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Phytosterols are important structural components of plant cells that affect membrane fluidity, permeability, and membrane-related metabolic regulation. These compounds, which are abundant in vegetable oils and corn kernel oil, are also beneficial for human health. Cultivation of corn (Zea mays L.) produces huge amounts of cobs as a by-product, but efforts to utilize cobs are still limited. Here, we investigated phytosterol, crude oil, and fatty acid contents in the kernels and cobs of four major corn cultivars in South Korea and explored the potential use of cobs as a source of phytosterols. Total phytosterol levels were two times higher in cobs (68.0–217.1 mg 100 g−1 DW) than in kernels (43.8–89.5 mg 100 g−1 DW) and were highest in the kernels and cobs of Sinhwangok at 60 days after pollination. We showed that not only kernels but also cobs can be a rich source of phytosterols. The results also revealed that the amount of phytosterol is depending on a genetic background as well as developmental stages suggesting further investigation would enhance the utilization of corn cobs as a phytosterol source.

Corn (Zea mays L.) provides a major source of calories for human consumption and therefore, the nutritional components of corn have a large impact on human health. For example, corn kernels contain antioxidants, such as polyphenols (including anthocyanins and other flavonoids) and carotenoids. Such compounds represent useful targets for biofortification breeding. In this study, we used 34 corn inbred lines from three different regions (East Asia, Southern Asia, and subtropical regions) and 11 F1 hybrids derived from the inbreds to investigate antioxidant activity in yellow corn. We compared different methods for measuring antioxidant activity to test their consistency and to determine whether color could be used as an indicator of antioxidant activity. We also measured carotenoid levels in yellow corn. No difference in antioxidant activity was detected between inbred corn lines from temperate vs. tropical regions. We determined that carotenoid is a major contributor to antioxidant activity in yellow corn and that kernel color, especially yellowness, could be used as an indicator of antioxidant activity in yellow corn. These findings lay the foundation for the biofortification of yellow corn by providing information about the correlations among kernel color, carotenoid contents, and antioxidant activity and by identifying an easy method to assess antioxidant activity in yellow corn.

Fusarium head blight (FHB) caused by Fusarium species is a major disease of wheat and barley around the world. FHB causes yield reductions and contamination of grains with trichothecene mycotoxins including; nivalenol (NIV), deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-ADON), and 15-acetylde-oxynivalenol (15-ADON). The objectives of this study were to identify strains of F. graminearum isolated in Korea from 2012-harvested wheat grain and to test the pathogenicity of these NIV- and DON-producing isolates. Three hundred and four samples of wheat grain, harvested in 2012 in Chungnam, Chungbuk, Gyeongnam, Jeonbuk, Jeonnam, and Gangwon provinces were collected. We recovered 44 isolates from the 304 samples, based on the PCR amplification of internal transcribed spacer (ITS) rRNA region and sequencing. Our findings indicate that F. asiaticum was the predominant (95% of all isolates) species in Korea. We recovered both F. asiaticum and F. graminearum from samples collected in Chungnam province. Of the 44 isolates recovered, 36 isolates had a NIV genotype while 8 isolates belonged to the DON genotype (3-ADON and 15-ADON). In order to characterize the pathogenicity of the strains collected, disease severity was assessed visually on various greenhouse-grown wheat cultivars inoculated using both NIV- and DON-producing isolates. Our results suggest that Korean F. graminearum isolates from wheat belong to F. asiaticum producing NIV, and both F. graminearum and F. asiaticum are not significantly different on virulence in wheat cultivars.

High temperature is one of major environmental stress. Heat tolerance managing is difficult through the phenotypic selection, so marker assistant selection (MAS) using molecular markers like as RAPD, SSR etc. was tried to select useful traits for heat tolerance. Fourteen SSR markers reported by previous research were selected for this research. We tried to evaluate 14 SSR markers for MAS using 31 useful wheat resources including 24 crossing line from Turkey, six Korean wheat cultivars and Chinese spring. The average of the number of alleles and PIC values in this study were 6.14 and 0.64, respectively. Two major clades and four sub clades were grouped by phylogenetic tree using UPGMA. Four Korean wheat cultivars were distinct from other Turkey resources in the phylogenetic dendrogram. From the results, we expected that these markers were able to adapt to screening wheat genotyping for heat tolerance.

