Gene Pool Of Population Research Articles

Continuous Storage Root Formation and Bulking in Sweetpotato

This study investigated the phenotypic variation of continuous storage root formation and bulking (CSRFAB) growth patterns underlying the development of sweetpotato genotypes for identification of potential varieties adapted to piecemeal harvesting for small scale farmers. The research was conducted between September 2016 and August 2017 in Uganda. Genotypes from two distinct sweetpotato genepool populations (Population Uganda A and Population Uganda B) comprising 130 genotypes, previously separated using 31 simple sequence repeat (SSR) markers were used. Measurements (4 harvest times with 4 plants each) were repeated on genotypes in a randomized complete block design with 2 replications in 2 locations for 2 seasons. We developed a scoring scale of 1 to 9 and used it to compare growth changes between consecutive harvests. Data analysis was done using residual or restricted maximum likelihood (REML) in GenStat 18th Edition. There were strong linear and quadratic trends over time (P<0.001) indicating a non-linear growth pattern within and between locations, seasons, and genotypes for most traits. Some genotypes displayed early initiation and a determinate linear increase of bulking, while others showed late initiation following a quadratic growth pattern. Broad sense heritability of CSRFAB would be low due to large GxE interactions, however, it was relatively high (50.5%) compared to other yield related traits indicating high genetic influence and accuracy of the developed method to quantify yield overtime. A high level of reproducibility (89%) was observed comparing 2017A and 2017B seasons (A and B are first and second season, respectively) at the National Crops Resources Research Institute (NaCRRI), Namulonge, Uganda. Choosing CSRFAB genotypes can more than double the sweetpotato production (average maximum yield of 13.1 t/ha for discontinuous storage root formation and bulking (DSRFAB) versus 28.6 t/ha for CSRFAB demonstrating the importance of this underresearched component of storage root yield.

Genetic characterization of Akhal-Teke horse subpopulations using 17 microsatellite loci

Akhal-Teke is the ancient cultural horse breed of oriental origin. The study of genetic features different subpopulations of Akhal-Teke breed was carried out on 17 loci of DNA microsatellites (VHL20, HTG4, AHT4, HMS7, HTG6, AHT5, HMS6, ASB23, ASB2, HTG10, HTG7, HMS3, HMS2, ASB17, LEX3, HMS1 and CA425) to assess their genetic differentiation. The results of DNA typing of 5457 Akhal-Teke horses on 17 microsatellite loci show that gene pool of world population is represented by 121 alleles, among which 98 are found in all countries. Comparative analysis of genotypes of horses representing different subpopulations indicates that they differ in the number of alleles (100-117), allele frequencies, the level of polymorphism Ae (3.40-3.91) and the degree of observed heterozygosity Ho (0.661-0.724). The genetic distances between the subpopulations varied in range from 0.007 (Russia – CIS) to 0.051 (Czechia – Turkmenistan). Correspondence to HWE was maintained in all countries, which confirms the negative value Fis. Genetic options of the Akhal-Teke by index Fst varied in a range 0.001 -0.078 at the mean value Fst=0.022. Cluster analysis demonstrated more close relationship between Russian, CIS and European subpopulations.

Study of genetic effects of radiation contaminated territories on biota

Industrial factors, the forceful action of full elementary evolutionary processes can lead to qualitative transformations of the gene pool of populations. Observations in the field and experiments made itpossible to establish a previously unknown fact that complexes of soil animals with chronic irradiationwith doses of the order of 0,5-20 mSv/day experience clearly recorded oppression. Especially sensitiveare earthworms Eisenia fetida. Among the cells with chromosome structure disorders, chromosomaltype aberrations (67,04%) over chromatid (32,95%) prevailed, which indicates a predominant radiationexposure. The study of chromosomal aberrations in natural populations and the human body acquires aspecial practical and theoretical significance in connection with the influence of factors of the changinghabitat. But, an important element of the set of works to determine the degree of impact of the activitiesof radiation contaminated territory on the environment and public health is the conduct of ecologicalgenetic and medical-biological research in the region. The purpose of this publication – on the basic ofscientific research results to analyze the current state on the habitat of radiation-contaminated territoriesand the evaluation their genetically consequence of animal and human body.Key words: radiation, cytogenetic, ecology, chromosome, population.

