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Latin Americans are underrepresented in genetic studies, increasing disparities in personalized genomic medicine. Despite available genetic data from thousands of Latin Americans, accessing and navigating the bureaucratic hurdles for consent or access remains challenging. To address this, we introduce the Genetics of Latin American Diversity (GLAD) Project, compiling genome-wide information from 53,738 Latin Americans across 39 studies representing 46 geographical regions. Through GLAD, we identified heterogeneous ancestry composition and recent gene flow across the Americas. Additionally, we developed GLAD-match, a simulated annealing-based algorithm, to match the genetic background of external samples to our database, sharing summary statistics (i.e., allele and haplotype frequencies) without transferring individual-level genotypes. Finally, we demonstrate the potential of GLAD as a critical resource for evaluating statistical genetic software in the presence of admixture. By providing this resource, we promote genomic research in Latin Americans and contribute to the promises of personalized medicine to more people.

Cowpea is a highly drought-adapted leguminous crop with great promise for improving agricultural sustainability and food security. Here, we report analyses derived from array-based genotyping of 2,021 accessions constituting a core subset of the worlds largest cowpea collection, held at the International Institute of Tropical Agriculture (IITA) in Ibadan, Nigeria. We used this dataset to examine genetic variation and population structure in worldwide cowpea. We confirm that the primary pattern of population structure is two geographically defined subpopulations originating in West and East Africa, respectively, and that population structure is associated with shifts in phenotypic distribution. Furthermore, we establish the cowpea core collection as a resource for genome-wide association studies by mapping the genetic basis of several phenotypes, with a focus on seed coat pigmentation patterning and color. We anticipate that the genotyped IITA Cowpea Core Collection will serve as a powerful tool for mapping complex traits, facilitating the acceleration of breeding programs to enhance the resilience of this crop in the face of rapid global climate change.

Desertification is a major threat to biodiversity in arid areas of the world, partly because many organisms in these regions already exist at or near the limits of their movement and physiology. Here, we used molecular data to investigate patterns of persistence and dispersal in an ecologically and economically important carpenter bee (Xylocopa grisescens Lepeletier) found throughout the semiarid Caatinga region of Brazil. We used a genome-wide approach (double digest restriction-site associated DNA, ddRAD) to gather genetic data from bees sampled from eight sites within a semiarid region subject to desertification in Northeastern Brazil. Across all populations, we observed a consistent heterozygosity and effective population size deficit along with low genetic differentiation. We did not find strong evidence of dispersal limitations caused by desertification in this study system despite data collection from sites up to 300 km distant. Thus, our data suggest that human-mediated changes in the Caatinga, such as habitat loss, have impacted the population genetic patterns of X. grisescens. However, these impacts have also been softened by the species' biological characteristics, such as its relatively high capacity for movement. This study provides insights into how habitat changes might impact the long-term survival of large solitary bees.

Numerous individuals of an amphipod previously unreported from the Black Sea were found in 2017 on structures of a mussel and oyster marine farm, near the outer roadstead of Sevastopol Bay, Crimea. The species discovered was morphologically especially similar to Stenothoe tergestina (Nebeski 1881) and provisionally identified as Stenothoe cf. tergestina. The morphology, population structure, and ecology of this species were studied. An analysis of the population structure of S. cf. tergestina in the years 2017–2022 showed that adult females, males, and juveniles were present in the samples year round. The animals preferred to dwell on surfaces overgrown with periphyton colonies of the hydroid polyp of the genus Aglaophenia Lamouroux 1812. In the collections of amphipods from the periphyton of the farm structures, S. cf. tergestina turned out to be the most abundant (70–90% of the total number of identified amphipod individuals). The length of adult females was up to 4.5 mm, while it reached up to 3.6 mm in males. [ABSTRACT FROM AUTHOR]

Background: Garlic (Allium sativum L.) is an important crop with significant medicinal and culinary uses. Understanding the genetic diversity and population structure of Himalayan garlic genotypes from Sikkim is crucial for effective breeding and conservation efforts. This study aims to analyze the genetic diversity among 60 Himalayan garlic genotypes collected from various altitudinal locations of Sikkim, India, using 27 Simple Sequence Repeats (SSR) markers. Methods and results: The genetic diversity was assessed using SSR markers, which revealed substantial variation among the genotypes. The number of alleles (Na) ranged from 1.13 to 2.00, while the major allele frequency (MAF) varied from 0.672 to 0.963. The observed heterozygosity (Ho) ranged from 0.0667 to 0.475, indicating moderate genetic diversity. Population structure analysis using STRUCTURE software grouped the genotypes into three distinct sub-populations, suggesting genetic differentiation not solely based on leaf morphology. Analysis of Molecular Variance (AMOVA) showed that genetic variation was more significant among individuals within populations (41%) than among populations (16%). UPGMA dendrogram and Principal Coordinates Analysis (PCoA) further confirmed the genetic relationships among the genotypes. Conclusions: This study reveals significant genetic diversity among Himalayan garlic genotypes from Sikkim, with clear genetic differentiation observed within and between populations. The results highlight the importance of both leaf morphology types and genetic structure in understanding the genetic basis of phenotypic variation in garlic. The finding provides valuable insights for future breeding programs and conservation strategies, emphasizing the need to consider morphological and genetic data for effective germplasm management and improvement of garlic cultivars. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the relationship among Lithuanian, Latvian, Indian, and some other populations through a genome-wide data analysis of single nucleotide polymorphisms (SNPs). Limited data of Baltic populations were mostly compared with geographically closer modern and ancient populations in the past, but no previous investigation has explored their genetic relationships with distant populations, like the ones of India, in detail. To address this, we collected and merged genome-wide SNP data from diverse publicly available sources to create a comprehensive dataset with a substantial sample size especially from Lithuanians and Latvians. Principal component analysis (PCA) and admixture analysis methods were employed to assess the genetic structure and relationship among the populations under investigation. Additionally, we estimated an effective population size (Ne) and divergence time to shed light on potential past events between the Baltic and Indian populations. To gain a broader perspective, we also incorporated ancient and modern populations from different continents into our analyses. Our findings revealed that the Balts, unsurprisingly, have a closer genetic affinity with individuals from Indian population who speak Indo-European languages, compared to other Indian linguistic groups (such as speakers of Dravidian, Austroasiatic, and Sino-Tibetan languages). However, when compared to other populations from the European continent, which also speak Indo-European and some Uralic languages, the Balts did not exhibit a stronger resemblance to Indo-European-speaking Indians. In conclusion, this study provides an overview of the genetic relationship and structure of the populations investigated, along with insights into their divergence times. [ABSTRACT FROM AUTHOR]

The present study aimed to evaluate the genetic diversity and differentiation of Pinus nigra Arnold, the European black pine, populations located in protected forested areas in three countries from the Balkan and Mediterranean region: Bulgaria, Greece, and Cyprus. Totally, 175 DNA samples from P. nigra plants collected from eight populations in these countries were analyzed using three SRAP primer pairs. The applied SRAP markers demonstrated high-resolution power, resulting in the identification of an average of 215 ± 67 polymorphic loci per SRAP primer pair. The analysis of molecular variance (AMOVA) showed that 82% of the observed variation was due to intra-population variation, while 18% was due to inter-population variation. The overall analysis of the population structure suggested low (Fst ≤ 0.01) intra-country differentiation for the populations from Bulgaria and Cyprus and moderate (0.15 ≤ Fst ≤ 0.17) inter-country differentiation. On the contrary, high differentiation between the populations (0.06 ≤ Fst ≤ 0.20) and complex genetic structure were characteristic of the three populations from Greece, relatively closely located in the area of the Pindos National Park. Analysis of the population structure also revealed that one of the Pindos populations belonged to the cluster of Bulgarian populations (Fst ≤ 0.01), showing moderate (Fst ≤ 0.11) to high (Fst ≤ 0.20) genetic differentiation from the other analyzed Pindos populations. The further use of SRAP markers for mapping the genetic diversity among P. nigra populations and identification of local populations diverted from the overall phylogeography-driven pattern in the studied region are discussed. [ABSTRACT FROM AUTHOR]

