Studies Of Population Structure Research Articles

Complete Mitochondrial Genome of the Eggplant Fruit and Shoot Borer, Leucinodes orbonalis Guenée (Lepidoptera: Crambidae), and Comparison with Other Pyraloid Moths.

The eggplant fruit and shoot borer (EFSB) (Leucinodes orbonalis Guenée) is a devastating lepidopteran pest of eggplant (Solanum melongena L.) in the Philippines. Management of an insect pest like the EFSB requires an understanding of its biology, evolution, and adaptations. Genomic resources provide a starting point for understanding EFSB biology, as the resources can be used for phylogenetics and population structure studies. To date, genomic resources are scarce for EFSB; thus, this study generated its complete mitochondrial genome (mitogenome). The circular mitogenome is 15,244 bp-long. It contains 37 genes, namely 13 protein-coding, 22 tRNA, and 2 rRNA genes, and has conserved noncoding regions, motifs, and gene syntenies characteristic of lepidopteran mitogenomes. Some protein-coding genes start and end with non-canonical codons. The tRNA genes exhibit a conserved cloverleaf structure, with the exception in trnS1. Partitioned phylogenetic analysis using 72 pyraloids generated highly supported maximum likelihood and Bayesian inference trees revealing expected basal splits between Crambidae and Pyralidae, and Spilomelinae and Pyraustinae. Spilomelinae was recovered to be paraphyletic, with the EFSB robustly placed before the split of Spilomelinae and Pyraustinae. Overall, the EFSB mitogenome resource will be useful for delineations within Spilomelinae and population structure analysis.

A Cryptic Subterranean Mammal Species, the Lesser Blind Mole Rat (Nannospalax leucodon syrmiensis)-Retreated but Not Extinct.

Blind mole rats (genus Nannospalax) attract a great deal of attention because of their cancer resistance and longevity. Due to the high rate of chromosome rearrangements, 74 Nannospalax chromosomal forms have been discovered. The convergence of their external morphology complicates their taxonomy, and many cryptic species remain unrecognized. Thus, the European N. leucodon supersp. is listed in the IUCN Red List of Threatened Species with "Data Deficient" status. It is crucial for the conservation of biodiversity to clarify its taxonomy, to recognize each cryptic species, and assign to them the correct conservation status. Of the more than 20 chromosomal forms described within N. leucodon, five cryptic species occur in Serbia. The most threatened among them-N. l. syrmiensis, described and named 50 years ago in the regions of Srem, Belgrade and Mačva-has been declared extinct in the literature, which may have negative consequences for the conservation of wildlife genetic diversity. Through five years of fieldwork and comparison of 16SrRNA and MT-CYTB gene segments between old, archived teeth and recently collected material, we show that N. l. syrmiensis is not extinct. However, its habitat has been fragmented and reduced, owing primarily to anthropogenic impact. Therefore, detailed surveillance, population-structure studies, risk assessment, and appropriate conservation measures are needed.

Identification of pleiotropic loci mediating structural and non-structural carbohydrate accumulation within the sorghum bioenergy association panel using high-throughput markers.

