Hybrid Specimens Research Articles

Improving Fire Resistance in E-Vehicles: A Study on MPP-Enhanced S-Glass/Phenolic Hybrid Composites

The automotive industry has benefited greatly from the advancements in fireproof, high-strength fiber-reinforced polymer matrix composites during the last several decades. S-Glass/Phenolic hybrid composites made by hydraulic compression molding are the subject of this investigation into the effects of Melamine Polyphosphate (MPP) on their thermal and fire performance. In addition to studying the morphology of the samples, researchers analyzed the thermal and fire performances of hybrid laminates made with neat laminates and varying compositions of MPP (ranging from 3% to 15% by weight). Tests included UL 94, limiting oxygen index (LOI), and the impacts of accelerated heat ageing on the behavior of the hybrid specimens. The results demonstrated that specimens filled with higher MPP performed better in a fire compared to neat samples. According to the results in UL 94 horizontal burning test and vertical burning test, specimens filled with 12 and 15 wt. % MPP demonstrated a reduced flame spreading rate and fulfilled the V-0 criteria. Simultaneously, the energy absorption capacity of hybrid configurations is severely limited by heat ageing, due to its temperature and duration dependent. The research proved that the suggested S-Glass / Phenolic / Melamine Polyphosphate hybrid composites were suitable for creating environmentally friendly electric vehicle battery housings and fire-resistant automotive parts.

Influence of hydrothermal conditions on the mechanical properties of hybrid composite pipes

Composite materials are becoming widespread in many sectors today, especially in the defence and space industry. Composite materials can be exposed to significant temperature changes and various environmental conditions depending on their usage areas. Therefore, composite materials with high resistance to high temperatures and harsh environmental conditions are being studied today. In this study, four types of 6-layer composite pipes with glass/glass/glass, basalt/basalt/basalt, glass/basalt/glass and basalt/glass/basalt stacking sequences were fabricated with filament wound method. In order to simulate the behavior of composite materials under environmental conditions, specimens were subjected to hydrothermal aging in pure water at 70°C for three different periods of 500, 1000 and 1500 hours. During the aging process, the mass changes of the pipes were measured regularly, and the water absorption behavior was determined with reference to ASTM D5229 standard. Hardness tests were carried out with Rockwell hardness tester based on ASTM D785 standard. As a result of the study, it was determined that the mechanical performance of hybrid specimens was higher than that of non-hybrid specimens. It was observed that the hydrothermal aging process caused a loss of mechanical strength in all specimens. It was concluded that the hybrid composite specimen with basalt/glass/basalt stacking order had the highest resistance to hydrothermal aging.

Fracture toughness analysis of a woven sisal-glass fiber hybrid composite

This experimental work’s goal was to investigate the mode-I fracture toughness behavior of a hybrid composite material made of woven sisal and glass fibers under mode-I loading circumstances to gauge the material’s resistance to fracture behavior. The sisal plant was painstakingly stripped of its fibers. For the sisal fiber surface treatment, 5% NaOH was utilized. Next, treated fibers were weaved by hand to create the woven sisal fiber. Using the hand lay-up technique and the ASTM D5045-99 standard, compact tension specimens were created. The findings indicated that, under mode I loading circumstances, the mode I fracture toughness value of a specimen with a thickness of 5 mm has a (KIC) of 18.34 MPa. m. By determining a material’s resistance to fracture under mode I stress conditions—a condition that is employed in a variety of engineering applications—it is a valuable parameter for developing and establishing preconditions for engineering applications. The manufactured hybrid specimens’ performance and applications for various engineering materials for construction (such as tables, ceilings, and partitions), lightweight vehicle parts (like boards), and replacing synthetic materials with natural fibers in engineering applications were demonstrated by the results of the fracture toughness test.

Testing a set of SSR markers to obtain the genetic profiles of common plum and cherry plum varieties and to assess the genetic similarity between hybrids obtained in remote crossing