Dept. Animal bio, Chanbuk National University, Jeonju, 561-756ABSTRACTThis study was undertaken to characterize feed value and silage quality according to storage period and film layers for whole-crop barley silage. The crude protein(CP) content increased in all silage during the storage periods compared to those before silage,this content slightly increased over the prolonged storage period but it was not significant(p>0.05). Depending on the film layers of silage, 6 layers were higher than 4 layers. The neutral detergent fiber(NDF) and acid detergent fiber(ADF) contents also increased in all silage during storage periods compared to those before silage(P

Seed shattering of wild plant species is thought to be an adaptive trait to facilitate seed dispersal. For rice breeding, seed shatter-ing is an important trait for improving breeding strategies, particularly when developing lines use interspecific hybrids and introgression of genes from wild species. We developed F₃:₄ recombinant inbred lines from an interspecific cross between Oryza sativa cv. Ilpoombyeo and Oryza rufipogon. In this study, we genetically analyzed known shat-tering-related loci using the F₃:₄ population of O. sativa/O. rufipogon. CACTA-AG190 was significantly associated with the shattering trait CACTA-TD according to bulked segregant analysis results, and was found in the qSH-1 region of chromosome 1. Fine genetic mapping of the flanking regions around qSH-1 based on CACTA-AG190 revealed multiple-sequence variations. The highest limit of detection based on quantitative trait locus analysis was observed between shaap-7715 and a 518-bp insertion site. Two other quantitative trait locus analyses of seed-shattering-related loci, qSH-4 and sh-h, were performed using simple sequence repeat and allele-pecific single nucleotide polymor-phism markers. Our results can be applied for rice-breeding research, such as marker-assisted selection between cultivated and wild rice.

Pre-harvest sprouting (PHS) of wheat reduces grain yield and has deleterious effects on wheat flour quality. PHS resistance is strongly associated with grain color and seed dormancy. Resistance to PHS is a priority of wheat breeding program. We have studied a population of 122 Doubled Haploid (DH) lines from the cross between two cultivars, 'Keumkang' and 'Olgeuru', in order to detect QTLs correlated with PHS resistance. PHS was evaluated using mist spray in the humid chamber (PHS-MS), and the germination index (GI) was determined for two years. The variety 'Keumkang' has white grains and higher percentage of PHS rate (30.2%), while 'Olgeuru' has red grains and lower PHS rate (2.8%). There was significant difference in grain color according to the GI. PHS-MS was positively correlated with GI (r = 0.732, P < 0.001). Two molecular markers, Xbarc12 and Xgwm3, were found correlated with PHS resistance and GI. These markers were mapped on chromosomes 3A and 3D with LOD scores of 4.95 and 4.02, respectively. Xbarc12 explained the highest amount of phenotypic variation (R 2 ) which is 11.99% in GI and 27.25% in PHS. Xgwm3 explained 9.10% of phenotypic variation in GI. The respective value of PHS-MS and GI in Korean wheat cultivars ranged from 1.37% to 86.75% and from 0.03 to 0.73. This study provides useful information for marker-assisted wheat breeding for PHS resistance improvement in Korea.

This study was carried out to characterize the color of noodle sheet made from Korean wheat cultivars, which were then evaluated on grain and flour properties, in order to enhance the breeding-line selection for noodle wheat. In particular, a rapid method was applied to investigate the effects of iron (Fe) contents on the lightness of noodle sheet for the selection of breeding-lines with high Fe contents. Wheat flour lightness of Korean wheat cultivars had a negative correlation with ash (r = -0.634, P

Inter simple sequence repeat (ISSR) is a technique that leads to the development of novel specific molecular markers and relationship analysis between species. In this study, 54 ISSRs were used to develop cultivar-specific DNA sequence characterized amplified regions (SCARs) for Korean wheat cultivars (Triticum aestivum). Using nine of 54 UBC ISSR primers, 16 cultivar-specific fragments were detected among 32 wheat cultivars. Of the 16 primers, 10 successfully amplified targets in 32 cultivars and six novel cultivar-specific markers were finally selected. A total of 13 Korean wheat cultivars (Ol, Dahong, Namhae, Jinpum, Anbaek, Jopoom, Jokyung, Sinmichal 1, Jeokjoong, Dajung, Goso and Joah) were classified by newly developed six SCAR markers. Cultivar-specific markers can be used not only for cultivar fingerprinting but also for marker-assisted selection in wheat breeding program.