Molecular characterization of diverse germplasm can contribute to breeding programs by increasing genetic gain for sorghum [Sorghum bicolor (L.) Moench] improvement. Identifying novel marker-trait associations and candidate genes enriches the existing genomic resources and can improve bioenergy-related traits using genomic-assisted breeding. In the current scenario, identifying the genetic loci underlying biomass and carbon partitioning is vital for ongoing efforts to maximize each carbon sink's yield for bioenergy production. Here, we have processed a high-density genomic marker (22 466 550) data based on whole-genome sequencing (WGS) using a set of 365 accessions from the bioenergy association panel (BAP), which includes ~19.7 million (19 744 726) single nucleotide polymorphism (SNPs) and 2.7 million (~2 721 824) insertion deletions (indels). A set of high-quality filtered SNP (~5.48 million) derived markers facilitated the assessment of population structure, genetic diversity, and genome-wide association studies (GWAS) for various traits related to biomass and its composition using the BAP. The phenotypic traits for GWAS included seed color (SC), plant height (PH), days to harvest (DTH), fresh weight (FW), dry weight (DW), brix content % (BRX), neutral detergent fiber (NDF), acid detergent fiber (ADF), non-fibrous carbohydrate (NFC), and lignin content. Several novel loci and candidate genes were identified for bioenergy-related traits, and some well-characterized genes for plant height (Dw1 and Dw2) and the YELLOW SEED1 locus (Y1) were validated. We further performed a multi-variate adaptive shrinkage analysis to identify pleiotropic QTL, which resulted in several shared marker-trait associations among bioenergy and compositional traits. Significant marker-trait associations with pleiotropic effects can be used to develop molecular markers for trait improvement using a marker-assisted breeding approach. Significant nucleotide diversity and heterozygosity were observed between photoperiod-sensitive and insensitive individuals of the panel. This diverse bioenergy panel with genomic resources will provide an excellent opportunity for further genetic studies, including selecting parental lines for superior hybrid development to improve biomass-related traits in sorghum.

Comparative Analysis of Chloroplast Pan-Genomes and Transcriptomics Reveals Cold Adaptation in Medicago sativa.

Alfalfa (Medicago sativa) is a perennial forage legume that is widely distributed all over the world; therefore, it has an extremely complex genetic background. Though population structure and phylogenetic studies have been conducted on a large group of alfalfa nuclear genomes, information about the chloroplast genomes is still lacking. Chloroplast genomes are generally considered to be conservative and play an important role in population diversity analysis and species adaptation in plants. Here, 231 complete alfalfa chloroplast genomes were successfully assembled from 359 alfalfa resequencing data, on the basis of which the alfalfa chloroplast pan-genome was constructed. We investigated the genetic variations of the alfalfa chloroplast genome through comparative genomic, genetic diversity, phylogenetic, population genetic structure, and haplotype analysis. Meanwhile, the expression of alfalfa chloroplast genes under cold stress was explored through transcriptome analysis. As a result, chloroplast genomes of 231 alfalfa lack an IR region, and the size of the chloroplast genome ranges from 125,192 bp to 126,105 bp. Using population structure, haplotypes, and construction of a phylogenetic tree, it was found that alfalfa populations could be divided into four groups, and multiple highly variable regions were found in the alfalfa chloroplast genome. Transcriptome analysis showed that tRNA genes were significantly up-regulated in the cold-sensitive varieties, while rps7, rpl32, and ndhB were down-regulated, and the editing efficiency of ycf1, ycf2, and ndhF was decreased in the cold-tolerant varieties, which may be due to the fact that chloroplasts store nutrients through photosynthesis to resist cold. The huge number of genetic variants in this study provide powerful resources for molecular markers.

Genomic resources for the Yellowfin tuna Thunnus albacares.

The Yellowfin tuna (Thunnus albacares) is a large tuna exploited by major fisheries in tropical and subtropical waters of all oceans except the Mediterranean Sea. Genomic studies of population structure, adaptive variation or of the genetic basis of phenotypic traits are needed to inform fisheries management but are currently limited by the lack of a reference genome for this species. Here we report a draft genome assembly and a linkage map for use in genomic studies of T. albacares. Illumina and PacBio SMRT sequencing were used in combination to generate a hybrid assembly that comprises 743,073,847 base pairs contained in 2,661 scaffolds. The assembly has a N50 of 351,587 and complete and partial BUSCO scores of 86.47% and 3.63%, respectively.Double-digest restriction associated DNA (ddRAD) was used to genotype the 2 parents and 164 of their F1 offspring resulting from a controlled breeding cross, retaining 19,469 biallelic single nucleotide polymorphism (SNP) loci. The SNP loci were used to construct a linkage map that features 24 linkage groups that represent the 24 chromosomes of yellowfin tuna. The male and female maps span 1,243.8cM and 1,222.9cM, respectively. The map was used to anchor the assembly in 24 super-scaffolds that contain 79% of the yellowfin tuna genome. Gene prediction identified 46,992 putative genes 20,203 of which could be annotated via gene ontology. The draft reference will be valuable to interpret studies of genome wide variation in T. albacares and other Scombroid species.

