Low Genetic Diversity Research Articles

Population genetic structure of the fibrinogen-related protein 1 (FREP1) in Iranian isolates of Anopheles stephensi as a promising mosquito-based malaria vaccine candidate.

Population genetic structure of the fibrinogen-related protein 1 (FREP1) in Iranian isolates of Anopheles stephensi as a promising mosquito-based malaria vaccine candidate.

Evaluating trace elements as a conservation concern for Eurasian lynx (Lynx lynx) in Switzerland.

Evaluating trace elements as a conservation concern for Eurasian lynx (Lynx lynx) in Switzerland.

Can Inbreeding Increase Viability? A Case Study on An Infectious Outbreak in An Inbred Pigeon Flock

Inbreeding increases homozygosity, resulting in a loss of alleles and lower genetic variation than the parental population. In a small population, this low genetic variation and homozygosity can quickly lead to adverse effects. This study was conducted on a flock of pigeons with 32 adult pigeons. A disease characterized by dyspnea, anorexia, vomiting and sudden death has occurred in birds. Mortality and morbidity were recorded during the outbreak. The inbreeding coefficient was determined in the flock, with pedigree records going back 12 years. Although not significant, the inbreeding coefficient of dead birds are lower than that of symptomatic or healthy birds. It is also seen that there is no statistical significance in terms of inbreeding depression in morbidity or mortality status. The result indicated that inbreeding depression in morbidity and mortality was not observed in this particular disease case.

Population Genomics and Morphology Provide Insights into the Conservation and Diversity of Apis laboriosa.

In recent decades, honeybee populations have declined, dramatically owing to destructive honey harvesting practices and the loss of foraging grounds and nesting sites. Among them, Apis laboriosa Smith, 1871 (Hymenoptera, Apidae), an important pollinator species found in the Himalayan region, holds significant economic and ecological value. However, conservation efforts and intraspecific taxonomic studies regarding it have been rather limited, and thus its full geographic range remains elusive. This study is the first to research A. laboriosa in Sichuan. Through a systematic study integrating morphological feature analysis and genomic data, the following conclusions are drawn. Whole-genome resequencing data analysis reveals that the Sichuan population forms a new monophyletic group (Bootstraps = 100). In the past ten thousand years, the population sizes of A. laboriosa in four different regions of China have been decreasing rapidly. Measures should be taken to protect them across the entire distribution range, especially the populations in Tibet and Sichuan, due to their relatively large genetic differences and low intra-population genetic diversity. Based on the significant difference analysis, the following four wing vein morphological features with extremely significant differences were identified: the width of the right forewing (FB), the cubital index a/b (Ci), the forewing vein angle (E9), and the forewing vein angle (K19). These findings are expected to offer a valuable reference for future A. laboriosa conservation endeavors, particularly in protecting populations with a high level of genetic differentiation.

Development of Single Nucleotide Polymorphism and Phylogenetic Analysis of Rhododendron Species in Zhejiang Province, China, Using ddRAD-Seq Technology.

The genus Rhododendron presents significant challenges for systematic classification due to extensive hybridization and adaptive radiation. Here, we employed double-digest restriction site-associated DNA sequencing (ddRAD-seq) to resolve phylogenetic relationships among nine ecologically significant Rhododendron species (34 accessions) endemic to Zhejiang Province, China, a biodiversity hotspot for this genus. Using R. simsii as the reference genome, we generated 39.40 Gb of high-quality sequencing data with a Q30 score of 96.65% and a GC content of 39.63%, achieving an average alignment rate of 92.79%. Through stringent filtering (QD ≥ 2, MQ ≥ 40), we identified 14,048,702 genome-wide single nucleotide polymorphism (SNP), predominantly characterized by the mutation types T:A>C:G and C:G>T:A. The widespread R. simsii and R. simsii var. putuoense exhibited significant genetic diversity, whereas the low-altitude widespread R. molle and the endemic R. simiarum exhibited lower genetic diversity. Moderate genetic differentiation (Fst = 0.097) was observed between R. simsii and R. simsii var. putuoense, while substantial genetic differentiation was detected among the other Rhododendron species. Principal component analysis (PCA), combined with phylogenomic reconstruction, demonstrated that the Rhododendron genus can be stratified into six well-supported genetic clades. Furthermore, this study provides the first genomic validation of the sibling relationship between R. simsii and its variety, R. simsii var. putuoense, and clarifies the systematic position of R. huadingense, suggesting that it should be classified as a new subgenus. This study establishes ddRAD-seq as a cost-effective tool, providing both a theoretical framework for SNP-based phylogenetics and critical insights for conserving China's azalea biodiversity.

