We investigated the genetic diversity and structure of the 239 fixed lines with 47 simple sequence repeat (SSR) and 109 NGS-generated SNP markers evenly distributed in B. rapa genome. Phylogenetic analysis classified the vegetable fixed lines to four subgroups, with the three types forming a separate and relatively farther cluster. Population structure analysis identified four sub-populations corresponding to geographic origin and morphological traits, and revealed extensive admixture. The vegetable B. rapa fixed lines successfully developed in our study would be valuable materials for multinational B. rapa diversity resources establishment. Understanding the genetic diversity and population structure could be useful for utilization of the representing genetic variation and further genetic and genomic analysis.

Capsicum diversity is getting lower in modern crops because of the genetic erosion. In Capsicum, breeders have been mainly focused on agriculturally important traits such as disease resistances, high yield and pungency. This narrow breeding pool hampered to develop improved cultivars. It has become a hot issue to conservation of genetic diversity and exploitation of wild germplasm in Capsicum. However, although a large number of accessions are maintained in Capsicum germplasm collections, their use for crop improvement is limited by the scarcity of information on genetic diversity, population structure and proper phenotypic assessment. The identification of representative and manageable subset of accessions would facilitate access to the diversity available in large collections. A genome wide germplasm characterization using molecular markers can offer reliable tools for adjusting the quality and representativeness of core samples. We investigated patterns of molecular diversity at 48 single nucleotide polymorphisms (SNPs) in 4056 accessions from 11 Capsicum species from 89 different countries. Using these genetic variations and 32 different morphological traits, 250 core set was selected in whole Capsicum germplasm. The core collection could be a primary source for distributing germplasm to pepper breeders and other national programs as well as for evaluation

Amaranth (Amaranthus sp. L.) is an important group of plants that includes grain, vegetable, and ornamental types. Centers of diversity for Amaranths are Central and South America, India, and South East Asia, with secondary centers of diversity in West and East Africa. The present study was performed to determine the genetic diversity and population structure of 75 amaranth accessions: 65 from South America and 10 from South Asia as controls using 14 SSR markers. Ninety-nine alleles were detected at an average of seven alleles per SSR locus. Model-based structure analysis revealed the presence of two subpopulations and 3 admixtures, which was consistent with clustering based on the genetic distance. The average major allele frequency and polymorphic information content (PIC) were 0.42 and 0.39, respectively. According to the model-based structure analysis based on genetic distance, 75 accessions (96%) were classified into two clusters, and only three accessions (4%) were admixtures. Cluster 1 had a higher allele number and PIC values than Cluster 2. Model-based structure analysis revealed the presence of two subpopulations and three admixtures in the 75 accessions. The results of this study provide effective information for future germplasm conservation and improvement programs in Amaranthus.

본 연구는 강원도 농업기술원 옥수수연구소에서 튀김옥 수수 품종개발을 위하여 육성한 79개의 자식계통들에 대하 여 대표적인 분자마커인 SSR마커를 이용하여 집단구조 및 association mapping 분석을 실시하였다. 집단구조에 대한 분 석 결과에서 79개의 튀김옥수수 자식계통들은 groups I, II, III, IV, admixed group으로 구분되었다. 4개의 옥수수 자식 계통은 group I에 포함되었고, Group II는 총 17개의 자식계 통들이 포함되었다. 그리고 6개의 자식계통들은 Group III에 포함되었으며, 22개의 자식계통들은 Group IV에 포함되었 다. 그리고 admixed group에는 30개 옥수수 자식계통들이 포함되었다. 튀김옥수수 자식계통들에 대하여 50개 SSR 마 커와 10개의 양적 형질 사이에서 association mapping 분석 을 하였다. Q GLM 분석에서는 0.01의 유의수준에서 92개의 marker-trait association을 확인하였으며, 반면에 Q+K MLM 분석에서는 0.01의 유의수준에서 6개의 marker-trait association 을 확인되었다. 본 연구에서 79개의 튀김옥수수 자식계통들 에 대한 집단구조 및 association mapping 분석의 결과는 앞 으로 강원도농업기술원 옥수수연구소에서 튀김옥수수 품종개 발을 위한 계통 육성 및 교배조합 구성 등에 유용한 정보를 제공할 것으로 기대한다.

