Phosphine (PH3) fumigation has been widely used for controlling storedgrain insect pests, causing the development of resistance of stored-grain insect pests to phosphine. PH3 resistance in Sitophilus oryzae has been reported in Korea. However, PH3 resistance in Tribolium castaneum has not been reported yet. This study was conducted to determine susceptibilities of T. castaneum collected from five different domestic locations to PH3. The susceptibility to PH3 was investigated using the FAO fumigation method. All domestic T. castaneum individuals were controlled by PH3 at 0.04 g m-3. At 0.01 g m-3, T. castaneum collected from two domestic locations did not exhibit 100% mortality. A P45S point mutation in dihydrolipoamide dehydrogenase (dld) gene was found in a PH3-resistant strain of T. castaneum (Aus07), but not in five domestic stains or a PH3-susceptible strain (Aus10). No significant difference was found in dld or cyt-b5-r gene expression across all tested strains. However, the Gyeongju-collected strain of T. castaneum showed more than a 1.7-fold increase in cyt-b5-r expression compared to the Aus07 strain. cDNA sequence analysis revealed that P45S (C133T) in the dld gene was only present in Aus07. A characteristic single nucleotide polymorphism in the cyt-b5-r gene sequence was identified in the five domestic strains. This study suggests that it is necessary to continuously monitor PH3-susceptibility of T. castaneum in Korea to quickly identify resistant individuals and prevent the spread of PH3 resistance through rapid control.
Bacterial phytopathogen Pectobacterium causes soft rot disease in several vegetable crops globally, resulting in heavy agricultural losses at both the pre and postharvest stages. The present work was carried out to screen Kimchi cabbage genetic resources conserved at the National Agrobiodiversity Center, Rural Development Administration, Korea, for resistance against the soft rot pathogen Pectobacterium carotovorum subsp. carotovorum KACC 21701 over a period of three years (from 2020 to 2022). Infection of the phytopathogen was carried out at four-leaf stage and for each accession, twenty-five plants per germplasm were infected with KACC 21701. Kimchi cabbage cultivars Wangmatbaechu, Seoulbaechu, and CR Kiyoshi were used as control. Seven-days post-infection, the Disease Index (DI) values were manually recorded from zero to four, zero matched perfectly heathy plants and four completely dead plants. The 682 accessions of Kimchi cabbage exhibited varying degrees of disease resistance to KACC 21701 and thirty accessions, exhibiting a DI≤2, were considered for replication studies. During the replication studies, four landrace germplasms (IT102883, IT120036, IT120044, and IT120048) and one cultivar (IT187919) were confirmed to be moderately susceptible to KACC 21701. Results of the preliminary screening as well as replication studies were documented for the all the 682 germplasms. Addition of such information to the passport data of stored germplasms might serve as potential bio-resource for future breeders and researchers to develop resistant varieties or study the mechanisms involved in resistance of plants to such phytopathogen.
본 연구에서는 한국에서 개발한 23개의 양송이 품종과 42개의 도입품종의 유전적 다양성과 집단 구조를 SSR 마커를 이용하여 분석하였다. 양송이 품종의 NA는 약 13, HO는 약 0.59, HE는 약 0.74, PIC값은 약 0.71 이었다. 양송이 품종은 군집분석에 의하여 3개의 Group으로 구분되 었고 다양한 국가의 품종으로 구성된 Group2의 다양성이 높았으며, 구조분석에 의하여 2개의 subpopulation으로 구분되었고, 품종의 수가 많은 Pop2의 다양성이 높았다. 한국의 양송이 품종들은 주로 Group 3에 분포하고, subpopulation 간 분포에는 큰 차이를 보이지 않았다. 본 연구의 결과는 양송이의 육종소재의 개발, 다양성 확보 등과 같은 품종의 개발과정에 이용될 수 있을 것이다.
