disomic tendency. Meiosis in Volkamer lemon was more complex than that of citrumelo, with mixed segregation patterns from disomy to tetrasomy. The preferential pairing resulted in low interspecific recombination levels and high interspecific heterozygosity transmission by the diploid gametes. This meiotic behavior affected the efficiency of Quantitative Trait Loci (QTL) detection. Nevertheless, it enabled a high transmission of disease and pest resistance candidate genes from P. trifoliata that are heterozygous in the citrumelo progenitor. The tetrazyg strategy, using doubled diploids of interspecific origin as parents, appears to be efficient in transferring the dominant traits selected at the parental level to the tetraploid progenies.

Chromosome numbers in 31 taxa of Asteraceae, Brassicaceae, Poaceae, Hypericaceae, Lamiaceae, Fabaceae and Plantaginaceae from wetlands of Hamadan region in Iran

In this study, we report the somatic chromosome numbers (2n) of 31 taxa belonging to Asteraceae, Brassicaceae, Poaceae, Hypericaceae, Lamiaceae, Fabaceae and Plantaginaceae families from wetlands of Hamadan region in Iran. The chromosome numbers of about half of these species have not been reported in the previous literature. Chromosome number of Ononis spinosa counted chromosomally for the first time at the world level and the chromosome numbers of Erigeron acer, Pulicaria dysenterica, Arctium lappa, Xanthium strumarium, X. spinosum, Barbarea plantaginea, Brachypodium sylvaticum, Polypogon fugax, Prunella vulgaris and Lathyrus chloranthus, are here reported for the first time from Iran. In all taxa 2n was 12, 14, 16, 18, 20, 24, 28, 30, 32 and 42, as a diploid, tetraploid and hexaploid levels. These newly available data are further compared with those previously published for the same or related species.

Asymmetric Reciprocal Crossing Behavior of an Andean Blueberry (V. meridionale) × Lingonberry (V. vitis-idaea) Hybrid.

The fertility and crossing behavior of a tetraploid hybrid of 4x Andean blueberry (V. meridionale) and lingonberry (V. vitis-idaea) was evaluated through a series of crosses. Crosses of the hybrid with highbush blueberry produced divergent results. When used as a female with V. corymbosum males, virtually all offspring were hexaploid, most likely arising from 2n = 4x = 48 female gametes, and 1n = 2x = 24 male gametes. However, when used as a male, tetraploid hybrids were produced, resulting from 1n = 2x = 24 gametes from each parent. To further examine this crossing behavior, the 4x V. meridionale-V. vitis-idaea interspecific hybrid was pollinated with 6x V. virgatum (rabbiteye blueberry). Analogous to the previous crosses, 7x hybrids were produced from the joining of 2n = 4x = 48 female gametes with 1n = 3x = 36 male gametes. Such reciprocal crossing asymmetry is unprecedented. The ability to produce both 6x and 4x offspring from the same V. corymbosum parents allows the potential of bridging a V. meridionale hybrid genotype to both the tetraploid (V. corymbosum) and hexaploid (V. virgatum) commercial crop levels.

Genome Sizes, Ploidy Levels, and Base Compositions of Styrax Species and Cultivars

Styrax L. is a genus of ≈130 species, many with horticultural traits of interest, though sparsely represented in cultivation. Previous studies reporting chromosome counts have established a base chromosome number of x = 8 and provided evidence of diploid, tetraploid, pentaploid, and hexaploid levels within the genus, including the more commonly cultivated Styrax japonicus Siebold & Zucc. being reported as pentaploid. Little has been reported relative to genome size within the Styracaceae. We conducted flow cytometry using fluorochromes propidium iodide (PI) and 4′,6-diamidino-2-phenylindole (DAPI) to estimate relative 2C genome size and ploidy of 47 accessions representing 15 species of Styrax and base composition of a subset of 9 accessions representing 6 species. Cytologic analysis of chromosomes was completed on Styrax confusus Hemsl. for ploidy calibration to genome size. Diploids, tetraploids, pentaploids, hexaploids, and octoploids were identified. Relative 2C genome size ranged from 1.38 to 6.61 pg. This survey confirms published ploidy for Styrax americanus Lam., Styrax obassia Siebold & Zucc., Styrax redivivus (Torr.) L.C.Wheeler (diploid), and S. japonicus (pentaploid); suggests alternate ploidy levels and/or ploidy series for Styrax grandifolius Aiton (diploid) and Styrax hookeri C.B.Clarke (octoploid); and establishes ploidy levels for Styrax glabrescens Benth., Styrax odoratissimus Champ. ex Benth., Styrax officinalis L., Styrax platanifolius Engelm. ex Torr., Styrax ramirezii Greenm., Styrax wilsonii Rehder (diploid), Styrax confusus, Styrax hemsleyanus Diels (tetraploid), and Styrax fortunei Hance (diploid and hexaploid).