Understanding the genetic diversity of crops is of fundamental importance for the efficient use and improvement of germplasm resources. Different molecular genotyping systems have been implemented for population structure and phylogenetic relationships analyses, among which, microsatellites (SSRs) and single nucleotide polymorphisms (SNPs) markers have been the most widely used. This study reports the efficacy of SNPs detected via double-digest restriction-site-associated DNA sequencing (ddRADseq) and SSRs analyzed via capillary electrophoresis (CE) and high-resolution melting (HRM) in tomato. In total, 21,020 high-quality SNPs, 20 CE-SSRs, and 17 HRM-SSR markers were assayed in a panel of 72 accessions that included a diversified set of landraces, long-shelf-life cultivars and heirlooms with different origins and fruit typology. The results showed how the population structure analysis was consistent using the three genotyping methods, although SNPs were more efficient in distinguishing cultivar types and in measuring the degree of accessions' similarity. Compared to CE-SSR, the analysis of microsatellites via HRM yielded a slightly higher number of alleles (98 vs. 96). HRM-SSR demonstrated a distinction between European and non-European germplasm, better resolving the collection's diversity and being more consistent with SNP data. Phylogenetic trees drawn with independent marker data, detected specific groups of accessions showing robust clusters, highlighting how heirlooms were less heterogeneous than landraces. In addition, the fixation index (FST) revealed a high genetic differentiation between heirlooms and long-shelf-life cultivars, with SNP and SSR-HRM data emphasizing the distinction between cherry and plum types and CE-SSR data between cherry and oxheart types. In all instances, a greater molecular variance was found within the different considered biological statuses, provenances, and typologies rather than among them. This work presents the first attempt to compare the three tomato genotyping techniques in tomato. Findings highlighted how the markers used are complementary for genetic diversity analysis, with SNPs providing better insight and HRM-SSR as a viable alternative to capillary electrophoresis to dissect the genetic structure. [ABSTRACT FROM AUTHOR]

Rice blast disease is one of the most disastrous diseases causing significant losses to the crop. In the humid weather conditions of north-eastern Himalayan region, the situation is highly devastating as the climate is very favorable to the fungus Magnaporthe oryzae. Development of resistant rice varieties is the most effective, economical, and environment-friendly way to control this disease. The study aimed to identify novel sources of resistant donor using agro-morphological and gene-based markers for their utilization in development of blast-resistant varieties with high yield potential. Phenotypic evaluation has classified the hundred landraces into resistant (13), moderately resistant (43), moderately susceptible (24), and susceptible (20). Fifty-nine genotypes were found to carry genes responsible for blast resistance, either singly or in combination. The genotype MN-62 was found to have a blast score of zero in field screening. The genetic frequencies of the major blast resistance genes ranged from 28 to 97%. The cluster analysis grouped the landraces into three major groups. Additionally, the association between blast genes was computed with blast score using a general linear model (GLM) and mixed linear model (MLM), revealing that the markers AP4007, AP56595, C1454, and RM208 were found to be associated with the trait. The landraces with six blast R-genes like Nungshang Phou, Ratkhara, Anandhi, RCPL 1–44, Ching Phou Khong Nombi, MN-31, Rona Yang, and RCPL-128 were also superior for agro-morphological traits. Similarly, the landraces MN-62, Tara Bali, Rato Bhan Joha, MN-47, RCPL 1–411, and CAU-R1 were promising regarding yield and blast resistance. The resistant lines with various combinations of blast resistance genes can be utilized for introgression of genes into the commercial varieties for durable resistance using marker-assisted backcrossing. [ABSTRACT FROM AUTHOR]

Population structure of Cannabis sativa L. was explored across nine independent collections that each contained a unique sampling of varieties. Hierarchical Clustering of Principal Components (HCPC) identified a range of three to seven genetic clusters across datasets with inconsistent structure based on use type indicating the importance of sampling particularly when there is limited passport data. There was broader genetic diversity in modern cultivars relative to landraces. Further, in a subset of geo-referenced landrace accessions, population structure was observed based on geography. The inconsistent structure across different collections shows the complexity within Cannabis, and the importance of understanding any particular collection which could then be leveraged in breeding programs for future crop improvement. [ABSTRACT FROM AUTHOR]

For wheat improvement, knowledge of diversity patterns and evolutionary relationships among the germplasm is essential for the sustainable conservation of valuable genetic materials. Therefore, this investigation aims to decipher the genetic diversity and population structure of wheat germplasm and identify diverse accessions to expedite the wheat breeding programs. In this study, a diverse set of 81 bread wheat genotypes, including derived doubled haploids, elite exotic lines, indigenous landraces and cultivars were used. Phenotypic and molecular characterization was conducted using 10 morpho-physiological traits and 68 microsatellite (SSR) markers, respectively. Among, the nine morphological descriptors the highest morphological variation (H) was observed for 1000 grain weight (1.06). The genotypes based on phenotypic traits were grouped into three clusters using Euclidian distance. Principal component analysis (PCA), revealed that the first four significant principal components accounted for 78% of the variance. A total of 58 alleles were generated from 27 polymorphic SSR primers with an average of 2.15 alleles per locus. The polymorphic information content (PIC) ranged from 0.26 (Wmc434) to 0.76 (Wmc47), with an average of 0.69. Molecular analyses by NTSYS-PC delineated the genotypes into four clusters, whereas while the cluster tree generated using neighbour-joining analysis identified three major clusters. Structure analysis grouped the genotypes into three sub-populations. When comparing agro-morphological and molecular clusters, seven genotypes (DH 194, DH 207, DH 215, DH 217, CIMMYT line 30 Entry No.10, Chamba landrace 18 and C 306) were identified as common. Notably, these genotypes were identified as distant and belong to different diversity clusters. Therefore, integrating morphological analysis with a polymorphic SSR survey may be effective in selecting diverse parental lines in wheat hybridization programs. [ABSTRACT FROM AUTHOR]

Papaya (Carica papaya L.) is a versatile tropical fruit crop with economic and nutritional benefits. Assessing genetic diversity of the germplasm is essential for effective collection, conservation management and utilization of resources for breeding purposes. Genetic variability and population structure were studied for 55 papaya accessions including landraces, cultivars, and exotic collections, using 15 simple sequence repeat (SSR) markers. SSR analysis data revealed a total of 95 alleles with an average of 6.3 alleles per marker and an average heterozygosity of 0.75. All the markers were polymorphic, with an average PIC value of 0.72. The unweighted pair group method with arithmetic mean (UPGMA) dendrogram based on shared allele distance grouped the accessions into four main clusters. Genetic structure based on the structure algorithm identified two populations, whereas discriminant analysis of principal components revealed four distinct genetic clusters. Remarkably, these clusters were not linked to the geographic regions. The analysis of molecular variance (AMOVA) indicated a variation of 75% within individuals and 22% between populations. Fst = 0.216 and Nm = 0.205 showed moderate genetic relationship within populations. These findings have implications for marker-assisted breeding, improvement of conservation strategies, detection of duplicates, and framing policies for sustainable crop utilization. [ABSTRACT FROM AUTHOR]

Sweetpotato (Ipomoea batatas (L.) Lam), a vital root crop cultivated globally by small and marginal farmers, plays a pivotal role in combatting malnutrition and serves as a lifeline for underdeveloped nations. In order to optimize the utilization of germplasm for breeding purposes, it is crucial to comprehend the extent of genetic diversity it encompasses. The effective utilization of genetic diversity in germplasm resources hinges on assessing genetic relationships among diverse cultivars and landraces, facilitating improved breeding programs and sustainable agricultural practices. In this study, 31 sweetpotato genotypes were examined to assess genetic diversity using 21 simple sequence repeat (SSR) markers. A total of 704 amplicons were detected, averaging 33.52 per marker. Band frequency ranged from 0.33 to 0.69, while polymorphic information content ranged from 0.03 to 0.61. Utilizing the Dice similarity coefficient, the 31 genotypes were clustered into three primary clusters, demonstrating similarity scores from 0.09 to 0.92. Subsequent subdivision of these clusters revealed nuanced relationships within the dataset. Population structure analysis uncovered two well-stratified subpopulations, Subpop1 and Subpop2, with Fst values of 0.49 and 0.23, respectively. Average distances within Subpop1 and Subpop2 were 0.26 and 0.33, and the estimated allele-frequency divergence was 0.21. The SSR markers utilized in this study proved to be informative and polymorphic, offering insights into the genetic diversity of sweetpotato. These markers hold significant potential for enhancing breeding programs aimed at improving elite progenies in the future. [ABSTRACT FROM AUTHOR]

Quercus brantii var. persica and Quercus infectoria are two economically and ecologically important oak species widespread in the Zagros forest, located in the northwestern and southwestern parts of Iran. An effective study of the genetic diversity and population structure of these genetic resources is still unexplored. In the present study, 48 accessions of the mentioned oak species collected from different regions of Kermanshah province were subjected to a study of genetic diversity and population structure using two sets of markers (inter-simple sequence repeats [ISSR] and CAAT-box derived polymorphism [CBDP]). CBDP markers showed greater efficiency in detecting polymorphism in the oak individuals studied. The analysis of molecular variance [AMOVA] showed that the genetic variation within species, as well as within regions per species, was higher than between species. Quercus brantii var. persica had the highest values for all indicators of genetic variability. Moreover, at the regional level, the Dalahoo populations in both species showed the highest genetic diversity using the ISSR markers. This population, along with Gilan-e-Gharb had the highest genetic diversity using the CBDP markers. The results indicate a high level of genetic diversity in isolated regions, which in turn promotes the formation of population structure. Therefore, this may contribute to further conservation and genetic improvement of Iranian oak germplasm. [ABSTRACT FROM AUTHOR]

