Acyl-acyl carrier protein (ACP) thioesterase (TE) catalyze the hydrolysis of the thioester bond that links the acyl chain to the sulfhydryl group of the phosphopantetheine prosthetic group of ACP. This reaction terminates acyl chain elongation of fatty acid biosynthesis, and in plant seeds it is the biochemical determinant of the fatty acid compositions of storage lipids. A full-length cDNA of an acyl-ACP thioesterase, named CvFatB, was isolated from oil plant Cuphea viscosissima accumulating up to 90% caprylate (8:0) and caprate (10:0) in its seed oil. This cDNA contains a 1,245-bp open reading frame that encodes a protein of 415 amino acids. The deduced sequence also contains two essential residues (H317 and C352) for TE catalytic activity and a putative chloroplast transit peptide at the N-terminal. Overexpression of the CvFatB cDNA in Arabidopsis resulted in increased levels of saturated fatty acid, especially palmitate, and reduced levels of unsaturated fatty acids. The findings suggest that CvFatB from oil plant C. viscosissima can function as a saturated acyl-ACP TE and can potentially be used to diversify the fatty acid biosynthesis pathway to produce novel fatty acids.

The influences of ethylene inhibitors (AgNO3 and silver thiosulfate) and cytokinins (BAP and TDZ) on shoot regeneration from cotyledon and hypocotyl explants of B. napus cv. Youngsan were investigated. The presence of 50 μM Silver thiosulfate (STS) in shoot regeneration medium formed shoots at 60-68% after 3-4 weeks of culture, which was enhanced by 2-fold compared to that of Silver nitrate (AgNO3). Moreover, cotyledon explants were more regenerative than hypocotyls; shoots from cotyledon explants began to occur 4-5 days earlier than that of hypocotyl explants. TDZ at a concentration of 8-10 μM was effective for shoot regeneration, compared with BAP. Consequently, the optimal shoot regeneration response was observed in medium supplemented with 50 μM STS + 8 μM TDZ. In transmission electron microscopy (TEM) analysis, higher density of silver nanoparticles was shown to be accumulated widely inside the cell wall and plasmodesmata of regenerating leaf cultured in medium supplemented with AgNO3. By contrast, in the cell cultured in medium with STS, fine-grained deposits were partly observed in the surroundings of the cell wall.

The vascular system of plants consists of two conducting tissues, xylem and phloem, which differentiate from procambium cells. Xylem serves as a transporting system for water and signaling molecules and is formed by sequential developmental processes, including cell division/expansion, secondary cell wall deposition, vacuole collapse, and programmed cell death (PCD). PCD during xylem differentiation is accomplished by degradation of cytoplasmic constituents, and it is required for the formation of hollow vessels, known as tracheary elements (TEs). Our recent study revealed that the small GTPase RabG3b acts as a regulator of TE differentiation through its autophagic activation. By using an Arabidopsis in vitro cell culture system, we showed that autophagy is activated during TE differentiation. Overexpression of a constitutively active RabG3b (RabG3bCA) significantly enhances both autophagy and TE differentiation, which are consistently suppressed in transgenic plants overexpressing a dominant negative form (RabG3bDN) or RabG3bRNAi (RabG3bRNAi), a brassinosteroidinsensitive mutant bri1-301, and an autophagy mutant atg5-1. Wood (called secondary xylem) is the most abundant biomass produced by land plants including Populus and Eucalyptus, and therefore is considered to be one of the most cost-effective and renewable bioenergy resources. In an attempt to enhance xylem differentiation and thus to improve biomass traits in poplars, we generated transgenic poplars overexpressing the RabG3bCA form. As notable phenotypes, both stem height and diameter were increased and xylem area in vascular bundles was significantly expanded in RabG3bCA transgenic poplars compared to control plants. Taken together, these results demonstrate that RabG3b regulates xylem differentiation in both Arabidopsis and Populus. This study enhances our understanding of biological mechanisms underlying wood formation and serve as a framework to engineer the quality and quantity of wood as useful biomass.