Does Inducing Tetraploidy in Vaccinium ovatum Improve Fruit Traits and Plant Architecture?

Vaccinium ovatum (evergreen huckleberry) is an evergreen shrub native to the Pacific Northwest. Evergreen huckleberry is diploid (2n = 2x = 24), but unreduced gametes have been reported that facilitated in interspecific tetraploids. To our knowledge, tetraploid forms of evergreen huckleberry have not previously been evaluated. There is interest in this species as a native, edible, evergreen landscape shrub, but it requires improvement of the fruit and plant qualities for an eventual cultivar release. To obtain variation in plant qualities, we induced polyploidy in a collection of plants in 2013. The purpose of this study was to assess the impacts of polyploidy on the fruit and plant qualities of V. ovatum. This fruit and plant quality study provides a contribution to the scientific knowledge base that is currently lacking for evergreen huckleberries. Plant qualities were determined by measuring plant height and width, obtained in Fall 2017. The fruit volume (mm3) and for soluble solids content (SSC, °Brix) were measured using a digital caliper and a digital refractometer, respectively. Measurements were taken on diploid, mixoploid, and tetraploid (2x, 2x + 4x, 4x) cytotypes, once in 2017, five times over 9 weeks in 2018, and three times over 9 weeks in 2019. Tetraploids had larger fruit than diploids in 2017 (P < 0.0001), suggesting there was a gigas effect from polyploidy in evergreen huckleberries. However, during 2018 and 2019, tetraploid fruit was smaller than that of diploid and mixoploid genotypes. Differences were observed in diploid fruit volume among all years (P < 0.0001) such that 2019 was largest and 2017 was smallest. It is unclear what led to this variation. In tetraploids, SSC was statistically significant among years (P = 0.0002) such that 2017 was highest and 2019 was lowest. Although our preliminary data suggested that induced polyploidy may result in larger fruit, this was not observed in subsequent years, and it does not appear that tetraploids necessarily will have larger or sweeter fruit. However, these tetraploids may facilitate crossing with other species at the tetraploid level as a means for improvement of various traits.

Influence of the Rootstock and the Ploidy Level of the Scion and the Rootstock on Sweet Orange (Citrus sinensis) Peel Essential Oil Yield, Composition and Aromatic Properties

Rootstock is widely used for the cultivation of citrus fruits because it brings resistance or tolerance to diseases or environmental constrains and modulates the fruit quality. Polyploidization is a widespread improvement strategy in citrus. The objective was to evaluate the effect of rootstock and ploidy level on the composition of essential oils. Two trials were conducted, one displaying a ‘Navelina’ orange grafted on three rootstocks and a second combining two ploidy levels (di and tetraploid) of scion (‘Pineapple’ orange) and rootstock (‘Carrizo’ citrange). The composition of peel essential oil (PEO) was analyzed by gas chromatography coupled with mass spectrometry, and a panel of experts analyzed its flavor variation with a triangle test approach. The rootstock influenced the yield and composition of the orange PEO, with a low impact on flavor. Neither the rootstock nor the scion ploidy level affected the PEO yield. Only the tetraploid level of the scion significantly modified the PEO composition, reducing the oxygenated compound fraction. Sensitive significant differences were detected between the reference sample (diploid scion–diploid rootstock) and the three other combinations. These results suggest that for the profiling of an aromatic flavor, the rootstock is a key element as is the ploidy level of the scion.

