Allele Pool Research Articles

Biodiversity and functional variability of the allele pool of horse breed populations

Polysaccharide storage myopathy (PSSM1) is a disease of excessive accumulation of glycogen in muscles, which is encoded by the enzyme glycogen synthase (GYS1). The horses with a mutation at the locus (GYS1) have substandard performance, they often experience muscle pain with intense work, get sweaty and have stiffness in movement, which is generally accompanied by a decrease in performance. The aim of our research was to study the GYS1 mutation (g.18940324 G> A) in glycogen accumulation in horses of different breeds. For the study, horses (n = 181) of ten factory and local breeds were selected, including Russian Donskaya, Bashkirskaya, Buryatskaya, Vladimirskaya, Vyatskaya, Percheronskaya, Russian heavy draft, Soviet heavy draft, Orlov trotter and Thoroughbred horse breeds. According to the results of testing, the GYS1 mutation was found in Bashkirskaya horse breed (3.2%), Buryatskaya horse breed (10%), Vyatskaya horse breed (9.5%), Soviet heavy draft horse breed (30%), Russian heavy draft horse breed (49.9%) and Percheronskaya horse breed (90%). Donskaya, Thoroughbred and Orlov trotter horse breeds showed no PSSM1 defect. Timely diagnostics and monitoring of horse breeds for the presence of genetic abnormalities that reduce their health and performance allow avoiding the accumulation of genetic burden in populations and contribute to increasing the efficiency of breeding programs.

Comparative Study of the Genetic Diversity of Local Steppe Cattle Breeds from Russia, Kazakhstan and Kyrgyzstan by Microsatellite Analysis of Museum and Modern Samples

The comparative molecular genetic study of museum and modern representatives of cattle breeds can help to elucidate the origin and maintenance of historical genetic components in modern populations. We generated the consensus genotypes for 11 microsatellite loci for 24 museum samples of Kalmyk, Kyrgyz, and Kazakh cattle, dated from the first quarter of the 20th century, and compared them with those of modern Kalmyk, Kyrgyz, and Kazakh white-headed breeds. The level of genetic diversity of the modern Kalmyk and Kyrgyz cattle (uHe = 0.771–0.778) was similar to those observed in the museum samples (uHe = 0.772–0.776), while a visible decrease in genetic variability in the modern Kazakh white-headed breed compared to museum Kazakh cattle was detected (uHe = 0.726 and 0.767, respectively). The PCA plot, FST- and Jost’s D-based networks, and STRUCTURE clustering provided strong evidence of the maintenance of the historical genetic background in modern populations of Kalmyk and Kyrgyz cattle. In spite of the allele pool of Kazakh white-headed cattle having undergone great changes compared to the museum Kazakh cattle, several animals still carry the visible aspect of the historical genetic components. Our results can be used for the selection of individuals for the creation of gene banks and may significantly improve the efficiency of conservation programs aimed at preserving genetic diversity in the national genetic resources of cattle.

Introduction of wild Chinese gorals into a captive population requires careful genetic breeding plan monitoring for successful long-term conservation

The Chinese goral (Naemorhedus griseus) is a small goat-like animal, which is considered “vulnerable” due to its rapid decline in population in the wild. Captive breeding programs are necessary to prevent the extinction of Chinese gorals; however, reproduction in captivity reduces genetic diversity due to inbreeding. In 2020, a total of six wild Chinese gorals were introduced into a captive population of 73 individuals to improve the allelic gene pool. An assessment of captive gorals was conducted to trace and understand genetic diversity in the new captive state. Microsatellite genotyping and mitochondrial D-loop sequence analyses were performed to examine the genetic diversity and population structure. The results showed very low haplotype diversity, with a significant difference between He (0.477 ± 0.065) and Ho (0.196 ± 0.056), suggesting a high degree of inbreeding. This resulted in a limited ability to adapt to environmental change and low natural reproductive fitness, thus increasing the risk of population decline and eventual extinction. Management of captive breeding plans based on different subpopulations and haplotypes has been proposed to maximize genetic variability and enhance the success of future conservation plans.