Biological invasions are a growing threat to native ecosystems, and genomic studies have become an increasingly useful tool for invasive species management by providing the ability to identify spatial population structure in the invaded range. In this study, we compared the spatial genetic structure of two ecologically distinct non-native lizard species both established and widespread throughout South Florida, a global hotspot for reptile invasions. We used an individual-based sampling approach to collect genetic samples of Agama picticauda, a rock specialist native to West Africa, and Basiliscus vittatus, a riparian specialist from Central and South America. We collected specimens across Miami-Dade County (the original site of introduction) and then genotyped ~ 4000 single nucleotide polymorphisms for each species. Both species exhibited fine-scale population structure at distances < 5 km for A. picticauda and < 10 km for B. vitattus, but at the county scale B. vittatus showed much stronger spatial structure compared to A. picticauda. Landscape genomic analysis revealed no significant landscape influence on A. picticauda genetic differentiation, while for B. vittatus low canopy cover was the best predictor of genetic connectivity. The genetic structure of both species may suggest human-aided dispersal is driving long distance movements, and A. picticauda appear more susceptible to these events likely due to their affinity for highly urbanized areas. By identifying variable dispersal patterns among two ecologically distinct species, we hope that this study will help combat the spread of these or similar species as they continue to arrive at urban centers across the globe. [ABSTRACT FROM AUTHOR]

Reductions in gene flow due to anthropogenic habitat fragmentation are often associated with reduced genetic diversity and increased population structuring in wildlife populations. We assessed fine-scale population structure and landscape factors influencing gene flow in threatened boreal woodland caribou (Rangifer tarandus caribou) based on genotypes for 337 individuals sampled at the southern extent of their distribution in Ontario. The impact of isolation by distance (IBD) and isolation by resistance (IBR) on gene flow was examined using resistance surface optimization and linear mixed-effects modelling. Genetic clustering algorithms failed to identify a biologically meaningful pattern of population substructure, consistent with the observed weak genetic differentiation of individuals across the study area. Although the inferred optimum resistance scenario differed based on the choice of genetic distance metric, roads were consistently included in the top resistance models. While our results support a growing body of evidence indicating a negative influence of roads on gene flow in woodland caribou, future studies are recommended to validate these finding given the conservation implications for this iconic boreal species. [ABSTRACT FROM AUTHOR]

Biologists currently have an assortment of high-throughput sequencing techniques allowing the study of population dynamics in increasing detail. The utility of genetic estimates depends on their ability to recover meaningful approximations while filtering out noise produced by artifacts. In this study, we empirically compared the congruence of two reduced representation approaches (genotyping-by-sequencing, GBS, and whole-exome sequencing, WES) in estimating genetic diversity and population structure using SNP markers typed in a small number of wild jaguar (Panthera onca) samples from South America. Due to its targeted nature, WES allowed for a more straightforward reconstruction of loci compared to GBS, facilitating the identification of true polymorphisms across individuals. We therefore used WES-derived metrics as a benchmark against which GBS-derived indicators were compared, adjusting parameters for locus assembly and SNP filtering in the latter. We observed significant variation in SNP call rates across samples in GBS datasets, leading to a recurrent miscalling of heterozygous sites. This issue was further amplified by small sample sizes, ultimately impacting the consistency of summary statistics between genotyping methods. Recognizing that the genetic markers obtained from GBS and WES are intrinsically different due to varying evolutionary pressures, particularly selection, we consider that our empirical comparison offers valuable insights and highlights critical considerations for estimating population genetic attributes using reduced representation datasets. Our results emphasize the critical need for careful evaluation of missing data and stringent filtering to achieve reliable estimates of genetic diversity and differentiation in elusive wildlife species. [ABSTRACT FROM AUTHOR]

Indigenous landraces are heterogeneous and exhibit greater gene diversity, and are therefore an excellent source of variation and material for crop improvement. However, they are very prone to genetic erosion, therefore exploration of genetic variability in landraces is essential step for crop breeding. Discovery of the genetics of a character in rice, that cope adverse condition, is important for maintaining world-food supply. In this study, fifty rice genotypes were assessed for the phenotypic and genetic diversity and their relatedness using morpho-physiological traits of the genotypes. Further clustering and population structure analysis were performed using phenotypic and simple sequence repeat (SSR) markers data through unweighted pair group method with arithmetic mean (UPGMA) and STRUCTURE analysis. Significant variation among yield components were identified. Phenotypic and genotypic coefficients of variability were higher for filled grains, whereas heritability was highest for plant height. Panicle number and 100-grain weight displayed significant relationship with yield. Phylogenetic clustering of the agromorphological traits divided the genotypes into eight clusters, whereas SSR markers yielded ten clusters. SSR markers produced a total of 138 alleles varying from two to nine with 77.53% polymorphic allele having 3.69 alleles per locus (average). The polymorphic information content indices and observed number of alleles varied among markers with an average of 0.649, exhibiting RM336, RM316, and RM287 have the greatest potentiality in exploring genetic diversity among genotypes. Among the genotypes, Dolkochu, Jolduba, BRRI Dhan-32, and Mokbul displayed significant variability, suggesting their suitability as potential parents in hybridization programs. Population structure study demonstrated that the genotypes were structurally diverse that grouped the accessions into two subpopulations (K = 2). Therefore, this research aimed to identify potential genotypes and suitable traits of rice germplasms for breeding programs. [ABSTRACT FROM AUTHOR]

Cockchafers Melolontha spp. are polyphagous root pests and outbreak species of considerable economic importance to forestry in Europe. Knowledge of genetic diversity within and between cockchafer populations is largely unexplored but could lead to more effective monitoring and management strategies of these pests. In this study, we fill several gaps in the knowledge of the genetic population structure of Melolontha melolontha and Melolontha hippocastani. Using microsatellite loci and over 200 individuals per species, we examined the genetic structure of Melolontha spp. populations collected from three primary outbreak areas in central and southeastern Poland. We demonstrated that our focal species share some common genetic patterns, such as considerable genetic diversity within subpopulations (within sampling sites) with minor effects of past bottlenecks possibly masked by current population sizes. The estimates of effective population sizes, although subject to wide credibility intervals, indicated a large number of individuals contributing to further generations of the population. The migration rates exceed the threshold of one per generation required for gene flow and maintenance of population equilibrium, indicating limited impact from forest management practices on either cockchafer species. While genetic differentiation was observed in M. melolontha populations, supported by various indices (fixation index, principal coordinate analysis, assignment tests), the M. hippocastani populations were genetically similar. This disparity may hint at the potential historical divergence between these species. In this aspect, more detailed phylogeographic and population genetic studies covering a large area of the Palaearctic distributions of both species are required. Our findings constitute one of the initial efforts aimed at delineating the genetic diversity, differentiation, population structure, gene flow, and migration patterns within Melolontha spp. This exploration is especially significant for M. hippocastani , given its completely unexplored genetic population structure. [ABSTRACT FROM AUTHOR]

The article discusses the impact of population size, structure, fertilization success, and propagule dimorphism on sex allocation in simultaneous hermaphrodites, focusing on plant reproduction. The authors present a mathematical model that challenges classical sex allocation theory by showing that population size, pollen mortality, and fertilization success can influence sex allocation. The study reanalyzes the model and confirms the classical result of equal sex allocation under panmixia. The research highlights the importance of considering population structure and dispersal rates in understanding sex allocation evolution. [Extracted from the article]

Background: Avocado, a fruit crop renowned for its high nutritional value, has seen a steadily increasing market demand. However, breeding efforts for avocados have lagged those for other commercial fruits due to limited genomic research and germplasm resources. To address this shortfall, a genome-wide association study was conducted on 122 avocado accessions from the United States Department of Agriculture (USDA) Agricultural Research Service (ARS) Subtropical Horticultural Research Station (SHRS) germplasm collection. The study aimed to identify genetic markers and regions associated with various morphometric traits in avocado fruits, including fruit weight, length, width, diameter, seed weight, seed length, seed width, fruit seed ratio (FSR), and fruit shape index (FSI). Results: Leveraging 4,226 high-quality single nucleotide polymorphism (SNP) markers obtained from genotyping arrays, fifteen markers were identified with strong associations with these traits, utilizing Bayesian-information and Linkage-disequilibrium Iteratively Nested Keyway (BLINK) and Fixed and random model Circulating Probability Unification (FarmCPU) models. Gene annotation analyses within a 200-kb window in the vicinity of significant SNPs revealed several genes associated with various metabolic pathways suggesting that some of them likely determine these fruit quality traits, which needs to be verified and validated. Our results, which were conducted at one location, provide directions for conducting future studies using high-resolution genotyping and long-term multi-year and multi-location trait evaluations for precisely identifying the causal SNP(s) and genes associated with these traits. Conclusions: These markers reported in this manuscript provide valuable tools for applying marker-assisted selection (MAS) in avocado breeding programs aimed at enhancing fruit quality and value. [ABSTRACT FROM AUTHOR]