본 연구는 국내 염습지 해안 복원의 주요 식물인 갈대와 내건성 대표 식물인 억새의 지역별 유전자형 분석을 통해 지역별 복원종자 적용에 대한 타당성을 검증고자 하는 연구로서, SNP를 활용한 근연관계 분석 결과 억새는 홍성군 집단이 다른 지역과 상이한 유전적 변이를 보인 반면, 갈대는 모든 지역에서 동시다발적인 변이양상이 나타낸다. 이를 통하여 억새의 경우 우리나라 전역에 발생하는 건조지에서 억새시료를 사용할 때는 지역별로 수집한 종자를 활용하는 것이 합리적이나 부득이하게 다른 지역의 식물 자원을 사용한다고 해도 유전적인 교란이 크게 발생하지 않을것으로 보인다. 갈대의 경우 전 지역에서 유전적 변이가 다양하며 억새에 비하여 유전적 변이가 상대적으로 많이 나타나고 있기 때문에 염류 피해지의 복원에 활용할 수 있는 자원인 갈대의 경우 종자를 지역별로 수집하기 위한 다양한 인프라를 구축하여 향후 복원 사업에 대비하여야 한다.
Sesame is queen of oil seed crops and widely cultivated in Asia and Africa. The aim of this study was to develop a mini sub core set representing the diverse germplasm of sesame and to assess the genetic diversity, population structure and phylogenetic relationship of the resulted sub core set to be used in whole genome resequencing platform. One hundred twelve accessions out of 277 accessions were selected by the PowerCore program. A total of 155 alleles were captured from the 158 alleles detected in the primary core population, and rare alleles and specific alleles were also maintained in the sub core set accessions representing almost 100% of the primary core population. Among the sub core set accessions, four sub populations were observed with some admixture accessions. Although the genetic diversity of Pop-1 which includes most accessions from Korea is relatively lower than that of other three sub populations, it can maintain maximum number of accessions in the sub core set with the same percentage as in the primary core set probably because of the specific features of these accessions. Based on this framework of genetically defined populations, the effective use and conservation management of Sesamum indicum for crop improvement might be possible.
Meedon rice varieties are important for local adaptability, grain quality and market availability, and have been grown in Myanmar for centuries. Because of temporal variability and spatial heterogeneity, Meedon rice varieties in rainfed lowland areas may be diverse. However, information on diversity of Meedon rice germplasm is limited. This study was carried out to assess genetic diversity and to analyze population structure of Meedon rice germplasm conserved in Myanmar Seed Bank using SSR markers. For assessing genetic diversity, 154 accessions of Meedon rice germplasm were analyzed with nine SSR markers. A total of 86 alleles were detected with an average of 9.6 alleles per locus. All the loci were found to be polymorphic, and there were considerable genetic variation among accessions with mean values of expected heterozygosity (HE) = 0.5774 and polymorphic information content (PIC) = 0.5496. High frequency of rare alleles was identified, among which 35 unique (accession-specific) alleles were observed. Based on cluster analysis, rice accessions were mainly clustered into two groups, and as a result of model-based analysis, two distinct genetic populations and an admixture were classified. This result indicated that SSR markers have proved to be useful markers for detecting genetic diversity in Meedon rice, and the occurrence of a considerably high number of rare and unique alleles in the germplasm indicates their potentiality as a reservoir of rare genotypes for use. Unique alleles are also important because they may be diagnostic of a particular type of genotype for identification.
