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        41.
        2009.08 구독 인증기관·개인회원 무료
        Whipgrass [Hemarthriacompressa(Linn.f.)R.Br.] has several outstanding characteristics that make it attractive in livestock production systems. These include superior cool-season growth compared to other C₄ grasses, persistence under grazing on poorly drained soils, and relatively high herbage digestibility that declines at a slower rate with increasing maturity than for most C₄ grasses. More than 50 years hard work, a whipgrass breeding group in Sichuan Agricultural University (SAU) collected 84 accessions from south china. Through germplasm evaluation and breeding, 3 varieties, Chong gao, Guang yi and Ya an, were released by the end of 2009. All of them are very popular in south china from 1986. In the future, the team approach emphasizes plant improvement in seedling vigor and establishment, seed production, cold tolerance, photoperiod response, seasonal distribution of forage production, forage quality, insect and disease resistance.
        42.
        2009.08 구독 인증기관·개인회원 무료
        In this paper, by investigating soil, field vegetation, and surface wind erosion status, combining in2 door analysis, the effect of vegetation recovery on sandy degraded grassland in Yanchi is studied. The results show t㏊t : after the process of protective growth, grazing rest and reseeding, the plant species and vegetation coverage are increased, and biomasses are enhanced about 66. 3214, at the same time, the effect of the measure of combining protective growth, grazing rest and reseeding is better t㏊n t㏊t of single protective growth and grazing rest, the formers biomass is 1. 54 times more t㏊n the latter. With the fixing of drifting - sand and the recovering of vegetation in demonstration area, the content s of physical clay minerals, organic matter, total N, available P and available K are all increased compared with those on drifting - sand. The thickness of wind erosion in drifting - sand control area is reduced, and the thickness is different in different vegetation recovering area, in which Artemisia sphaerocephala planting area suffers slight wind erosion; Caragana korshinskii forest present s slightly accumulating status, the accumulating thickness in Tamarix and Salix psammophila forest is the most.
        43.
        2009.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this work, effects of carbon matrix on sliding friction and wear behavior of four kinds of C/C have been investigated against 40 Cr steel ring mate. Composite A with rough lamination carbon matrix (RL) shows the highest volume loss and coefficient of friction, while composite D with smooth lamination/resin carbon matrix (SL/RC) shows the lowest volume loss. The worn surface of composite A appears smooth, whereas that of composite C with smooth lamination carbon (SL) appears rough. The worn surface of composite D appears smooth under low load but rough under high load. Atomic force microscope images show that the size of wear particles on the worn surface is also dependent on the carbon matrix.
        3,000원
        44.
        2008.09 구독 인증기관 무료, 개인회원 유료
        Somatic cells such as oviduct epithelial cell, uterine epithelial cell, cumulus-granulosa cell and buffalo rat river cell has been used to establish an effective culture system for bovine embryos produced in in vitro. But nitric oxide (NO) metabolites secreted from somatic cells were largely arrested the development of bovine in vitro matured/ in vitro fertilized (IVM/IVF) embryos, suggesting that NO was induced the embryonic toxic substance into culture medium. The objective of this study was to investigate whether BOEC co-culture system can ameliorate the NO-mediated oxidative stress in the culture of bovine IVM/IVF embryos. Therefore, we evaluated the developmental rate of bovine IVM/IVF embryos under BOEC co-culture system in the presence or absence of sodium nitroprusside (SNP), as a NO donor, and also detected the expression of growth factor (TGF-p , EGF and IGFBP) and apoptosis (Caspase-3, Bax and Bcl-2) genes. The supplement of SNP over 5 uM was strongly inhibited blastocyst development of bovine IVM/IVF embryos than in control and 1 uM SNP group (Table 2). The developmental rates beyond morulae stages of bovine IVM/IVF embryos co-cultured with BOEC regardless of SNP supplement (40.4% in 5 uM SNP+ BOEC group and 65.1% in BOEC group) were significantly increased than those of control (35.0%) and SNP single treatment group (23.3%, p<0.05: Table 3). The transcripts of Bax and Caspase-3 genes were detected in all experiment groups (1:Isolated fresh cell (IFC), 2:Primary culture cell (PCC), 3:PCC after using the embryo culture, 4: PCC containing 5 uM SNP and 5: PCC containing 5 uM SNP after using the embryo culture), but Bcl-2 gene was not detected in IFC and PCC (Fig. 1). In the expression of growth factor genes, TGF-p gene was found in all experimental groups, and EGF and IGFBP genes were not found in IFC and PCC (Fig. 2). These results indicate that BOEC co-culture system can increase the development beyond morula stages of bovine IVM/IVF embryos, possibly suggesting the alleviation of embryonic toxic substance like nitric oxide.
