Background : Recently, there is an urgent demand for development of new varieties with enhanced resistance to various biotic/abiotic stresses. One generation of ginseng is four years, so it takes a long time to breed. To increase the efficiency of the ginseng breeding and save time and effort, it is necessary to build a ginseng core collection. This study examined the major growth characteristics of genetic sources for the establishment of core collection. Methods and Results : As plant materials, 187 ginseng lines collected in 2003 were used in this study. Ginseng Seeds were harvested at the end of July 2014, sown in mid-November, and cultivated in 2015 for one year in the field and then transplanted into the main field in 2016. All phenotypes including agronomic characteristics, seed yield, and physiological response to biotic/abiotic stresses were investigated according to the ginseng GAP and UPOV guidelines. The stem colors of the collected ginseng germplasm were classified as the five classes; light green, green, light purple, purple and dark purple, but most of them were purple or dark purple. The locations of distribution of anthocyanin coloration in stem were classified into the four classes; proximal end, proximal end and petiole part, the entire stem and the stem with purple not revealed, but most of them were petiole part or the entire stem. The shapes of leaflet were classified the four classes; the long elliptic, elliptic, slender type, and spatulate type. Most of surveyed lines were elliptic type. When the leaflet of ginseng was laterally cut, the shape was classified into the three types; concave type, plane type and convex type. Most of surveyed lines were red berry color. Conclusion : The genetic pool of ginseng is known to be narrow. The results of this study showed similar characteristics among the ginseng fields collected. In the future, we will carry out the survey about quantitative characteristics and correlations of ginseng genetic resources for establishment of Korean ginseng core collection.

GWAS (Genome-wide association study) provides a useful to associate phenotypic variation to genetic variation. It has emerged as a powerful approach for identifying genes underlying complex diseases or morphological traits at an unprecedented rate. Despite benefits, there are only a few examples applied in crop plants due to lack of effective genotyping techniques and well prepared resources for developing high density haplotype maps. In this study, 350 core accessions selected from almost 5,000 Capsicum accessions were used for GWAS. We are planning to construct a high-density haplotype map using GBS platform and perform GWAS for various agronomic traits including fruit traits and metabolites related to pungency to identify genes controlling the traits. These results will not only provide a list of candidate loci but also a powerful tools for finding genetic variants that can be directly used for crop improvement and deciphering the genetic architecture of complex traits.

Sesame (Sesamum indicum L.) is one of the most important oilseed crops with high oil contents and rich nutrient value. The development of a core collection could facilitate easier access to sesame genetic resources for their use in crop improvement programs and simplify the genebank management. The present study was initiated to the development and evaluation of a core collection of sesame based on 5 qualitative and 10 quantitative trait descriptors on 2,751 sesame accessions. The accessions were different countries of origin. About 10.1 percent of accessions were selected by using the power core program to constitute a core collection consisting of 278 accessions. Mean comparisons using t-test, Nei’s diversity index of 10 morphological descriptors and correlation coefficients among traits indicated that the existing genetic variation for these traits in the entire collection has been preserved in the core collection. The results from this study will provide effective information for future germplasm conservation and improvement programs in sesame.

네덜란드 와게닝건대학 식물육종연구실에서는 배추과 채소들을 형태적 지리적 근원을 찾아 대표 형태형을 나타 내는 수집단을 분류하는 Core Collection 연구가 이루어지고 있다. 배추과 채소들은 대부분 Heterogeneous 하고, Heterozygous 하기 때문에 본 실험실에서는 와게닝건 대학으부터 배추과 채소 중 8개의 형태형을 나타내는 19계통 (Chinese Cabbage 3계통, Chinese Turnip Cabbage 2계통, Pak Choi 3계통, Turnip 5계통, Broccolleto 3계통, Mizuna 1계 통, Komatsuna 1계통, Turnip green 1계통)을 분양 받아서 소포자배양을 진행 하였다. 소포자배양를 진행한 결과, 8 가지 종들 중, Komatsuna 와 Turnip Green을 제외한 6종에서 모두 배의 발생을 유도 할 수 있었고, 유도된 배들은 식 물체로의 재생을 위해 MS배지에 옮겨졌고, 토양순화, 저온처리 의 과정을 거쳤다. 이들 6종들 중 Broccolleto를 제 외한 5종에서 채종이 가능하였다. 배추과 채소의 Core Collection을 위한 19계통의 소포자배양 결과, 10계통에서 배 가 유도되었으며, 발생된 배의 개체 수에는 차이가 크게 나타났으나, MS 배지로 옮겨진 배들은 10계통 모두에서 정상적인 뿌리를 형성한 Adventitious shoot가 재생되었고, 토양에 4주 이상 적응한 식물체를 획득할 수 있었다. 10 계통 중 2계통을 제외한 8계통이 4주 동안 저온처리의 과정에 적응하였고, 이들 중 7계통에서 채종과정을 거쳐 종 자생산에 성공하였다.