Phenotypic and Molecular Characterization of Multidrug-Resistant Clinical Isolates of the Candidozyma haemuli Species Complex (Formerly Candida haemulonii Species Complex) from the Brazilian Amazon Reveals the First Case of Candidozyma pseudohaemuli in Brazil.

This study included 24 isolates of the Candidozyma haemuli species complex from patients in the Brazilian Amazon between 2021 and 2024. These isolates were identified by sequencing as C. duobushaemuli (54.2%), C. haemuli sensu stricto (29.2%), C. haemuli var. vulneris (12.5%), and C. pseudohaemuli (4.2%). The finding of C. pseudohaemuli represents the first case reported in Brazil. Haplotype and phylogenetic analysis of these species, along with other isolates from Brazil, revealed low intraspecific genetic diversity. Resistance to at least one antifungal was observed in 83.3% of isolates, with multidrug resistance in 58.3%, including one isolate resistant to all tested antifungals. The isolates demonstrated active biofilm production, lytic enzyme activity, and thermotolerance. Notably, one C. duobushaemuli isolate exhibited tolerance to 42 °C, a phenotype not previously described. It is crucial for Brazil and other countries to recognize the emergence of these species as a public health threat and to take proactive measures to prevent outbreaks.

Genetic Diversity and Connectivity of Reef-Building Halimeda macroloba in the Indo-Pacific Region.

Understanding population genetic connectivity is crucial for the sustainability and persistence of marine biodiversity. As a fundamental reef-building macroalga of the coastal ecosystem, Halimeda macroloba Decaisne is one of the dominant intertidal seaweeds in the Indo-Pacific region. However, its genetic structure and population connectivity have been poorly recognized. Here, we explored the population genetic structure and genetic connectivity of H. macroloba using chloroplast tufA, rps3-rpl14, and rbcL. Our results indicated low genetic diversity and shallow population genetic structure at the intraspecific level, uncovering five genetic groups with six subdivided lineages in tufA and two genetic clusters in rps3-rpl14. We detected demographic expansion in the last glacial period of the Pleistocene and significantly asymmetric gene flow among different geographical units. We suggest that the southwestward ocean currents under the influence of northeast monsoon in the Indo-Pacific region are the main factor in shaping the present genetic structure, and the asexual reproduction of H. macroloba also plays an important role of the low genetic diversity pattern; in addition, the divergence between genetic clusters might be related to the historical isolation led by the paleoclimate oscillation in the Pleistocene. The Xisha Islands in the northern South China Sea might serve as a potential refugium of H. macroloba, which needs extra attention to conservation management. Given the limitation of sample size, we need to conduct more field work and carry out further research at a larger scale in the future. Our study provided new insights into the theory of population connectivity in the Indo-Pacific region and provided scientific basis for tropical costal seaweed conservation.

Genetic Diversity and Conservation of Bomarea ovallei (Phil.) Ravenna: Microsatellite Markers Reveal Population Vulnerability in the Atacama Desert.

The Atacama Desert, the driest and oldest desert on Earth, hosts a unique floral phenomenon known as the Desierto Florido (Flowering Desert), which occurs sporadically in response to rare rainfall events. Bomarea ovallei (Phil.) Ravenna is an endemic and endangered species of the Atacama Desert. However, its populations are geographically restricted and potentially vulnerable to genetic erosion due to isolation and extreme environmental conditions. This study aims to assess the genetic diversity of B. ovallei populations and develop microsatellite markers using next-generation sequencing (NGS) technology. A total of 268 microsatellite loci were identified, and 34 co-dominant markers were successfully developed for the first time in B. ovallei. Genetic diversity analysis using eight fluorescently labeled SSR markers revealed low genetic diversity across four populations, with the highest diversity observed in the QCA population, located within Llanos de Challe National Park, and the lowest in the TOTO population, which is highly exposed to anthropogenic activities. UPGMA and STRUCTURE analyses revealed three genetic clusters and high admixture among populations, suggesting historical or ongoing gene flow despite geographical separation. The presence of non-polymorphic loci and low PIC values in some markers further supports limited genetic variation. The newly developed microsatellite markers offer a valuable tool for future genetic studies, enabling the monitoring of genetic diversity and informing strategies for the preservation of this rare and ecologically significant species.