The study of genetic distinctions of brown Swiss cattle breed with using STR-markers

The study of allele pool condition and genetic diversity of Brown Swiss cattle breed was conducted with using STR-markers. Sample collection included samples (n=347) of five breeds: Russian selection Brown Swiss (BSH1), German selection Brown Swiss (BSH2), Jersey (DJ), Simmental (SIM), Kostromskaya(KOS) and Holstein (HOLSH). Polymorphism of 11 microsatellite loci was studied on 16-channell genetic analyzer ABI3130xl. A total of 393 allales with minimal number in DJ group (54) and maximal in SIM group (84) were founded. The number of alleles per locus ranged from 25 (BM1824) to 50 (TGLA122) and average number of alleles per locus ranged from 4.33 (TGLA126) to 8.33 (TGLA122) with a mean of 5.95. Effective number of alleles per locus varied from 2.88 (DJ) to 3.76 (BSH2). Maximal (4.64) and minimal (3.73) numbers of informative alleles were found in BSH2 and BSH1 groups, respectively. Observed heterozygosity range exceeded 0.70 in all groups, except DJ. A total of 23 private alleles were detected ranged from 0,005 (SIM) to 0,385 (DJ). AMOVA analysis showed that 80.068% of variation was observed within populations while 5.186% of variability was intergroup differences. The population structure analysis showed a high level of belonging of all groups to their own cluster. The FCA method revealed an overlapping of multilocus genotypes of BSH1, BSH2 иKOS groups. The results we obtained reveal a high level of genetic diversity in Russian population of Brown Swiss cattle breed.

Genetic architecture of wild soybean (Glycine soja Sieb. and Zucc.) populations originating from different East Asian regions

East Asian region is home to wild soybean and has high topographic complexity. Measuring genetic diversity and geographical distribution patterns are essential steps to expand the germplasm base. We used SoySNP6K to determine the genetic diversity and population genetic structure of the wild soybean populations from four East-Asian geographies i.e. China, Japan, Korea, and Russian Far East. The wild soybean populations from China, Japan, and Korea are distinct from one another based on genetic structure, whereas the one from Russian Far East was not distinguishable from the Chinese wild soybeans. These populations share three ancestral populations and have a large number of common SNPs. Despite the low genetic diversity scores between the populations, the Chinese accessions had the highest genetic diversity values while the accession from Russian Far East had the lowest. Our analysis also showed that the population is showing a departure from the Hardy–Weinberg equilibrium and there is a possibility of inbreeding for most of the loci. The results showed that the genetic variation follows the geographic distribution within each geographically distinct wild soybeans population. Therefore, a diverse collection of wild soybeans representing all-natural habitats should include representatives from each of these sub-centers. This population would provide important breeding materials to expand the allelic pool of cultivated soybeans through introgression. Based on these criteria, the Chung’s wild legume germplasm collection from Korea provides a good representation of the genetic diversity in wild soybeans for use in soybean breeding programs.

Алельний поліморфізм мікросателітних локусів ДНК яєчних курей

The analysis of allelic polymorphism of five industrial egg crosses of chickens by five microsatellite DNA loci (ADL0268, MCW216, LEI0094, ADL0278, and MCW248) was carried out. DNA loci were chosen according to the recommendations of the International Society for Animal Genetics (ISAG). Based on the results of mathematical-statistical processing and data analysis, the spectra and frequencies of allelic variability, the peculiarities of allele pools, were identified, and unique alleles were identified. In general, the species Gallus gallus is characterized by a specific character of allelic spectra for all investigated microsatellite DNA loci (P <0.001). The highest rates of allelic variability were recorded in brown crosses "Lohmann brown" and "Hisex brown" (Na (LimNa)=(9.2 (5-17) and 7.4 (6-11), respectively). The studied crosses were characterized by a shift in allelic spectra towards a decrease in the fragment length. “Lohmann white” stands out among the birds of other crosses by high consolidation for individual alleles for all studied microsatellites (from ADL278114 – 0.343 and ADL268108 – 0.485 to LEI094259 – 0.720, MCW0248213 – 0.785 and MCW0216137 – 0.920). Unique alleles with the highest frequency were found in brown cross chickens, and in the “Hy-Line W-98” bird, they were not found. The number of unique alleles identified varied from 1 ("Hisex white") to 11 ("Lohmann brown"). Locus LEI094 turned out to be the most polymorphic in terms of the number of unique alleles – 10 such allelic variants were identified for it. No unique alleles were identified at the ADL0268 locus. The obtained estimates criterion χ2 of K. Pearson indicate significant differences in the frequency distribution of alleles for all studied loci. When using the MICROSATELLITE ANALYSER software, it was found that the nature of the variability of the studied microsatellite DNA loci in five industrial crosses of the egg chickens, both in the number of identified alleles and in the nature of their distribution, corresponded to the stepwise mutation model (SMM).