본 연구는 멸종위기식물인 단양쑥부쟁이(Aster altaicus var. uchiyamae)의 개체군을 대상으로 유전다양성을 유지하는데 필요한 최소개체수를 산정하기 위하여 수행되었다. 단양쑥부쟁이가 분포하고 있는 네 지역에서 각각 유전다양성 및 유전적 분화도를 분석하였다. AFLP(amplified fragment length polymorphism) 마커를 이용한 유전적 변이의 분석결과, 총 4개의 프라이머 조합에 대해서 936개의 밴드가 확인되었으며, 그 중 934개의 밴드(99.8%)가 다형성을 보여주었다. 단양쑥부쟁이 개체군 내에서 유전다양성(PPB = 45.3%, h = 0.104, I = 0.168, hs = 0.108)은 높은 수준으로 나타났으며, 개체군 간 유전적 분화도(GST = 0.075, θB = 0.079)는 낮은 수준이었다. AMOVA(Analysis of molecular variance)분석 결과에서도 전체 유전적 변이 중 91%가 개체군 내에서 보이는 반면, 9%는 개체군 간 변이에 기인한 것으로 나타났다. 단양쑥부쟁이 개체군에서 보이는 유전적 특성은 개체군 간의 빈번한 유전자 이동에 기인한 것으로 사료된다. 최대화 전략법에 의하여 경기도 여주일대의 3개 개체군을 대상으로(굴암, 도리섬, 삼합) 개체군 내 최소개체수를 산정한 결과 도리섬개체군에서는 17개체, 삼합개체군에서는 16개체, 굴암개체군에서는 11개체로 파악되었다. 단양쑥부쟁이 개체군의 최소개체수에 대한 정보는 효율적인 현지 외 보전을 위한 가이드라인을 제시해 줄 수 있다.
Hedera helix 11계통, Hedera rhombea 3계통, Fatshedera lizei 1계통, 그리고 Fatsia japonica 1계 통을 수집하였다. RAPD primer 10개를 이용하여 수 집된 3속의 재료들의 유전적 다양성을 측정하였다. 3 속을 재료로 사용하여 밴드간 96.9%의 높은 다형성을 보였다. 총 97개의 RAPD 밴드를 이진화하여 UPGMA 방법을 이용하여 계통도를 작성하였다. Hedera helix 계통들은 모두 1개의 그룹에 속하였으며 8계통의 유전 적 거리는 극도로 적었으며 나머지 3계통 역시 유전적 으로 가까웠다. 하지만 형태적으로는 높은 다형성을 보 였다. 따라서 수집된 유전자원을 이용한 돌연변이체 개 발이 가능성이 있는 방법으로 제시되었다. Fatsia japonica는 유전적으로 관계성이 적어 다른 종들과 평 균 0.63의 유전적 거리를 보였다. Hedera helix와 Fatsia japonica 속간 교배를 통하여 개발된 Fatshedera lizei는 Hedera rhombea 계통들과 함께 계통도에서 위치하였다.
In crop breeding program, information about genetic dissimilarity on breeding resources is very important to corroborate genealogical relationships and to predict the most heterozygotic hybrid combinations and inbred breeding. This study aimed to evaluate the genetic variation in Kenyan sunflower breeding lines based on simple sequence repeat (SSR). A total of 83 alleles were detected at 32 SSR loci. The allele number per locus ranged from 2 to 7 with an average of 2.7 alleles per locus detected from the 24 sunflower accessions and the average value of polymorphic information contents (PIC) were 0.384. A cluster analysis based on the genetic similarity coefficients was conducted and the 24 sunflower breeding resources were classified into three groups. The principal coordinates (PCoA) revealed 34% and 13.38% respectively, and 47.38% of total variation. It was found that the genetic diversity within the Kenyan sunflower breeding resources was narrower than that in other sunflower germplasm resources, suggesting the importance and feasibility of introducing elite genotypes from different origins for selection of breeding lines with broader genetic base in Kenyan sunflower breeding program.
Little millet (Panicum sumatrense) is well known for its salt and drought stress tolerance and high nutritional value, but very limited knowledge of genetic variation and genomic information is available. In this study, a total of 779 primer pairs were designed from the 22,961 EST sequences of switchgrass (Pancium virgatum), of which 48 EST-SSR markers were developed based on the trials of transferability of these primers in little millet. The EST-SSR amplicons showed reproducible single band polymorphism and produced a total of 160 alleles with an average of 3.3 alleles per locus in 37 accessions of little millet. The average values of expected and observed heterozygosities were 0.266 and 0.123, respectively. The polymorphic information content (PIC) values were observed in range of 0.026 to 0.549 with an average of 0.240. The genetic relatedness among the little millet accessions was evaluated by neighbor-joining dendrogram, which grouped all accessions into two distinct groups. The validation thus demonstrated the utility of the switchgrass EST-SSR markers in assessing genomic relationships in little millet. The findings from this study could be useful for designing strategies for the identification of diverse germplasm for conservation and future molecular breeding programs for little millet.