Genetic diversity and natural selection of Plasmodium falciparum Pf41 vaccine candidate in clinical isolates from Senegal

The merozoite surface antigen Pf41 was previously identified among the top 10 of new malaria vaccine candidates. Pf41 possesses red blood cell binding regions and conserved domains. We used population genetics approaches to determine the genetic diversity and to identify regions under balancing selection for the potential inclusion of Pf41 as candidate in a multicomponent vaccine. We screened 116 clinical isolates collected from different administrative regions in Senegal for P. falciparum positivity, Pf41 amplification and sequencing. We analyzed Pf41 sequences for polymorphism, natural selection, haplotype prevalence and linkage disequilibrium. Neutrality tests (Tajima’s D, FLD, FLF and MEME) were computed using DnaSP v6. and Datamonkey Hyphy. Population Analysis with Reticulate Trees (Popart) version 1.7 software was used to construct haplotypes network showing the distribution of haplotypes per study site. P. falciparum positivity from the 116 successfully tested samples was 93.1% of which 73 were successfully sequenced for Pf41. We found a low genetic diversity (π = 0.00144 ± 0.00022) and high haplotype diversity (Hd = 0.765 ± 0.037) of Pf41 sequences that can be attributed to linkage disequilibrium. We identified several substitutions under positive selection and negatively selected codons at inter-species level in the central and 6-Cys domains of Pf41, respectively. The predominant SNP S232R was found fixed by positive selection in Senegalese isolates. The genetic diversity of Pf41 antigen is low in clinical isolates from Senegal. With a central domain under balancing selection and two highly conserved 6-Cys domains under negative selection due to functional constraints, the Pf41 antigen appears as a good vaccine candidate. Further monitoring of allelic variants on larger and diverse sets of samples would justify the rational for functional assays and Pf41 integration in a multicomponent vaccine.

Ecological mechanisms of microbial assembly in clonal plant Glechoma longituba: from soil to endosphere.

Climate change presents significant challenges to plant growth and reproduction. Clonal plants, with low genetic diversity, are particularly vulnerable due to their limited adaptive capacity. Plant-associated microbiomes can play a crucial role in enhancing clonal plant survival and adaptability, yet the mechanisms governing microbial community assembly along the soil-episphere-endosphere continuum remain unclear. In this study, we investigated microbial community assembly patterns in the clonal plant Glechoma longituba. Our findings demonstrate that the assembly of microbial communities is primarily driven by host-related factors rather than external environmental filtering. First, host selection reduced α-diversity and network complexity while increasing β-diversity and community stability. Second, the mechanisms of microbial assembly transitioned from stochastic dominance in bulk soil and epiphytic compartments to deterministic processes within endophytic niches. Third, the taxonomic structure exhibited significant turnover along the soil-episphere-endosphere continuum, accompanied by functional redundancy to maintain ecosystem functions. The results support the hypothesis that host selection optimizes the functional composition of microbial communities by reducing diversity and network complexity while ensuring the stability of key functional microorganisms. The study emphasizes the critical role of host-microbe interactions in sustaining the adaptive and functional advantages of clonal plants, offering insights into managing sustainable plant communities under climate change.IMPORTANCEThis study highlights the vital role of plant-associated microbiomes in helping clonal plants, which have low genetic diversity, adapt to climate change. By examining the clonal plant Glechoma longituba, the research reveals that the plant itself plays a key role in shaping its microbial communities, rather than external environmental factors. Host selection simplifies microbial diversity and network complexity but enhances community stability and functional efficiency. These findings suggest that clonal plants can optimize their microbiomes to maintain critical functions. This work provides valuable insights into how plants and microbes interact to improve resilience, offering potential strategies for managing plant communities in a changing climate. By understanding these mechanisms, we can better support sustainable ecosystems and agricultural practices in the face of global environmental challenges.

RAD-Seq-derived SNPs reveal no local population structure in the commercially important deep-sea queen snapper (Etelis oculatus) in Puerto Rico

Abstract The queen snapper (Etelis oculatus Valenciennes in Cuvier & Valenciennes, 1828) is a deep-sea snapper whose commercial importance continues to increase in the US Caribbean. However, little is known about the biology and ecology of this species. In this study, the presence of a fine-scale population structure and genetic diversity of queen snapper from Puerto Rico was assessed through 16,188 SNPs derived from the Restriction site Associated DNA Sequencing (RAD-Seq) technique. Summary statistics estimated low genetic diversity (HO = 0.333–0.264) and did not reveal population differentiation within our samples (F ST = − 0.001–0.025). Principal component analysis and a model-based clustering method did not detect a fine-scale subpopulation structure among sampling sites, however, there was genetic variability within regions and sites. Our results have revealed comparable genetic and dispersal patterns to those observed in other shallow-water snapper species in Puerto Rico waters. It is crucial to further enhance our understanding of the ecological and biological aspect of the queen snapper to effectively manage and conserve this species as fishing pressure has been extended to deep water species in the US Caribbean.