Much effort has been expended to find agronomically important QTLs for improving soybean yield. However, the complexity of genome, such as genome duplication, limits the utility of genome-wide association studies and linkage analyses to identify genes controlling yield traits. We propose the variation block method, a three-step process for recombination block detection and comparison. The first step is to detect variations by comparing short-read DNA sequences of the cultivar to a reference genome of the target crop. Next, sequence blocks with variation patterns are examined and defined. The boundaries between the variation-containing sequence blocks are regarded as recombination sites. All the assumed recombination sites in the cultivar set are used to split the genomes, and the resulting sequence regions are named as variation blocks. The practicality of this approach was demonstrated by the identification of a putative locus determining soybean hilum color and known genes such as flower color gene. We suggest that the variation block method is an efficient genomics method for recombination block-level comparison of crop genomes. We expect that this method holds the prospect of developing crop genomics by bringing genomics technology to the field of crop breeding.

In rice, the stage of the meiosis in the pollen is sensitive stage resulted in the pollen sterility to reduce yield. Dianxi4 is a cold tolerant line. To monitoring the proteome expression patterns in the pollen of Dianxi4 under the cold stress, shotgun proteomic analysis was conducted to the anther of Dianxi4. The rice plant was grown in the peedy rice field then in the 10 DBH(days before heading), one individual rice plant was moved in the growth chamber under the condition of12℃/RH70%(12h day/12h night). Also the plant used as control was moved in the growth chamber unde the condition of 28℃/RH70%(12h day/12h night). after 4 days treatment, the plant were moved in a greenhouse. The treated rice anther were collected in the one day before heading. From the shotgun proteomic analysis, total of 3,855 non-redundant proteins were identified. Among them, 2,360 proteins were reproducibly identified through the treatment and replications. By the T-test, 1,181 differentially expressed proteins were detected. Through the GO analysis, proteins related in gene expression, cellular process, cellular biosynthetic process were enriched.

The goals of this research project are to identify the genes controlling plant architecture through the establishment of foundation for molecular breeding and to develop new rice varieties with useful characters associated with high yield leading to its commercialization. The research subjects of this project are as follows: improvement of plant architecture including tiller angle and number associated to harvest-index, construction of genetic and QTL map related to plant architecture and isolation of target genes, development of molecular markers with high efficiency, and further study for the mechanisms of recombination event and reproductive barrier occurring from cross between subspecies, development of new elite rice varieties with high yield and its commercialization. The isolated genes and products of this research project will be patented and molecular markers for those genes will be applied to breeding procedure. The breeding materials produced as outcomes will be provided to other breeders for further breeding programs. The developed varieties will be patented and registered to the national list of varieties, and will be distributed to our agricultural industries for the increase of its competitiveness and farmer’s income. The patents for genes, molecular markers, and varieties will be licensed out to uphold the agricultural biotechnology industries.

Perilla is a annual herb plant of the mint family, Laminaceae and mainly cultivated in eastern Asia, i.e. Korea, China and Japan. In response to an increased interest for healthy supplement food from the public, people are focusing on the properties of perilla. The applicable parts of perilla plants are the leaves and seeds. Perilla has been cultivated as a source of unsaturated fatty acid oil. But in spite of advantage of the important nutritional traits the genome or molecular studies on perilla remains largely unknown. Sequence comparisons of chloroplast (cp) genomes or nuclear ribosomal DNA (nrDNA) are of great important to provide a evidence for taxonomic studies or species identification or understanding mechanisms that underlie the evolution of perilla species. So, we tried to study a structural analysis of perilla genome and 45s nrDNA using 9 species (3 Diploid; Perilla B-17, P. hirtella, P. setoyensis / 6 Tetraploid; YCPL 285, YCPL 170, YCPL 205-1, YCPL 181-1, YCPL 177-1, YCPL 207-1). The complete cp genome and nrDNA of 9 perilla species were determined using Illumina sequencing technology and analyzed on the variance in base level between perilla B-17 and salvia miltiorrhiza. Total chloroplast genome size of perilla B-17 as a reference was 152,589 bp in length. We also identified an slightly overlapped intergenic regions between salvia miltiorrhiza and B-17. The results above will contribute to growing of molecular or genome structure and functional genomics of perilla available in studying perilla biology. For further study, we will look for genetic diversity of perilla species.