Common plum (Prunus domestica L.) is one of the fruit crops that are particularly difficult to study genetically. Unlike most other species of the genus Prunus, it is a hexaploid species (2n=48) originating from complex interspecific hybridization, and the question of its origin is yet to be conclusively resolved. Presently, several studies are available that examine the phylogeny and systematics of the genus Prunus in general and specifically the speciation of Prunus domestica L., with the use of molecular genetics methods. Although the SSR marker method is widely adopted in the practice of studying the most important stone fruit crops, the polymorphism of SSR loci in Prunus domestica L. is rarely studied in the gene pool. The present study examined the effectiveness of 22 microsatellite (SSR) markers using common plum and cherry plum varieties bred at the Federal Horticultural Center for Breeding, Agrotechnology, and Nursery in order to obtain the genetic profiles of these varieties and develop a variety passport. In addition, this set of markers was used to evaluate the genetic diversity and genetic similarity between the varieties of common plum and cherry plum, as well as remote hybrids obtained using embryo rescue, from the collection of the Federal Horticultural Center for Breeding, Agrotechnology, and Nursery. The screening results obtained for a set of 22 SSR markers using 10 varieties and 19 hybrid specimens revealed a low level of polymorphism detected by this set and a small number of shared alleles. This set of markers was found to be inadequate to fully evaluate our sample in terms of allelic diversity, as well as genetic similarity between parental and hybrid forms. The proportion of unique genotypes that can be identified using these markers amounts to less than 50 %. The large number of overlapping fragment sizes prevents the generation of individual genetic profiles for the varieties. It was found necessary to apply and test additional markers, as well as to develop multiplex sets on their basis, which will form the basis for routine genotyping of varieties. For a more accurate and reliable estimation of fragment lengths and allele sharing, further analysis should be performed using capillary electrophoresis. The work was carried out at the Laboratory of Reproductive Biotechnology of the Federal Horticultural Center for Breeding, Agrotechnology and Nursery in 2022.

On Widening the Hybrid Zone for Chars of Genus Salvelinus, Kundscha S. leucomaenis and Northern Dolly Varden S. malma (Salmonidae), in Rivers of Kamchatka Peninsula

The data on widening the zone for hybridization between the chars of the genus Salvelinus, kundscha S. leucomaenis and northern dolly varden S. malma (Salmonidae), in rivers of the Kamchatka Peninsula are reported. If the hybrids between the kundscha and the northern dolly varden could be previously observed only in the Utkholok River in the northwest of the peninsula, the mass hybridization between these species have occurred in two more nearby rivers, the Kvachina and Snatolveem Rivers since 2009. A microsatellite analysis has shown that hybrid specimens are characterized by intermediate values for allelic diversity, when compared to that in the representatives of parental species, while the mean expected heterozygosity values for hybrids are higher than that in Dolly Varden and kundscha fish. The analysis results for maternal inheritance in hybrid specimens from the Kvachina River coincide with that obtained in the surveys previously performed in the Utkholok River. Thus, the same haplotype specific for the kundscha fish was revealed in all the hybrid specimens, which can indicate that the hybrids originate from kundscha females and Dolly Varden males. The appearance and coloration of kundscha × northern dolly varden hybrids in the Kvachina and Snatolveem Rivers are similar to that in the specimens in the Utkholok River. Rather similar chacteristics of hybrid specimens in all three rivers can give reason to consider that a mechanism of their occurrence in the Kvachina and Snatolveem Rivers is simalr to that in the Utkholok River, since the kundscha eggs are inseminated by the Dolly Varden dwarf males. The increased local biological production of rivers due to increased sizes of spawning stocks of pink salmon Oncorhynchus gorbuscha along with large-scale climate changes in the North Pacific are considered as a possible cause of disturbances of isolation between species. It is quite probable that these two factors have contributed to improving the environmental conditions for fattening the Dolly Varden fish in the freshwater phase of their life cycle and, as a resultl of this process, increasing the number of Dolly Varden male fish matuaring in the river.

Lophiolepis (=Cirsium Epitrachys seksiyonu) cinsine ait Türkiye’den yeni bir melez kaydı (Asteraceae, Carduinae)

Lophiolepis Cass., belonging to the tribe Cardueae of the family Asteraceae (subtribe Carduinae) is newly separated from the genus Cirsium Miller in the light of recent molecular studies. It has a high affinity to form interspecific and intersubspecific hybrids under certain circumstances. In the present study, one hybrid combination, Lophiolepis x trifurca (Petr.) Bureš, Del Guacchio, Iamonico &P. Caputo which was previously described as Cirsium x trifurcum Petrak by Petrak in 1914 is newly recorded for Turkish Flora. The hybrid specimens have intermediate characters with parental species; Lophiolepis kosmelii (Adams) Bureš, Del Guacchio, Iamonico & P. Caputo and L. caucasica (Adams) Bureš, Del Guacchio, Iamonico & P. Caputo. Plant samples including parental species were collected from Şavşat district of Artvin province in sympatric populations. These specimens were carefully examined and compared with the putative parents, and morphological character measurements of hybrid plants, as well as parental species were carried out. The samples’ natural habits were photographed, cauline leaf drawings were supplied using a stereomicroscope, leaf micromorphological characters were determined and anatomical characteristics were compared with parents, in detail. In conclusion, intermediate morphological characteristics between L. x trifurca and its parents were determined in terms of features such as cauline leaves, phyllaries, capitula and corolla. It has spines on adaxial sides, and uniseriate multicellular tomentose trichomes in abaxial ones. Cuticle has striate appearance near to the stomata/ trichome bases in the abaxial surface and scale/granules are shown in adaxial parts. This taxon has amphistomatic leaves and dorsiventral mesophyll as in the parental species.