Glucosinolates of Brassica rapa collection from Korea genebank were measured to determine total glucosinolate content and their variation of diverse glucosinolates; Around 100 accessions representing the different morphotypes and geographical origin of Brassica rapa were analysed. The principal component analysis was performed to evaluate the differences among morphotypes using the profiles of 14 glucosinolates identified from the leaves. DMRT test and box plots showed the significant difference between total glucosinolates of subspecies. Most of turnip accessions had higher gluconilates compared to the other type accessions, Chinese cabbage and pak choi. These accessions will be used for GWAS study for glucosinolate. Now they are being finger-printed by genotyping by sequencing (GBS). Among these accession, we selected a turnip accession with high amount of glucosinolate, K0466 and two Chinese cabbage accession with low amount of glucosinolate, K0015 and K0621. To analyse quantitative traits loci (QTL) for glucosinolate synthesis, these three accessions were fixed through microspore culture. Finally, six homozygous lines were selected and were crossed each other to make F1 hybrids. We just harvested F2 seeds and transferred doubled haploid plants to pots. QTL analysis for glucosinolate will be performed these F2 and DH population.

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. However, 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. Analysis of genetic diversity and construction of core collection is the first step to make efficient use of germplasm. Although there have been several attempts to construct core collections in Capsicum, most of these works were limited due to handling small number of samples, relying mainly on the characterization of morphological traits or focusing only C. annuum species. To expand understanding of the structure and genetic diversity of germplasm in Capsicum, we need to have a highly efficient genotyping tool to handle large number of samples. Toward this end, we are analyzing 3,599 germplasm accessions including other cultivated species and wild species in Capsicum with 48 single nucleotide polymorphism (SNP) markers.

For genetic mapping studies, biparental segregating populations are often useful, however recombination is limited, giving rise to large genomic regions under QTL, and one can only study alelles present in both parents. In Wageninegn UR, a core collection is being developed representing all Brassica rapa morphotypes and geographic origins. As most B. rapa accessions are heterozygous and heterogeneous, we started a project to fix the collection through microspore culture. The resulting Diversity Fixed Foundation Set will be an interesting resource for association mapping studies, which have as advantage that they present the allelec variation present in the collection, and for mapping studies recombination is increased. Nineteen accessions of eight subspecies of Brassica rapa were used for microspore culture to developdoubled haploid lines. Eight morphotypes were represented: 3 Chinese cabbage, 2 Chinese turnip cabbage, 3 Pak choi, 5 Turnip, 3 Broccolleto, 1 Mizuna, 1 Komatsuna and 1 Turnip greenfrom the 19acessions examined, embryos were obtained for 13, representing six subspecies (Komatsuna and Turnip Green had no response). The embryo yields differed significantly between these 13 accessions. We regenerated normal plants from 10 accessions that survived more than 4 weeks in the soil using microspore culture. Nine accessions flowered after 4 weeks vernalization at 5℃ and seeds were harvested from 5 accessions. From a Mizuna, we obtained 3791 seeds from one plant and total 7318 seeds were harvested from 5 accessions representing 4 subspecies(Chinese cabbage, Chinese turnip cabbage, Pak choi, Mizuna). At present, we carry out experiment for obtain more seeds and induce embryos from the other plant materials.

We have identified ATTIRTA1 transposon, a kind of mariner-type DNA transposon from Brassica rapa genome. A total of 811 inverted-terminal repeat, ITR consisting of the both terminal on ATTIRTA1 transposon were found from B. rapa v1.1 sequence. Among them 616 ITR were paired by two in each transposon, indicating three quarters of the transposon exists in original form. Around 10 percentage of the transposon, 82 ITR was located in gene, expecially only in intron. Using these ATTRRTA1, we developed a display system modified from AFLP technique and applied for this system to analyze genetic diversity of Korea Brassica rapa core collection. The collection includes 220 accessions representing the different morphotypes and geographical origin. The analysis of population structure revealed five subgroups and the clustering patterns matched well with their morphological traits. ATTIRTA1 transposon display seems useful marker system for studying genetic relationships. Presently we have profiled the components and contents of glucosinolate in the core collection to analyze genome wide association. This collection will be helpful to identify agriculturally desirable traits from other supspecies.

Cowpea might have been introduced from China to Korea and cultivated for several hundred years but it has never been a staple food crop in Korea. In this study, genetic diversity of 492 Korean cowpea landrace accessions that have passport information was estimated using six SSR markers. The mean of Weir's gene diversity was 0.665 from all accessions investigated in the study. Cowpea gene diversity of six local provinces in Korea was ranged from 0.370 in accessions of Gangwon to 0.680 in Jeonra provinces. Low gene diversity of the cowpea genepool of Gangwon province was probably derived from relatively few introductions. Especially SSR markers VM36 and VM39 seem to be good markers to distinguish the Gangwon accessions from others by occurring at a specific locus with higher than 78% of allele frequency. Except for the Gangwon province with the low genetic diversity, gene diversity of cowpea accessions from other provinces was ranged from 0.600 to 0.680 indicating no big differences among provinces. Distribution pattern of the allele frequencies was similar among the other provinces. This may reveal that Korean farmers might exchange cowpea seeds easily with even their neighbors with geographical barriers. A core collection, 100 landraces, ca. 20% of base collection, was developed at the 70% of a similarity coefficient level using random sampling approaches after stratification of the entire landrace collection based on the phenetic dendrogram. The variability of SSR in the base and core collections of Korean cowpea landrace was compared by calculating Weir's gene diversity. The mean of Weir's gene diversity of the core was 0.707 while that of the base collection was 0.665. The higher diversity index in the core collection indicates that it maintains the initial variability and well represents the base collection. The core collection included one of determinate accession (IT 216155) and two of no branching type accessions (IT 103959 and IT 161024). The core collection could be used to guide more efficient management and utilization of the entire collection. This core collection should be revised periodically as additional accessions are collected and further characterization is conducted.