The Evolutionary Genomics of Serpentine Adaptation.

Serpentine barrens are among the most challenging settings for plant life. Representing a perfect storm of hazards, serpentines consist of broadly skewed elemental profiles, including abundant toxic metals and low nutrient contents on drought-prone, patchily distributed substrates. Accordingly, plants that can tolerate the challenges of serpentine have fascinated biologists for decades, yielding important insights into adaptation to novel ecologies through physiological change. Here we highlight recent progress from studies which demonstrate the power of serpentine as a model for the genomics of adaptation. Given the moderate – but still tractable – complexity presented by the mix of hazards on serpentine, these venues are well-suited for the experimental inquiry of adaptation both in natural and manipulated conditions. Moreover, the island-like distribution of serpentines across landscapes provides abundant natural replicates, offering power to evolutionary genomic inference. Exciting recent insights into the genomic basis of serpentine adaptation point to a partly shared basis that involves sampling from common allele pools available from retained ancestral polymorphism or via gene flow. However, a lack of integrated studies deconstructing complex adaptations and linking candidate alleles with fitness consequences leaves room for much deeper exploration. Thus, we still seek the crucial direct link between the phenotypic effect of candidate alleles and their measured adaptive value – a prize that is exceedingly rare to achieve in any study of adaptation. We expect that closing this gap is not far off using the promising model systems described here.

State and ways of purposeful conservation of gray Ukrainian breed and its use in the future breed formation process

The study of the gene pool of gray Ukrainian cattle on the basis of the State Enterprise “Polivanovka” was carried out in 2018–2020. They relied on retrospective and modern analysis of the population, using genetic, immunogenetic, breeding, zootechnical, statistical and biometric methods. The animals of this herd belong to two lines: Petushok 191U (62 %) and Shamrin XU-41 (38 %) and 20 families. They have a sturdy, dense and rough type of constitution. Average somatometric indicators correspond to the standard. The breed has good slaughter performance and beef properties. Slaughter yield in bulls reaches 58–59 %, fat – 2.5–3 %, protein: fat ratio – 1: 1.5, pulp in the carcass – 72–73 %, bones – 16–17 %, meat index – 4, 4–4.5. Animals with a high coefficient of inheritance pass on to their descendants specific breed characteristics (color, shape of horns, physique, acclimatization to various natural zones, adaptation to feeding conditions, increased resistance, small fruit size, long growth, stress resistance). The use of modern techniques made it possible to test erythrocyte antigens, serum proteins, isozyme erythrocytes and tissues, as well as polymorphism, the length of restriction DNA fragments. Of the 49 antigens of blood groups, 48 were found. There was a high frequency of them (45–92 %) A, G3, C1, C2, R2, W, X1, X2, E, F, Y, J, H1, Z and much lower ( 2–10 %) P1, P2, B1, J2, P1, R, C1, L, H2. Over the past 30 years, the number of alleles of the most informational system B has decreased from 41 to 14, among them breed-specific B, B2, G3, J1, Q, T1, G2, K, V, E, O. The narrowing of the allelic pool to this level indicates that the breed is on the verge of extinction. Analysis of biochemical markers of blood serum proteins albumin and post-albumin was found in three phenotypes AA, BB, and AB, post-transformation – also in three phenotypes FF, FS, and SS. In terms of hemoglobin, all studied animals of the herd are of type A. Restriction analysis of mitochondrial DNA revealed polymorphism only for endonuclease Eco 471. Modern selection and genetic methods are able to maintain and preserve the specific properties of the breed, its structure, and genetic variability. Their use in combination with technological methods helps to prevent the disappearance of livestock and provide it with a worthy place in the world heritage of genetic resources. Our proposals are summarized in the "Concept of purposeful conservation of gray Ukrainian cattle and their use in the further breed-forming process." Key words: cattle, gray Ukrainian breed, condition, direction of use, offers.