Genetic Demography of the Population of St. Petersburg: Migration Processes

The principal genetic demographic parameters that describe migration processes affecting the structure of the St. Petersburg population gene pool were determined on the basis of the demographic statistics obtained from the Petrostat Agency, All-Russian population censuses, and a sample survey of St. Petersburg residents. The migration coefficient was 0.36 according to the survey data, 0.42 according to the 2002 census, 0.44 according to the 2010 census, and 0.69 according to the 1897 census. The estimated average migration distance was 1746 km from the survey data, 1526 km according to the 2002 census, and 1652 km according to the 2010 census. The sources of the St. Petersburg population gene pool in different periods are discussed: in the 18th and 19th centuries, the main source was the population of the Upper Volga and Northwestern provinces of the Russian Empire, as well as foreign immigrants, whereas currently three quarters of the population gene pool originates from the Northwestern Federal District, 10% comes from natives of foreign countries, and only 6–9% is due to the population of the Central Federal District of the Russian Federation. An analysis of the Rosstat migration statistics showed that the composition of migrants by countries of exit varied over time. For instance, the share of migrants who arrived in St. Petersburg from Russia in the last five years ranged from 74 to 87%. In 2013–2014, most international migrants came from Uzbekistan (10% of all arrivals) and Tajikistan (3–4%), while in 2017, the countries with the highest number of migrants ranked as follows: Kyrgyzstan (almost 4%), Ukraine (about 2%), Belarus (1.5%), Kazakhstan (1.25%), and Armenia (1%). Migration processes determine the dynamics of the ethnic composition of the population. Gender differences in migration flows are manifested in different age structure and in unequal sex ratio within particular ethnic groups (e.g., predominance of men in the “young” ethnic diasporas: Armenians, Azerbaijani, and Uzbeks). The described features of migration processes in St. Petersburg should be taken into account when forming genetic marker databases for the purposes of DNA-based identification. The areas of migration attraction of St. Petersburg and Moscow overlap only partially, which predetermines the need to create separate databases for each megacity.

Assessment of line differentiation in the Thoroughbred horse breed using DNA microsatellite loci

The Thoroughbred (TB) horse is the best racehorse breed used in the racing industry. This breed has had a closed studbook for about 300 years. In Russia TB horses have been bred since the second half of the XVIII century. The modern Russian Stud Book register of TB horses is partially presented by stallions and broodmares imported from different countries. The genealogical structure of the breed is represented by 17 lines, among which the Northern Dancer line dominates (30.9 %). The study of features of different lines of TB was carried out on 17 loci of DNA microsatellites (VHL20, HTG4, AHT4, HMS7, HTG6, AHT5, HMS6, ASB23, ASB2, HTG10, HTG7, HMS3, HMS2, ASB17, LEX3, HMS1 and CA425) to assess genetic differentiation of the genealogical structure. The results of the DNA typing of 8091 Thoroughbred horses across microsatellite loci show that the gene pool of the domestic population is represented by 100 alleles typical of the breed. A comparative analysis of the genotypes of horses representing different lines indicates that they differ in the number of alleles (85–99), allele frequencies, the level of polymorphism Ae (2.93–3.48) and the degree of the observed heterozygosity Ho (0.653–0.739). The genetic distances between the lines varied in a wide range from 0.014 (Nasrullah – Northern Dancer) to 0.125 (Massine – Teddy). The correspondence to HWE was maintained in most lines, which is confirmed by the negative values of Fis. Cluster analysis demonstrated the correspondence of the obtained dendrogram of Nei’s genetic distances to its genealogical scheme of lines. Genetic differentiation of lines by index Fst varied in a range 0.005–0.073 at the mean value Fst = 0.024. The data indicate genetic differentiation of lines of TB at the STR markers and confirm the effectiveness of the system of linear breeding for the maintenance of interbreed biodiversity.