Click-click, who’s there? Acoustically derived estimates of sperm whale size distribution off western Ireland

Understanding the structure of populations is a critical element to the establishment of management and conservation measures. Sperm whales Physeter macrocephalus are characterised by a demographic spatial segregation, associated with a conspicuous sexual dimorphism reflected in their vocalisations. These characteristics make acoustic techniques very relevant to the study of sperm whale population structure, especially in remote, challenging environments. The reliability of using inter-pulse intervals of sperm whale clicks to infer body size has long been verified and extensively used. We provide the first size structure estimates of the sperm whale population in an area where assumptions on population structure mainly relied on sparse observations at sea, whaling records and stranding data. Over 10,000 hours of acoustic data collected using both static acoustic recorders and towed hydrophone arrays in Irish offshore waters were processed using a machine learning-based tool aimed at automatically extracting inter-pulse intervals from sperm whale recordings. Our analyses suggested that, unlike previously thought, large males would not account for the majority of the animals recorded in the area. We showed that adult females/juvenile males (length 9-12 m) were predominant, accounting for 49% (n = 788) of the number of individuals recorded (n = 1,595), while the proportions of immature individuals (length<9 m) and adult males (length >12 m) were well balanced, accounting for 25% (n = 394) and 26% (n = 413) of the recorded whales, respectively. Our data also suggested some size segregation may be occurring within the area, with smaller individuals to the south. The implications of such findings are crucial to the management of the population and provide an important baseline to monitor changes in population structure, particularly relevant under changing habitat conditions.

Study of Molecular Biodiversity and Population Structure of Vitis vinifera L. ssp. vinifera on the Volcanic Island of El Hierro (Canary Islands, Spain) by Using Microsatellite Markers

El Hierro island is postulated as the most biodiverse of the archipelago. To verify this hypothesis, the 87 individuals collected throughout the island were genotyped with 20 SSRs. As a result of this study, 28 varieties were described, 6 of which were new (Uval piñero, Uvalero volcánico, Pinar negro, Seis de Carlos, Tesoro blanco, Uval negro), and the first rose sport of the local Canary Islands variety Bermejuela was also found. Fifteen errors were detected in total. Eleven varieties were identified that were unknown to the vine growers and twenty individuals with variations (mutations) were found, of which two had already been described in a previous prospection in Lanzarote Island (intra-varietal variability). From this study, it is also proposed to incorporate 33 new names into the world database, corresponding mostly to the individuals and variations described for the first time, which represents a lexicographic enrichment. Finally, the singularity of the population of vines adapted to El Hierro island is demonstrated, not only with respect to the population of Canary Islands vines, but also with respect to the world population. The biodiversity and uniqueness of El Hierro and the Canary Archipelago reaffirm the proposal that the Canary Islands should be considered a world biodiversity centre.

Genetic diversity and population structure analysis in early generations maize inbreds derived from local germplasm of Eastern Himalayan regions using microsatellite markers

Abstract The North-Eastern region (NER) of India falls under the Eastern Himalayan region and it is a bio-diversity hub. Diverse maize landraces with wide adaptability to extreme climatic and soil scenario like heavy rainfall, drought and acidic soil conditions have been grown in NER since time immemorial. However, maize diversity in NER region has drastically reduced due to introduction of high yielding varieties and hybrids. Modern maize breeding programmes are focused on high yield but other unique traits like stay green trait, prolificacy (more than one fertile ear per plant), self-fertilizing ability are also important and the local germplasm of the NER region can contribute with these unique traits. Prior to the selection of any lines in several breeding programmes, assessment of genetic diversity and population structure are basic requirements. Hence, in the present study assessment of genetic diversity and population structure study in 30 maize inbreds developed from different germplasm of NER was undertaken using SSR markers, selected for their broad distribution throughout the genome, in order to assess the extent of allelic diversity among the lines and whether any population structure could be established. In addition to assessing molecular diversity, the study aims to evaluate the potential for yield and other beneficial and unique alleles that have high potential to contribute in the genetic enhancement programme of maize.