Evaluation of a diverse collection of red clover for forage quality and antioxidant activity

Description of the subject. Red clover is an important forage legume and a rich source of high quality forage for livestock feed. This study assesses a diverse red clover collection for agronomic value, forage quality and antioxidant activity in relation to status (cultivar vs natural population) and ploidy level (diploid or tetraploid) for the purpose of diversity study and for identification of potential heterotic groups and classification of accessions according to the results of analyses. Objectives. The aims of this research were to: i) explore agronomic traits, forage quality, and antioxidant activity in relation to status and ploidy level; ii) assess trait associations and the possibility of indirect selection; iii) cluster red clover accessions with regard to forage quality and antioxidant activity. Method. Red clover was represented by 46 accessions, the cultivars and natural populations of diploid (2n) and tetraploid (4n) ploidy levels from 17 countries, which were collected and preserved in the Institute of Field and Vegetable Crops in Novi Sad, Serbia. The following traits were determined from the two-year field trial at Rimski Šančevi, Serbia: plant height (PH), internodes number (IN), green mass yield (GMY), dry matter yield (DMY), crude protein (CP), acid detergent fiber (ADF), neutral detergent fiber (NDF), digestible dry matter (DDM), dry matter intake (DMI), relative feed value (RFV) and antioxidant activity. All accessions were characterized in the second cut of the second year of life when 20-25% of flowers appeared. Results. The cultivars had higher values for PH, IN, GMY, DMY, DDM, DMI, and RFV. The tetraploid accessions had higher values for IN, GMY, DMY, CP, NDF and DDM. The natural populations and diploid accessions had 39.9% and 21.9% smaller antioxidant capacity, respectively. The antioxidant capacity was positively associated with RFV, DDM, DMI, PH, IN, GMY and DMY, but negatively with ADF and NDF. Conclusions. The grouping of red clover accessions based on forage quality parameters and antioxidant activity was represented by five clusters. High-quality cultivars had a shorter length of internodes and a good leaf to stem ratio with a high leaf proportion.

Could the Dilatata group of Paspalum be bred as sexual species? A preliminary assessment

AbstractPaspalum dilatatum Poir. is a perennial apomictic and pentaploid South American grass and a very valued forage crop. The species has been available commercially in several parts of the world; however, its low seed production, apomictic reproduction and ergot susceptibility are important limitations for its adoption and breeding. The Dilatata complex includes five sexual tetraploid mostly selfing species, very closely related to P. dilatatum, which can be hybridized in different combinations. To explore the productive potential of breeding this species group as a sexual selfing tetraploid by combining germplasm from different tetraploid sources, a cross was made between Paspalum flavescens and Paspalum plurinerve which showed high productivity and resistance to ergot. The F1 was compared to the parents and 20 F3 families to evaluate the presence of heterosis, and estimate the additive genetic variance and the degree of transgressive segregation for morphological and productive traits. The F1 showed heterosis for dry matter and the number of fertile tillers, while the F3 showed transgressive segregation in more than 30% of the families for most traits. These results show that hybridization at the tetraploid level can generate vigorous and productive recombinants with a high potential to produce promising transgressive segregants. This breeding strategy appears highly promising, supporting further research on the potential of interspecific hybridization in this group.

Prospects and methods of polyploid selection of new high-yielding miscanthus clones in the natural climatic conditions of Ukraine