Genetic Evaluation of the Breeds of Reindeer (Rangifer tarandus) and Their Wild Ancestor Using a New Panel of STR Markers

To study the genetic differentiation and phylogeny of the breeds and populations of reindeer (Rangifer tarandus L.), a test system based on multiplex PCR analysis of 16 highly polymorphic STR markers (Rt6, BMS1788, Rt30, Rt1, Rt9, FCB193, Rt7, BMS745, С143, Rt24, OheQ, С217, С32, NVHRT16, T40 and C276) was developed. Using this test system, 397 animals from 11 samples were studied. Four of these samples belonged to the wild forms of reindeer, while the rest of the samples represented the Nenets, Even, and Evenk breeds reared in different climatic zones of the Russian Federation. For 16 microsatellite loci, 204 alleles were identified, some of which could be considered breed-specific. It was demonstrated that more than 70% of the unique allele pool was concentrated in wild populations of reindeer. Statistical analysis of microsatellite data showed that the developed test system was an effective tool for identifying domesticated and wild forms of reindeer, testing the breed assignment, and determining the migration flows of a species over the vast territory of its distribution.

42 Genetic differentiation of Russian goats and wild relatives based on microsatellite loci

Abstract Goat breeding is a traditional livestock industry for many regions of Russia. Due to unpretentiousness and high adaptive qualities, the Karachai, Dagestan wool and Dagestan down breeds are widespread in the North Caucasus. Moreover, their uniqueness is determined by sharing a common habitat with their wild relatives, West Caucasian and Dagestani turs, thus forming hybrid zones. The aim of the research was to study allele pool and interbreed differentiation of domestic goat breeds and wild relatives by microsatellites. Research was performed based on 16 loci on the ABI 3130xl analyzer. Population genetic characteristics were calculated in GenAlEx 6.5, and the phylogenetic tree was constructed in Populations 1.2.30 and SplitsTree 4.14.5. The sample collection included goat breeds (n = 226): Karachai (KRCH), Dagestan down (DAGD), Dagestan wool (DAGW) (North Caucasus), Soviet wool (SOVW) (Siberia), Orenburg (OREN) (South Ural), and wild goats (n = 72). Wild goats comprised mountain goats: Siberian goats (Capra sibirica) from the Altai, Tajikistan, Kyrgyzstan and the Himalayas; bezoar goats (Capra aegagrus) from Turkey and Pakistan; and tur (Capra caucasica) from the West Caucasus (Kuban), Central Caucasus, and East Caucasus (Dagestan). The Karachai breed was characterized by the highest level of genetic diversity: the average number of alleles per locus (NA) and allelic richness (AR) were 9,154 and 7,713, respectively, while these indices varied from 6,538 to 7,538 and from 6,425 to 7,538 (Table 1) in other breeds, respectively. The values of genetic distances showed differentiation of Karachai, Dagestan down and Dagestan wool breeds from Orenburg and Soviet wool breeds (Table 2). The formation of three clusters was established. The first one included subspecies of the Caucasian tur, the second one comprised Siberian goats, and the third contained domestic goats. Bezoar goats were in the root of the third cluster that confirmed their participation as an ancestral form of domestic goats.

The pattern of genetic diversity of different breeds of pigs based on microsatellite analysis.