For the study of population genetic structure with mtDNA, it is essential to measure genetic diversity at each mtDNA regions. Also, to evaluate the variation according to the each region should follow as well as to see if there are differences. In this study, we delved into the variations and dendrogram among samples of seven mtDNA regions (NDⅡ, NDⅤ, NDⅣ, NDⅣL, NDⅥ, NDⅠ, 12SrRNA) from wild Pacific abalone, Haliotis discus hannai collected in Yeosu, Korea. The region with the highest genetic variation was NDⅣ region (Haplotype diversity = 1.0000, Nucleotide diversity = 0.010823) with two to five times higher variation than the others. Furthermore, the study to see if there is a difference between the regions of samples showed that similar aspects of dendrogram in NDⅡ and NDⅠ(divergence of 90% and 87%), which forms a group with hd4, 7, 8 and 10 at bootstrap support, based on 1000 replications. Also, pair-wise FST between clusters within the regions showed high values; 0.4061 (P=0.0000), 0.4805 (P=0.0000) respectively. Therefore we can infer that it is the most efficient and accurate way to analyze the region of NDⅣ with the highest variation in addition to the regions of NDⅡ and NDⅠ, which formed clusters with high bootstrap value, for study of population genetic structure in this species.

Our study is performed to confirm the level of genetic diversity and population structure with 80 maize inbred lines (40 waxy inbred lines and 40 flint inbred lines) and to explain the genetic basis of agronomic traits using an association mapping. The 200 SSR loci are confirmed a total of 1,610 alleles in total 80 maize inbred lines. The average number of alleles per locus was 8.05. The average GD was 0.72. The average PIC value was 0.68. The average MAF was 0.40. Population structure was revealed for K=2. Total 80 maize inbred lines were divided by groups I, II and admixed group. The 14 waxy inbred lines were assigned to group I. The 45 inbred lines include 5 waxy inbred lines and 40 flint inbred lines were contained to group II. The 21 waxy inbred lines were contained in the admixed group with lower than membership threshold 0.8. Association mapping between 200 SSR markers and 10 phenotypic traits of waxy/flint maize inbred lines were performed by Q GLM and Q+K MLM. In significant level at 0.01, 72 SSR markers were associated with 10 phenotypic traits using Q GLM. The 4 marker-trait association were detected in Q+K MLM. The results derived from this study will be used for designing efficient new maize breeding programs.

Amaranths (Amaranthus sp.) are cosmopolitan and include grain, vegetable, ornamental and weed types. Forteen simple sequence repeat (SSR) markers were used to analyze the genetic diversity of 59 accessions of cultivated amaranth from Asian countries. A total of 63 alleles were detected with an average of 4.5 per locus. The averaged values of gene diversity and polymorphism information content (PIC) were 0.35 and 0.33, respectively. Alleles per locus in accessions from South Asia was 4.35, whereas 2.93 and 3.79 alleles per locus were found in Nepal and India, respectively. The mean gene diversity in Central Asia and East Asia was 0.36 and 0.28, respectively, whereas the mean PIC values were 0.27 and 0.22, respectively. The genetic diversity and PIC of the India amaranths were higher than that of other Asian countries. The model-based structure analysis revealed the presence of three subpopulations, which was basically consistent with clustering based on genetic distance. An AMOVA analysis showed that the between-population component of genetic variance was less than 56.16% in contrast to 43.84% for the within-population component. The overall FST value was 0.56, reflecting genetic differentiation within Asian amaranths. These findings could be used for designing effective breeding programs aimed at broadening the genetic bases of commercially grown varieties.