The ecological niche and population history shape mosquito population genetics on a group of three Caribbean islands

BackgroundWhile studies on mosquito population genetics have primarily focused on medically relevant species, fewer have examined the genetic population structure of mosquitoes from a diverse range of species within a single geographical area. The limited comparison between native and non-native species, as well as ecologically divergent species from the same region, hampers our ability to generalise previously described patterns in mosquito population genetics. This study uses the mosquito fauna of the Caribbean islands of Aruba, Curaçao and Bonaire as a case study to explore population genetic variation among both native and non-native mosquito species, as well as among native species occupying different ecological niches. We examine how genetic patterns relate to their population history and species-specific ecologies.MethodsMitochondrial COII sequences were obtained from 258 mosquito specimens belonging to six species, occurring on all three islands. Sequences were used in haplotype network analysis to assess the genetic variation between mosquito populations of each of the six ecologically diverse species, which vary in both their population history and ecological niche.ResultsBoth the genetic diversity and population genetic structure were found to differ strongly between sets of species, leading to a subdivision into three species groups: (1) non-native species with low genetic diversity across all three investigated islands, (2) locally native species with high genetic diversity and closely related haplotypes occurring on different islands and (3) locally native species with high genetic diversity and locally restricted haplotypes.ConclusionsOur results show that the population genetics of non-native and native species strongly differ, likely as a result of population history. Furthermore, the results suggest that mosquito species sharing the same area may display distinct population genetic structure, likely related to differences in their ecology and dispersal capacity. We suggest that addressing a broader range of species within a single area will benefit future research on mosquito population genetics to place observed patterns into a broader historical, ecological and evolutionary context.Graphical

Unseasonal respiratory syncytial virus epidemics during the COVID-19 pandemic: Relationship between climatic factors and epidemic strain switching.

Unseasonal respiratory syncytial virus epidemics during the COVID-19 pandemic: Relationship between climatic factors and epidemic strain switching.

Genome-wide association study to identify the genomic loci associated with wheat heading date variation under autumn-sowing conditions.

The present study aimed to identify genetic loci associated with days to heading (DTH) in wheat under autumn-sowing conditions in Korea, where early heading is critical owing to the overlap between the wheat harvest and the rainy season. We evaluated 530 wheat core collections over five years, focusing on known heading date genes VRN-1 and PPD-1, and conducted a genome-wide association study (GWAS) to identify new genetic loci related to DTH. The results revealed that Korean accessions exhibited the earliest DTH, with modern Korean varieties heading even earlier, reflecting a strong breeding focus on early heading. Among the existing heading date genes, VRN-1 and PPD-D1 were significantly associated with DTH in the wheat core collection. However, all Korean varieties carried the same alleles for each of VRN-A1, PPD-A1, and PPD-D1, resulting in low genetic diversity, which rendered the existing heading date genes insufficient to fully account for the variation in DTH within the Korean varieties. GWAS identified nine single nucleotide polymorphisms (SNPs) associated with DTH in Group A (entire collection filtered, n=518) and six in Group B (accessions with genotypes identical to Korean varieties filtered, n=231). Four key SNPs (AX-95222044 and AX-94685526 in Group A, and AX-94550996 and AX-94970315 in Group B) were selected based on their effect sizes on DTH. In both groups, accessions with alleles for early heading at both of the selected SNPs exhibited the earliest DTH, advancing by 7.7 to 8.9 days. These findings suggest that the selected SNPs, particularly those reflecting the genotypes of Korean varieties, effectively explain the variations in DTH among Korean varieties and could enhance wheat breeding efficiency in Korea. Further research is needed to validate the four selected SNPs and identify the underlying genes, which could serve as valuable markers for developing early-heading wheat varieties suited to Korean autumn-sowing conditions.

Polymorphism analysis of GDF9 and BMP15 genes and their association with litter size in crossbreed goats in Malaysia.