The genetic assessment of the natural regeneration capacities of black poplar populations in the modern river valley landscapes

Black poplar (Populus nigra L.) is an economically and ecologically important tree species which in the past was widely distributed along riversides in vast areas of Europe. Currently, it deserves conservation with a view of serious threats resulting from the species habitat reduction and progressive introgressive hybridization. Here we examined the regeneration capacities of black poplar populations from the Vistula River in Poland in a region which has been influenced by man-made disturbance regimes. Using both nuclear (nDNA) and chloroplast (cpDNA) genetic markers and spatial location data we: (1) evaluated the susceptibility of the studied populations to introgression, (2) determined genetic diversity of the analyzed offspring and compared it with their maternal stands, and (3) assessed the level of gene flow among populations and generations. Nine hybrid individuals were identified in the examined groups of one-year poplar seedlings. Both molecular variance and clustering analyses showed that the gene pool of black poplar populations was homogenous (FST = 0.004, p = 0.623). Heterozygosity and allelic richness were comparable between adult and their progeny populations, and there were also no strong disturbances in a random distribution of genotypes in the study area. Low spatial genetic structure was observed in two seedling groups and among all black poplar individuals from the Wysoczyn population. The results are discussed in the context of natural regeneration capacities of the remaining black poplar populations and protection of the species genetic resources along the landscapes of the river valleys.

River Valleys Shaped the Maternal Genetic Landscape of Han Chinese.

A general south-north genetic divergence has been observed among Han Chinese in previous studies. However, these studies, especially those on mitochondrial DNA (mtDNA), are based either on partial mtDNA sequences or on limited samples. Given that Han Chinese comprise the world's largest population and reside around the whole China, whether the north-south divergence can be observed after all regional populations are considered remains unknown. Moreover, factors involved in shaping the genetic landscape of Han Chinese need further investigation. In this study, we dissected the matrilineal landscape of Han Chinese by studying 4,004 mtDNA haplogroup-defining variants in 21,668 Han samples from virtually all provinces in China. Our results confirmed the genetic divergence between southern and northern Han populations. However, we found a significant genetic divergence among populations from the three main river systems, that is, the Yangtze, the Yellow, and the Zhujiang (Pearl) rivers, which largely attributed to the prevalent distribution of haplogroups D4, B4, and M7 in these river valleys. Further analyses based on 4,986 mitogenomes, including 218 newly generated sequences, indicated that this divergence was already established during the early Holocene and may have resulted from population expansion facilitated by ancient agricultures along these rivers. These results imply that the maternal gene pools of the contemporary Han populations have retained the genetic imprint of early Neolithic farmers from different river basins, or that river valleys represented relative migration barriers that facilitated genetic differentiation, thus highlighting the importance of the three ancient agricultures in shaping the genetic landscape of the Han Chinese.

Structure and Forming of Mitochondrial Gene Pool of Russian Population of Eastern Europe

Phylogeographic analysis of the variability of whole mitochondrial genomes in the Russian populations of Eastern Europe (n = 557) showed that, in the Russian mitochondrial gene pool, there were subgroups of mtDNA characteristic only of Russians and other Eastern Slavs (11.7%), as well as of Slavs as a whole (12.2%), Slavs and Germans (6.6%), and Slavs and Baltic Finns (5.7%). The results of molecular dating suggest that the mitochondrial subgroups characteristic of Russians and Slavs in general began to arise 2700–3500 years ago. The results of the study of the dynamics of the effective population size based on the Bayesian analysis of data on the variability of mtDNA haplotypes specific to Russians and Slavs showed that a rapid increase in population sizes occurred immediately after its decline 4000–5000 years ago. The data obtained are discussed in comparison with the results of the analysis of Y-chromosome polymorphism in European populations.

Genetic diversity and matrilineal genetic origin of fat-rumped sheep in Ethiopia

Ethiopia is home to a diverse gene pool of indigenous sheep populations. Therefore, a better understanding of genetic variation holds the key to future utilization through conservation. Three of these breeds, Afar, Blackhead Somali, and Hararghe Highland, are found in eastern Ethiopia where they contribute significantly to the livelihood of most pastoralist, agro-pastoralist, and smallholder farmers. These indigenous sheep are recognized on the basis of morphotype and their genetic distinction remains unknown. Here, to assess genetic variation, and matrilineal genetic origin and relationship of fat-rumed sheep found in eastern Ethiopia, 300 individuals from the three breeds were genotyped for 22 microsatellite markers and sequenced for the mitochondrial DNA displacement loop (mtDNA d-loop) region. The overall HO and HE were 0.57 and 0.75, respectively. Differentiation statistics revealed that a high proportion (97%) of the total genetic variation was explained by differences between individuals within populations. Genotype assignment independent of the population of origin showed K = 2 to be the optimum number of genetic backgrounds present in the dataset. This result was further confirmed by mtDNA D-loop sequences comparison in which the matrilineal genetic origin of eastern Ethiopia sheep is from two haplotype groups (types A and B) among the five haplotypes globally observed. Taken together, our findings suggest that the sheep populations from three breeds originated from two ancestral genetic backgrounds that may have diverged prior to their introduction to Ethiopia. However, to obtain a complete picture of the evolutionary dynamics of Ethiopian indigenous sheep, more samples and populations from within and outside of the country will need to be analyzed.