Comprehensive characterizations of genetic diversity and demographic models of ethnolinguistically diverse Chinese populations are essential for elucidating their forensic characteristics and evolutionary past. We developed a 114-plex NGS InDel panel to genotype 114 genome-wide markers and investigated the genetic structures of Zhuang, Hui, Miao, Li, Tibetan, Yi, and Mongolian populations, encompassing five language families. This panel demonstrated robust performance, with exceptional potential for forensic individual identification and paternity testing, evidenced by the combined power of discrimination for 77 autosomal InDels (ranged from 1-3.6400 × 10–30 to 1-3.5713 × 10–32) and the combined power of exclusion (ranged from 1-2.1863 × 10–6 to 1-2.1261 × 10–7). The cumulative mean exclusion chance for 32 X-chromosomal InDels varied between 0.99996 and 0.99999 for trios and 0.99760 to 0.99898 for duos. We also analyzed genetic similarities and differences between these populations and 27 global populations, revealing distinct clusters among African, South Asian, East Asian, and European groups, with a close genetic affinity to East Asians. Notably, we identified geography-related genetic substructures: Inner Mongolia Mongolians and Gansu Huis formed a northern branch, Tibetans and Yis from Sichuan constituted a highland branch, and Guangxi Zhuangs exhibited close ties with Hainan Lis and Guangxi Miaos in the southern branch. Additionally, many InDels proved to be ancestry-informative markers for biogeographic ancestry inference. Collectively, these findings underscore the utility of the 114-plex NGS InDel panel as a complementary tool for forensic investigations and as a source of insights into the genetic architecture of ethnolinguistically distinct Chinese populations. [ABSTRACT FROM AUTHOR]

Clinostomum species, a parasitic pathogen of freshwater fish, is widely distributed and infects various host species. Recently, the pathological effect due to Clinostomum metacercarial infection was described in aquaculture in Thailand; however, the global genetic diversity and population structure of this species have not been studied yet. Therefore, this study aimed to provide a detailed description of genetic diversity and population dynamics of the digenean Clinostomum isolated from Trichopodus pectoralis with globally recorded Clinostomum species. The species was characterized molecularly by analyzing 18S rDNA and inter‐transcribed spacer biomarker genes (ITS1 and ITS2). A BLAST search discovered that the 18S rDNA and ITS sequence had a 100% sequence similarity with Clinostomum piscidium isolated from India and Thailand. A comprehensive analysis revealed the presence of 12 distinct haplotypes among the Clinostomum populations. This study suggests that distinct patterns of genetic variation were identified by analyzing molecular variance, pairwise Fst, and employing structure analysis. It was observed that a gradient of genetic variation exists within continents, characterized by higher levels within different groups and lower levels of genetic differentiation. Additionally, a notable presence of mixed haplotypes was observed. The results of neutrality testing suggest that there has been a significant expansion in the populations of Clinostomum in India, America, and Kenya. The discoveries from this study will provide a valuable contribution to comprehending the genetics and evolution of Clinostomum species. Furthermore, key findings will be essential in developing efficient management approaches to prevent and control this parasite. [ABSTRACT FROM AUTHOR]

ABSTRACT The expansion of human settlements over the past few centuries is responsible for an unprecedented number of invasive species introductions globally. An important component of biological invasion management is understanding how introduction history and postintroduction processes have jointly shaped present‐day distributions and patterns of population structure, diversity and adaptation. One example of a successful invader is the European starling (Sturnus vulgaris), which was intentionally introduced to numerous countries in the 19th century, including Aotearoa New Zealand, where it has become firmly established. We used reduced representation sequencing to characterise the genetic population structure of the European starling in New Zealand, comparing it to that present in sampling locations in the native range and invasive Australian range. The population structure and genetic diversity patterns we found suggested restricted gene flow from the majority of New Zealand to the northmost sampling location (Auckland). We also profiled genetic bottlenecks and shared outlier genomic regions, which supported historical accounts of translocations between both Australian subpopulations and New Zealand, and provided evidence of which documented translocation events were more likely to have been successful. Using these results as well as historic demographic patterns, we demonstrate how genomic analysis complements even well‐documented invasion histories to better understand invasion processes, with direct implications for understanding contemporary gene flow and informing invasion management. [ABSTRACT FROM AUTHOR]

Background: Phoebe zhennan, commonly known as "golden-thread nanmu," is one of the most valuable and protected tree species in China. An accurate understanding of the population genetic structure and its environmental factors is of significance for the protection and selection of new P. zhennan varieties. Results: Sixteen nSSR and six cpSSR markers were used to determine the genetic diversity and population structure of P. zhennan and the effect of environmental factors on the genetic structure. The nSSR markers identified a total of 451 number of alleles (Na), while cpSSR markers detected 20 Na. A relative high level of genetic diversity was observed in the P. zhennan population evidenced by high Shannon's information index (I) of 0.671 and 2.294 based on cpSSR and nSSR datasets. The low value of fixation index (F) observed from the nSSR dataset indicated low breeding within the population. The genetic differentiation was mainly detected within populations (only 28% and 13% of the variance being between populations according to the nSSR and cpSSR datasets). Among them, the HNSZX (H = 0.469) and SCSZZ (I = 1.943) populations exhibited the highest level of genetic diversity, while the HNXXT (H = 0.041) and SCLJS (I = 0.943) populations exhibited the lowest level of genetic diversity. The average genetic differentiation coefficient (Fst) and gene flow (Nm) were 0.022–0.128 and 1.698–11.373, respectively, which indicated a moderate level of genetic differentiation and a high level of gene flow. STRUCTURE, neighbor-joining clustering, and principal coordinate analysis divided 543 individuals into two or three categories based on the nSSR or cpSSR datasets. Four temperature, three precipitation, five chemical, five physical, and one soil texture variable showed significant effects on the genetic structure and distribution of P. zhennan populations. Compared to nSSR, the genetic differentiation among populations based on cpSSR datasets conformed to the geographic isolation model, suggesting that geographic and genetic distances should be considered for further genetic conservation and breeding utilization. The importance of in situ conservation units, such as populations with a high level of genetic diversity, more private alleles, and haplotypes (e.g., population SCGTS, SCYFS, and YNYJX), should be emphasized. Additionally, breeding, along with artificially assisted population regeneration and restoration, should also be carefully planned, taking into account climate and soil properties at the same time. Conclusions: In conclusion, this study provided genetic background information for the genetic conservation, management, and utilization of P. zhennan. [ABSTRACT FROM AUTHOR]

This study focuses on the genetic diversity and population structure of Prunus dulcis (almond tree), a crucial agricultural component with widespread cultivation and commercial importance, particularly in Iran, a region with a longstanding tradition of almond cultivation. The diverse almond collection in Iran encompasses many local varieties, breeding selections, rootstocks, and international cultivars. This diversity necessitates advanced genotyping techniques to gain insights into genetic diversity, population structure, and linkage disequilibrium (LD). In this paper, genotyping-by-sequencing (GBS) was employed to analyze 62 almond germplasm samples, identifying approximately 63,537 high-quality single nucleotide polymorphisms (SNPs) distributed across the eight chromosomes of the almond genome. On average, there were 30,225 SNPs per chromosome. The analysis yielded an average polymorphism information content (PIC) of 0.315 and an expected heterozygosity (He) rate of 0.28, indicating a significant level of genetic diversity within the studied almond germplasm. The LD analysis demonstrated a rapid decline, with an average LD decay spanning approximately 300 kb for an r2 value of 0.2. This suggests substantial hybridization among the sampled almond varieties. Principal Component Analysis (PCA) and structure analysis could not differentiate genotypes based on geographical origin, providing further evidence of genetic mixing among the studied almond populations. An Analysis of Molecular Variance (AMOVA) highlighted significant genetic diversity within populations but revealed minimal differences. This comprehensive study of Iran's almond genotypes offers valuable insights for future breeding and conservation efforts, emphasizing this agriculturally significant species abundant genetic diversity and intricate population structure. [ABSTRACT FROM AUTHOR]

Background: Outbreaks of the coral predator Crown-of-Thorns Starfish (CoTS) pose a severe threat to coral reefs in the Indo-Pacific Ocean. In 2018, the South China Sea (SCS) experienced significant CoTS outbreaks, leading to extensive coral mortality across the Xisha, Zhongsha, Dongsha, and Nansha Islands, severely impacting the coral reef ecosystem. Results: To explore the origins of these outbreaks, we conducted a comprehensive genomic analysis using data from genomic single nucleotide polymorphism sites (SNPs) and mitochondrial haplotypes. Our analysis reveals that CoTS populations in the SCS, which exhibit moderate genetic diversity and may have undergone positive selection or population expansion. There was limited genetic differentiation among CoTS populations from XS, ZS, and NS groups. Especially between the XS and ZS groups, there was almost no genetic differentiation. The populations from XS, ZS, and NS groups have strong genetic connections with populations in Vietnam and the Philippines. There was high gene flow from Vietnam to the Xisha Islands and from the Philippines to the Nansha Islands, suggesting that the CoTS populations in these regions primarily originate from these neighboring countries. Conclusion: The comprehensive analyses of SNP and mitochondrial genomes have provided valuable insights into the population genetics of CoTS. This research has generated significant genomic resources and facilitated important studies on the genetics of the CoTS species. By identifying potential source populations and understanding the genetic basis of their spread, managers can develop more effective conservation strategies to protect vulnerable coral reef ecosystems in the SCS. [ABSTRACT FROM AUTHOR]