Eleven RAPD primers were assessed to analyze genetic diversity of Korean wheat varieties and to develop DNA marker for cultivar identification. The average of the number of polymorphic bands was 5.2 and PIC values showed 0.48, respectively. Ten major clades were presented by phylogenetic analysis. Three cultivars containing Uri, Hanbeak and Jonong were distinct from the others in the phylogenetic dendrogram. Seven cultivar-specific fragments were detected from 11 RAPD fingerprinting among 35 wheat cultivars and they were sequenced. Four Korean wheat cultivars, Eunpa, Jopoom, Yeonbaek and Jeokjoong, were identified newly by four markers, 84, 173, 174 and KWSM011. We convince that these new DNA markers are useful for cultivar fingerprinting and are applied to marker-assisted selection in wheat breeding program.
Pepper (Capsicum spp.) germplasm shows diverse phenotypic variations including fruit size, color, pungency, and many other horticultural traits. Traditional markers including SSR, AFLP, and RFLP have been used to construct genetic maps using biparental populations. However to assess the genetic diversity of large number of germplasm, a robust and rapid marker development and genotyping approach is needed. We used six pepper accessions including C. annuum, C. chinense, C. baccatum and C. frutescens and performed genotyping-by-sequencing (GBS). To select the most appropriate condition, eight different 2 bp selective nucleotides were used to make GBS libraries. Selective nucleotide ‘OO’ showed the largest number of reads in all samples, and 11,026 to 47,957 high-quality SNPs were called in six accessions. When C. annuum ‘CM334’ genome sequence was used as a reference, C. annuum showed the smallest number of SNPs, while C. baccatum which was known to be a different Capsicum clade showed the largest number of SNPs. Pepper core collection chosen to represent the genetic diversity of whole germplasm will be genotyped by high-density SNPs developed from GBS. We will perform genome-wide association study (GWAS) using genetic and phenotypic variation to identify the functional genetic loci controlling horticultural traits.
Grain sorghum is the fifth most important crop grown in the world for either a major food crop or animal feed. It is important to identify the genetic diversity of sorghum genetic resources for cultivar development and evaluation of sorghum accessions in Korea. Two hundred thirty six SSR primer sets, which are evely distributed across the sorghum genome, were used to assess the genetic variation of 23 sorghum accessions with a US cultivar, BTx623. Results showed that SSR markers were highly polymorphic among the sorghum collections and the average alleles per locus were 3.15 with the average of 0.436 PIC (polymorphism information content) values. The sorghum accessions in this study were unequally separated and were clustered into 4 groups. The results showed that there was a sufficient SSR polymorphism with SSR primers used among Korean sorghum accessions, and the development of genetic map and marker-assisted selection for cultivated sorghum would be feasible with further studies.
The objective of this study was to analyze the genetic diversity using SSR marker and investigate the fatty acid composition of perilla (P. frutescens var. frutescens) germplasm. Genetic diversity among 95 accessions, which consisted of 29 weedy types and 66 landrace accessions, was evaluated based on 12 SSR markers carrying 91 alleles. The mean values of observed (HO) and expected heterozygosities (HE) were 0.574 and 0.640, respectively, indicating a considerable amount of polymorphism within this collection. A genetic distance-based phylogeny grouped into two distinct groups, which were the landrace, moderate and weedy type, genetic distance (GD) value was 0.609. The physicochemical traits about crude oil contents and fatty acid compositions were analyzed using GC. Among tested germplasm, the total average oil contents (%) showed a range from 28.57 to 49.67 %. Five fatty acids and their contents in the crude oils are as follows: α-linolenic acid (41.12%-51.81%), linoleic acid (15.38%-16.43%), oleic acid (18.93%-27.28%), stearic acid (2.56%-4.01%), and palmitic acid (7.38%-10.77%). The average oil content of wild types was lower than landrace, and the oil content of middle genotype accessions was higher than other germplasm, but no significant variation between landrace and wild types was shown. Nevertheless, IT117174, landrace of Korea, was highest in crude oil content (47.11%) and linolenic acid composition (64.58%) among the used germplasm. These traits of the selected accessions will be helped for new functional plant breeding in perilla crop.