Analysis of the genetic structure of a population of Lebedyn cattle by microsatellite markers

Microsatellites – a separate class of molecular genetic markers, are widely used for the study of genetic variability, in particular in populations of animals bred by artificial selection under the influence of microevolutionary processes. The object of study is the gene pool of a population of animals of the Lebedyn cattle breed, which is under threat of extinction. The sample comprised 30 individuals from the farm "Komyshans'ke" in Sumy region. The analysis of population genetic structure was performed using 10 microsatellite loci recommended by FAO-ISAG: ETH225, BM2113, ETH3, BM1818, BM1824, ILSTS006, INRA023, TAGLA053, TAGLA12, ETH10. Amplification products were separated in polyacrylamide gels of different concentrations (5–8%), both native and denaturing. All studied loci were polymorphic. The number of detected alleles per locus ranged from 4 to 8 (on average 5 alleles per locus), the size of which ranged from 115 bp (ETH3) to 307 bp (ILSTS006). The majority of the investigated loci (except ETH3) belonged to valuable informative markers (PIC > 0.5). The most polymorphic TGLA053 (8 alleles), BM2113 (6) and ETH3 (6) loci have been identified. In general, the minimum number of alleles (4) was fixed in 50% loci. The main population genetic parameters for the studied loci have been calculated. The highest values of heterozygosity (He), and effective number of alleles (ne) was characterized for loci BM2113, ILSTS006, TGLA053 and ETH225. With the exception of ETH3 and VM1818 loci, the experimental group of animals is in a state of genetic equilibrium. The average value of the Wright fixation index indicates a tendency to increase in the number of homozygous individuals (inbreeding). Comparative analysis of genetic structure of breeds that have a common origin (Lebedyn (PJSC "Mykhaylivka"), Ukrainian grey (DPDG "Polyvanivka"), Red steppe (DPPR "Stepne"), etc.) has been carried out. The obtained results give grounds to assert that in the experimental population of the Lebedyn breed there are processes that lead to a decrease in genetic diversity. In order to overcome the negative effects of artificial reproduction in the gene pool of small populations of cattle, which include Lebedyn cattle, it is appropriate to use microsatellite markers in the selection and breeding work.

Continuous Storage Root Formation and Bulking in Sweetpotato

This study investigated the phenotypic variation of continuous storage root formation and bulking (CSRFAB) growth patterns underlying the development of sweetpotato genotypes for identification of potential varieties adapted to piecemeal harvesting for small scale farmers. The research was conducted between September 2016 and August 2017 in Uganda. Genotypes from two distinct sweetpotato genepool populations (Population Uganda A and Population Uganda B) comprising 130 genotypes, previously separated using 31 simple sequence repeat (SSR) markers were used. Measurements (4 harvest times with 4 plants each) were repeated on genotypes in a randomized complete block design with 2 replications in 2 locations for 2 seasons. We developed a scoring scale of 1 to 9 and used it to compare growth changes between consecutive harvests. Data analysis was done using residual or restricted maximum likelihood (REML). Data showed a non-linear growth pattern within and between locations, seasons, and genotypes for most traits. Some genotypes displayed early initiation and increase of bulking, while others showed late initiation. Broad sense heritability of CSRFAB was low due to large GxE interactions but higher in other traits probably due to high genetic influence and the effectiveness of the methodology. A high level of reproducibility (89%) was observed comparing 2016B and 2017A seasons (A and B are first and second season, respectively) at the National Crops Resources Research Institute (NaCRRI), Namulonge, Uganda. Choosing CSRFAB genotypes can more than double the sweetpotato production (average maximum yield of 13.1 t/ha for discontinuous storage root formation and bulking (DSRFAB) versus 28.6 t/ha for CSRFAB, demonstrating the importance of this underresearched component of storage root yield.