Study of Genetic Diversity and Population Structure of the Osetin Breed in Comparison with Other Coarse Wool Fat-Tailed Sheep Breeds Based on SNP Genotyping Data

Study of Genetic Diversity and Population Structure of the Osetin Breed in Comparison with Other Coarse Wool Fat-Tailed Sheep Breeds Based on SNP Genotyping Data

Study of Genetic Diversity and Population Structure of the Osetin Breed in Comparison with Other Coarse Wool Fat-Tailed Sheep Breeds Based on SNP Genotyping Data

For the first time, an analysis of the genetic diversity of the Osetin sheep breed was performed using genome-wide SNP profiles in a comparison with other Russian coarse wool breeds. We established that the Osetin breed has high genetic and allelic diversity indicators. For the first time, the recent and historical population effective sizes of the Osetin breed were calculated. Close genetic relationships between the Osetin and Karachaev sheep breeds were shown, that is confirmed by the low value of differentiation (Fst = 0.009) and the formation of a joint cluster at the Neighbor Net graph. The similarity of the population structure of the Osetin and Karachaev breeds was revealed as well.

Variance analysis for grain number related traits and study of population structure in rice (Oryza sativa)

Utilising average data from the rainy (kharif) seasons of 2021 and 2022, the genetic diversity of 188 recombinant inbred lines (RILs) of rice (Oryza sativa L.) was evaluated at the research farm of ICAR-National Rice Research Institute, Cuttack, Odisha. The grain number and associated 10 characteristics' coefficient of phenotypic variability was substantial, with the grain number per panicle having the greatest PCV and GCV. Principal component analysis was used to further identify the relationships and trends among the RILs. The first four primary components (74.58%) fully described the variability of all 10 features. Cultivars were divided into 8 groups based on the characters used to attribute grain number. To analyse genetic differences between RILs at the molecular level, 22 SSR markers were utilised and the PIC value was 0.709. A strong and significant relationship between them was shown by the structural analysis, with spikelet number and spikelet fertility per cent indicating a particularly strong correlation. Between clusters 1 and 3, there was considerable genetic variety, which offers great breeding options.

Automated machine learning for genome wide association studies.

Genome-wide association studies (GWAS) present several computational and statistical challenges for their data analysis, including knowledge discovery, interpretability, and translation to clinical practice. We develop, apply, and comparatively evaluate an automated machine learning (AutoML) approach, customized for genomic data that delivers reliable predictive and diagnostic models, the set of genetic variants that are important for predictions (called a biosignature), and an estimate of the out-of-sample predictive power. This AutoML approach discovers variants with higher predictive performance compared to standard GWAS methods, computes an individual risk prediction score, generalizes to new, unseen data, is shown to better differentiate causal variants from other highly correlated variants, and enhances knowledge discovery and interpretability by reporting multiple equivalent biosignatures. Code for this study is available at: https://github.com/mensxmachina/autoML-GWAS. JADBio offers a free version at: https://jadbio.com/sign-up/. SNP data can be downloaded from the EGA repository (https://ega-archive.org/). PRS data are found at: https://www.aicrowd.com/challenges/opensnp-height-prediction. Simulation data to study population structure can be found at: https://easygwas.ethz.ch/data/public/dataset/view/1/.

Morpho-cultural, pathological and molecular variability in Phloeospora maculans causing leaf spot of mulberry (Morus species) in India.