Species of the genus Lilium are well known for their large genomes. Although expansion of noncoding repeated DNA is believed to account for this genome size, retroelement del Ty3-gypsy is the only one described so far in the genus Lilium. We isolated Ty1-copia elements from Lilium longiflorum and named them LIREs (lily retrotransposons). The long terminal repeats, primer binding site, and polypurine tract sequences are highly similar among the LIRE elements, indicating that they are in the same lineage. Although the protein-coding regions were highly decayed, the sequence motifs of the integrase, reverse transcriptase, and RNase H domains were identifiable as belonging to the order of Ty1-copia elements. Phylogenetic analysis and primer binding site sequences revealed that these elements belonged to the Ale lineage among the six lineages of plant Ty1-copia elements. Base substitutions in the long terminal repeats estimated that the integration times of the LIRE Ty1-copia elements were between 0.7 and 5.5 mya. In situ hybridization showed that the LIRE elements were present in all the chromosomes of L. longiflorum and L. lancifolium, but absent in centromeres, telomeres, and 45S rRNA sites in both species. The LIRE elements were present very abundantly in species of the genus Lilium, but absent in other genera of the family Liliaceae, implying that the LIRE elements might have contributed to the expansion of the genome in the genus Lilium.

Pong elements are active class 2 transposons in rice. We found Pong-like elements in Arabidopsis thaliana and named them as AtPong (Arabidopsis thaliana Pong) elements. The AtPong elements carried 13 bp of TIRs and two ORFs in which NAM DNA binding domain and DDE catalytic domain are encoded. Ping and mPing (miniature Ping) elements are deficient Pong elements and we found AtPong derived deficient AtPing and AtmPing elements. We also found a homologous element of the AtPong element in Brassica rapa. This element was a deficient element by internal deletion, but showed high sequence similarity with the AtmPing so that it was named as BrmPing (Brassica rapa miniature Ping). The AtPong, AtPing, and AtmPing elements were present in intergenic regions except one element, AtPing1, which was present in an exon of a F-box protein gene. Among the different A. thaliana ecotypes, the AtPing1 showed polymorphisms of present and absent in the F-box protein gene. The excision of the AtPing1 restored the expression of the F-box protein gene, indicating that the expression of the F-box protein genes is regulated by the AtPing1.

The genus Allium includes several important condiment and ornamental vegetable species. The botanical status of many more than 600 species in the genus Allium has not been clearly classified. We used inter simple sequence repeat (ISSR) technique to analyze the phylogenetic relationships among 24 individual accessions and species that represent cultivated Allium species and their ancestral species. Nucleotide sequence analysis was used to rule out homoplasy, the possibility that unrelated ISSR-bands migrated to the same positions during gel electrophoresis. To avoid spurious results, PCR reactions were conducted in duplicate on independent thermocyclers and only reproducible bands were used for analysis. We detected 153 polymorphic bands from 20 ISSR primers. The ISSR polymorphism profiles were used to group most of the Allium species and accessions according to previous classification. However, A. chinense, previously included in the Rhizirideum section, was distinct from other species in the phylogenetic dendrogram. A. wakegi, the Korean endemic ‘Jjokpa’ and hybrid between A. cepa and A. fistulosum, was grouped in the Cepa section. A. monanthum, another Korean endemic ‘Dalae,’ was grouped in the Rhizirideum section. Because phylogenetic analysis of these three Korean endemic species has not been reported previously, the current report may allow these species to be included in future phylogenetic studies.