In the genus Chrysanthemum, repetitive DNA sequences, the dominant part of a genome, are still to be elucidated. To explore the matter, the present study applied fluorescent in situ hybridization (FISH) to the mitotic metaphase chromosome of Chrysanthemum boreale with C0t DNA as probes. Based on DNA re-assotiation kinetics, three kinds of C0t DNA exhibiting different degrees of repetitive nature were fractionated and used as FISH probes to map the repetitive sequences. Signals from all C0t DNAs were successfully observed but their coverage on the chromosomes was different among C0t-1, C0t-10, and C0t-100. C0t-1 FISH signals resulted to have its intensity on the telomeric region and were also dispersed on both chromosome arms except for some distal regions. In C0t-10, signals were observed in all parts of the chromosome with greater intensity around pericentromeric regions. FISH with C0t-100 DNA was observed in bright signals all over the chromosome. Signals of C0t FISH found in this study covered the regions where ribosomal DNAs and telomeric repeats of C. boreale have been distributed (previous report), thus signifying their repetitive attributes. The present results could enhance the efficiency of studying genomes, chromosomes and repetitive sequences of C. boreale and subsequently hasten the realization of the genetic scheme of Chrysanthemum.

Blueberry (Vaccinium spp.) is a member of the Ericaceae and eleven varieties have been registered at the Korea Seed & Variety Service for Plant Variety Protection (PVP). This study was to develop simple sequence repeat (SSR) markers next generation sequencing (NGS) analysis and to analysis genetic relationship of blueberry 31 varieties. Highbush blueberry ‘Camellia’ and rabbiteye blueberry ‘Alapaha’ varieties were used as sequencing materials. Out of total 987 SSR primers detected between ‘Camellia’ and ‘Alapaha’, 148 SSR primers were initially applied to select SSR markers for identification of blueberry varieties. Fourteen SSR markers showed polymorphism between 8 varieties. Seven SSR markers showed reproducibility and clear peak among 14 SSR markers. Genetic relationships of 31 blueberry varieties were analyzed and identified using 7 SSR markers. A total of 30 polymorphic SSR alleles were obtained and two to seven alleles were detected for each locus with an average of 4.3 alleles per locus. Average polymorphism information content was 0.556, ranging from 0.374 to 0.714. Genetic distance of clusters ranged from 0.38 to 0.93 by unweighted pair-group method with arithmetical average based on Jaccard’s distance coefficients. These newly developed SSR markers indicate usefulness for variety identification related to seed dispute and distinctness, uniformity and stability (DUS) test for blueberry.

Low temperature germinability (LTG) is an important trait for breeding of varieties for use in direct-seeding rice production systems. Although rice (Oryza sativa L.) is generally sensitive to low temperatures, genetic variation for LTG exists and several quantitative trait loci (QTLs) have been reported. The objective of this study was to develop and employ high-efficiency molecular markers for evaluation of LTG in rice germplasm. A panel of japonica rice accessions (n=180) from temperate regions in Asia was evaluated for LTG and genotyped with markers from regions previously reported to harbor other LTG QTLs. ANOVA revealed that four markers on chromosome 2, 4, and 11 from previously reported QTLs showed highly significant value (p < 1.0e-04) and their R2 ranged 0.083 (qLTG11-1) to 0.190 (qLTG4b-1). An association analysis was conducted using SNP data generated by sequencing of the panel. Eight SNP markers were found to be significantly associated with LTG using general and mixed linear models. Three SNP-based CAPS and dCAPS markers from these results were developed and showed higher accuracy in predicting sensitive LTG germplasm. These new LTG markers will be useful for molecular evaluation of germplasm, particularly to identify sensitive or weak LTG accessions.