Leaf spot disease (LSD) of mulberry caused by Phloeospora maculans is a major threat to the silk industry of Jammu and Kashmir, India, therefore, it was necessary to study the population structure of the pathogen for successful management of the disease. To understand the diversity in the Phloeospora maculans, a combination of conventional (morphological, cultural and pathological) and molecular (ISSR markers) approaches were employed to discern the variability in 27 isolates collected from Srinagar, Bandipora, and Baramulla districts of Jammu and Kashmir, India. The studies revealed a high level of variability in the pathogen. Based on the morpho-cultural and pathological studies, the pathogen isolates were grouped into different categories based on colony growth, texture, margin and colour besides changes in colour of medium, incubation period, leaf area infected, etc.A high level of polymorphism was observed in different isolates of P. maculans using ISSR markers, which indicated that these markers are suitable for studying the genetic diversity in this pathogen. All the isolates (27) of P. maculans were clustered into two groups or populations as indicated by mean delta K value. Analysis of molecular variance revealed the low genetic variation among the populations (1.08%) and a high level of genetic variation within the populations (98.91%). Fst value was found to be 0.01 indicating smaller amount of genetic differentiation between the populations against calculated P-value of 0.29. A high level of diversity based on morphological, cultural, pathological and molecular levels was observed in Phloeospora maculans collected from various districts of Kashmir valley, which indicates that the study of population structure is necessary for successful management of the disease.

Genome-Wide Association Studies of Salt-Tolerance-Related Traits in Rice at the Seedling Stage Using InDel Markers Developed by the Genome Re-Sequencing of Japonica Rice Accessions

Japonica-specific markers are crucial for the analysis of genetic diversity, population structure, evolutionary traits, and genome-wide association study (GWAS) of japonica germplasm accessions. This study developed 402 insertion–deletion (InDel) polymorphic markers based on the re-sequencing of four japonica rice landraces and three japonica rice cultivars. These InDel markers were uniformly distributed across 12 rice chromosomes with high polymorphism and good amplification specificity. The average density of InDel markers on each chromosome was 0.95 Mb per locus. On the basis of these InDel markers, genetic diversity analyses and GWASs for 12 salt-tolerance-related traits were performed using 182 japonica rice accessions. In total, 1204 allelic variants were detected, with an average of 3.00 alleles and 2.10 effective alleles per locus. Based on population structure analysis, 182 japonica rice accessions were divided into four subgroups. The GWAS analyses revealed a total of 14 salt-tolerance-related InDels, which were located on chromosomes 1–5, 9, 10, and 12. Twenty-eight allelic loci were identified, explaining 6.83% to 11.22% of the phenotypic variance. Haplotype analysis detected six InDel markers associated with salt-tolerance-related traits that were significantly different (p < 0.05) or highly significantly different (p < 0.01) among different haplotypes. These markers can be utilized for the molecular identification of salt-tolerant rice germplasm accessions.

Assessing Genetic Variation among Strychnos spinosa Lam. Morphotypes Using Simple Sequence Repeat Markers.

Strychnos spinosa Lam., commonly known as green monkey orange, is a highly valued indigenous fruit tree in South Africa with potential for domestication and commercialization. However, no study has reported on the molecular diversity of Strychnos spinosa morphotypes. Therefore, this study aimed to determine genetic variation among 32 Strychnos spinosa morphotypes using simple sequence repeat (SSR) markers. Fourteen amplified SSR markers produced 159 alleles, with a mean of 5.68 per locus. The polymorphic information content (PIC) values ranged from 0.22 (Ssp_1) to 0.84 (Ssp_6). Morphotypes were clustered in a biplot based on their genetic distances. The dendrogram chiefly discriminated morphotypes according to variation of pericarp texture. The population structure had the highest delta value K = 3, thus the 32 morphotypes were divided into three subpopulations based on the Bayesian approach. The affinities produced by the population structure agreed with the genetic distance of closely related morphotypes. This study is the first to report on SSR marker development and their successful use for genetic diversity and population structure studies of Strychnos spinosa. It provides insights into the molecular characterisation of Strychnos spinosa. This can lead to breeding programs and crop improvement programs, particularly in varietal developmental programs, which can contribute to alleviating food security challenges.