Cold stress discourages development of the full genetic potential of plants and results in serious adverse effects on plant growth and limits agricultural productivity. Garlic (Allium sativum) requires low temperatures for the induction of flowering and bulb development. However, low or freezing temperatures can often cause physiological damage. Cold-responsive genes were isolated from a Korean garlic variety through systematic analyses using differential display (DD)-PCR, reverse transcription (RT)-PCR, and quantitative (Q)-PCR. Of the 2470 transcripts observed, 76 transcripts were up-regulated and 20 transcripts were down-regulated in response to cold temperatures (4°C) as determined by DD-PCR analysis. The differentially-expressed genes were further narrowed to 15 up-regulated and four down-regulated genes through subsequent RT-PCR and Q-PCR analyses. Of the 15 up-regulated genes, 11 genes were homologous to previously-reported abiotic-stress regulated genes in other species, and four genes did not match any known genes. Of the four down-regulated genes, three genes matched function-annotated genes and one gene did not match any genein the BLAST analysis. While most of the up-regulated poly-peptides were hydrophilic, the down-regulated polypeptides were neutral or hydrophobic. Of the 19 differentially-regulated genes, four genes showed different expression profiles in different tissues upon cold stress. Genetic manipulation of the CR genes obtained may provide molecular tool for overcoming frost damage of the garlic plants during hibernation.

Although lily is the second largest flower crop in cutting flower commodity, only six simple sequence repeats SSRs have been reported. Thus, we developed expressed sequence tag derived-SSRs (EST-SSRs) for the Lilium genus. Among 2,235 unique ESTs, 754 ESTs contained SSR motifs, among which 165 ESTs were amenable to primer design. Among these 165 EST-SSRs, 131 EST-SSRs showed amplification in at least one Lilium species, and 76 EST-SSRs showed amplification in at least nine species. Of the 76 EST-SSRs, 47 showed amplification in all Lilium species analyzed. Using 10 breeding lines, we selected 21 EST-SSRs that had the highest number of alleles and polymorphism information content. The polymorphism information content values of these selected EST-SSRs ranged from 0.49 to 0.94 with an average of 0.76, which are higher than other plant species. The phylogenetic dendrogram derived from the amplification profiles of the 21 high polymorphic EST-SSRs was congruent with the genetic background of the 84 selected lily accessions and hybrids, which are available in commerce. Thus, the developed EST-SSRs will be very useful in germplasm management, genetic diversity analysis, cultivar finger printing, and molecular breeding in the lily.

The gene structure and sequence diversity of 5S rRNA genes were analyzed in 13 Allium species. While the lengths and sequences of the coding gene segments were conserved, the spacers were highly variable and could be characterized as either short (213–404 bp) or long (384–486 bp) spacers. The short spacers were further classified into five subtypes (SS-I to SS-V) and the long spacers into four subtypes (LS-I to LS-IV). The short spacers were more conserved than were the long spacers. There was a sequence duplication of 85 bp in SS-III that distinguished it from SS-II. The coding sequences of the 5S rRNA genes started with CGG and ended with either CCC or TCC. Both long and short spacers started with TTTT at their 5′-ends. However, the long spacers ended with a 3′-TGA sequence, whereas the short spacers terminated with various sequences, such as TTA, ATA, or TGA. GC content ranged from 27 to 41% in whole repeats, and the GC content in the long spacers was lower than in the short spacers. The nucleotide diversity in the coding regions was lower than in the spacers, and the nucleotide diversity in the coding regions did not correlate with that of the spacers. FISH analysis confirmed that each Allium species has either short spacers or long spacers. Although chromosomal locations of the 5S rRNA genes in Allium wakegi confirmed the allodiploid nature of A. cepa and A. fistulosum, spacer sequences revealed the absence of SS-II in A. cepa and in A. wakegi. The current study demonstrated that the 5S rRNA genes diverged in early stages in Allium species differentiation except of the allodiploid A. wakegi.