The objective of the study was to identify 52 Asian pear accessions, two primary pear species, and one reference pear Asian pear with 12 microsatellite markers to maintain pear germplasm collection. The number of alleles of 12 microsatellites detected ranged from eight at CH03d12 to 18 at CH01f07. Gene diversity ranged from 0.7053 at CH01d08 to 0.9224 at CH01f07. The lowest value of PIC was 0.6600 at CH01d08 and the highest was 0.9171 at CH01f07. A group consisting of ‘Ooharabeni,’ ‘Bartlett,’ and P. calleryana was out-grouped and served as a reference to determine the relationship among Asian pear accessions. Except for the out-group, 50 Asian pears were segregated into two groups. Group I was divided in two small groups. Each small group was characterized by P. bretschneideri and P. ussuriensis, respectively. Group II was characterized as P. pyrifolia, and the group was divided in four small groups. The eigenvalue, difference, proportion, and cumulative of six principal components based on PCA to 12 microsatellite. The eigenvalue of the first principal components was 5.5850. The proportion of the first principal component was 0.9308. The cumulative value of the first two principal components was 0.9801. Consequently, nearly all of the results were elucidated by the two principal components. The results from analysis of the standard set of microsatellites in this study may be used as basic materials for the management of Asian pear germplasm collections, and the data might be useful in the development of a core collection.

Chrysanthemum (Chrysanthemum morifolium) is one of the most popular ornamental species in the world due to the great diversity of inflorescence form and color. There has been increasing demands for various types of chrysanthemums, such as cut flowers, potted plants and bedding plants. However, the genomic studies of this species have been not extensively conducted relative to other ornamental species due to high levels of polyploidy (2n = 4x =36 or 2n = 6x = 54) and heterozygosity as well as large genome size. In this work, we developed a molecular tool for cultivar identification using simple sequence repeats (SSRs) and investigated genetic diversity in 127 chrysanthemum cultivars. Of the 150 SSR primer pairs tested in this study, 62 primers were obtained from previous studies, while 88 primers were designed using the unigene sequences of C. nankingense and the Expressed Sequence Tag (EST) sequences of C. morifolium in the NCBI database. Thirty SSR primers were selected based on polymorphism and banding patterns in a subset of 8 cultivars and used to amplify the DNA of 127 chrysanthemum cultivars. The UPGMA dendrogram based on these 30 SSR markers showed that most of chrysanthemum cultivars were divided into five clusters. These results will benefit chrysanthemum research community to develop elite cultivars.

To understand the molecular mechanism of leaf morphogenesis in rice, ethylmethane sulfonate (EMS) treated Ilpoom mutant line with semi-narrow and adaxially rolled leaf phenotype was identified. The leaf rolling character is said to be more advantageous under high temperature and heat stress, and play as one of the defensive mechanisms. The F1 plants, generated from a cross of Ilpoom and mutant, showed normal phenotype. Genetic analysis of its F2 population suggested that the mutation was controlled by a single recessive gene with segregation ratio of 3:1. Using F2 mapping population derived from a cross of Ilpoom mutant and Milyang23, each chromosomes were screened with STS markers by the bulked segregant analysis (BSA) method. The candidate region was detected to a long arm of chromosome 1 near the centromeric region. Fine mapping of the locus is currently conducted. Moreover, other morphological characterizations of the mutant plants were identified. Cytological analysis of the leaf suggested that deformation of the bulliform cells led to the smaller size and less number of the bulliform cells, and caused leaf rolling trait.

Platycodon grandiflorum is a perennial herbal plant belongs to Campanulaceae family. It has very important genetic value as a major plant in Asterids order. The major ingredients are platycosides, terpenoid saponins. In Korean industrial plants market, it was produced 5,633 tons in 2013, and the total amount of production was less than only five species, omija, ginger, raspberry, yam and deodeok. P. grandiflorum is called ‘Gilgyung’ and is used as a fresh vegetable and an ornamental plant. Nowadays, various components of P. grandiflorum were already published. But, genetic research is in the starting stage. In this study, 11 cultivars; 1. MariesⅡ, 2. Hakone double white, 3. Hakone double blue, 4. Fuji white, 5. Fuji pink, 6. Fuji blue, 7. Astra white, 8. Astra pink, 9. Astra blue, 10. Astrasemi double blue, 11. Jangback, were analyzed using 60 Operon Universal RAPD primers. The results were phylogenetically analyzed and related to the morphological characteristics of the cultivars.