Agastache rugosa, a member of the mint family (Labiatae), is a perennial herb widely distributed in East Asian countries. It is used in traditional medicine for the treatment of cholera, vomiting, and miasma. This study assessed the genetic diversity and population structures on 65 accessions of Korean mint A. rugosa germplasm based on inter simple sequence repeat (ISSR) markers. The selected nine ISSR primers produced reproducible polymorphic banding patterns. In total, 126 bands were scored; 119 (94.4%) were polymorphic. The number of bands generated per primer varied from 7 to 18. A minimum of seven bands was generated by primer 874, while a maximum of 18 bands was generated by the primer 844. Six primers (815, 826, 835, 844, 868, and 874) generated 100% polymorphic bands. This was supported by other parameters such as total gene diversity (HT) values, which ranged from 0.112 to 0.330 with a mean of 0.218. The effective number of alleles (NE) ranged from 1.174 to 1.486 with a mean value of 1.351. Nei's genetic diversity (H) mean value was 0.218, and Shannon's information index (I) mean value was 0.343. The high values for total gene diversity, effective number of alleles, Nei's genetic diversity, and Shannon's information index indicated substantial variations within the population. Cluster analysis showed characteristic grouping, which is not in accordance with their geographical affiliation. The implications of the results of this study in developing a strategy for the conservation and breeding of A. rugosa and other medicinal plant germplasm are discussed.

본 연구는 총 50개의 SSR primer를 이용하여 색소옥수수(색소종실 옥수수 12계통, 색소찰 옥수수 12계통) 및 비색소옥수수(종실옥수수 2계통, 찰옥수수 5계통) 계통들에 대하여 유전적 다양성, 계통유연관계 및 집단구조를 분석하였다.1. 그 결과 50 개의 SSR primer들은 색소 및 비색소옥수수 31계통들에서 총 282개의 대립단편을 증폭시켰으며, SSR primer들에서 증폭된 대립단편의 수는 최소 2개에서부터 최대 11개까지의 범위로 나타나 평균 5.64개가 증폭되었다. MAF(major allele frequency)는 0.23(bnlg279)에서 0.90(umc2338)의 범위로 나타나, SSR primer 당 평균 0.45개로 나타났고, 유전적 다양성(GD)값은 0.17(umc2338)에서 0.86(bnlg279)의 범위로 나타나, SSR primer 당 평균 0.67의 값을 나타내었다. 2. 31개의 색소 및 비색소옥수수 계통들의 집단구조를 분석한 결과, 이들 옥수수 계통들은 Groups I, II, III, IV, V, admixed로 구분되었다. Group I은 찰옥수수 1계통, 색소종실옥수수 1계통, 색소찰옥수수 5계통이 포함되었고, Group II는 찰옥수수 1계통, 색소찰옥수수 3계통이, Group III는 색소종실옥수수 3계통, Group IV는 색소종실옥수수 2계통이, Group V는 종실옥수수 2계통, 찰옥수수 2계통, 색소종실옥수수 5계통이 포함되어 있었다. 그리고 admixed group에는 찰옥수수 1계통, 색소종실옥수수 1계통, 색소찰옥수수 4계통 이 포함되어 있었다.3. UPGMA법에 의한 계통유연관계 분석 결과, 31개의 색소 및 비색소옥수수 계통들은 유전적 유사성 27.4%의 수준에서 크게 3개의 그룹으로 나누어졌다. Group I은 10개의 옥수수 계통(종실옥수수 2계통, 찰옥수수 2계통, 색소종실옥수수 6계통)을 포함하고 있었고, Group II는 20개의 옥수수 계통(찰옥수수 3계통, 색소종실옥수수 5계통, 색소찰옥수수 12계통)을, 그리고 Group III은 색소종실옥수수 1계통을 포함하고 있었다. 따라서 본 연구의 결과는 앞으로 강원도 농업기술원 옥수수시험장에서 색소옥수수 자식계통들에 대한 선발과 품종 육성 연구에 유용한 정보를 제공할 것으로 생각된다.

