Low Genetic Connectivity of Strongly Inbred Ruppia brevipedunculata in Aquaculture Dominated Lagoons (Viet Nam)

Lagoonal environments exhibit high levels of instability depending on hydrological, climatic and ecological factors, thereby influencing the distribution and structure of submerged plant communities. Conditions typically fluctuate widely due to the interaction of freshwater from rivers with saltwater from the sea, as well as from aquaculture activities that together influence submerged hydrophyte community spatial and temporal variability depending on plant survival strategies. Ruppia species feature either underwater pollination mediated by an air bubble or by the release of pollen floating at the water surface, the former promoting self-pollination. Tropical Asian Ruppia brevipedunculata Yu and den Hartog was assumed to pollinate below the water surface and identified as a separate lineage among selfed Ruppia taxa. We used nine nuclear microsatellites to estimate inbreeding levels and connectivity of R. brevipedunculata within a large SE Asian lagoon complex. Ruppia brevipedunculata meadows were strongly inbred as could be derived from the many monomorphic or totally fixed loci for unique alleles in different parts of the lagoon, which appears consistent with selfing behavior. Those from aquaculture ponds were highly inbred (FIS = 0.620), though less than open lagoon sites that showed nearly total inbreeding (FIS = 0.942). Ruppia brevipedunculata from two major lagoon parts were highly differentiated with spatially structured gene pools and a strong barrier between parts of the lagoon over a 30 km distance. Migration-n analysis indicated unidirectional though limited gene flow and following potential hydrological connectivity. Overall, private alleles under homozygote conditions explained a stronger genetic differentiation of populations situated inside aquaculture ponds than of open lagoon populations. Kinship values were only relevant up to 5 km distance in the open lagoon. Within a confined area of aquaculture ponds featuring dense vegetation in stagnant water, there would be opportunity for mixed pollination, thereby explaining the higher diversity of unique multilocus genotypes of aquaculture pond habitats. Low connectivity prevents gene pools to homogenize however promoted sites with private alleles across the lagoon. Complex hydrodynamic systems and human-made habitats enclosed by physical structures impose barriers for propagule dispersal though may create refugia and contribute to conserving regional genetic diversity.

Creation of breeding herds in the Belarusian factory type of Yorkshire pigs on the basis of new factory lines using microsatellite markers

Based on the conducted studies using DNA testing and microsatellite markers, the genealogical structure and microsatellite profile of breeding herds of White-Russian factory-type Yorkshire pigs created in JSC «SGC «Zapadny» and SE «Zhodinoagroplemelita» were developed, which are based on the new lines Drug6805 and Dobry 2313. The average number of private alleles in loci in boars of different lines was 0,111–0,593. The created breeding herds and new lines will serve as the basis for the breeding of the factory type of pigs in the Yorkshire breed.

KERAGAMAN GENETIK AQUILARIA MALACCENSIS DARI BANGKA BARAT DAN IMPLIKASINYA UNTUK PENGELOLAAN TEGAKAN BENIH

Aquilaria malaccensis (agarwood) is a native species to Indonesia, it produces fragrance. Aim in this study was to assess genetic diversity and structure of A. malaccensis in order to manage seed stand to produce high quality and quantity seeds/seedlings. Leaf samples for DNA template were collected from populations at western Bangka i.e. Air Gantang, Pelangas, and Simpang Gong. Amplifications of 14 RAPD markers were confirmed; 42 DNA samples of A. malaccensis were analysed using RAPD markers. Parameters of genetic diversity within population i.e. private alleles (PA) and expected heterozygosity (H) were calculated using GeneAlex software. Genetic structure among populations were determined as genetic distance (Da), Analysis Molecular of Variance (AMOVA), a neighbor-joining tree, were calculated using GeneAlex and PopTrew software. Eleven out of 14 RAPD markers were produced 104 stable and polymorphic alleles; PE were found at Air Gantang and Pelangas, 1 and 2 alleles, respectively. The H ranged between 0.133 (Simpang Gong) and 0.328 (Pelangas). The Da was moderate (0.099). AMOVA showed significant genetic diversity among populations (14%). A neighbor-joining tree showed the populations divided into two clusters with high boostrap value, and concordance with their geographical positions. Restricted gene flow might cause a high genetic relationship among populations. Low HEE in Simpang Gong caused this population was priored to being conserved; Air Gantang and Pelangas should be designed as different conservation units due to the population contained different private alleles.