Goal. Expanding the breeding trait collection of breeding genotypes of the genus Miscanthus (Anderson) and the genetic basis for new allotriploid clones by transferring components for hybridization of natural wild species Miscanthus sinensis and Miscanthus sacchariflorus to the tetraploid level.
 Methods. Cytological, biotechnological, fluorescent cytphotometry, field, laboratory.
 Results. The efficiency of polyploidisation for induction of new tetraploid forms of miscanthus in liquid nutrient media supplemented with colchicine (0.05% mass) and for stabilization of myxoploid shoots (0.005% mass) for 6 h of cultivation is examined. The period of exposure for Miscanthus sinensis (2x=2x= 38) and Miscanthus sacchariflorus (2x = 2x = 38) varied from 2 hours to 3 days depending on the genetic origin of the material, with transfer to a hormonal environment. The best indicators of tetraploid induction for Miscanthus sinensis were observed for the exposure period of 2 days with polyploidization efficiency (Db%) of 31.25% and 21.42%, and for Miscanthus sacchariflorus 2 and 6 hours with 35.0% and 27.3%, respectively. The technology of transfering rooted shoots into the soil on the Yaltushkiv Eperimental Breeding Farm was improved and the composition of the soil mixture that provided 99% rooting of culture seedlings at a humidity of 60−70% and air temperature of 35−55°С was found.
 Conclusions. New biotechnological tetraploid lines of Miscanthus sinensis (2xn=4x=76) and Miscanthus sacchariflorus (2xn=4x=76) were created in the conditions of liquid nutrient media supplemented with colchicine (0.05 % mass). It is investigated that flowering of new tetraploid clones in the conditions of Ukraine for the second year of vegetation occurs from late September to early October with formation of fertile pollen grains.

The magic of genomics in creating hybrid potato

The magic of genomics in creating hybrid potato

PECULIARITIES OF CREATION OF MISCANTHUS SINENSIS AND MISCANTHUS SACCHARIFLORUS TETRAPLOID LINES

The work aimed at creating tetraploid lines of Miscanthus sinensis and Miscanthus sacchariflorus species. To achieve this goal, we used methods of microclonal propagation, fluorescence cytophotometry, and genomic status differentiation using computer software of AP ‘Partec’ (Germany). It was found that the percentage of cultivated shoots of Miscanthus sacchariflorus for an exposure period of 1 day was 18.86 ± 5.37%. To compare, it was51.78 ± 6.51% in Miscanthus sinensis. The best indicators of tetraploid induction in Miscanthus sinensis were observed for the exposure to colchicine for 2 days with polyploidization efficiency of 31.25% and 21.42%, and in Miscanthus sacchariflorusf or 2 hours and 6 hours with rates of 35.0% and 27.3%, respectively. To stabilize the tetraploid level of genome ploidy, we used Murashige and Skoog liquid media (1962) supplemented with 0.005% colchicine and an exposure period of myxoploids for 6 hours. The flowering of new tetraploid clones in the conditions of Ukraine was observed on the second year of vegetation in late September and the beginning of October with the formation of fertile pollen grains. However, development of a microgametophyte depends on temperature conditions, both for Miscanthus sinensis (4x) and Miscanthus sacchariflorus (4x). Breeding schemes for the formation of anisoploid populations have also been developed: M sinensis (4x) x M sinensis (2x); M. sa?chariflorus (4x) x M sinensis (2x); M sinensis (4x) x M. sachariflorus (2x)

Differential Epigenetic Marks Are Associated with Apospory Expressivity in Diploid Hybrids of Paspalum rufum.

Apomixis seems to emerge from the deregulation of preexisting genes involved in sexuality by genetic and/or epigenetic mechanisms. The trait is associated with polyploidy, but diploid individuals of Paspalum rufum can form aposporous embryo sacs and develop clonal seeds. Moreover, diploid hybrid families presented a wide apospory expressivity variation. To locate methylation changes associated with apomixis expressivity, we compare relative DNA methylation levels, at CG, CHG, and CHH contexts, between full-sib P. rufum diploid genotypes presenting differential apospory expressivity. The survey was performed using a methylation content-sensitive enzyme ddRAD (MCSeEd) strategy on samples at premeiosis/meiosis and postmeiosis stages. Based on the relative methylation level, principal component analysis and heatmaps, clearly discriminate samples with contrasting apospory expressivity. Differential methylated contigs (DMCs) showed 14% of homology to known transcripts of Paspalum notatum reproductive transcriptome, and almost half of them were also differentially expressed between apomictic and sexual samples. DMCs showed homologies to genes involved in flower growth, development, and apomixis. Moreover, a high proportion of DMCs aligned on genomic regions associated with apomixis in Setaria italica. Several stage-specific differential methylated sequences were identified as associated with apospory expressivity, which could guide future functional gene characterization in relation to apomixis success at diploid and tetraploid levels.