Transferability of the Structure–Property Relationships from Laser-Pretreated Metal–Polymer Joints to Aluminum–CFRP Hybrid Joints

The transferability of structure–property relationships for laser-pretreated metal adhesive joints to laser-pretreated metal–carbon-fiber-reinforced plastic (CFRP) bonds was investigated. Single-lap shear tests were performed on hybrid AW 6082-T6–CFRP specimens pretreated with the same pulsed laser surface parameter sets on the metal surface as previously tested, AW 6082-T6–E320 metal adhesive joints. The fracture surfaces were characterized to determine the type of failure and elucidate differences and commonalities in the link between surface structures and single-lap shear strengths. Digital image analyses of the hybrid specimens’ fractured surfaces were used to quantify remaining CFRP fragments on the metallic joint side. The results indicate that high surface enlargements and the presence of undercut structures lead to single-lap shear strengths exceeding 40 MPa and 35 MPa for unaged and aged hybrid specimens, respectively. Whereas for the metal–polymer joints, the trend from high strength to weakly bonded specimens is largely continuous with the degree of surface structuring, hybrid metal–CFRP joints exhibit a drastic drop in joint performance after aging if the laser-generated surface structures are less pronounced with low surface enlargements and crater depths. Surface features and hydrothermal aging determine whether the specimens fail cohesively or adhesively.

Fabrication, microstructure and mechanical properties of novel titanium and nickel micro-particulates reinforced AZ91D magnesium alloy metal matrix hybrid composites

In the present study, AZ91D magnesium alloy has been successfully produced for the first time by reinforcing with a combination of Ti and Ni microparticles. The manufacture of hybrid composites reinforced with elemental powders at the volumetric proportions of 0–25 % was conducted using the powder metallurgy technique. As a result of optimized fabrication parameters, in all the specimens were nearly obtained full density and a pore-free microstructure. During the morphological examinations were detected α-Mg, β-Mg17Al12, Ti and Ni phases, apart from these, no unwanted secondary phases such as oxide, carbide and nitride were founded. A clean interface formation was observed between the matrix and reinforcement phases in which no chemical reaction occurs. The combined use as reinforcement material of Ti and Ni elements for the first time resulted in approximate ratios of 29 %, 80 % and 30 % significant enhancement in the yield strength, compressive strength and ductility values of the matrix alloy, respectively. Hybrid specimens were determined to have better mechanical properties than those of the unreinforcement matrix alloy at all test temperatures. Produced hybrid composites have been established to be enough to easily meet the temperatures and stresses that automobile components are exposed to under service conditions. In addition, their low-density values of 2.048–3.011 g/cm3 show to compose a significant alternative to conventional materials like iron, steel and even aluminum which are often used in the generation of automobile parts.

Dynamic experimental study of nitinol wire-reinforced composite structures

Due to the advantages of both the metallic and glass fiber qualities, glass fiber reinforced metal layers are one of the best impact resistant materials. Shape memory alloys have also been thought to be effective materials for equipping the traditional impact-exposed materials due to their high impact damping capabilities. The modal response (natural frequencies, damping, and vibration amplitude) of the laminate composite constructions that incorporate shape memory wires was experimentally investigated in this article. The goal of the current research is to ascertain how the modal responses are impacted by three production parameters: wire diameter, wire location, and wire number. Using an experimental design plan and a central composite design, hybrid specimens were planned. The results showed that the manufacturing variables influence all the modal responses in different proportions. Regarding the innovations in the construction of this type of hybrid composite, this study could be used in the design of mechanical and airspace structures.