One of the main tasks of genetics and animal breeding is the assessment of genetic diversity and the study of genetic relationships between different breeds and populations using molecular genetic analysis methods. We analysed the polymorphism of microsatellites and the information on the state of genetic diversity and the population structure of local breeds in Russia: the Kemerovo, the Berkshire, the Liven, the Mangalitsa, and the Civilian; in the Republic of Belarus: the Large White and the Black-and-White; and in Ukraine: the White Steppe, as well as commercial breeds of imported origin of domestic reproduction: the Large White, the Landrace, and the Duroc. The materials used for this study were the tissue and DNA samples extracted from 1,194 pigs and DNA of the UNU “Genetic material bank of domestic and wild animal species and birds” of the L.K. Ernst Federal Research Center for Animal Husbandry. Polymorphisms of 10 microsatellites (S0155, S0355, S0386, SW24, SO005, SW72, SW951, S0101, SW240, and SW857) were determined according to the previously developed technique using DNA analyser ABI3130xl. To estimate the allele pool of each population, the average number of alleles (NA), the effective number of alleles (NE ) based on the locus, the rarified allelic richness (AR), the observed (HO ) and expected (HE ) heterozygosity, and the fixation index (FIS) were calculated. The degree of genetic differentiation of the breeds was assessed based on the pairwise values of FST and D. The analysis of the allelic and genetic diversity parameters of the local breeds showed that the maximum and minimum levels of polymorphism were observed in pigs of the Ukrainian White Steppe breed (NA = 6.500, NE = 3.709, and AR = 6.020) and in pigs of the Duroc breed (NA = 4.875, NE = 2.119, and AR = 3.821), respectively. The highest level of genetic diversity was found in the Large White breed of the Republic of Belarus (HO = 0.707 and NE = 0.702). The minimum level of genetic diversity was found in pigs of the imported breeds – the Landrace (HO = 0.459, HE = 0.400) and the Duroc (HO = 0.480, HE = 0.469) – indicating a high selection pressure in these breeds. Based on the results of phylogenetic analysis, the genetic origin of Large White pigs, the breeds, from which the Berkshire pigs originated, and the genetic detachment of the Landrace from the Mangalitsa breeds were revealed. The cluster analysis showed a genetic consolidation of the Black-and-White, the Berkshire, and the Mangalitsa pigs. Additionally, the imported breeds with clustering depending on the origin were characterised by a genetic structure different from that of the other breeds. The information obtained from these studies can serve as a guide for the management and breeding strategies of the pig breeds studied, to allow their better use and conservation.

Phenylketonuria in the Latvian population: Molecular basis, phenylalanine levels, and patient compliance

IntroductionPhenylketonuria (PKU) is an inborn error of metabolism characterized by pathogenic variants of the phenylalanine hydroxylase (PAH) gene with a resulting accumulation of phenylalanine (Phe) to neurotoxic levels. Diagnosis of PKU in the Latvian population began in 1985 and the present study's aim was to evaluate the available data on all PKU patients in Latvia. Materials and methodsThe medical records of 116 - DNA sample was available in 110 patients (102 nonrelated individuals) diagnosed with PKU in Latvia were obtained. Phe concentrations were measured in dried blood spots. Genomic DNA was analyzed for pathogenic variants in the PAH gene. Biochemical data were available through follow-up visits of the 83 patients. ResultsIn 97% of patients (99 of 102), pathogenic variants were detected on both alleles. With an occurrence of 69.6%%, the most common pathogenic variant was the severe pathogenic variant p.Arg408Trp. The available data for 83 patients revealed that metabolic control was better in younger age groups and worse in adults. ConclusionLatvia exhibits a relatively homogeneous pool of disease-causing PKU alleles with a high prevalence of the classical severe form of PKU. Dietary compliance in all patients' groups is lower than expected, especially it is poor in adult age group.