The goat industry plays a crucial role in Malaysia's economy, with breeds such as Katjang and Boer being integral to the chevon supply. However, achieving self-sufficiency in goat meat production is still challenging due to the insufficient local carcass supply. To address this issue, a crossbreeding program has been initiated to improve reproductive performance in local breeds. In mammals, there are BMP15 and GDF9 genes, which are the components of the TGF-β superfamily that are key regulators of ovulation and litter size. This study aimed to improve reproductive performance in crossbred goats from Katjang and Boer populations in Sabah, Malaysia, by analyzing genetic variations in the BMP15 and GDF9 genes. A total of sixty female cross-Katjang goats, with recorded litter size and parities, were sampled. Five milliliters of blood was taken from the jugular vein using K2-EDTA tubes. Genetic analysis was performed using conventional PCR at the Biotechnology Research Institute, University Malaysia Sabah, followed by sequencing at Apical Scientific, Malaysia. Four novel polymorphic loci were identified within the GDF9 gene: G320C, A352G, G366T, and G375T. All of these loci resulted in missense mutations, causing a change in amino acid sequences. Notably, the A352G and G375T loci showed significant associations with litter size, with the AG genotype at position 352 and the GG genotype at position 375 emerging as potential markers for selective breeding. However, the polymorphic information content (PIC)values indicated low genetic diversity (< 0.25) at these loci. Interestingly, no polymorphisms were detected in the BMP15 gene, suggesting a monomorphic state (wild-type genotype) in the Cross-Katjang goat population. This finding indicates that BMP15 may not play a significant role in litter size variation in this crossbreed, shifting the focus towards GDF9 as a more relevant genetic marker for enhancing reproductive traits. This study provides important insights into the genetic factors influencing reproductive traits in crossbred goats, with potential applications in marker-assisted selection to improve reproductive and productivity performance.

Exploring the genetic diversity and population structure of little-pod false flax (Camelina microcarpa: Brassicaceae) in Ukraine

Taxa of the genus Camelina faced numerous hybridization and allopolyploidy events during their evolutionary history. Little-pod false flax, C. microcarpa, a direct wild progenitor of the cultivated oilseed crop C. sativa, is one of the most widespread representatives of the genus. Due to several genetic bottleneck events and subsequent domestication, C. sativa now exhibits low genetic diversity, which significantly complicates its breeding. Camelina microcarpa wild germplasm seems to be a valuable pool of genetic diversity that could be effectively used for gene introgression in C. sativa and overcoming its genetic paucity. However, the genetic diversity and population structure of C. microcarpa remain insufficiently understood, particularly in Ukraine, which is considered among Camelina’s genetic diversity hotspots. Here, we used a combination of TBP/cTBP and SSR markers to assess the genetic diversity and population structure of C. microcarpa in Ukraine and partially in adjacent Western European regions. Three distinct genetic populations have been identified: Southern Ukrainian (predominantly occurring in the Steppe zone), Northwestern Ukrainian (occurring in the Forest-Steppe zone and Precarpathian region, particularly in Lviv Region), and Western European (Poland, Hungary, Germany). Our findings suggest that the Southern Ukrainian population exhibits the highest genetic diversity, possibly representing an ancestral gene pool, while the Northwestern Ukrainian and Western European populations demonstrate evidence of a high gene flow with the Southern Ukrainian population of C. microcarpa. Our phylogenetic analysis confirmed strong differentiation of these three populations, while the population structure analysis further indicated a high rate of admixtures between the populations. These findings enhance our under­standing of the evolutionary relationships and geographic distribution of C. microcarpa. The observed high heterozygosity and complex population structure highlight the potential of C. microcarpa (especially the Southern Ukrainian population) to be used as a germplasm donor for C. sativa breeding programs. Our study provides new insights into hexaploid Camelina species evolution and genetic diversity, establishing foundations for future development of wild germplasm utilization strategies and cultivated false flax breeding improvement.

High-Throughput Sequencing Reveals Apple Virome Diversity and Novel Viruses in the Czech Republic.

Apple viruses pose significant threat to global apple production. In this study, HTS technology was used to investigate the apple virome in the Czech Republic. Previously reported viruses, including ACLSV, ASPV, ASGV, ApMV, AGCaV, and CCGaV, were confirmed, and near-complete genomes were assembled. Additionally, two novel viruses, ARWV1 and ARWV2 were identified for the first time in the Czech Republic. Phylogenetic analyses showed low genetic variability among ARWV2 isolates, suggesting a possible recent introduction or limited diversification. In contrast, ARWV1 isolates displayed distinct clustering in the coat protein coding region, separating symptomatic and asymptomatic samples, indicating a potential involvement of genetic determinants in symptom expression. Mixed infections were prevalent, with multiple molecular variants of ACLSV, ASPV, and AGCaV detected within individual samples, along with co-infections involving viruses from different families. Recombination analysis identified frequent recombination events in ACLSV and ASPV, often involving non-apple parental sequences, suggesting their potential for cross-host infections. Additionally, an interspecific recombination event was detected in an almond ApMV isolate, with PNRSV as a minor parent. These findings highlight the impact of agricultural practices on viral evolution and host adaptation. This study demonstrates the utility of HTS as a powerful tool for uncovering viral diversity, recombination events, and evolutionary dynamics.