Adhesion properties of the hybrid system made of laser-structured aluminium EN AW 6082 and CFRP by co-bonding-pressing process

ABSTRACT A parameter investigation for manufacturing a hybrid system through the prepreg pressing process was carried out within the scope of this work to achieve optimal adhesion properties. The hybrid specimen comprises an aluminium sheet of alloy EN AW 6082 in T6 condition and a thermoset Carbon Fibre Reinforced Plastics prepreg. The prepreg pressing process allows the curing reaction of epoxy resin and the joining process to occur simultaneously to avoid an additional bonding process step. The surface of the aluminium sheet was pretreated in advance using a pulsed Nd:YAG laser to enhance the bonding properties. In the first step, the shear edge tests investigated the adhesion properties achieved with different consolidation (temperature, time and pressure) and laser parameters. Then, 3-point bending tests were carried out to investigate the influence of the consolidation parameters on the mechanical properties of the Carbon Fibre Reinforced Plastics-laminate. In this way, the optimal parameter sets for manufacturing hybrid structures were determined.

Stitched Graphene Nanoplatelet Composites for Unitized Aerospace Structures

Lightweight composites play an important role in sustainability as their usage in aerospace vehicles translates to improved fuel consumption and reduced emissions. However, due to their low interlaminar strength, delaminations and microcracking degrade their strength and stiffness properties. Through-thickness stitching in composites enhances interlaminar properties but reduces the in-plane properties. Graphene nanoplatelets (GNPs) and carbon “thin plies” have been found to increase the mechanical properties of these composite structures. This study considers a hybrid composite that uses GNPs coupled with thin plies at the midplane to mitigate the reduction in the in-plane properties. Composite specimens [+45/−45]4s were stitched with two different seam angles (0 and 90°) and tested under uniaxial tensile loading. Surface strain fields from digital image correlation measurements show a significant decrease in strain concentrations in the hybrid specimens compared to the baseline stitched composites. An increase of 17% in tensile modulus and a reduction of 15% in strain energy density are realized due to the hybrid architecture of the stitched composite.

Development and validation of novel SNP markers for the rapid identification of natural hybrids of the 11 closely related pufferfish species (Takifugu spp.) distributed in Japan

Accurate identification of interspecific hybrids is vital for breeding programs in hybridizing taxa, as well as for the use of hybrids in aquaculture and fisheries. The use of species-specific single nucleotide polymorphisms (SNPs) has become the standard for the molecular identification of hybrids. However, it remains challenging to use these SNPs to identify hybrids involving multiple candidate parental species. Here, we developed and validated SNP markers for the identification of hybrids of the 11 closely related pufferfish species (genus Takifugu) distributed in Japan; these species have different aquacultural characteristics, such as growth rate, physiology, behavior, and toxicity. In total, 1232 species-specific SNPs were identified through double-digest restriction-site-associated DNA sequencing. The species had 11 (T. flavipterus) to 295 (T. chrysops) species-specific SNPs. We validated 33 genome-wide species-specific SNPs using TaqMan® genotyping assays for the 11 species and their hybrids, which were identified using amplified fragment length polymorphism analyses. No false negative or positive assignments were observed in 77 and 30 specimens of pure species and F1 hybrids, respectively. This marker combination allows rapid and reliable identification of natural hybrids, which will be useful for pufferfish aquaculture and will enhance our understanding of the natural hybridization between various Takifugu species.

Hybrid reinforcement of steel–polyethylene fibers in cementless ultra-high performance alkali-activated concrete with various silica sand dosages

The effects of steel and polyethylene (PE) fiber hybrid reinforcement on the mechanical performance of cementless ultra-high performance alkali-activated concrete (UHP-AAC) containing an industrial by-product and various amounts of silica sand were investigated. Replacing steel fibers with PE fibers reduced the compressive and tensile strengths, with the best performance was observed in the hybrid specimens with a medium-grade fine aggregate-to-binder (FA/B) ratio. Increasing the PE fiber replacement ratio and decreasing the FA/B ratio increased the occurrence of multiple microcracks. The FA/B ratio had a greater effect on the variation in the pseudo-strain hardening indices than the fiber replacement ratio. The highest complementary energy, 1,762.5 J/m2, was obtained for PE fiber-reinforced UHP-AAC at an FA/B ratio of 0.16, while the lowest value, 309.6 J/m2, was obtained for steel-fiber-reinforced UHP-AAC at the same FA/B ratio. In conclusion, the hybrid reinforcement of UHP-AAC can be optimized by considering the FA/B ratio and fiber replacement ratio.