Simple Summary: This study assessed genetic diversity, runs of homozygosity (ROH), and selection signatures in 11 populations of seven native Japanese chicken breeds and three foreign chicken breeds using 11,493 single nucleotide polymorphisms (SNPs) from restriction-site-associated DNA sequencing. Six Japanese chicken populations showed moderate diversity, with one breed exhibiting higher genetic diversity. Population analyses grouped the 11 populations into four clusters, revealing generally lower ROH values in Japanese populations than in foreign populations. ROH and Fst analyses identified seven SNPs within the selection signatures, five of which were candidate genetic variants for fear-related behavior. Understanding genetic diversity, runs of homozygosity (ROH), and selection signatures is critical for the conservation and breeding management of native Japanese chickens. In this study, genetic diversity, ROH, and selection signatures in 11 populations of seven native Japanese breeds and three foreign breeds with different genetic and behavioral backgrounds were investigated using 11,493 SNPs identified through restriction-site-associated DNA sequencing. The Oh-Shamo (OSM), an aggressive cockfighting breed, exhibited the highest genetic diversity. Six native Japanese breeds, Ingie (IG), Ryujin-Jidori (RYU), Tosa-Jidori (TJI), Tosa-Kukin (TKU), Nagoya (NAG), and Ukkokei (UK), showed intermediate levels of genetic diversity and ROH. Population analyses grouped the 11 populations into four distinct clusters: (1) five populations comprising three foreign breeds (the Fayoumi inbred line, closed-colony G line of White Leghorn, commercial T line of WL, and White Plymouth Rock) and the IG Japanese breed; (2) OSM and two old Jidori breeds (RYU and TJI); (3) TKU and UK; and (4) the meat-type Nagoya breed. ROH and Fst analyses identified seven SNPs on chromosomes 13, 17, 20, 24, and 26, five of which were candidate genetic variants for fear-related behavior. These findings provide insights into genetic diversity and conserved genomic segments valuable for breeding and conservation in Japanese chicken breeds. [ABSTRACT FROM AUTHOR]

Background: Indigenous buffaloes, as the important livestock species contributing to economy of the country, are the lifeline of livelihood in Nepal. They are distributed across diverse geographical regions of the country and have adapted to various feeding, breeding, and management conditions. The larger group of these native buffalo breeds are present in narrow and stiff hilly terrains. Their dispersal indicates a possible environmental adaptation mechanism, which is crucial for the conservation of these breeds. Results: We utilized whole-genome sequencing (WGS) to investigate the genetic diversity, population structure, and selection signatures of Nepalese indigenous buffaloes. We compared 66 whole-genome sequences with 118 publicly available sequences from six river and five swamp buffalo breeds. Genomic diversity parameters indicated genetic variability level in the Nepalese buffaloes comparable to those of Indian breeds, and population genetic structure revealed distinct geography-mediated genetic differentiation among these breeds. We used locus-specific branch length analysis (LSBL) for genome-wide scan, which revealed a list of potentially selected genes in Lime and Parkote breeds that inhabit the hilly region. A gene ontology (GO) analysis discovered that many GO terms were associated with cardiac function regulation. Furthermore, complementary analyses of local selection signatures, tissue expression profiles, and haplotype differences identified candidate genes, including KCNE1, CSF1R, and PDGFRB, related to the regulation of cardiac and pulmonary functions. Conclusions: This study is a comprehensive WGS-based genetic analysis of the native Nepalese buffalo breeds. Our study suggested that the Nepalese "hilly" buffaloes, especially the Lime and Parkote breeds, have undergone some characteristic genetic changes and evolved increased cardiac and pulmonary function for their adaptation to the steep hilly terrains of the country. [ABSTRACT FROM AUTHOR]

Background: Genetic diversity is crucial for conservation efforts as well as breeding programs targeted at the development of improved varieties. Taro, a climate-resilient crop, plays a vital role in the nutritional and economic livelihoods of many households in Nigeria, but its yield is very low due to inadequate genetic improvement efforts. A diversity assessment of Nigerian taro is therefore required to create a premise for its improvement in yield, quality and disease tolerance. In this study, the genetic diversity and population structure of 490 taro cultivars comprising two main gene pools: Dasheen (215) and Eddoe (275), collected from farmers and marketers across seven states in Nigeria was assessed using 3047 Diversity Array Technology single nucleotide polymorphism (DArT-SNP) markers. A subset of 114 taro cultivars, comprising 30 Dasheens and 84 Eddoes were further phenotyped using 24 agro-morphological descriptors. Results: Both phenotypic and molecular characterization revealed higher genetic diversity among the Eddoes than Dasheens. Estimates of gene flow (Nm = 0.353) revealed intermixing of cultivars among the States of collection, with the highest gene flow occurring between cultivars from Anambra and Ondo states and the lowest between Anambra and Kwara states. Population structure and Ward's minimum variance hierarchical cluster based on DArT-SNPs identified four groups, one comprising Dasheen and three comprising Eddoe cultivars. Hierarchical clustering based on phenotypic traits delineated three clusters. Variation between gene pools (49%) was higher than within gene pools (32%). Variation among States of collection was high (41%), while variation among individuals within gene pools (18%) and States of collection (19%) was relatively low. Correlation between phenotypic and genotypic diversity assessments was low (r = 0.01), indicating that both approaches were necessary for assessing genetic diversity in taro. However, genotypic assessment provided better information about genetic diversity of the taro cultivars. Conclusion: This is the first study that represented germplasm collection across the major taro growing regions of Nigeria. The findings from this study based on agro-morphological characterization and DArT-SNP genotyping are critical for genetic characterization, conservation and breeding of taro in Nigeria, mainly initiating hybridization between the two genepools after careful assessment of ploidy levels of the accessions collected in this study. This will facilitate in developing improved taro varieties with desirable traits, such as higher yield, better disease resistance, and improved nutritional quality. [ABSTRACT FROM AUTHOR]

Guar [Cyamopsis tetragonoloba (L.) Taub] was domesticated in India and Pakistan. It is mainly self-pollinated, bushy, and deeply tap-rooted. Guar seed endosperm contains galactomannan gum, which is used in many food products, pharmaceuticals, cosmetics, explosives, meat products, and pet foods, and in the textile industry, yet its genetic diversity remains largely underexplored. Using 7000 high-quality single nucleotide polymorphism (SNP) markers acquired from genotyping by sequencing (GBS), we analyzed the genetic diversity and population structure in 225 guar accessions from India, Pakistan, and the United States. Structure Harvester revealed that K = 3 had the best delta K, whereas K = 2 had the second-highest delta K. Three major genetic clusters (K = 3) were identified using population structure analysis, utilizing an admixture model: 156 accessions (69.3%) were classified into Q1, 23 accessions (10.2%) in Q2, and 16 accessions (7.1%) in Q3. The remaining 30 accessions (13.3%) were included in the admixture. In all three of the subpopulations at K = 3, most of the guar accessions came from India. We also found that these clusters mostly correlated with geographic origins. Results showed that the Q2 and Q3 subpopulations included only guar accessions from India. Genetic resources from Q2 and Q3 may represent an untapped reservoir for introducing beneficial variety into the U.S. breeding populations. This genetic diversity and population structure analysis of the guar gene pool will be of interest to conduct allele mining and donor parent selection for the development of new and better guar germplasm for desired traits. [ABSTRACT FROM AUTHOR]

Subnational divergence in the age and sex structures of populations can have far‐stretching consequences for development: from marriage markets to the potential for violence to economic growth. With urbanization and the demographic transition still underway, rural and urban populations continue to differ across low‐ and middle‐income countries. We examine the extent by which internal migration contributes to these differences, from 1970 to 2014 using estimates of migration between rural and urban sectors based on census data from 45 countries. We found that despite heavily delineated migration profiles by age and sex, internal migration does not alter sex and age structures of rural and urban populations. All the same, internal migration does increase urban growth in Asia and Latin America and the Caribbean. In contrast, in Africa, internal migration has little leverage with the urban transition. Across the continents, there is a potential for de‐urbanization, driven by a rural/urban gap in fertility. As such, the rural population may continue to constitute a significant proportion of national populations, necessitating critical investments to ensure they are not left behind. [ABSTRACT FROM AUTHOR]

Species translocations are increasingly being used in conservation and for biological control. The success of a translocation can be strongly influenced by the evolutionary processes occurring during the early phase of the introduction and the subsequent spread to new regions. In this study, morphological variation and population genetic structure were assessed in the African dung beetle Digitonthophagus gazella, a species that was intentionally introduced to Australia for biological control in 1968 and subsequently spread widely across the northern part of the continent. A dataset based on 1594 neutral single nucleotide polymorphism (SNP) loci that were genotyped in 187 individuals from 12 sites revealed significant genetic divergences between sites (global FST = 0.118) and provides evidence of restricted gene flow among established populations at small to moderate spatial scales (74–500 km). Geometric morphometric analyses revealed significant divergence among populations in the shape of the foretibia, a trait ecologically important for tunnelling in soil and dung. Moreover, phenotypic divergence in this trait for both sexes was significantly higher than genetic differentiation at selectively neutral loci (PST > FST), suggesting that directional selection is contributing to the phenotypic divergences among populations. Our study shows how population structure can establish quickly in an introduced species and highlights the importance of considering local adaptation when performing translocations on established populations. [ABSTRACT FROM AUTHOR]