Characteristics of allele pool of cattle of simmental breed in Kazakhstan

One of the key aspects of studying of new breeds, types and lines of farm animals is to evoluation the state of their allele pool by using DNA markers. At the same time, it should be noted that a significant contribution to the characteristic of allelic diversity of breeds is made by regional populations, the formation of which in most cases took place on the basis of local cattle, which are carriers of their own unique allele pool. It is known that studies on microsatellites make it possible to determine the genetic diversity within and between breeds, and the average number of alleles, observed and expected heterozygosity, allow us to calculate the genetic parameters of populations and evaluate their diversity. The purpose of the research was to study the features of the allele pool of a new intra-breed type Ertis of Red-and-White dairy cattle in the Simmental breed. The sampling of biological materials has been carried out according to generally accepted methods. Genotyping has been performed with a set of StockMarks Cattle at 12 loci. Identification of amplification products has been performed on the abi Prism 310 genetic analyzer (Applied Biosystems, USA) using capillary electrophoresis. Decoding of the obtained graphical results has been carried out in the program GeneMapper 4,0. The results of researches on the genetic structure of the studied population of cattle have been reflected in the article. It has been found that there are 65 alleles in 12 loci of the microsatellite, of which 7 alleles with a frequency of occurrence of ≤1 % have been identified. The most informative loci were TGLA227, TGLA122, ETH3, and TGLA53. The average level of expected heterozygosity was 0,68, with random inbreeding – 0,0488. Studies of the genetic profile of the new intra-breed type of dairy cattle Ertis allowed us to establish the wide variety of allele pool in it, and the small number of rare alleles allocated gives grounds for the possibility of determining this population as an independent structural unit in Simmental breed.

Genetic parameters of the Chukchi breed populations in generational change

The purpose of the work is to study the genetic characteristics of reindeer populations in the Chukotka Autonomous Region using DNA microsatellites. Genetic monitoring data for 2013 and 2018 are presented (the interval of one generation). In the genetic parameters of populations statistically significant differences were found. Samples are characterized by a large number of active alleles of breed diversity. The average number of alleles per locus ranged from 7.7 to 9.95. Indices of heterozygosity in the studied groups of deer are from 0.851 to 0.887 - indicate the prosperous condition of the populations of the Chukchi breed by genetic heterogeneity. The differentiation of livestock is influenced by inter-farm and inter-herd exchange of the allele pool. Criteria for the genetic similarity of the selective sample populations of 2013 and 2018 according to the frequencies of the ISSR markers were in the range from 0.852 to 0.993, which indicates the stability of the gene pools of the studied deer groups. Eco-geographical and economic conditions affect the frequency of ISSR markers with a force of ηx2 = 67-70.4%, being the main factor of intraspecific differentiation. According to the identified microsatellite loci, the populations of the Chukchi breed are in a state of genetic equilibrium. Factors which stabilize the genetic structure of the populations of the Chukchi breed are free crosses typical for reindeer, a large number of males involved in reproduction. Noting that the number of deer of the Chukchi breed is declining, constant monitoring of its gene pool is necessary, which provides the stability of populations.

Intraspecific genetic variation of a Fagus sylvatica population in a temperate forest derived from airborne imaging spectroscopy time series.

The growing pace of environmental change has increased the need for large‐scale monitoring of biodiversity. Declining intraspecific genetic variation is likely a critical factor in biodiversity loss, but is especially difficult to monitor: assessments of genetic variation are commonly based on measuring allele pools, which requires sampling of individuals and extensive sample processing, limiting spatial coverage. Alternatively, imaging spectroscopy data from remote platforms may hold the potential to reveal genetic structure of populations. In this study, we investigated how differences detected in an airborne imaging spectroscopy time series correspond to genetic variation within a population of Fagus sylvatica under natural conditions.We used multi‐annual APEX (Airborne Prism Experiment) imaging spectrometer data from a temperate forest located in the Swiss midlands (Laegern, 47°28'N, 8°21'E), along with microsatellite data from F. sylvatica individuals collected at the site. We identified variation in foliar reflectance independent of annual and seasonal changes which we hypothesize is more likely to correspond to stable genetic differences. We established a direct connection between the spectroscopy and genetics data by using partial least squares (PLS) regression to predict the probability of belonging to a genetic cluster from spectral data.We achieved the best genetic structure prediction by using derivatives of reflectance and a subset of wavebands rather than full‐analyzed spectra. Our model indicates that spectral regions related to leaf water content, phenols, pigments, and wax composition contribute most to the ability of this approach to predict genetic structure of F. sylvatica population in natural conditions.This study advances the use of airborne imaging spectroscopy to assess tree genetic diversity at canopy level under natural conditions, which could overcome current spatiotemporal limitations on monitoring, understanding, and preventing genetic biodiversity loss imposed by requirements for extensive in situ sampling.