The genus Rubus belongs to the Rosaceae family and is comprised of 600-800 species distributed worldwide. Understanding the genetic relationships and genetic structure in Rubus species is important for enabling efficient management, conservation, characterization and utilization of the species. However, as a minor crop, genetic research foundation was limited to explore genetic diversity and relationships in Rubus species. The present study shows the results of application SSR markers that were developed from SSR-enriched libraries of the one Rubus species (Rubus coreanus Mique.) in our previous study. We used 34 polymorphic microsatellite markers to analysis of genetic diversity within the Rubus species, including redraspberry, blackraspberry, blackberry and mountainberry. All the 34 SSR primers pairs produced 483 polymorphic and reproducible amplification fragments. The largest number of alleles per primer pair was confirmed at GB-RC-167, GB-RC-100, GB-RC-076 and GB-RC-245, which contained 26, 25, 23 and 21, respectively. An average value of polymorphic information contents (PIC) were 0.74 with a range of 0.36 to 0.92. Population structure and phylogenetic analyses showed that all Rubus species formed three largely distinct clusters, which were confirmed by principal coordinate analysis (PCoA). We obtained the results that the developed SSR markers showed a substantial degree of genetic diversity in the various Rubus species distributed in Korea.

In this study, 18 simple sequence repeat (SSR) primer sets were used to analyze the genetic diversity, genetic relationships, and population structure among 96 accessions of the two cultivated types of Perilla crop and their weedy types in East and Southeast Asia. A total of 168 alleles were identified at all the loci with an average of 9.3 and a range between 3 and 18 alleles per locus. Of the 168 alleles, 21 alleles (12.5%) were private, 67 alleles (39.9%) were rare (frequency < 0.05), 96 alleles (57.1%) were detected at an intermediate frequency (range, 0.05 - 0.50), and five alleles (3.0%) were abundant (frequency > 0.50), respectively. The gene diversity values varied from 0.443 to 0.898 with an average of 0.749. The PIC values varied from 0.397 to 0.890 with an average of 0.721. The gene diversity of each locus for accessions of cultivated var. frutescens, weedy var. frutescens, cultivated var. crispa, and weedy var. crispa were respectively showed 0.662, 0.744, 0.540, and 0.584. On the analysis of population structure using software program STRUCTURE 2.2, the 96 Perilla accessions were divided into Groups I, II, and admixed group. The phylogenetic tree revealed that the 96 accessions cluster into three major groups. No clear geographic structure and also between two cultivated types of Perilla crop and their weedy types were detected. The present study has demonstrated the utility of SSR analysis for the study of genetic diversity, genetic relationships and population structure among 96 accessions of the two cultivated types of Perilla crop and their weedy types in East and Southeast Asia. In our study, SSR markers helped improve our understanding of the genetic diversity, genetic relationships, and population structure of the two cultivated types of P. frutescens and their weedy types in East and Southeast Asia.

Buckwheat (Fagopyrum esculentum Moench), one of the minor crops grown in Korea belonging to the Polygonaceae family, is an annual crop widely cultivated in Asia, Europe, and America and has a character of outcrossing and self-incompatibility. The objective of this study was to analyze the genetic variability, phylogenetic relationships and population structure of buckwheat landraces of Korea using SSR markers. Ten microsatellite markers have been detected from a total of 79 alleles among the 179 buckwheat accessions were collected from Korea. The number of allele per marker locus (NA) ranged from 2 (GB-FE-001, GB-FE-043 and GB-FE-055) to 31 (GB-FE-035) with an average of 7.9 alleles. GB-FE-035 was the most polymorphic with the highest PIC value 0.93. Major allele frequencies (MAF) for the 10 polymorphic loci varied from 0.12 to 0.97 with a mean allele frequency of 0.57. The expected heterozygosity (HE) values ranged from 0.05 to 0.94 with an average of 0.53. The observed heterozygosity (HO) ranged from 0.06 to 0.92 with an average of 0.42. The overall polymorphic information contents (PIC) values ranged from 0.05 to 0.93 with an average of 0.48. The landrace accessions of buckwheat used in the present study were not distinctly grouped according to geographic distribution. The study concludes that the results revealed genetic differentiation was low according to the geographic region because of outcrossing and self-incompatibility. We reported that our analyses on the genetic diversity of common buckwheat cultivars of Korea were performed by using of microsatellite markers.