Information about the population structure, including the age and sex composition, growth characteristics, and diet of fish, is essential for the conservation and sustainable exploitation of fish stock. The burbot, Lota lota, is the only freshwater species of the family Lotidae in the Amur (Heilongjiang) River catchment located in northeastern China. Information on the biological characteristics and data on the population structure of this fish from the Amur River are scarce. To study these factors in burbot, Lota lota, in the Amur River of China, 749 specimens from four sampling areas were taken and analyzed in October 2022, January 2023, and May 2023. The ages of the sampled fish ranged from 1+ to 7+ years. The female/male ratio was 1.04:1, and body length and mass varied from 175 to 595 mm and 73.5 to 1958.7 g, respectively. The length–weight regression parameter b value was estimated as 2.80. The parameters of the von Bertalanffy growth model were L∞ = 596, K = 0.221, and t0 = −0.771 for all sampled fish; L∞ = 625, K = 0.208, and t0 = −0.756 for females; and L∞ = 584, K = 0.219, and t0 = −0.980 for males. The analysis of the stomach contents showed fish to be the major source of nutrition across all areas and sampling periods. In January, the secondary prey of burbots in the Huma reach of the upper Amur River was aquatic insect larvae, while, in the Tongjiang and Fuyuan reaches of the middle Amur River, the secondary prey was shrimp. The mean stomach fullness index and rate of empty stomachs differed with the sampling area, with the greatest proportion of empty stomachs observed in the Luobei reach of the middle Amur River, and the lowest in the Tongjiang and Fuyuan reaches. The mean stomach fullness index showed the opposite trend. In the Huma reach, the contributions of fish to the diet and the mean stomach fullness index were significantly higher in May than in October and January. The study provides the first detailed information on the population age and sex structure, growth patterns, and feeding ecology of burbots from the Amur River, China. The results will aid in formulating management strategies and regulations for local populations of burbots in the Amur River, China. [ABSTRACT FROM AUTHOR]

Frogeye leaf spot on soybeans is traditionally considered as a southern disease in the United States but its impact in North Central USA has been rising in recent years. In this study, we investigated the population structure and mating type distribution in the C. sojina population from Indiana, USA. Based on 27 single nucleotide polymorphism markers, 49 multi-locus genotypes (MLGs) were identified in 234 isolates collected from 29 counties in Indiana in 2020. Bayesian analysis grouped the 49 MLGs into three clusters. This grouping was supported by principal coordinate analysis and, in large part, by the unweighted pair group method with arithmetic mean and minimal spanning tree. Only one mating-type idiomorph was found in each isolate and in each MLG. The MAT1-1 idiomorph was found in 22 MLGs and the MAT1-2 idiomorph was found in 27 MLGs. Based on clone-corrected data, the distribution of mating-type idiomorphs did not deviate significantly from 1:1 ratio in Indiana as a whole and in 22 out of 24 counties where two or more MLGs were found. Thirty MLGs contained QoI-resistant isolates and 22 MLGs contained QoI-sensitive isolates, with three MLGs containing both types of isolates. MLG1, the most common MLG with 90 isolates, contained mostly QoI-resistant isolates. Interestingly, MLG1 was also the dominant genotype in the Tennessee population collected in 2015, suggesting that MLG1 has been a dominant genotype in a wider region for many years. Based on the standard index of association ( r ¯ d), the Indiana population as a whole was in significant linkage disequilibrium. However, in five out of 16 counties where three or more MLGs were found, the null hypothesis of linkage equilibrium was not rejected. Tests of linkage disequilibrium between locus pairs showed that 33.3% of locus pairs on the same contigs were in significant disequilibrium and 17.7% of locus pairs on different contigs were in significant disequilibrium. The possibility of a cryptic sexual stage was discussed. [ABSTRACT FROM AUTHOR]

Magnaporthe oryzae, a filamentous heterothallic ascomycete fungus that serves as the causative agent of rice blast disease, is globally distributed in rice-growing regions. Populations shaped by environmental factors and human intervention play important roles in the formation of genetic structure. In this study, population structures and spatiotemporal dynamics were investigated based on large-scale whole genomic sequences of rice-infecting M. oryzae around the world. By analyzing these genetic structures, we identified divergent clades that crossed geographic boundaries. While we observed associations between the isolates and their geographic origins, we also found that there were frequent migration events occurring across Asia in main rice cultivation regions. Within Asia, China was the migration origin, facilitating gene flows to Japan and South Korea. Since the 1970s, the genetic diversity of M. oryzae populations in China has also shown a steadily increasing trend, continuing through to the 2020s. Additionally, our analysis of the evolutionary history of Asian M. oryzae populations provided insights into the population expansion that has taken place in recent decades. Overall, our findings indicate that human-mediated gene flows played a pivotal role in shaping the genetic structure of M. oryzae. [ABSTRACT FROM AUTHOR]

(1) Background: Buffaloes are crucial livestock species for food and service in tropical and subtropical regions. Buffalo genetics, particularly in indigenous Chinese breeds such as the Xiangxi white buffalo (XWB), remains an intriguing area of study due to its unique traits and regional significance. (2) Methods: This investigation utilized the whole-genome sequences of twenty XWBs (newly sequenced), along with eighty published whole-genome sequences of other buffalo breeds (including Guizhou white buffalo, river buffalo, and Chinese buffalo in the Yangtze River). Using whole-genome sequencing analysis technology, the population structure, genomic diversity, and selection signatures of XWB were determined. (3) Results: This study revealed that the XWB, being phylogenetically positioned in the middle and lower reaches of the Yangtze River, exhibited substantial genomic diversity. Employing four selection sweep detection methods (CLR, iHS, π-ratio, and FST), several genes were positively identified for adaptive traits in the XWB, including coat color phenotypes (ASIP, KIT), the nervous system (GRIK2), reproduction (KCNIP4), growth and development (IFNAR1, BMP6, HDAC9, MGAT4C, and SLC30A9), the body (LINGO2, LYN, and FLI1), immunity (IRAK3 and MZB1), and lactation (TP63, LPIN1, SAE1). (4) Conclusions: In conclusion, this study enhances our understanding of the genetic distinctiveness and adaptive traits of XWB, highlighting selection signatures crucial for future breeding and conservation and ensuring sustainable use of this vital livestock resource. [ABSTRACT FROM AUTHOR]

Background/Objectives: The swimming crab Charybdis feriata is an important commercial fishery species and a major economic contributor to the southeast coastal fishing communities in China. Under the scenario of resource decline and shortage in the market over recent years, it has become more urgent and necessary to explore the fine-scale population genetic characteristics of C. feriata. Methods: In this study, the genotyping-by-sequencing (GBS) method was used to estimate the genome-wide genetic variation in and population differentiation pattern of C. feriata collected from four geographical locations (Zhoushan, Quanzhou, Yangjiang, and Qinzhou) along the southeast coast of China. Results: A total of 18,815 high-quality single-nucleotide polymorphisms (SNPs) were identified and the results revealed the existence of high genetic diversity and low genetic divergence among the populations of C. feriata. Floating eggs and larvae transported by alongshore currents during the reproductive season might enhance the interpopulation genetic exchange. Principal component analysis (PCA) and a phylogenetic tree showed a high genetic connectivity of C. feriata across the southeast coast of China, but C. feriata distributed in the Zhoushan Archipelago might possess some genetic distinctiveness and diversification. Conclusions: The results supplemented basic genetic information of C. feriata at the genome level and also provided specific knowledge that could lead to the improved spatial management of fishery resources. [ABSTRACT FROM AUTHOR]

Background: X-chromosomal short tandem repeats (X-STRs) are crucial in forensic applications, particularly in complex kinship cases, and play an important role in population genetics. However, there is limited data on X-STR variation in Pakistani populations, especially among ethnic groups like Kashmiri and Punjabi. Methodology: This study investigates the forensic and genetic properties of 12 X-STRs from the Investigator Argus X-12 Kit (QIAGEN, Hilden, Germany) in 125 families (75 Kashmiri, 50 Punjabi) from Azad Jammu and Kashmir and Punjab, Pakistan. Results: In both populations, a total of 222 alleles were identified across the 12 X-STR loci (Punjabi 171 alleles, Kashmiri 161 alleles), with allele frequencies ranging from 0.0056 to 0.3033. DXS10148 was the most polymorphic locus with 28 alleles, while DXS7132 was the least polymorphic with 9 alleles. Most loci were in linkage equilibrium, except for the DXS10135/DXS10148 pair in males, with no loci exhibiting significant linkage disequilibrium in females. The combined power of discrimination was 0.999 999 9977 for Kashmiri males, 0.999 999 999 999 9746 for Kashmiri females, and 0.999 999 999 999 9781 for Punjabi females. In Kashmiri males, 34, 31, 28, and 32 haplotypes were observed across the four linkage groups (LG1, LG2, LG3, and LG4), though these groups did not form stable haplotypes, as indicated by Linkage Equilibrium within and significant Linkage Disequilibrium between groups. Conclusions: Genetic structure analysis using Principal Component Analysis and STRUCTURE revealed distinct clustering patterns for the Kashmiri and Punjabi populations, indicating unique genetic backgrounds and ancestry influences, particularly distinguishing them from East Asian populations. This study provides a comprehensive analysis of X-STR variation in Punjabi and Kashmiri populations, offering valuable insights for forensic and population genetic studies. [ABSTRACT FROM AUTHOR]