PSXII-27 Microsatellite analysis of the historical and modern populations of the Russian local cattle breeds

During the last centuries, a variety of cattle breeds adapted to the local climatic conditions have been developed in different countries. However, in the 20th century many of them were replaced by high-producing industrial breeds, which can lead to the losses of biodiversity. Our aim was to estimate the genetic diversity of Russian native cattle breeds based on the analysis of historical (museum) and modern samples. Historical samples were derived from the craniological collection of the Museum of Livestock named after E.F. Liskun (Moscow). Forty-six samples including Kholmogor (n = 18), Yaroslavl (n = 19), Saratov (n = 5), Novgorod (n = 2) and Great Russian cattle (n = 2) were subjected to the study. Holland cattle (n = 3) was additionally included in the study due to their possible contribution in forming Russian cattle breeds. The modern samples were presented by Yaroslavl (n = 62) and Kholmogor (n = 177) breeds, and Holstein breed (n = 158) was used as an outgroup. All of the works with historical samples were carried out in the facility of the L.K. Ernst Federal Science Center dedicated for the work with ancient DNA. Nine microsatellite loci (TGLA227, BM2113, ETH10, SPS115, TGLA122, INRA23, TGLA126, ETH225, and BM1824) were successfully amplificated in all samples. We observed the higher variability in historical samples comparing to modern samples: the values of unbiased expected heterozygosity were 0.65–0.85 and 0.70–0.74; the values of rarified allele richness were 2.72–3.11 and 2.63–2.76, respectively. The total number of private alleles was higher in historical populations (16) comparing to modern ones (12). The genetic relationship between historical and modern populations were evaluated. Our results indicate a decrease in genetic diversity in modern populations and a possible loss of valuable allelic combinations. The research results will be useful for development of comprehensive strategies for the conservation of the Russian native genetic resources of cattle. The study was funded by RSF №19-76-20012.

Allelic diversity and patterns of selection at the major histocompatibility complex class I and II loci in a threatened shorebird, the Snowy Plover (Charadrius nivosus)

Background Understanding the structure and variability of adaptive loci such as the major histocompatibility complex (MHC) genes is a primary research goal for evolutionary and conservation genetics. Typically, classical MHC genes show high polymorphism and are under strong balancing selection, as their products trigger the adaptive immune response in vertebrates. Here, we assess the allelic diversity and patterns of selection for MHC class I and class II loci in a threatened shorebird with highly flexible mating and parental care behaviour, the Snowy Plover (Charadrius nivosus) across its broad geographic range. Results We determined the allelic and nucleotide diversity for MHC class I and class II genes using samples of 250 individuals from eight breeding population of Snowy Plovers. We found 40 alleles at MHC class I and six alleles at MHC class II, with individuals carrying two to seven different alleles (mean 3.70) at MHC class I and up to two alleles (mean 1.45) at MHC class II. Diversity was higher in the peptide-binding region, which suggests balancing selection. The MHC class I locus showed stronger signatures of both positive and negative selection than the MHC class II locus. Most alleles were present in more than one population. If present, private alleles generally occurred at very low frequencies in each population, except for the private alleles of MHC class I in one island population (Puerto Rico, lineage tenuirostris). Conclusion Snowy Plovers exhibited an intermediate level of diversity at the MHC, similar to that reported in other Charadriiformes. The differences found in the patterns of selection between the class I and II loci are consistent with the hypothesis that different mechanisms shape the sequence evolution of MHC class I and class II genes. The rarity of private alleles across populations is consistent with high natal and breeding dispersal and the low genetic structure previously observed at neutral genetic markers in this species.

Genetic Diversity and Population Structure in a Regional Collection of Kersting’s Groundnut (Macrotyloma geocarpum (Harms) Maréchal & Baudet)

Kersting’s groundnut is an important source of protein and essential nutrients that contribute to food security in West Africa. However, the crop is still underexploited by the populations and under-researched by the scientific community. This study aimed to investigate the genetic diversity and population structure of 217 Kersting’s groundnut accessions from five origins using 886 DArTseq markers. Gene diversity was low and ranged from 0.049 to 0.064. The number of private alleles greatly varied among populations (42–192) and morphotypes (40–339). Moderate to very high levels of selfing and inbreeding were observed among populations (s=56–85%, FIS=0.389–0.736) and morphotypes (s=57–82%, FIS=0.400–0.691). Moreover, little to very high genetic differentiations were observed among populations (0.006≤FIS≤0.371) and morphotypes (0.029≤FIS≤0.307). Analysis of molecular variance partitioned 38.5% of the genetic variation among and 48.7% within populations (P<0.001). Significant isolations by distance were detected between populations (R2=0.612, P=0.011) and accessions (R2=0.499, P<0.001). Discriminant analysis of principal components and neighbour joining consistently distinguished eight distinct clusters. These data provide a global picture of the existing genetic diversity for Kersting’s groundnut and will guide the choice of breeding strategies to increase production.