Continuous Storage Root Formation and Bulking in Sweetpotato.

This study investigated the phenotypic variation of continuous storage root formation and bulking (CSRFAB) growth patterns underlying the development of sweetpotato genotypes for identification of potential varieties adapted to piecemeal harvesting for small scale farmers. The research was conducted between September 2016 and August 2017 in Uganda. Genotypes from two distinct sweetpotato genepool populations (Population Uganda A and Population Uganda B) comprising 130 genotypes, previously separated using 18 simple sequence repeat (SSR) markers were used. Repeated measurements (4 harvest times with 4 plants each) on genotypes in a randomized complete block design with 2 replications in 2 locations for 2 seasons were used. We developed a scoring scale of 1 to 9 and used it to compare growth changes between consecutive harvests. Data analysis was done using residual or restricted maximum likelihood (REML) in GenStat 18th Edition. There were strong linear and quadratic trends over time (P<0.001) indicating a non-linear growth pattern within and between locations, seasons, and genotypes for most traits. Some genotypes displayed early initiation and a determinate linear increase of bulking, while others showed late initiation following a quadratic growth pattern. Broad sense heritability of CSRFAB would be low due to large GxE interactions, however, it was relatively high (50.5%) compared to other yield related traits indicating high genetic influence and accuracy of the developed method to quantify yield overtime. High level of reproducibility (89%) was observed comparing 2017A and 2017B seasons at Namulonge (NaCRRI). Choosing CSRFAB genotype can more than double the sweetpotato production (average maximum yield of 13.1 t/ha for discontinuous storage root formation and bulking (DSRFAB) versus 28.6 t/ha for CSRFAB demonstrating the importance of this under researched component of storage root yield.

Morphological and pomological characterizations of cornelian cherry (Cornus mas L.) to select the superior accessions

The fruits of cornelian cherry (Cornus mas L.) are rich in tannins, ascorbic acid, and anthocyanin and are mainly used for food and medicine. In the present study, phenotypic variation of 122 seedlings originated accessions of cornelian cherry was investigated to select the superior trees. Analysis of variance showed significant differences in the majority of traits measured among the studied accessions. Fruit length varied from 14.84 to 22.57 mm and fruit width ranged from 10.31 to 16.71 mm. Fruit weight varied between 1.23 and 3.79 g and also fruit stone weight ranged from 0.19 to 0.59 g. In addition, fruit taste in the majority of accessions was sour, while red fruit color was predominant. Fruit weight was positively correlated with fruit length and fruit width. Fruit flesh percentage was found to be associated negatively with fruit stone weight and positively with fruit weight and thus they should be considered together in breeding programs. Cluster analysis grouped the accessions into two major clusters and revealed considerable phenotypic diversity in the germplasm. In conclusion, 21 accessions showed high values in terms of fruit quality traits and may be especially useful for cultivation and/or for developing cultivars with greater horticultural potential. In addition, the studied accessions may be recognized as representative gene pool of natural populations of cornelian cherry.

СОСТОЯНИЕ ЗАПАСОВ ПРОМЫСЛОВЫХ ГИДРОБИОНТОВ КИЕВСКОГО И КАНЕВСКОГО ВОДОХРАНИЛИЩ

The article analyzes the data of monitoring control catches in the Kiev and Kanev reservoirs, which are a part of the Dnieper cascade of hydroelectric stations. The analysis results allow to assess the current ecological and biological status of the populations of the main fish species in the conditions of anthropogenic impact. The analysis is based on the data of spring control catches carried out by the researchers of Institute of Hydrobiology of National Academy of Science of Ukraine in 2015. It has been stated that generally stocks of valuable commercial fish in the Kiev and Kanev reservoirs can be characterized as stable. Bream and silver bream populations of the Kanev reservoir are in good conditions in terms of reasonable exploitation of commercial core. Conditions for fattening and forming commercial core are estimated as favorable. There has been stated an increase of crucian population due to the low catches and few number of predatory fishes. Dominating commercial species in 2015 in the Kanev reservoir there were roach, bream, crucian, pike perch. There has been registered growing population of cat fish, dynamic recruit-stock of asp, and commercially abundant population of perch. To restore the commercial size of ide population it has been suggested to artificially stock the water reservoir with fish in terms of the state demand. The results of the conducted research help to predict the dynamics of fishing, to scientifically justify the ways of preserving the gene pool of natural fish populations, to take timely measures to limit the catch and further rationalization of the fishery use of the Kiev and Kanev reservoirs in order to develop the concept of stable operation of large fishery reservoirs