Genomic characterization of Ugandan smallholder farmer-preferred cassava varieties.

Understanding the genetic relationships among farmer‐preferred cassava (Manihot esculenta Crantz) varieties is indispensable to genetic improvement efforts. In this study, we present a genetic analysis of 547 samples of cassava grown by 192 smallholder farmers, which were sampled at random within four districts in Uganda. We genotyped these samples at 287,952 single nucleotide polymorphisms using genotyping‐by‐sequencing and co‐analyzed them with 349 cassava samples from the national breeding program in Uganda. The samples collected from smallholders consisted of 86 genetically unique varieties, as assessed using a genetic distance‐based approach. Of these varieties, most were cultivated in only one district (30 in Kibaale, 19 in Masindi, 14 in Arua, and three in Apac), and only three were cultivated across all districts. The genetic differentiation we observed among farming districts in Uganda (mean fixation index [F ST] = .003) is similar to divergence observed within other countries. Despite the fact that none of the breeding lines were directly observed in farmer fields, genetic divergence between the populations was low (F ST = .020). Interestingly, we detected the presence of introgressions from the wild relative M. glaziovii Müll. Arg. on chromosomes 1 and 4, which implies ancestry with cassava breeding lines. Given the apparently similar pool of alleles in the breeding germplasm, it is likely that breeders have the raw genetic material they require to match the farmer‐preferred trait combinations necessary for adoption. Our study highlights the importance of understanding the genetic makeup of cassava currently grown by smallholder farmers and relative to that of plant breeding germplasm.

Comparative Genetic Characteristics of the Russian and Belarusian Populations of Wisent (Bison bonasus), North American Bison (Bison bison) and Cattle (Bos taurus)

A comparative study of the allele pool and the genetic structure of two Russian and one Belarusian populations of the wisent Bison bonasus against the representatives of the species of Bison bison and the genus Bos taurus was carried out. Russian populations were represented by samples of the Oka State Natural Biosphere Reserve (n = 42) and the Prioksko-Terrasny Nature Biosphere Reserve (n = 69), the Belarusian population was represented by samples of the Reserve “Belovezhskaya Pushcha” (n = 42), bison samples (n = 8) and cattle (n = 55) were used as an outgroup. The analysis of the mtDNA D-loop 630 bp fragment polymorphism for the presence of bison and cattle haplotypes, was performed. It was shown that there was a single haplotype for all wisent (Bison bonasus) which was different from the sequences of bison (Bison bison) and cattle. The analysis of population genetic parameters, calculated using 11 microsatellite markers, showed reduced diversity in wisent (Bison bonasus) groups compared to bison (Bison bison) and cattle. The largest number of monomorphic loci as well as the absence of private alleles were found in the group of Belarusian wisent. The analysis of the DJost pairwise genetic distances allowed us to establish clear genetic differentiation of the wisent from the outgroups. This fact was also confirmed by PCA analysis, carried out in the context of population identity and the analysis of population structure which demonstrated some proximity of bison (Bison bison) to wisent (Bison bonasus), which is due to their belonging to the same genus. The data obtained from this study showed differentiation between wisent (Bison bonasus) from bison (Bison bison) and cattle. It can be used in assessing the population genetic parameters of wisent, identifying and eliminating hybrid individuals. It also can be used in developing strategies and measures for the preservation and improvement of the wisent genetic resources.