Reproductive mode and DNA content of Paspalum accessions from Plicatula group: Reproduction and DNA content of Paspalum

This study aims the reproductive and DNA content characterization of ten different Paspalum species from the Plicatula group (P. atratum, P. compressifolium, P. guenoarum, P. lenticulare, P. lepton, P. oteroi, P. plicatulum, P. rhodopedum, P. rojasii and P. wrightii), contributing to the determination of the best breeding and conservation method to be used. The DNA content of 150 accessions was estimated by flow cytometry using foliar tissues. The reproductive mode of 135 accessions was characterized by flow cytometric seed screening, and five accessions were determined by cytoembryological ovary analysis. DNA content ranged from 1.50 pg (BGP 380) to 4.27 pg (BGP 193), both from P. compressifolium species. Most of the accessions were compatible to the tetraploid level, except for BGP 281 (P. lenticulare), BGP 272 (P. rojasii), and BGP 380 (P. compressifolium), which were diploids. Accessions with tetraploid DNA content presented apomictic reproduction, whereas the three diploid accessions were sexual. These results contribute to the reproductive knowledge of species of the Plicatula group. The diploid sexual accessions identified represent important material to overcome the apomictic barrier in crosses and can be used after polyploidization as female parents in crosses with apomictic accessions in Paspalum breeding programs.

Molecular characterization of Algerian populations of cocksfoot and tall fescue: Ploidy level determination and genetic diversity analysis

AbstractAlgeria is a country rich in phytogenetic resources, especially those of pastoral and forage interest. Unfortunately, few studies have been conducted to characterize Algerian local ecotypes. Recently, advances in next‐generation sequencing technologies have allowed for robust genotyping by sequencing (GBS) for single nucleotide polymorphism (SNP) discovery, making the characterization of plant relationships with complex and unsequenced genomes more feasible. In the present study, we investigate the genetic diversity of cocksfoot and tall fescue ecotypes from different regions in Algeria, using the SNP variation supplied by a GBS analysis. We compared ecotypes to two common cultivars of both species. A total of 787 SNP markers for cocksfoot and 743 for tall fescue were obtained, and the diversity analysis revealed that 88% and 86% of overall variation in cocksfoot and tall fescue, respectively, were within populations rather than among them. Genetic structure analysis revealed a moderate genetic differentiation among accessions with a mean Fst value of 0.127 for cocksfoot and 0.140 for tall fescue, with high gene flow (NmOrchardgrass = 1.723, NmTall fescue = 1.535) and no significant isolation‐by‐distance pattern. A unweighted pair group method with arithmetic mean tree (UPGMA) and principal component analysis revealed the genetic distinctness of populations from cultivars for each species. The flow cytometry analysis confirmed the tetraploid level of cocksfoot and the hexaploid level of all tall fescue entries but one. Although the cocksfoot populations were distinct from the cultivars, the Ruines de djemila population had the broadest base and showed the closest relative relationship to the two cultivars. Similarly, the FE5729 tall fescue population showed the closest relationship to the two tall fescue cultivars.

Metabolomic profiling in evaluation of cultivated oat species with different ploidy level

The article presents biochemical characteristics identified during the analysis of metabolomic profiles. The object of this study was the landraces of cultivated oat species Avena strigosa Schreb., A. abyssinica Hochst. and A. sativa L. with different ploidy levels from the global collection of the Department of Genetic Resources of Oats, Rye, and Barley of VIR. Metabolic profiling was performed using an Agilent 6850 gas chromatograph (Agilent Technologies, USA). The main task of this evaluation was determination of differences between cultivated oat species of diploid, tetraploid and hexaploid ploidy levels according to their metabolomic spectra. These spectra reflect the metabolic state of genotypes of various ecological and geographical origin. The investigation touched on the most important groups of metabolites important for the resistance formation nutritional, medicinal and dietary benefits. Particular, attention was paid to biologically active compounds that determine the functional value of daily human foods − phenolic compounds, free amino acids and sugar acids. The most informative indicators, which separate the oat with different ploidy levels were: isofucosterol, xylitol, MAG-1 18: 0, linolenic, undecylic, threonic, glutamic and methylmalonic acids.