It is very crucial to evaluate the genetic diversity of peanut genetic resources for identification of peanut germplasm accessions and variety improvement. Cultivated peanut generally has two subspecies, hypogaea and fastigiata. In this study, we identified peanut into three plant types, virginia (var. hypogaea), spanish (var. vulgaris), and valencia (var. fastigiata). Former one belongs to ssp. hypogaea and latter two are involved in ssp. fastigiata. Twenty SSR markers were used to assess the genetic variation of three sets, hypogaea, vulgaris, and fastigiata, respectively. Out of variety-specific SSR primers tried in this study, ten pairs of SSR primers showed polymorphisms. Each accession could be identified by a specific set of polymorphic SSR primers, and allele number was evaluated among accessions, with an average of 6.7 in var. hypogaea and 5.4 in var. vulgaris and fastigiata. For evaluation of genetic diversity, gene diversity ranged from 0.336 to 0.844 and PIC (polymorphism information contents) ranged from 0.324 to 0.827 were investigated. Dendrograms based on genetic distances were constructed, which showed the existence of three different clusters. And these three different clusters might be associated with the genes involved in three plant types. The results also suggested that there were plentiful SSR polymorphisms among peanut germplasm accessions in RDA (Rural Development Administration, Korea) Genebank and SSRs might play an important role in evaluating peanut accessions and cultivar improvement.
TILLING (Targeting Induced local Lesions IN Genomes) is known to be an excellent methodology for reverse genetics approach. About 15,000 M3 TILLING lines have been developed after gamma-ray irradiation to the rice seeds of Donganbye. In order to assess genetic diversity of the TILLING population. we have employed a multiple dominant marker technique, such as AFLP. A total of 96 (0.64%) lines including Dongganbye were randomly selected and their genetic diversity was assessed on the basis of AFLP marker polymorphism by using 5 primer combinations. An average of 100.4 loci with a range of 97 to 106 were detected by using the primer combinations, resulting in 173 (34.6%) polymorphic loci among 96 lines. A broad range of similarities with 80% to 96% was evidenced between Donganbye and each of 96 TILLING lines, reflecting genetic diversity of the TILLING population. About 30 polymorphic loci have been cloned and their sequences have been blasted against rice whole genome sequences. The sequences evidenced highly significant matches to each of genes including exons and introns, upstream sequences and downstream of genes, and intergeneic sequences. Therefore, the TILLING rice population would be valuable genetic sources for rice functional genomics.
Assessment of the extent of genetic variability within a cultivated crop has important consequences in plant breeding and conservation of genetic resources. Random amplified polymorphic DNA (RAPD) markers were used to produce barley genomic DNA fingerprints. The aim of this work was to investigate the efficacy of polymorphism contained in such fingerprints on disclosing genetic relationships among 26 barley genotypes including advanced lines and released cultivars. Among the 21 primers the percentage of polymorphic bands ranged from 33% (OPG-07) to 83% (OPG-02), showing a high degree of molecular variation. The highest genetic similarity was observed between genotypes Karan-521 and Karan-741(58%), and the lowest genetic similarity was observed between the cultivars Lakhan and C 138 (3.7%). The similarity matrix by the UPGMA algorithm delineated the above genotypes into four major clusters. The results demonstrate the utility of RAPD markers in differentiating Indian barley varieties. KT and SJY were supported by 2008 National Agricultural Germplasm Management System Establishment Program.