Assessing the Potential of Extra-Early Maturing Landraces for Improving Tolerance to Drought, Heat, and Both Combined Stresses in Maize

Maize landrace accessions constitute an invaluable gene pool of unexplored alleles that can be harnessed to mitigate the challenges of the narrowing genetic base, declined genetic gains, and reduced resilience to abiotic stress in modern varieties developed from repeated recycling of few superior breeding lines. The objective of this study was to identify extra-early maize landraces that express tolerance to drought and/or heat stress and maintain high grain yield (GY) with other desirable agronomic/morpho-physiological traits. Field experiments were carried out over two years on 66 extra-early maturing maize landraces and six drought and/or heat-tolerant populations under drought stress (DS), heat stress (HS), combined both stresses (DSHS), and non-stress (NS) conditions as a control. Wide variations were observed across the accessions for measured traits under each stress, demonstrating the existence of substantial natural variation for tolerance to the abiotic stresses in the maize accessions. Performance under DS was predictive of yield potential under DSHS, but tolerance to HS was independent of tolerance to DS and DSHS. The accessions displayed greater tolerance to HS (23% yield loss) relative to DS (49% yield loss) and DSHS (yield loss = 58%). Accessions TZm-1162, TZm-1167, TZm-1472, and TZm-1508 showed particularly good adaptation to the three stresses. These landrace accessions should be further explored to identify the genes underlying their high tolerance and they could be exploited in maize breeding as a resource for broadening the genetic base and increasing the abiotic stress resilience of elite maize varieties.

Updates on Ecology and Life Cycle of Sulcascaris sulcata (Nematoda: Anisakidae) in Mediterranean Grounds: Molecular Identification of Larvae Infecting Edible Scallops.

Sulcascaris sulcata is a nematode parasite of sea turtles, widespread in neritic foraging grounds with variable prevalence, reaching 30% in loggerhead turtles Caretta caretta feeding in northern Adriatic Sea. Ulcerative gastritis associated to high intensity of infection is reported in this host species. The life cycle of S. sulcata has been elucidated in Australian and American waters, demonstrating the ability of the species of infecting a wide range of intermediate hosts, represented by bivalve and gastropod molluscs. During regular sanitary inspections, nematode larvae were found within the adductor muscle of Pecten jacobeus and Aequipecten opercularis collected from the Northern Adriatic Sea. Morphological and molecular analyses were performed for the identification of larvae, and molecular data were obtained from adult S. sulcata as well. Analysis of the sequences of ITS fragment, and mitochondrial genes cox1 and cox2, revealed high genetic similarity among all the samples, and no geographical clustering was observed between adult parasites collected in Adriatic and Tyrrhenian Seas. A common allele pool was detected also between the two developmental stages, included larvae from Pecten and Aequipecten. The comparison with other members of the family Anisakidae demonstrated that S. sulcata formed a clear monophyletic cluster. This study reports the first identification of intermediate hosts for S. sulcata within the Mediterranean Sea. Infection in edible scallops justifies the exclusion of the product from the market and zoonotic potential of larvae of this anisakid nematode are yet to be completely excluded. Fidelity of sea turtles to selected foraging grounds, such as the Northern Adriatic shelf, warrants the life cycle of S. sulcata to perpetrate in the area; at the same time, long distance migrations of individuals justify the dispersal of infecting elements over the Mediterranean basin, regardless of turtles' origin.

Genome-wide association study of agronomic and quality traits in a world collection of the wild wheat relative Triticum urartu.

Triticum urartu (2n=2x=14, subgenome Au Au ), a wild diploid wheat progenitor, features broad allelic diversity for a number of traits of agronomic relevance. A thorough characterization of the diversity of T.urartu natural accessions may provide wheat breeders with new alleles potentially contributing to wheat improvement. In this study, we performed an extensive genotypic and phenotypic characterization of a world collection of 299 T.urartu ex situ accessions, developing 441327 single nucleotide polymorphisms and recording trait values for agronomic and quality traits. The collection was highly diverse, with broad variation in phenology and plant architecture traits. Seed features were also varied, and analyses of flour quality reported 18 distinct patterns of glutenins, and carotenoid concentrations and sedimentation volumes in some cases surpassing those of cultivated materials. The genome-wide molecular markers developed on the collection were used to conduct a genome-wide association study reporting 25 highly significant quantitative trait nucleotides for the traits under examination, only partially overlapping loci already reported in wheat. Our data show that T.urartu may be considered a valuable allele pool to support the improvement of wheat agronomy and quality.