The Asteraceae/Compositae family is one of the biggest families in flowering plants and has more than 23000 species including the economically important lettuce, sunflower, and chicory as well as the agronomic weeds. With its significance and the progress in sequencing technology, its species have been subjected to the genome sequencing project worldwide. Although chrysanthemum is an important plant in the floricultural industry, however, it has been less studied at the level of genomics, compared with other species in the Asteraceae. There were only several reports on comparative analysis of transcriptome for chrysanthemum. Actually, the genome of Chrysanthemum species is known to be gigantic and complex with diverse status ranging from diploid to decaploid. Since the cultivated and commercial chrysanthemum exhibits hexaploid genome, we decided to select the diploid species with smaller genome as a material for reference genome sequencing. Thus, we launched a genome sequencing project with C. boreale which was previously reported to be diploid by cytogenetic analysis. We constructed sequencing libraries with insert size 300bp and 500bp and sequenced them from the paired end in 100bp read length with Illumina’s HiSeq platform. After quality checking, we preprocessed raw reads by removing duplicated reads and trimming reads with low quality value. Kmer frequency analysis with the cleaned reads showed that the genome is heterozygous, highly repetitive and gigantic, ranging from 2.9Gb to 5.8Gb. The cleaned reads were further subjected to error correction and primary assembly with SOAPdenovo2. Here, we’ll report the result of Kmer frequency analysis and genome assembly.

Understanding how crops interact with their environments is increasingly important in breeding program, especially in light of highly anticipated climate changes. A total of 150 recombinant inbred lines (RILs) of F12 generation derived from Dasanbyeo (Indica) x TR22183 (Japonica) were evaluated at Suwon 2010, Shanghai 2010, IRRI 2010 wet season, Suwon 2011, Shanghai 2011, IRRI 2011 dry season, and IRRI 2011 wet season as a total of seven diverse environments. Traits evaluation included eight important agronomical traits such as days to heading (DTH), culm length (CL), panicle length (PL), panicle number per plant (PN), spikelet number per panicle (SN), spikelet fertility (SF), 100-grain weight (GW), and grain yield (GY). As a result of genotyping using 384-plex GoldenGate oligo pool assay (OPA) set (RiceOPA3.1), the linkage map for 235 SNP markers covering a total of 926.53 cM with an average interval of 4.01 cM was constructed and a total of 44 main-effect quantitative trait loci (QTL)s and 35 QTLs by environment interaction (QEI) were detected for all eight traits using single environment and multi-environments analysis, respectively. Of these, fourteen putative QTLs for DTH, CL, PN, SN, GW and GY found in single environment analysis had the similar position to QEI for those traits, suggesting that these same QTLs from both single-and multi-environments are major and stable for certain traits. To the best of our knowledge, 12 QTLs consisted of four QTLs for CL (qCL2, qCL8.1, qCL8.2, and qCL8.3), six QTLs for GW (qGW3.1, qGW3.2, qGW7, qGW8, qGW10.1, and qGW10.2), one QTL for GY (qGY3) and one for SF (qSF4) out of 44 QTLs obtained from single environment analysis were considered to be novel since no overlapping QTL was reported from previous studies. In addition, 12 out of 35 QTLs obtained from multi-environments analysis were also novel.

Leaf mold disease in tomato (Solanum lycopersicum) is caused by Cladosporium fulvum, a fungal leaf pathogen. One of effective ways to control leaf mold is to breed disease-resistant tomato cultivars. Cf-4 and Cf-9 resistance (R) genes encode proteins that carry a leucine rich repeat domain and are located in plasma membrane. They trigger hypersensitive response following recognition of corresponding Avr4 and Avr9 proteins of C. fulvum, respectively. Cf-4 and Cf-9 genes are originated from wild tomato species S. habrochaites and S. pimpinellifolium and have been introgressed into commercial tomato cultivars. These two highly homologous orthologs exist as a cluster with four highly homologous paralogs. Due to this reason, development of genetic markers to distinguish these two functional R genes from their orthologs and paralogs is difficult. In this study, we tried to develop single-nucleotide polymorphism (SNP) markers to select tomato cultivars carrying resistant Cf-9 genotype. The genomic sequences of resistant Cf-4 and Cf-9 alleles, susceptible cf-9 alleles, and their paralogs were obtained from the GenBank database, and two functional SNPs causing non-synonymous substitution were found among them. Based on two SNPs, the Cf-9_2-SNP-F/R primer set for high resolution melting (HRM) analysis was developed. HRM analysis with this primer set could successfully distinguish tomato cultivars carrying resistant Cf-9 allele among 30 commercial tomato cultivars, which were characterized with the gene-based marker. These indicate that the SNP marker developed in this study is useful to trace Cf-9 genotype efficiently in marker-assisted selection in tomato.