GENETIC STRUCTURE OF THE KAZAKH FINE-WOOL SHEEP POPULATION BASED ON MOLECULAR GENETIC MARKERS OF DNA

The modern Kazakh population of sheep of the Kazakh fi newool breed is characterized by the following population-genetic indicators: the average number of alleles (N) – 9.5833, the average heterozygosity (expected, not) – 0.8090, the average heterozygosity (observed, but) – 0.6972, the total expected heterozygosity Ht – 0, 8177 and the individual fi xation index (Fis) – 0.1459. 115 alleles were identifi ed, including 89 typical alleles (with a frequency of more than 0.01), 26 private alleles (with a frequency of less than 0.01), and 68.9 eff ective alleles

The Genetic Structure of the Field Pea Landrace “Roveja di Civita di Cascia”

“Roveja di Civita di Cascia” is a landrace of Pisum sativum grown in marginal land habitats of the Apennines, Central Italy, and is one of the eleven herbaceous crop landraces listed in the Regional Register of local varieties. The objective of the present paper was to assess its genetic structure using 62 morphological traits and five microsatellites. As many as 55 traits showed significant differences with the control entries (P. sativum subsp. sativum var. arvense and var. sativum). We tested P. sativum Simple Sequence Repeats (SSRs) for their transferability to “Roveja”, and found that only 12 out of 35 performed well. Of these, we demonstrated that five were sufficient to assess the genetic structure of this landrace, characterized by several private alleles, differentiating it from Paladio and Bluemoon, which were used as controls. Phenotypic and genotypic data evidenced a genetic structure based on a blend of several pure-bred lines. The sustainability of on-farm landrace conservation is discussed.

Genetic diversity and population structure of indigenous chicken in Rwanda using microsatellite markers

Rwanda has about 4.5 million of indigenous chicken (IC) that are very low in productivity. To initiate any genetic improvement programme, IC needs to be accurately characterized. The key purpose of this study was to ascertain the genetic diversity of IC in Rwanda using microsatellite markers. Blood samples of IC sampled from 5 agro-ecological zones were collected from which DNA was extracted, amplified by PCR and genotyped using 28 microsatellite markers. A total of 325 (313 indigenous and 12 exotic) chicken were genotyped and revealed a total number of 305 alleles varying between 2 and 22 with a mean of 10.89 per locus. 186 distinct alleles and 60 private alleles were also observed. The frequency of private alleles was highest in samples from the Eastern region, whereas those from the North West had the lowest. The influx of genes was lower in the Eastern agro-ecological zone than the North West. The mean observed heterozygosity was 0.6155, whereas the average expected heterozygosity was 0.688. The overall inbreeding coefficient among the population was 0.040. Divergence from the Hardy-Weinberg equilibrium was significant in 90% of loci in all the populations. The analysis of molecular variance revealed that about 92% of the total variation originated from variation within populations. Additionally, the study demonstrated that IC in Rwanda could be clustered into four gene groups. In conclusion, there was considerable genetic diversity in IC in Rwanda, which represents a crucial genetic resource that can be conserved or optimized through genetic improvement.

Higher Effectiveness of New Common Bean (Phaseolus vulgaris L.) Germplasm Acquisition by Collecting Expeditions Associated with Molecular Analyses

A remarkable portion of crop genetic diversity is represented by landraces and obsolete cultivars, that have not yet been integrated into the collections of genetic resources in genebanks. Fortunately, they are still maintained by small farmers in rural areas. Their acquisition is an important goal for collecting expeditions, followed by the evaluation of their genetic background. Molecular markers are powerful tools to evaluate the effectiveness of acquisition of new genetic variants. This approach was used for common bean landraces, that were collected through expeditions in the Slovak and Ukrainian Carpathians. In this study, microsatellite markers, developed from expressed sequence tags, were used for genotyping the collected materials. The sub-population of collected landraces contained higher total and average number of different alleles in comparison to equally large sub-populations of already-maintained cultivars. The same was true for the Shannon’s information index, observed heterozygosity, and expected heterozygosity. Both sub-populations showed the presence of private alleles: Average values of 0.500 and 0.833 private alleles per genotype were detected in landraces, and cultivars, respectively. Obtained results emphasized the importance of collecting expeditions to specific regions where landraces are cultivated, even at the present time. The effectiveness of the acquisition of new genetic variability can be determined by molecular tools, as confirmed by microsatellite markers in this study.