        4,000원
        45.
        2006.06 KCI 등재 구독 인증기관·개인회원 무료
        The yields of the n-hexane-soluble, ethyl acetate-soluble, methanol-soluble and methanol-insoluble fractions from the powdered water extracts were 8.2%, 10.6%, 32.0% and 49.2%, respectively (Table 1). The antifungal activities of water extracts, n-hexane-soluble fraction, ethyl acetate-soluble fraction, methanol-soluble fraction and methanol-insoluble fraction against L. edodes were 23.5%, 26.2%, 41.5%, 25.4% and 2.5%, respectively, at 1000ppm (Figure3). The ethyl acetate-soluble fraction showed much higher antifungal activity than the other fractions. The antifungal activity of the ethyl acetate-soluble fraction against L. edodes at 1000 ppm showed a statistically significant difference in the fractions of n-hexane-soluble, ethyl acetate-soluble, methanol-soluble and methanol-insolub
        46.
        2006.06 KCI 등재 구독 인증기관·개인회원 무료
        The yields of the fractions of n-hexane-soluble, ethyl acetate-soluble and methanol-soluble from the P. densiflora sawdust were obtained 1.36%, 2.21% and 4.03% using organic solvents, respectively (Table 1). The antifungal activity of the n-hexane extracts against L. edodes at concentrations 125, 250, 500, 750 and 1000 ppm were 36.5%, 41.2%, 43.1%, 45.4% and 47.6%, respectively (Table 2). The percent of antifungal activity against L. edodes was the greatest for the n-hexane extracts, ranging from 36.5% to 47.6% at a concentrations of 125 ppm to 1000ppm, with the values for all concentrations significantly different from one another. In this experiment, the antifungal activity by the n-hexane extracts was the highest. This result supposed that the n-hexane extracts have not only many more inhibitory compounds against L. edodes than the ethyl acetate and methanol extracts but also the inhibitory compound may be more easily dissolved by n-hexane than by ethyl acetate or methanol.
        50.
        2003.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        7,000원
        52.
        2020.12 KCI 등재 서비스 종료(열람 제한)
        Cordyceps has been used in traditional Chinese medicine more than 2000 year ago. In this study, the new Cordyceps militaris was founded and isolated from O-dae mountain in Korea, and was identified its genetic characteristics. The newly isolation strain HB8 was most closet to Cordyceps militaris W141449 (99.82%), Cordyceps militaris JLCY-LI819 (99.82%) and Cordyceps militaris 4642 (99.81%), respectively. the genotypic result was show that train HB8 was belonging to the Cordyceps militaris genus, therefore, Cordycep militaris HB8 proposed with accession number MT835161. This study we find the optimal condition for production of cordycepin from Cordyceps militaris HB8 was 8 ㎎ /g (200 g of pupa, 1 g of KH2PO4, 0.5 g of K2HPO4, 20 g of glucose, 1 g of MgSO4, 0.05 g of vitamin B1, and 1 ㎎ of NAA per liter; light condition 300-700 Lux and day/night was 14 h/10 h) and the optimum condition for the production of adenosine was 2.6 ㎎/g (15 g of skim milk powder, 1 g of KH2PO4, 0.5 g of K2HPO4, 20 g of glucose, 1 g of MgSO4, 0.05 g of vitamin B1, and 1 ㎎ of NAA per liter; light condition 300-700 Lux and day/night was 14 h/10 h).
        53.