Background/Objectives: Orenburg goats are renowned for their soft down that acts as a substrate for warm clothing, particularly shawls that have an international reputation. As with many local livestock breeds, however, the Orenburg is presently at risk of extinction, an issue that can be addressed by assessing population genetic diversity and, thereafter, encouraging as much outbreeding as possible. Using single-nucleotide polymorphism (SNP)-based data, therefore, we analyzed the genetic diversity and population structure of modern Orenburg goats using samples collected from an expedition to Orenburg Oblast in 2024. Methods: We applied the Goat SNP50 BeadChip (Illumina, San Diego, CA, USA) for the genotyping of Orenburg goats from modern and archived populations. SNP genotypes of three Orenburg populations sampled in 2017 and 2019, Altai Mountain, Altai White, and Soviet Mohair breeds, were added to the dataset. Results: Principal component analysis and network and admixture analyses demonstrated that the genetic background inherent to the archived group of Orenburg goats was maintained in all modern populations. Values of genetic diversity indicators in modern populations were compatible with those obtained in comparison groups. Runs of homozygosity (ROH) were found in all the Orenburg goat populations (with a mean ROH length of 72.6–108.9 Mb and mean ROH number of 28–36). Genomic inbreeding based on ROH was low in all the Orenburg populations (FROH = 0.03–0.045). Conclusions: We showed that the ancestral background is retained in present-day Orenburg goats sampled in 2024. We provide the genetic basis through which certain breeder animals may be selected and bred traditionally or ex situ through a conservation program of gamete preservation. [ABSTRACT FROM AUTHOR]

The results of a comparative study of the genetic structure, parameters of intraspecific genetic diversity, and spatial differentiation of 35 populations of Picea abies–P. obovata–P. koraiensis species complex, located within the areas of distribution of "pure" species and in the contact zones of their ranges were presented. P. abies populations from Eastern Europe (Belarus, Poland); spruce populations from the European part of Russia, the Urals, and the West Siberian Plain, located in the zone of P. abies and P. obovata introgressive hybridization; P. obovata populations from various parts of the extensive range of this species in Siberia and Mongolia; and P. koraiensis populations from the Russian Far East and Northeast China were analyzed. The study of genetic variability and differentiation of populations was based on the analysis of variability of three microsatellite loci: Pt63718, Pt71936, and Pt26081, developed on the basis of Pinusthunbergii Parl chloroplast genome. The use of these DNA markers made it possible to obtain data indicating a fairly high degree of P. koraiensis genetic divergence from two other spruce species included in the complex, P. abies and P. obovata. Korean spruce growing in the Far East differs significantly from the populations of these species in the number and composition of haplotypes, the level of genetic diversity, and population structure, which gives us reason to consider it as a separate species. [ABSTRACT FROM AUTHOR]

Potential immortality is observed in several species (e.g. prickly pear cactus, hydra and flatworms) and is indicative of their negligible or even negative senescence rates. Unlike in senescent species, which experience reduced individual performance with age due to physiological degradation, species with negligible or negative senescence display mortality rates that remain constant or decline with age, respectively. These rates vary across taxa and are correlated with life history traits. Yet, the extent to which variable resource availability, a key driver of variation in life history traits, impacts species that show negligible or negative senescence is currently unknown.Here, we examine whether and how variation in the quantity, quality and feeding interval of resources impact population structure, population performance and life history trait trade‐offs in two long‐lived planaria that do not senesce: Schmidtea mediterranea and Dugesia tahitiensis. In a full factorial design, different combinations of resource quantity (reduced intake, standard intake and high intake) and quality (high and low quality) were provided in two different feeding intervals (7‐day and 14‐day intervals) for 19 weeks.We show that variability in resource availability, via decreases in quantity, quality and frequency of resources, does not diminish population viability in either species but does result in suboptimal conditions of stress in S. mediterranea.The high population viability we report can be attributed to two different mechanisms: increased reproduction or increased investment into maintenance at the expense of reproduction. Moreover, which mechanism was responsible for said high population viability was context‐dependent and modulated by the specific life history strategy of the two planaria species.We show that suboptimal conditions can cause stress responses that have significant impacts on non‐senescent species. The context‐dependent response we observe suggests that species that do not senesce but are subject to suboptimal conditions of stress may ultimately exhibit declines in performance and ultimately die. A clearer understanding of the impact of suboptimal conditions of resource availability on non‐senescent species is needed to determine the extent of stress experienced and ultimately whether a species can truly be immortal. [ABSTRACT FROM AUTHOR]

Pterocarpus santalinus L.f. is an endangered tree species that is cherished worldwide for its valuable deep red-colored heartwood, which has multiple uses. This species exhibits a wide range of medicinal properties and offers immense potential for the discovery of bioactive compounds of pharmacological importance. The overharvesting of this species for heartwood has led to a gradual decline in its natural populations, thereby depleting its genetic resources and contributing to the loss of genetic diversity. Therefore, it is essential to assess genetic diversity, as such information allows for the effective conservation and utilization of genetic resources. In the present study, the genetic diversity and population structure among 40 germplasm accessions originating from 8 populations of P. santalinus were analyzed using six cross-species simple sequence repeats (SSR), 20 each of inter simple sequence repeats (ISSR) and random amplified polymorphic DNA (RAPD) markers. SSR markers revealed higher polymorphism (100 %), followed by ISSRs (82.81 %) and RAPDs (67.50 %), across all the accessions. The mean values of the polymorphic information content (PIC), effective multiplex ratio (EMR), and marker index (MI) were higher for SSRs (0.84, 9.17, and 7.7), followed by ISSRs (0.262, 4.474, and 1.251) and RAPDs (0.204, 3.268 and 0.970, respectively), indicating the superiority of SSRs in detecting polymorphisms in red sanders. Similarly, the estimates of Nei's gene diversity (H) and Shannon's information index (I) varied across the studied accessions, with the highest values for SSRs (H = 0.528, I = 0.923), followed by ISSRs (H = 0.287, I = 0.428) and RAPDs (H = 0.206, I = 0.307). However, the genetic statistic (Gst) or fixation statistic (Fst) and gene flow (Nm) values were higher for RAPDs (0.455 and 0.598) and ISSRs (0.446 and 0.620) than for SSRs (0.383 and 0.489, respectively), indicating significant genetic differentiation of the populations and moderate gene flow among the populations. Analysis of molecular variance (AMOVA) with SSR, ISSR, and RAPD markers revealed that a greater proportion of genetic variation resided within populations (74 %, 69 %, and 66 %, respectively) than among populations (26 %, 31 %, and 34 %, respectively). Hierarchical clustering on the basis of RAPDs grouped most of the accessions according to the population of origin; however, this clustering was different for the ISSR and SSR markers. STRUCTURE analysis divided the accessions into four, two, and three groups with SSR, ISSR, and RAPD markers, respectively, with admixtures detected in all the groups pointing toward shared genetic lineages and diverse genetic ancestry among the accessions of different populations. Overall, the populations of Gumudipoondi of Tamil Nadu and K.V. Bhavi of Andhra Pradesh were genetically more diverse than other populations, as revealed by genetic diversity estimates obtained with SSR and ISSR marker systems; therefore, the accessions of these populations must be prioritized for conservation and utilization in breeding programs for genetic improvement. [Display omitted] • Genetic diversity was assessed among 40 accessions of P. santalinus using 6 cross-species SSR, 20 each of ISSR and RAPD primers. • Cross-species SSRs were more efficient in detecting genetic diversity in the studied populations than ISSRs and RAPDs. • The populations of Gumidipoondi of Tamil Nadu (GTN) and K.V. Bhavi of Andhra Pradesh (KAP) exhibited higher genetic diversity than other populations according to SSR and ISSR marker analysis. • Analysis of molecular variance with SSR, ISSR and RAPD markers showed that genetic variations within populations (74 %, 69 % and 66 %) were greater than among populations (26 %, 31 % and 34 %). • STRUCTURE analysis using SSR, ISSR and RAPD markers divided the populations into four, two and three genetic groups, respectively, with admixtures detected in all genetic groups. [ABSTRACT FROM AUTHOR]