Understanding species evolution and improvement requires information of their genome origin and differentiation. Among the species in the family Gramineae, genome identities of Agropyron-Elytrigia-Leymus group are still ambiguous. In order to delineate the genome relationship, nucleotide sequence analysis in the rDNA ITS regions was carried out among the species in the genera Elytrigia, Agropyron, Psathyrostachys, Leymus, and Psacopyrum containing E, St, P, Ns, and Xm genomes. The ITS-1 and ITS-2 showed a narrow range of variation in length except for the presence of a pentanucleotide, TGGGG, in/del in some haplotypes, whereas higher numbers of nucleotide substitutions were observed in most genera. There were 187 variable sites in the ITS-1, 5.8S, and ITS-2 regions, in which a few genome specific mutations were observed. While the level of variation was similar between ITS-1 and ITS-2, the rate of transition mutation versus transversion mutations was different among the ITS-1, 5.8S, and ITS-2 segments. GC contents of the ITS regions ranged between 55–65% between genomes and the haplotypes of P and H genomes were slightly higher than others. In phylogenetic analysis, the ITS haplotypes were classified into two groups; one containing H, Ns, NsXm genomes, and another containing P, St, and E genomes, which are congruous to the genome affinities from other studies. Among the four genomes in Pascopyrum smithii (2n=8x=56, StStNsNsHHXmXm), the haplotypes of H and St genomes were identified with the reference diploid species, but the haplotypes having Ns and Xm genomes were not found in the present analysis.

MUG1 is a MULE transposon-related domesticated gene in plants. We assessed the sequence diversity, neutrality, expression, and phylogenetics of the MUG1 gene among Oryza ssp. We found MUG1 expression in all tissues analyzed, with different levels in O. sativa. There were 408 variation sites in the 3886 bp of MUG1 locus. The nucleotide diversity of the MUG1 was higher than functionally known genes in rice. The nucleotide diversity (pi) in the domains was lower than the average nucleotide diversity in whole coding region. The pi values in nonsynonymous sites were lower than those of synonymous sites. Tajima D and Fu and Li D* values were mostly negative values, suggesting purifying selection in MUG1 sequences of Oryza ssp. Genome-specific variation and phylogenetic analyses show a general grouping of MUG1 sequences congruent with Oryza ssp. biogeography; however, our MUG1 phylogenetic results, in combination with separate B and D genome studies, might suggest an early divergence of the Oryza ssp. by continental drift of Gondwanaland. O. longistaminata MUG1 divergence from other AA diploids suggests that it might not be a direct ancestor of the African rice species.

A distinct feature of eukaryotic genomes is the presence of gene families. The polygalacturonase (PG) (EC3.2.1.15) gene family is one of the largest gene families in plants. PG is a pectin-digesting enzyme with a glycoside hydrolase 28 domain. It is involved in numerous plant developmental processes. The evolutionary processes accounting for the functional divergence and the specialized functions of PGs in land plants are unclear. Here, phylogenetic and gene structure analysis of PG genes in algae and land plants revealed that land plant PG genes resulted from differential intron gain and loss, with the latter event predominating. PG genes in land plants contained 15 homologous intron blocks and 13 novel intron blocks. Intron position and phase were not conserved between PGs of algae and land plants but conserved among PG genes of land plants from moss to vascular plants, indicating that the current introns in the PGs in land plants appeared after the split between unicellular algae and multicelluar land plants. These findings demonstrate that the functional divergence and differentiation of PGs in land plants is attributable to intronic loss. Moreover, they underscore the importance of intron gain and loss in genomic adaptation to selective pressure.

Allium is a very diverse genus with over 600 species distributed worldwide. Haplotype analyses of 45S rRNA ITS, trnH-psbA spacer, and matK gene sequences in 9 Allium species were carried out, subsequent to which phylogenetic relations of the nine species were also analyzed. Of the three genes, the nuclear 45S rRNA ITS sequences showed the highest variation with one haplotype in each species. The other two chloroplast genes revealed that more than one haplotype was present in each species, and each haplotype was present in several of the species. In the matK gene, EcoRI restriction revealed heteroplasmy in which the functional gene retains the EcoRI recognition site while the nonfunctional, pseudogene does not. Phylogenetic patterns were not consistent among the haplotypes of the 45 rRNA ITS, trnH-psbA spacer, and matK genic regions. This phylogenetic incongruency might be due to the presence of multiple haplotypes in each of the chloroplast genes. However, the inconsistency of the phylogenetic relationships, based on the 45S rRNA ITS sequences makes a strong case for further analysis.