• Journal of Agricultural Extension & Community Development
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• v.21 no.2
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• pp.143-184
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• 2014

The purpose of this study is to explore the present and future agricultural extension system and international cooperation systems for agricultural technologies in Ghana. The role of agricultural extension in the next decade should be quite different from what it was 10 years ago or even now. Its role as a facilitator of agricultural knowledge system would only increase as more participants from private sector would get involved in extension. The public sector extension would still continue to be the major extension provider in most parts of the country as the private sector alone would not be able to meet even partially the varied needs of farmers. Internal reforms are thus going to be the greatest challenge for the Ghana Extension System. The cooperation systems work in partnership with other stakeholder to provide agricultural extension and advisory services to farmers. Innovations (information/knowledge) emerging from the seed industry may be seen as dynamic and systemic process which can emerge from many sources. KAFECI's interventions must be flexible to accommodate such changes if the need arises in subsequent years (year 2 & 3). The framework and tools for technology transfer and dissemination is developed on "innovation platform" where a group of stakeholders/collaborators with diverse social and economic backgrounds, work towards a common objective or challenge.

• The Plant Pathology Journal
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• v.34 no.1
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• pp.71-77
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• 2018

Resistance to Tomato spotted wilt virus isolated from paprika (TSWV-Pap) was overcome at high temperatures ($30{\pm}2^{\circ}C$) in both accessions of Capsicum annuum S3669 (Hana Seed Company) and C. chinense PI15225 (AVRDC Vegetable Genetic Resources). S3669 and PI15225, which carrying the Tsw gene, were mechanically inoculated with TSWV-Pap, and then maintained in growth chambers at temperatures ranging from $15{\pm}2^{\circ}C$ to $30{\pm}2^{\circ}C$ (in $5^{\circ}C$ increments). Seven days post inoculation (dpi), a hypersensitivity reaction (HR) was induced in inoculated leaves of PI152225 and S3669 plants maintained at $25{\pm}2^{\circ}C$. Meanwhile, necrotic spots were formed in upper leaves of 33% of PI15225 plants maintained at $30{\pm}2^{\circ}C$, while systemic mottle symptoms developed in 50% of S3669 plants inoculated. By 15 dpi, 25% of S3669 plants had recovered from systemic mottling induced at $30{\pm}2^{\circ}C$. These results demonstrated that resistance to TSWV-Pap can be overcome at higher temperatures in both C. chinense and C. annuum. This is the first study reporting the determination of temperatures at which TSWV resistance is overcome in a C. annuum genetic resource expressing the Tsw gene. Our results indicated that TSWV resistance shown from pepper plants possess the Tsw gene could be overcome at high temperature. Thus, breeders should conduct evaluation of TSWV resistance in pepper cultivars at higher temperature than $30^{\circ}C$ (constant temperature).

• Korean Journal of Medicinal Crop Science
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• v.24 no.4
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• pp.317-322
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• 2016

Background: In the herbal medicine market, Angelica gigas, Angelica sinensis, and Angelica acutiloba are all called "Danggui" and used confusingly. We aimed to assess the genetic diversity and relationships among 14 Angelica species collected from different global seed companies. Toward this aim we developed DNA markers to differentiate the Angelica species. Methods and Results: A total of 14 Angelica species, A. gigas, A. acutiloba, A. sinensis, A. pachycarpa, A. hendersonii, A. arguta, A. keiskei, A. atropurpurea, A. dahurica, A. genuflexa, A. tenuissima, A. archangelica, A. taiwaniana, and A. hispanica were collected. The genetic diversity of all 14 species was analyzed by using five chloroplast DNA-based simple sequence repeat (SSR) markers and employing the DNA fragment analysis method. Each primer amplified 3 - 12 bands, with an average of 6.6 bands. Based on the genetic diversity analysis, these species were classified into specific species groups. The cluster dendrogram showed that the similarity coefficients ranged from 0.77 to 1.00. Conclusions: These findings could be used for further research on cultivar development by using molecular breeding techniques and for conservation of the genetic diversity of Angelica species. The analysis of polymorphic SSRs could provide an important experimental tool for examining a range of issues in plant genetics.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.7
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• pp.450-455
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• 2015