In order to describe large-scale spatial structure of sockeye salmon on the Asian part of the range, the variability of 45 SNP loci was analyzed in 22 samples from the Northwest coast of the Pacific Ocean. Three large regional population complexes were identified: Southwest Kamchatka, Kamchatka River basin, and the Northeast (comprising stocks from Koryak Highlands). Populations within the identified complexes are connected by gene migration and have a common origin, close geographic proximity, comparable climatic, landscape, and environmental conditions in the freshwater and early marine periods of sockeye salmon life. Populations confined to watersheds of the North coast of the Sea of Okhotsk (Palana and Okhota rivers), along with island populations, displayed distinctions from the isolated population complexes. It is hypothesized that the marked divergence observed in island populations is primarily caused by genetic drift occurring during long periods of isolation. The pronounced divergence of Palana River population may be the result of both genetic drift and natural selection, driven by the challenging smoltification and specific conditions of freshwater period in this watershed. At the same time in the Okhota River population, demographic factors such as genetic drift and bottlenecks played a key role. [ABSTRACT FROM AUTHOR]

Colombian Creole pigs have adapted to tropical conditions for over 500 years. They have been modified by natural and artificial selection in different regions. At present, the diversity and current introgression status are unknown. The objective was to estimate the genomic diversity, linkage disequilibrium, population structure, and admixture of four Colombian pig breeds and their relationship with other breeds worldwide. Three Colombian pig breeds (SPE-San Pedreño, 11 samples; ZUN-Zungo, 11 samples; CM-Casco de Mula, ten samples) from the conservation nucleus and one biotype not recognized as a breed (CCH-Criollo Chocoano, seven samples) were genotyped using the Illumina GGP-Porcine80K chip. Open-access data from seven international breeds were also included. Colombian Creole pigs showed moderate genetic differentiation (FST 0.14) globally, but several groups of animals separated, suggesting local clustering due to geographical isolation or different founding effects. Colombian Creole pigs showed breed imprinting and specific grouping in all analyses except for CCH, which, like the Ecuadorian Creole, was a cluster of admixtures. The Colombian Creole pigs revealed a significant relationship with the Iberian pig and some other breeds to varying degrees. However, good maintenance of the conservation nucleus was evidenced. Potential adaptive genes, mainly related to immunological functions, were found, according to FST and pcadapt analyses. This study provides a foundation and scientific data for policy decisions on zoogenetic resources. [ABSTRACT FROM AUTHOR]

Lumpy skin disease (LSD) is a transboundary, viral disease of cattle with a significant economic impact on the livestock industry. This study describes the epidemiological investigations of outbreaks of LSD that occurred in 2022 in three Indian states viz., Haryana, Himachal Pradesh and Rajasthan and the genetic characterization of Lumpy skin disease viruses (LSDVs). Also, the population structure analysis of LSDVs was carried out. Out of 138 scab samples tested from suspected cattle for LSDV, 106 were found positive. Of these, nine representative scab samples were further genetically characterized. Phylogenetic analysis based on the P32 and EEV gene sequences depicted that the LSDV strains of the present study had nucleotide identity of 100% and 99.10–99.45%, respectively with the LSDV/2019 field strains of India. Multiple sequence alignment of the EEV glycoprotein gene sequences revealed nucleotide polymorphisms at three positions viz., G178A, G253A and A459G in circulating LSDV/2022 field strains. Based on the median joining network analysis of the EEV gene, 12 haplotypes were identified among the LSDV populations. Population structure analysis corresponding to the EEV gene revealed high haplotype (0.8486 ± 0.026) and low nucleotide diversities (0.00636 ± 0.0006) and negative values for neutrality indices, indicating a high number of closely related haplotypes and the studied population may have undergone a recent expansion. The findings will help in understanding the distribution and dynamics of LSDV populations, which will prove pivotal in designing and implementing effective management and control strategies. [ABSTRACT FROM AUTHOR]

In crop breeding, genomic selection (GS) serves as a powerful tool for predicting unknown phenotypes by using genome-wide markers, aimed at enhancing genetic gain for quantitative traits. However, in practical applications of GS, predictions are not always made within populations or for individuals that are genetically similar to the training population. Therefore, exploring possibilities and effective strategies for across-population prediction becomes an attractive avenue for applying GS technology in breeding practices. In this study, we used an existing maize population of 5820 hybrids as the training population to predict another population of 523 maize hybrids using the GBLUP and BayesB models. We evaluated the impact of optimizing the training population based on the genetic relationship between the training and breeding populations on the accuracy of across-population predictions. The results showed that the prediction accuracy improved to some extent with varying training population sizes. However, the optimal size of the training population differed for various traits. Additionally, we proposed a population structure-based across-population genomic prediction (PSAPGP) strategy, which integrates population structure as a fixed effect in the GS models. Principal component analysis, clustering, and Q-matrix analysis were used to assess the population structure. Notably, when the Q-matrix was used, the across-population prediction exhibited the best performance, with improvements ranging from 8 to 11% for ear weight, ear grain weight and plant height. This is a promising strategy for reducing phenotyping costs and enhancing maize hybrid breeding efficiency. [ABSTRACT FROM AUTHOR]

Alnus glutinosa plays a crucial role in flood control, riverbank stabilization, and water purification. Recognized for its ecological significance, it is listed in the Red Book of Kazakhstan. This study investigated the genetic variability of A. glutinosa populations in Kazakhstan, analyzing 78 trees from seven populations in the Bayanaul mountain forest massif and the northern Turgay regions using 12 SSR markers. The study identified an average of 6.3 alleles and 2.783 effective alleles, as well as observed and expected heterozygosities of 0.570 and 0.562, respectively, reflecting genetic diversity. Among the populations, KS1 (northern Turgay) and PVL3 (Bayanaul) displayed the highest diversity, while PVL5 (Bayanaul) showed slightly lower diversity. The analysis of molecular variance results indicated that 86% of the genetic diversity occurred within populations, with 14% attributed to differences between populations. A UPGMA tree based on Nei's genetic distance revealed three distinct clusters, suggesting geographically structured genetic variability in A. glutinosa populations. [ABSTRACT FROM AUTHOR]

Sugar beet (Beta vulgaris L.) is a biennial herb belonging to the Amaranthaceae family. It contributes to approximately 30% of the world's total sucrose production and is an economically important crop. In this study, we analyzed the genetic diversity and population structure of 132 exotic sugar beet varieties using three molecular makers: four pairs of simple sequence repeat (SSR) primers, three pairs of insertion–deletion sequence (InDel) primers, and 20 cis-element amplification polymorphism (CEAP) primers. The results indicated that the number of alleles (Na) was 298, among which the number of effective alleles (Ne) was 182.426 (accounting for approximately 61.2%). The mean value of the genetic diversity index was 0.836. The polymorphic information content (PIC) was 0.639–0.907 (mean = 0.819), indicating a high level of polymorphism. These sugar beet varieties were classified into six clusters using the UPGMA method of cluster analysis. Population structure analysis revealed that the most ideal K value was 6. This indicated that the test materials could be divided into six categories, consistent with the clustering results. The clustering results indicated that most sugar beet varieties from the same breeding company clustered together, and the genetic distance between them was small, indicating that they may share the same male and/or female parent. Some varieties from different companies clustered together, indicating a narrow genetic base and potential exchange of germplasm resources between breeding companies. This study revealed the genetic differences among exotic sugar beet varieties and characteristics of the population structure. It provided a scientific basis for the identification of sugar beet varieties and markers-assisted breeding in China in the future. [ABSTRACT FROM AUTHOR]

ABSTRACT Isolation by distance and biogeographical boundaries define patterns of population genetic structure for harbour porpoise along the Pacific coast from California to British Columbia. Until recently, inadequate sample sizes in many regions constrained efforts to characterise population genetic structure throughout the coastal waters of Alaska. Here, tissue samples from beachcast strandings and fisheries bycatch were supplemented with targeted environmental DNA (eDNA) samples in key regions of Alaska coastal and inland waters. Using a geographically explicit, hierarchical approach, we examined the genetic structure of Alaska harbour porpoises, using both mitochondrial DNA (mtDNA) sequence data and multilocus SNP genotypes. Despite a lack of evidence of genetic differentiation from nuclear SNP loci, patterns of relatedness and genetic differentiation from mtDNA suggest natal philopatry at multiple geographic scales, with limited gene flow among sites possibly mediated by male dispersal. A priori clustering of sampled areas at an intermediate scale (eastern and western Bering Sea, Gulf of Alaska and Southeast Alaska) best explained the genetic variance (12.37%) among regions. In addition, mtDNA differentiation between the Gulf of Alaska and eastern Bering Sea, and among regions within the Gulf of Alaska, indicated significant genetic structuring of harbour porpoise populations in Southeast Alaska. The targeted collection of eDNA samples from strata within Southeast Alaska was key for elevating the statistical power of our mtDNA dataset, and findings indicate limited dispersal between neighbouring strata within coastal and inland waters. These results provide evidence supporting a population boundary within the currently recognised Southeast Alaska Stock. Together, these findings will prove useful for ongoing management efforts to reduce fisheries conflict and conserve genetic diversity in this iconic coastal species. [ABSTRACT FROM AUTHOR]