        2015.07 서비스 종료(열람 제한)
        The β-carotene biofortified transgenic soybean was developed recently through Agrobacterium -mediated transformation using the recombinant PAC (Phytoene synthase-2A-Carotene desaturase) gene in Korean soybean (Glycine max L. cv. Kwangan). GM crops prior to use as food or release into the environment required risk assessments to environment and human health in Korea. Generally, transgenic plants containing a copy of T-DNA were used for stable expression of desirable trait gene in risk assessments. Also, information about integration site of T-DNA can be used to test the hypothesis that the inserted DNA does not trigger production of unintended transgenic proteins, or disrupt plant genes, which may cause the transgenic crop to be harmful. As these reasons, we selected four transgenic soybean lines expressing carotenoid biosynthesis genes with a copy of T-DNA by using Southern blot analysis, and analyzed the integration sites of their T-DNA by using flanking sequence analysis. The results showed that, T-DNA of three transgenic soybean lines (7-1-1-1, 9-1-2, 10-10-1) was inserted within intergenic region of the soybean chromosome, while T-DNA of a transgenic soybean line (10-19-1) located exon region of chromosome 13. This data of integration site and flanking sequences is useful for the biosafety assessment and for the identification of the β-carotene biofortified transgenic soybean.
        54.
        2015.07 서비스 종료(열람 제한)
        A variety of genetically modified (GM) crops have been developed in Korea. In these crops, the resveratrol-enriched transgenic rice plant has moved ahead to generate the dossier for regulatory review process required for commercialization of GM crop. The resveratrol-enriched transgenic rice plant could be released to farmers for cultivation after national regulators have determined that it is safe for the environment and human health. Here we developed a PCR-based DNA marker based on flanking sequences of transgene for the discrimination of zygosity in resveratrol-enriched transgenic rice plant. This DNA marker will be useful for identifying of resveratrol-enriched transgenic rice plant, and can also be use to estimate transgene movement occurred by pollen transfer or seed distribution.
        55.
        2015.07 서비스 종료(열람 제한)
        Clubroot is a devastating disease caused by Plasmodiophora brassicae and results in severe losses of yield and quality in Brassica crops including Brassica oleracea. Therefore, it is important to identify resistance gene for CR disease and apply it to breeding of Brassica crops. In this study, we applied genotyping-by-sequencing (GBS) technique to construct high resolution genetic map and mapping of clubroot resistance (CR) genes. A total of 18,187 GBS markers were identified between two parent lines resistant and susceptible to the disease, of which 4,103 markers were genotyped in all 78 F2 plants generated from crossing of both parent lines. The markers were clustered into nine linkage groups spanning 879.9 cM, generating high resolution genetic map enough to refine reported reference genome of cabbage. In addition, through QTL analysis using 78 F2:3 progenies and mapping based on the genetic map, two and single major QTLs were identified for resistance of race 2 and race 9 of P. brassicae, respectively. These QTLs did not show collinearity with CR loci found in Chinese cabbage (Brassica rapa) but roughly overlapped with CR loci identified in cabbage for resistance to race 4. Taken together, genetic map and QTLs obtained in this study will provide valuable information to improve reference genome and clubroot resistance in cabbage.
        56.
        2014.07 서비스 종료(열람 제한)
        Mungbean (Vigna radiata) is a fast-growing, warm-season legume crop that is primarily cultivated in developing countries of Asia. We constructed a draft genome sequence of mungbean to facilitate genome research into the subgenus Ceratotropis and to enable a better understanding of the evolution of leguminous species. The draft genome sequence covers 80% of the estimated genome, of which 50.1% consists of repetitive sequences. In total, 22,427 high confidence protein-coding genes were predicted. Based on the de novo assembly of additional wild mungbean species, the divergence of what was eventually domesticated and the sampled wild mungbean species appears to have predated domestication. Moreover, the de novo assembly of a tetraploid Vigna species (Vigna reflexo-pilosa var. glabra) provided genomic evidence of a recent allopolyploid event. To further study speciation, we compared de novo RNA-seq assemblies of 22 accessions of 18 Vigna species and protein sets of Glycine max and Cajanus cajan. The species tree was constructed by a Bayesian Markov chain Monte Carlo method using highly confident orthologs shared by all 24 accessions. The present assembly of V. radiata var. radiata will facilitate genome research and accelerate molecular breeding of the subgenus Ceratotropis.
        57.