Experimental and Numerical Investigation of the Mechanical Properties of 3D-Printed Hybrid and Non-Hybrid Composites

Recent research efforts have highlighted the potential of hybrid composites in the context of additive manufacturing. The use of hybrid composites can lead to an enhanced adaptability of the mechanical properties to the specific loading case. Furthermore, the hybridization of multiple fiber materials can result in positive hybrid effects such as increased stiffness or strength. In contrast to the literature, where only the interply and intrayarn approach has been experimentally validated, this study presents a new intraply approach, which is experimentally and numerically investigated. Three different types of tensile specimens were tested. The non-hybrid tensile specimens were reinforced with contour-based fiber strands of carbon and glass. In addition, hybrid tensile specimens were manufactured using an intraply approach with alternating carbon and glass fiber strands in a layer plane. In addition to experimental testing, a finite element model was developed to better understand the failure modes of the hybrid and non-hybrid specimens. The failure was estimated using the Hashin and Tsai-Wu failure criteria. The specimens showed similar strengths but greatly different stiffnesses based on the experimental results. The hybrid specimens demonstrated a significant positive hybrid effect in terms of stiffness. Using FEA, the failure load and fracture locations of the specimens were determined with good accuracy. Microstructural investigations of the fracture surfaces showed notable evidence of delamination between the different fiber strands of the hybrid specimens. In addition to delamination, strong debonding was particularly evident in all specimen types.

Experimental Investigation of Effect of L-Profile Hybrid Aluminium/GFRP to the Axial and Lateral Characteristic.

The current study investigates the effect of a hybrid L-profile aluminium/glass-fiber-reinforced polymer stacking sequence under axial and lateral compression loads. Four stacking sequences are studied: aluminium (A)-glass-fiber (GF)-AGF, GFA, GFAGF, and AGFA. In the axial compression test, the aluminium/GFRP hybrid tends to crush in a more progressive and stable failure than the net aluminium and net GFRP specimens, with a relatively more stable load-carrying capacity throughout the experimental tests. The AGF stacking sequence was second, with an energy absorption of 145.31 kJ, following AGFA at 157.19 kJ. The load-carrying capacity of AGFA was the highest, with an average peak crushing force of 24.59 kN. The second-highest peak crushing force, 14.94 kN, was achieved by GFAGF. The highest amount of energy absorption, 157.19 J, was achieved by the AGFA specimen. The lateral compression test showed a significant increase in load-carrying and energy absorption capacity in the aluminium/GFRP hybrid specimens compared to the net GFRP specimens. AGF had the highest energy absorption with 10.41 J, followed by AGFA with 9.49 J. AGF also had the highest peak crushing force with 2.98 kN, followed by AGFA with 2.16 kN. The most crashworthy stacking sequence among the four variations tested in this experimental research was the AGF stacking sequence because of its great load-carrying capacity, energy absorption, and specific energy absorption in axial and lateral loading. The study provides greater insight into the failure of hybrid composite laminates under lateral and axial compression.

Seismic Analysis of Posttensioned and Hybrid Bridge Bents with Buckling Restrained Braces

A numerical model is presented for a rocking bridge bent specimen consisting of two precast concrete columns with posttensioning (PT) bars, two footings, and a cap beam, with or without a buckling restrained brace (BRB). First, a numerical model of the posttensioned bridge bent specimen without a BRB is developed; emphasis is placed on modeling the rocking mechanism at the joint between precast concrete members joined only through PT bars. The numerical model is extended to a hybrid specimen consisting of a two-column posttensioned bridge bent with a BRB as an external energy dissipation device. Experimental results obtained from quasi-static cyclic tests of the posttensioned and hybrid specimens are compared with the numerical models. Satisfactory agreement of the numerical models with the experimental results is observed in terms of structural response, hysteretic energy, and PT-bar forces. The numerical models are subsequently extended to a previously tested three-column bridge bent for two configurations: (1) a posttensioned bridge bent with PT bars, and (2) a hybrid bridge bent with PT bars and two BRBs. A fiber-based bridge bent model is built, which includes soil–structure interaction (SSI) using simplified springs. A comparison of the posttensioned and hybrid bridge bents using far-field and near-field ground motions shows that the hybrid bridge bent displays superior performance compared with the posttensioned-only bridge bent.

An evaluation of elution of leachable components from composite resins after light curing by light emitting diode and halogen light: An in vitro study.