Ecological niche affects mitochondrial DNA diversity and variation in near-threatened Himalayan vulture (Gyps himalayensis)

Abstract. Ummee C, Sitdhibutr R, Lertwatcharasarakul P, Kasorndorkbua C. 2023. Ecological niche affects mitochondrial DNA diversity and variation in near-threatened Himalayan vulture (Gyps himalayensis). Biodiversitas 24: 3630-3640. The impact from the use of diclofenac on the Indian subcontinent is the main reason why the Himalayan vulture Gyps himalayensis Hume, 1869 has near-threatened conservation status. In particular, it has ecological niches different from those of other vultures in the same genus; however, there has been no systematic study on genetic diversity. This study analyzed the genetic diversity of Himalayan vultures that had migrated to Thailand during the winter in conjunction with samples from a limited GenBank database. The results identified no evidence of Himalayan vulture genetic diversity loss after Gyps vultures were affected by diclofenac since the 1990s and the values were related to raptors with stable population status, which may be the result of ecological niche. Genetic differences or group divided were found in the mitochondrial DNA (mtDNA) Control Region (CR) and Cyt b+CR except in Cytochrome b (Cyt b). The group division based on the results of genetic distance between CR and Cyt b+CR shows that the genetic distance between groups of CR was 10-12 times greater than that of Cyt b (0.771±0.055-0.923±0.084 and 0.076±0.068, respectively) and the difference was also present when analyzed with the combined data set of Cyt b+CR (0.448±0.036). This is an important indicator for the possible study of population structure through phylogeography, because the Cyt b from other studies did not indicate any genetic differences between populations of Himalayan vulture and other Gyps vultures, which may update conservation proposals to be more accurate and effective.

DdRAD sequencing based genotyping of six indigenous dairy cattle breeds of India to infer existing genetic diversity and population structure

The present investigation aimed to identify genome wide SNPs and to carry out diversity and population structure study using ddRAD-seq based genotyping of 58 individuals of six indigenous milch cattle breeds (Bos indicus) such as Sahiwal, Gir, Rathi, Tharparkar, Red Sindhi and Kankrej of India. A high percentage of reads (94.53%) were mapped to the Bos taurus (ARS-UCD1.2) reference genome assembly. Following filtration criteria, a total of 84,027 high quality SNPs were identified across the genome of 6 cattle breeds with the highest number of SNPs observed in Gir (34,743), followed by Red Sindhi (13,092), Kankrej (12,812), Sahiwal (8956), Tharparkar (7356) and Rathi (7068). Most of these SNPs were distributed in the intronic regions (53.87%) followed by intergenic regions (34.94%) while only 1.23% were located in the exonic regions. Together with analysis of nucleotide diversity (π = 0.373), Tajima’s D (D value ranging from − 0.295 to 0.214), observed heterozygosity (HO ranging from 0.464 to 0.551), inbreeding coefficient (FIS ranging from − 0.253 to 0.0513) suggested for the presence of sufficient within breed diversity in the 6 major milch breeds of India. The phylogenetic based structuring, principal component and admixture analysis revealed genetic distinctness as well as purity of almost all of the 6 cattle breeds. Overall, our strategy has successfully identified thousands of high-quality genome wide SNPs that will further enrich the Bos indicus representation basic information about genetic diversity and structure of 6 major Indian milch cattle breeds which should have implications for better management and conservation of valuable indicine cattle diversity.

Genome-wide study of linkage disequilibrium, population structure, and inbreeding in Iranian indigenous sheep breeds.