Effect of intermittent drought on phenotypic traits of F5 RIL Andean intra-gene cross population (BRB 191 X SEQ 1027) of common bean

Drought is a major constraint to common bean ( Phaseolus vulgaris L.) production in East Africa, where irrigation for the crop is very uncommon. The objective of this study was to identify drought tolerant lines and phenotypic traits underlying drought tolerance among 128 F5 recombinant inbred lines (RILs), derived from intra gene pool population, between drought tolerant BRB 191 (source of bc-3) and SEQ 1027. The population was evaluated with eight experimental checks that included BAT 477, CAL 96, DAB 441, DAB 494, and Diacol Calima, NABE 4, SCR 9 and SEQ 1003. A total of 20 phenological, morphological and physiological shoot traits were evaluated, under drought and non-stress conditions, in the field for 2 years (2014 and 2015) at Kawanda in Uganda. New sources of drought tolerance, and previously identified sources of drought tolerance in common bean (BAT 477, DAB 441 and DAB 494), were confirmed based on their superior geometric means and low drought susceptibility. Drought stress in the field significantly affected all measured traits, except harvest index and stem dry weight reduction (P<0.001). Drought significantly reduced yield, yield components and pod harvest index (P<0.01). However, chlorophyll content, canopy temperature, stem dry mass reduction, and 100 seed weight remained stable under season by genotype by water regime treatment interactions (S x G x T). The stability of these traits highlighted their usefulness in selecting for drought tolerance across different environments. Furthermore, pod partitioning index (PPI), harvest index (HI), chlorophyll content and stem dry weight reduction also remained stable under G x T effects. Significant correlations (P<0.001) were maintained between HI and PPI with seed yield under drought stress in field conditions, indicating that photosynthate remobilisation increases yield under drought stress conditions. Key words: Phaseolus vulgaris , photosynthate remobilisation

Mitochondrial Polymorphism of Native and Invasive Populations of Harmonia axyridis (Coleoptera, Coccinellidae)

Ladybird Harmonia axyridis is a widespread polyphage and forms stable populations in East Asia and spreading invasive populations in Europe and other regions with temperate and subtropical climate. A characteristic of haplotype diversity of native and invasive populations of H. axyridis at the atp6 gene is given. The characteristic differences in the composition and quantitative ratio of mitochondrial haplotypes between the western and eastern groups of populations of the native range are revealed. The genetic structure of invasive populations is uniform across the whole range in Europe, from the Atlantic coast to the Black Sea coast of the Caucasus, which is indicative of the spread of H. axyridis invasive populations in Europe from one center. In Europe, the mitochondrial gene pool of invasive populations is formed by two major haplotypes. This mitochondrial haplotype composition remains unchanged in the process of the invasion expansion. The possible role of mixed origin of invasive populations of H. axyridis in the formation of the invasive ability is discussed.

Mitochondrial DNA diversity of the Roma from northeastern Bosnia, Bosnia and Herzegovina

This study is the first report on the mtDNA diversity in the Roma population from Bosnia. The main aim of this study was to analyse the mtDNA diversity in the studied population, evaluate the genetic relations with other European Roma populations, and analyse the influences of the Roma gene flow on the mitochondrial profile of the Roma from northeastern Bosnia. MtDNA variability in the analysed population has been studied by means of hypervariable segment I and II (HVSI/II) of the control region sequencing and analysis of restriction fragment-length polymorphisms of the coding region. Our results show that genetic structure of the Roma from northeastern Bosnia has a combination of lineages of three main layers: specific founder of Indian origin (M5a1 and M35b) and founder non-M lineages of Indian/European origin (H7a, X2b and X2d) and lineages of European/Middle East origin (H, H1, H11a, V, T2b, K1b and W). The distribution of the haplogroups in the gene pool of the comparative European Roma populations indicates the separate origin of the Bosnian Roma and the Bulgarian Vlax and Croatian Vlax Roma. The data suggest that mitochondrial gene pool of the Roma population from northeastern Bosnia might be a consequence of early parting and the later different migration routes that are part of their demographic history. Our data confirm the high genetic heterogeneity of the Roma populations that can be shaped by effects of genetic drift, isolation and low effective population size, and this correlates with the migratory history of the Roma.