본 연구는 총 50개의 SSR 마커를 이용하여, 찰옥수수 및 종실용 옥수수 핵심집단(찰옥수수 40계통, 종실용 옥수수 40계통)의 자식계통들의 유전적 다양성, 집단구조 및 계통유연관계를 분석하였다. 1. 그 결과 65bp에서 225bp 크기의 범위로 총 242개의 대립단편들을 증폭시켰다. SSR primer들에서 증폭된 대립단편의 수는 최소 2개에서부터 최대 9개까지의 범위로 나타났고, 평균 4.84개가 증폭되었다. 그리고 GD값은 0.420에서 0.8

In application and discussion of population structure and phenotypic divergence in plant community, the classic Lotka-Volterra models of competition and spatial model are conceived as a mechanism that is composed by multiple interacting processes. Both the Lotka-Volterra and spatial simulation formulae predict that species diversity increases with genotypic richness (GR). The two formulae are also in agreement that species diversity generally decreases within increasing niche breadth (NB) and increases with increasing potential genotypic range (PGR). Across the entire parameter space in the Lotka-Volterra model and most of the parameter space in the spatial simulations, variance in community composition decreased with increasing genotypic richness. This was, in large part, a consequence of selecting genotypes randomly from a set pool.

In this study, 15 simple sequence repeat (SSR) markers were used to analyze the population structure of 55 mungbean accessions (34 from South Asia, 20 from West Asia, 1 sample from East Asia). A total of 56 alleles were detected, with an average of 3.73 per locus. The mean of major allele frequency, expected heterozygosity and polymorphic information content for 15 SSR loci were 0.72, 0.07 and 0.33 respectively. The mean of major allele frequency was 0.79 for South Asia, and 0.74 for West Asia. The mean of genetic diversity and polymorphic information content were almost similar for South Asian and West Asian accessions (genetic diversity 0.35 and polymorphic information content 0.29). Model-based structure analysis revealed the presence of three clusters based on genetic distance. Accessions were clearly assigned to a single cluster in which >70% of their inferred ancestry was derived from one of the model-based populations. 47 accessions (85.56%) showed membership with the clusters and 8 accessions (14.54%) were categorized as admixture. The results could be used to understanding the genetic structure of mungbean cultivars from these regions and to support effective breeding programs to broaden the genetic basis of mungbean varieties.

In this study, 29 simple sequence repeat (SSR) markers were used to analyze the genetic diversity and population structure of 125 rice accessions from 40 different origins in Africa, Asia, Europe, South America, and Oceania. A total of 333 alleles were detected, with an average of 11.5 per locus. The mean values of major allele frequency, expected heterozygosity, and polymorphism information content (PIC) for each SSR locus were 0.39, 0.73, and 0.70, respectively. The highest mean PIC was 0.71 for Asia, followed by 0.66 for Africa, 0.59 for South America, 0.53 for Europe, and 0.47 for Oceania. Model-based structure analysis revealed the presence of five subpopulations, which was basically consistent with clustering based on genetic distance. Some accessions were clearly assigned to a single population in which >70% of their inferred ancestry was derived from one of the model-based populations. In addition, 12 accessions (9.6%) were categorized as having admixed ancestry. The results could be used to understanding the genetic structure of rice cultivars from these regions and to support effective breeding programs to broaden the genetic basis of rice varieties.