Genetic diversity analysis and conservation strategy recommendations for ex situ conservation of Cupressus chengiana

BackgroundCupressus chengiana is mainly distributed in the Hengduan Mountains area in China. It is one of the Class II endangered plants, ex situ conservation is often used to the affected C. chengiana population due to the construction of the power station. However, population fragmentation and inbreeding in the ex situ conservation have led to decline in genetic diversity. It is therefore important to clarify the differences in genetic diversity between native populations and ex situ population.ResultsIn this study, we used Genotyping-by-Sequencing to assess the genetic diversity of 30 C. chengiana trees from four populations in the Dadu River Basin, southwest China, including one ex situ conserved population (DK) and three native populations (BW, SA, RJ). The results showed that compared with the native populations, the DK population showed higher genetic diversity. Among the three native populations, SA population may experience inbreeding and has low genetic diversity. The population structure analysis further revealed that the DK population had higher gene flow and lower differentiation than other three populations. For ex situ populations, the primary determinant of genetic diversity is the genetic variation present in the seedlings sourced from natural populations.ConclusionThese findings support the feasibility of ex situ conservation for C. chengiana conservation. This study provides a scientific foundation for the preservation, management, and restoration of C. chengiana, and would offer valuable insights for the conservation of other endangered plants.

Genetic diversity and nutritional analysis of sweet potato [Ipomoea batatas (l.) Lam.] genotypes in Abakaliki, Nigeria

BackgroundSweet potato is an important root crop cultivated in different countries of the world. Its production and productivity are limited by factors such as the use of unimproved local varieties, pests, disease, and drought. To overcome these constraints, diversity in sweet potato genotypes could be a prerequisite for breeding programs. The present study aimed to determine the genetic diversity and nutritional composition of sweet potato accessions. One hundred accessions of sweet potato were collected from Nigeria and Niger for agro-morphological characterization and 50 of them were used for nutritional and molecular analysis. Eleven quantitative traits, six nutritional traits, and ten SSR markers were used for diversity analysis.ResultsAnalysis of variance (ANOVA) revealed significant differences (p < 0.01) among the sweet potato varieties for all the agro-morphological and nutritional traits studied. Accessions with orange flesh color had higher beta-carotene content compared to those with white, cream, and yellow flesh color. From the molecular diversity analysis, a total of 20 alleles were detected in 50 sweet potato accessions using 10 SSR markers. The average values for Na, Ne, I, Ho, He, and PIC were 2, 1.62, 0.55, 0.40, 0.37, and 0.30 respectively. Cluster analysis based on dissimilarity matrix grouped the accessions into two major clusters. Analysis of molecular variance (AMOVA) revealed 11% variation among the populations and 89% variation within the population, indicating low genetic variation among the populations and high genetic variation within population at p < 0.001.ConclusionOverall, variability was observed among the studied sweet potato accessions based on agro-morphological, nutritional traits and the SSR markers used. This will help breeding in using these genotypes for further improvement of the studied traits.

Genetic Diversity and Population Structure in Farmed and Wild Pacific Oysters (Crassostrea gigas): A Comparative Study.

The Pacific oyster, Crassostrea gigas, is an important commercially farmed species in Korea. C. gigas exhibits low genetic diversity in wild populations in Korea. To address this, we bred Japanese broodstock for more than five generations and released them into two populations to increase genetic diversity. We also assessed whether this improvement was achieved by comparing them with a control population. In this study, we analyzed genetic diversity using 16 microsatellite loci of C. gigas. The observed heterozygosity HO in the farmed population ranged up to 0.494, while in the wild population, it was 0.437. The farmed population had the highest genetic diversity, but the effective population size was low (105). The PD population size for resource creation was 403, which was higher than that of GH. The genetic structure was divided into two groups with K = 2. The first group consisted of the BR population, while the second group included the GH, GW, and PD populations. Therefore, we confirmed significant genetic differences between the farmed, wild, and resource creation populations. This study provides essential genetic information for future fishery resource development and conservation of C. gigas.