Genome variations between rhizosphere and bulk soil ecotypes of a Pseudomonas koreensis population.

Bulk soil and rhizosphere are soil compartments selecting different microbial communities. However, it is unknown whether this selection also can change the genome content of specific bacterial taxa, splitting a population in distinct ecotypes. To answer this question we compared the genome sequences of 53 isolates obtained from sugarcane rhizosphere (28) and bulk soil (25). These isolates were previously classified in the Pseudomonas koreensis subgroup of the P. fluorescens complex. Phylogenomics showed a trend of separation between bulk soil and rhizosphere isolates. Discriminant analysis of principal components (DAPC) identified differences in the accessory genome of rhizosphere and bulk soil sub-populations. We found significant changes in gene frequencies distinguishing rhizosphere from bulk soil ecotypes, for example, enrichment of phosphatases and xylose utilization (xut) genes, respectively. Phenotypic assays and deletion of xutA gene indicated that accumulation of xut genes in the bulk soil sub-population provided a higher growth capacity in a d-xylose medium, supporting the corresponding genomic differences. Despite the clear differences distinguishing the two ecotypes, all 53 isolates were classified in a single 16S rRNA gene OTU. Collectively, our results revealed that the gene pool and ecological behavior of a bacterial population can be different for ecotypes living in neighbouring soil habitats.

Comparative Assessment of the Gene Pool and the Viability of Forest Plantations from Moscow and Natural Populations from the Moscow Region by Example of Norway Spruce (Picea abies (L.) Karst.)

The genetic diversity of four population of Norway spruce (Picea abies (L.) Karst.) in Moscow parks have been studied. For the first time, a comparison of the gene pool of planted stands in urban areas with the gene pool of natural populations and planted stands of the Moscow region investigated earlier revealed a significant reduction in the genetic diversity of planted stands of Moscow parks in comparison with conditionally native populations from the Moscow region. In three of the four urban planted stands, a decrease was revealed in the proportion of polymorphic loci (down to 0.41 and 0.50) compared to conditionally native forests (0.64). All plant stands do not differ from conditionally native in terms of average heterozygosity and average number of alleles per locus. However, the test for allelic frequency heterogeneity demonstrated a significant difference of all planted stands (from Moscow and the Moscow region) from conditionally native populations both by 3–11 loci and by all (17) polymorphic loci. The quality of the gene pool of three of the four Moscow planted stands was evaluated as unsatisfactory and one of them as critical. A reduction in viability of urban planted stands with a reduced gene pool diversity was revealed: two of the three plantations died. In our opinion, this is a consequence of the sharp deviations of the observed diversity of the gene pool of the studied plantations from the natural norm, i.e., an optimal state of the gene pool historical in this natural area. Thus, economic necessity of genetic control over the state of saplings in reforestation is obvious.

Microspatial Structure of Population Gene Pool in the Land Snail Helicopsis striata (Pulmonata, Hygromiidae) in the Conditions of the Southern Mid-Russian Upland

Microspatial differentiation of the population gene pools of the terrestrial mollusk Helicopsis striata (Muller, 1774) is revealed for various conditions of the Southern Mid-Russian Upland, which is caused by the fragmentation of habitats and differences in the intensity of the gene flow between demes. The spatial differentiation of H. striata, due to the special features of its biology, is the highest among other terrestrial mollusks of the studied region. Populations with a low variability and weak gene pool differentiation are demonstrated to be the most vulnerable. The methodological importance of the intrapopulation structure of the species is specifically noted for the works on estimating the state of the population’s gene pools, since the single datasets of individual demes cannot demonstrate the true nature of the genetic structure of the populations.