        2014.07 서비스 종료(열람 제한)
        Resveratrol rice Iksan526 was developed by overexpession of T-DNA (RB::P-Ubi::RS::T-NOS::P-35S::PAT::T-35S::LB) in rice variety Dongjin. To confirm one locus insertion of T-DNAs, Mendelian genetic analysis was carried out on selection marker bar gene and objective RS gene separately by using a F2 population derived from a cross of Dongjin/Iksan526 (T6). A total of 450 four-leaf-old plants from F2 population were treated by 0.3% basta, and a phenotypic separation ratio of 3:1 (321 survival: 129 dead, p>0.90) complied with Mendelian inheritance indicating one locus insertion of bar gene. Genotypic separation was analyzed by using PCR with specific primers for 300 plants, which were selected from 321 survival plants after phenotypic separation. Results revealed a ratio 1:2 of homologous to heterozygous (92:208, p>0.90), which further confirmed one locus insertion of RS gene. In addition, comparison on agronomic traits and resveratrol contents between transgenic rice and the donor variety were launched to evaluate the phenotypic performance over multi-generations (years).
        58.
        2012.07 서비스 종료(열람 제한)
        The C-repeat/dehydration-responsive element binding transcription factors (CBF/DREBs) are involved in an important pathway for abiotic stress-response in plants. We have identified CBF/DREB1 gene family from Brassica rapa whole genome sequence and designated them as BrDREB1s. They contain conserved nucleus localization signal, AP2/EREBP domain, and CBF/DREB1 signature, as other known plant CBF/DREB1s. By comparative genomics, we found that nine of ten BrDREB1 genes were present in seven macro-synteny blocks co-linear to four Arabidopsis counterpart blocks and also genomic organizations of their flanking regions were very similar to those for co-linear Arabidopsis CBF/DREB1 genes. In particular, three genes, BrDREB1A, BrDREB1B1, and BrDREB1C1, were closely located within a 59 kb genomic sequence, which was similar to that of their Arabidopsis counterpart genes. However, the genomic regions of those BrDREB1 genes contained additional sequences, compared to their co-linear regions in A. thaliana. The expression of BrDREB1 genes under abiotic stresses were examined by searching microarray database and by RT-PCR analysis. All of eight genes tested were highly up-regulated during cold treatment and some of them were also responsive to salt, drought, and ABA treatment. Taken together, these results indicate that CBF/DREB1-mediated stress signaling pathway is also functioning in B. rapa. On the other hand, differences in genomic organization and gene number for CBF/DREB1 are thought to cause different response to stress between B. rapa and A. thaliana. In this presentation, we will introduce more detailed results for CBF/DREB1 gene family in B. rapa.
        59.
        2012.07 서비스 종료(열람 제한)
        Miniature inverted- repeat transposable elements are expected to play vital role in evolution of genes and genome of major eukaryotic organisms. However, there have been little reports on MITEs in B. rapa, a polyploidy model genome. We identified 13 novel MITE families in B. rapa genome by computational approach. Out of 13 MITEs families three, eight and two were classified under stowaway-like, tourist-like and hAT super families based on their unique structural characteristics. We characterized the members of 13 MITE families from the available 256 Mbp from whole genome draft sequences of B. rapa. We found ech MITE has high copiy number ranges from 14 to 977 which are distributed randomly along all the chromosomes. We also found more than 40% of the MITE members were associated with genes and gene rich regions. Furthermore, the polymorphism due to insertion and non-insertion of MITEs analysis suggest that MITEs are active in the genome. As, such the newly identified MITEs will provide a foundation for the further analysis of roles of MITEs in gene and genome evolution.
        60.
        2011.12 KCI 등재 서비스 종료(열람 제한)
        Ginseng (Panax ginseng) is frequently used in Asian countries as a traditional medicine. The major components of ginseng are ginsenosides. Among these, ginsenoside compound K has been reported to prevent the formation of malignancy and metastasis of cancer by blocking the formation of tumor and suppressing the invasion of cancer cells. In this study, ginsenoside Rb1 was converted into compound K, via secreted β-glucosidase enzyme from the Leuconostoc lactis DC201 isolated, which was extracted from Kimchi. The strain DC201 was suspended and cultured in MRS broth at 37℃. Subsequently, the residue from the cultured broth supernatant was precipitated with EtOH and then dissolved in 20 mM sodium phosphate buffer (pH 6.0) to obtain an enzyme liquid. Meanwhile, the crude enzyme solution was mixed with ginsenoside Rb1 at a ratio of 1:4 (v/v).The reaction was carried out at 30℃ and 190 rpm for 72 hours, and then analyzed by TLC and HPLC. The result showed that ginsenoside Rb1 was transformed into compound K after 72 hours post reaction.
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