The purpose of our study was to determine the amount of eluted triethyleneglycol dimethacrylate (TEGDMA) and to compare the eluted TEGDMA in different composite resins after light curing with conventional halogen light curing unit and light emitting diode (LED). The present study was conducted on the two types of composite resins, which were divided equally into four groups - Group I: Denoted as Hybrid-LED, Group II: Denoted as Microhybrid-LED, Group III: Denoted as Hybrid-Halogen Group IV: Denoted as Microhybrid-Halogen. Polymerized specimens of hybrid and microhybrid composite resins were stored in air tight centrifuge tubes at 37°C for 24 h, then extract the monomers in high-performance liquid chromatography (HPLC) grade acetonitrile and water and incubated at 37°C for 24 h. All extracts were analyzed by HPLC. Eluted TEGDMA was detected by ultraviolet detector. The results obtained for TEGDMA were computed and analyzed using the one-way ANOVA and independent samples F-test at significance level 0.05. Elution of TEGDMA from all the samples of Group III (Hybrid-Halogen) was greatest and from Group II (Microhybrid-LED) was lowest. The sequence of TEGDMA elution was Group III > Group I > Group IV > Group II. From our results, we can conclude that the LED light curing unit may be more efficient than standard halogen light curing unit. The extractable quantities of composite resin components should be minimized. Furthermore, all ingredients of a dental composite should be declared by the manufacturers, in order to identify those substances in a product which may cause adverse side effects in patients and dental personnel.

Open hole tensile behavior of plain woven carbon/glass hybrid composites

Hybrid composites are increasingly attractive for advanced engineering applications. In this study, the open-hole tensile (OHT) properties and failure mechanism of plain woven carbon fiber, glass fiber, and carbon/glass hybrid fiber composites under on-axis (0°) and off-axis (45°) loads were investigated through experimental and numerical approaches. The progressive damage was characterized by high-speed infrared thermography. The numerical simulation presented a good explanation on the damage development. It indicates that the carbon/glass hybrid composites exhibited significant improvement in failure strain and toughness compared to pure carbon fiber composite. With the insertion of glass fiber layers, the failure modes of hybrid structures were modified and quick propagation of cracks was prevented. Once the cracking on their carbon layers had initiated there was an increase in damage to glass fiber layers showing the transfer of stress from carbon layers to glass layers. Similar mechanical properties were reached among sandwich-like hybrid samples in on-axis tension, but much greater properties can be achieved when the carbon fiber at the interior layers of the hybrid specimens under off-axis load. Since glass fiber with great ductility was laminated as the surface layers in hybridization, resulting in less delamination and higher ultimate strength in 45○ off-axis tension.

Hybrid Curved Precast Deep Beams Composed Partially from Concrete Made with Recycled Concrete Aggregate

The present work presents the results of the experimental investigation of using crushed concrete as recycled coarse aggregates (RCA) and new models of hybrid deep beams. Six specimens of deep beams have been tested under static loads: two specimens as controls and three hybrid specimens with different types of hybridization models for concrete sections (horizontal, curved, and arched). This study aims to search for the optimum distribution of the concrete types for the hybrid deep beams such that the lowest cost is obtained and the RCA obtained from building demolition waste is introduced into the concrete mixes at 100%. The behavior has been tracked by the cracking and failure loads, loading history, crack width, and toughness. It was found that the capacities increased by 7.7, 18.7, 17.2, and 28.2%, respectively, in the horizontal, curved, arched, and arched with inclined stirrups hybrid models compared to the control specimen with RCA. Moreover, toughness was enhanced for the same specimens by 50.9, 71.1, 100.5, and 144.6%, respectively, compared to the control specimen with RCA.

Chloroplast genomes of Vitis sp. samples from Nechaevsk population of the Krasnodar region

The presented study demonstrates the results of sequencing and analysis of wild grape plastomes assemblies located in the Nechaevsk population. Previously, the habitats of the wild forest grape V. vinifera subsp. silvestris were explored as an outcome of expeditions. As a result of repeated expeditions, samples were taken and used to isolate chloroplast DNA. Assembly and annotation of plastomes showed the presence of DNA encoding sequences. At the same time, the structure of the obtained plastomes varied. These expressed in the presence of DNA polymorphisms. Comparison of the aligned sequences made it possible to reveal the presence of the species V. vinifera subsp. sylvestris in the population, as well as hybrid specimens. This is also confirmed by the result of determining the taxonomy after depositing the archives of readings in the NCBI database.