Molecular characterization of crops improved through biotechnology has traditionally been conducted using Southern blot analysis which has been used to determine T-DNA copy number, the presence or absence of backbone (sequence outside of the T-DNA) and to demonstrate generational stability of the T-DNA insert. The advancement of high-throughput DNA sequencing (HTS) technology allows efficient characterization of the transgene incorportated into the genome of the plant by rapidly sequencing the entire plant genome. By combining NGS (Next Generation Sequencing) technologies with bioinformatic methods that identify the T-DNA insert derived from the plasmid vector and genome-T-DNA junction sequences, it has been shown that conclusions equivalent to those of a Southern blot are readily obtained. NGS is done at sufficient coverage depth (>75x) across the entire genome. By mapping the sequence reads to the plasmid vector, and identifying the number of unique junctions, we can confirm insert number, copy number, absence of backbone, across multiple generations. With the widespread availability of NGS and steadily decreasing costs it is likely that academia and industry will fully transition to NGS-based molecular characterizations in the near future.

Proline has been shown to accumulate in plant under various type of stresses. In our previous study, changes in cold hardiness and proline content showed contrasting patterns during a constant deacclimation. This study was performed to investigate the proline accumulation and related gene expression in response to repeated deacclimation and reacclimation in peach cultivar ‘Daewol’. Proline content was analyzed using the ninhydrin method and related gene expressions were examined using quantitative real-time RT-PCR. Proline contents of ‘Daewol’ increased during the repeated deacclimation treatments. Interestingly, during the twice deacclimation, expressions of P5CS (Δ1-pyrroline-5-carboxylatesynthase) constantly decreased, whereas expressions of P5CR (Δ1-pyrroline-5-carboxylatereductase) increased. Expressions of OAT (ornithine-δ-aminotransferase) indicated up- and down- pattern in response to repeated deacclimation and reacclimation. Our results indicated that proline responds positively to higher temperature in the shoots of peach cultivar ‘Daewol’ and expressions of both P5CS and P5CR genes could show contrasting patterns during the deacclimation. Moreover, our results suggest that ornithine pathway could serve as an alternative pathway in proline synthesis process during deacclimation in peach.

Tomato spotted wilt virus (TSWV) causes one of the most destructive viral diseases that threaten tomato (Solanum lycopersicum) worldwide. So far, eight TSWV resistance genes, Sw1a, Sw1b, sw2, sw3, sw4, Sw-5b, Sw-6, and Sw-7 have been identified and Sw-5b has been incorporated into tomato for prevention of TSWV. The objectives of this research are first to discover single nucleotide polymorphisms (SNPs) in Sw-5 alleles and then to develop SNP markers to distinguish resistant genotypes against TSWV for marker-assisted breeding in tomato. First, DNA sequences of Sw-5b alleles from both resistant and susceptible cultivars amplified using known Sw-5 gene-based marker was analyzed. The single functional SNP (G→A) was detected as non-synonymous substitution because this SNP causes change of arginine (Arg599) to glutamine (Gln599). Next, the primer pair for high resolution melting analysis (HRM) was designed around this SNP. To determine accuracy of this SNP marker to distinguish resistant Sw-5b genotypes against TSWV, genotypes of 32 commercial tomato cultivars were checked. The newly developed SNP marker could select six cultivars carrying resistant Sw-5b genotype, which was 100% correlated with genotypes based on the gene-based marker. These results indicate that the SNP maker developed in this study could be useful for better tracking resistance to TSWV in tomato breeding.