Knowledge of linkage disequilibrium (LD), genetic structure and genetic diversity are some key parameters to study the breeding history of indigenous small ruminants. In this study, the OvineSNP50 Bead Chip array was used to estimate and compare LD, genetic diversity, effective population size (Ne) and genomic inbreeding in 186 individuals, from three Iranian indigenous sheep breeds consisting of Baluchi (n = 96), Lori-Bakhtiari (n = 47) and Zel (n = 47). The results of principal component analysis (PCA) revealed that all animals were allocated to the groups that they sampled and the admixture analysis revealed that the structure within the populations is best explained when separated into three groups (K = 3). The average r2 values estimated between adjacent single nucleotide polymorphisms (SNPs) at distances up to 10Kb, were 0.388±0.324, 0.353±0.311, and 0.333±0.309 for Baluchi, Lori-Bakhtiari and Zel, respectively. Estimation of genetic diversity and effective population size (Ne) showed that the Zel breed had the highest heterozygosity and Ne, whereas the lowest value was found in Baluchi breed. Estimation of genomic inbreeding using FROH (based on the long stretches of consecutive homozygous genotypes) showed the highest inbreeding coefficient in Baluchi and the lowest in Zel breed that could be due to higher pressure of artificial selection on Baluchi breed. The results of genomic inbreeding and Ne showed an increase in sharing haplotypes in Baluchi, leading to the enlargement of LD and the consequences of linkage disequilibrium and haplotype blocks confirmed this point. Also, the persistence of the LD phase between Zel and Lori-Bakhtiari was highest indicating that these two breeds would be combined in a multi-breed training population in genomic selection studies.

A pilot-scale comparison between single and double-digest RAD markers generated using GBS strategy in sesame (Sesamum indicum L.).

To reduce the genome sequence representation, restriction site-associated DNA sequencing (RAD-seq) protocols is being widely used either with single-digest or double-digest methods. In this study, we genotyped the sesame population (48 sample size) in a pilot scale to compare single and double-digest RAD-seq (sd and ddRAD-seq) methods. We analysed the resulting short-read data generated from both protocols and assessed their performance impacting the downstream analysis using various parameters. The distinct k-mer count and gene presence absence variation (PAV) showed a significant difference between the sesame samples studied. Additionally, the variant calling from both datasets (sdRAD-seq and ddRAD-seq) exhibits a significant difference between them. The combined variants from both datasets helped in identifying the most diverse samples and possible sub-groups in the sesame population. The most diverse samples identified from each analysis (k-mer, gene PAV, SNP count, Heterozygosity, NJ and PCA) can possibly be representative samples holding major diversity of the small sesame population used in this study. The best possible strategies with suggested inputs for modifications to utilize the RAD-seq strategy efficiently on a large dataset containing thousands of samples to be subjected to molecular analysis like diversity, population structure and core development studies were discussed.

On the usefulness of mock genomes to define heterotic pools, testers, and hybrid predictions in orphan crops.

The advances in genomics in recent years have increased the accuracy and efficiency of breeding programs for many crops. Nevertheless, the adoption of genomic enhancement for several other crops essential in developing countries is still limited, especially for those that do not have a reference genome. These crops are more often called orphans. This is the first report to show how the results provided by different platforms, including the use of a simulated genome, called the mock genome, can generate in population structure and genetic diversity studies, especially when the intention is to use this information to support the formation of heterotic groups, choice of testers, and genomic prediction of single crosses. For that, we used a method to assemble a reference genome to perform the single-nucleotide polymorphism (SNP) calling without needing an external genome. Thus, we compared the analysis results using the mock genome with the standard approaches (array and genotyping-by-sequencing (GBS)). The results showed that the GBS-Mock presented similar results to the standard methods of genetic diversity studies, division of heterotic groups, the definition of testers, and genomic prediction. These results showed that a mock genome constructed from the population's intrinsic polymorphisms to perform the SNP calling is an effective alternative for conducting genomic studies of this nature in orphan crops, especially those that do not have a reference genome.