For the practical application of a YBCO superconductor bulk, the superconductor bulk magnet with high magnetic field on a large area surface should be fabricated. To make this, YBCO single crystal bulks with fine $Y_2BaCuO_5$(Y211) particles have been prepared by the top-seed melt growth(TSMG) method with $YBa_2Cu_3O_x$, $Y_2O_3$, and $CeO_2$ mixing precursor. By using $Y_2O_3$ instead of $Y_2BaCuO_5$ as precursor, the manufacturing process became simpler and more economical. The microstructures, trapped field and critical current density of the various conditioned YBCO bulks have been observed, analyzed and measured. The different characteristic values of the several samples have been analyzed from the viewpoint of their microstructures. We have developed a $8{\times}12cm$ size superconductor bulk magnet, up to 3 T class, by using the 4 T class-high field superconducting magnetizer and confirmed the applicability of the transmission level circuit breakers by measuring the strength and speed of the superconductor bulk magnet actuator.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.28 no.4
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• pp.170-174
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• 2018

AlN crystal is been developing in global site for many years and 1 inch diameter wafer was already developed but it is demanding the efforts for the better quality. On the other hand, also the 2-inch size is developing recently to reduce the unit cost for manufacturing and to use to fabrication of the UV LED chips. In this study, we tried to evaluate the possibility of bulk AlN crystals on his thin films by PVT method. The AlN thin film was grown on SiC single crystal 2" wafer by HVPE method. We successfully grew AlN bulk crystal of a thickness of 7 mm using its thin film of a thickness of $10{\mu}m$ as a seed crystal. The resultants of AlN crystals were identified by metallurgical microscope, optical stereographic microscope and DCXRD measurement.

• Korean Journal of Agricultural Science
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• v.45 no.3
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• pp.385-400
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• 2018

Marker-assisted backcrossing (MABC) is useful for selecting offspring with a highly recovered genetic background for a recurrent parent at early generation unlike rice and other field crops. Molecular marker sets applicable to practical MABC are scarce in vegetable crops including tomatoes. In this study, we used the National Center for Biotechnology Information- short read archive (NCBI-SRA) database that provided the whole genome sequences of 234 tomato accessions and selected 27,680 tag-single nucleotide polymorphisms (tag-SNPs) that can identify haplotypes in the tomato genome. From this SNP dataset, a total of 143 tag-SNPs that have a high polymorphism information content (PIC) value (> 0.3) and are physically evenly distributed on each chromosome were selected as a MABC marker set. This marker set was tested for its polymorphism in each pairwise cross combination constructed with 124 of the 234 tomato accessions, and a relatively high number of SNP markers polymorphic for the cross combination was observed. The reliability of the MABC SNP set was assessed by converting 18 SNPs into Luna probe-based high-resolution melting (HRM) markers and genotyping nine tomato accessions. The results show that the SNP information and HRM marker genotype matched in 98.6% of the experiment data points, indicating that our sequence analysis pipeline for SNP mining worked successfully. The tag-SNP set for the MABC developed in this study can be useful for not only a practical backcrossing program but also for cultivar identification and F1 seed purity test in tomatoes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.4
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• pp.666-670
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• 1994

To increase the yield of acetic acid production, the author developed the bacterial strain which could brow well in high concentration of ehtanol from the seed culture using in conventional vinegar production factory. By attenuation of the isolated strain in the broth media containing 5-10% ethanol, we could get the strain which could grow in the broth medium containing 10% ethanol. This strain was identified and named as Acetobacter sp. FM-10, and it's cultural characteristics were also investigated. The medium containing 10% ethanol, 5% glucose and 1% yest extract was suitable for the acetic acid production with Acetobacter sp. FM-10. Optimum temperature and pH for the growth of Acetobacter sp. FM-10. were $30^{\circ}C$ and 5.0, respectively. The acidity of culture medium was reached to 9.0 % after 20 days static cultivation at $30^{\circ}C$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.2
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• pp.123-127
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• 2000

The objective of this study was to develop a linkage map of soybean under the genetic background of Korean soybean. A set of 89 F/sub 5/ lines was developed from a cross between 'Pureunkong', which was released for soy-bean sprout, and 'Jinpumkong 2', which had no beany taste in seed due to lack of lipoxygenase 1, 2, and 3. A linkage map was constructed for this population with a set of 113 genetic markers including 7 restriction fragment length polymorphism (RFLP) markers, 79 randomly amplified polymorphic DNA (RAPD) markers, 24 simple sequence repeat(SSR) markers, and 3 morphological markers. The map defined approximately 807.4 cM of the soybean genome comprising 25 linkage groups with 98 polymorphic markers. Fifteen markers remained unlinked. Seventeen linkage groups identified here could be assigned to the respective 13 linkage groups in the USDA soybean genetic map. RFLP and SSR markers segregated at only single genetic loci. Fourteen of the 25 linkage groups contained at least one SSR marker locus. Map positions of most of the SSR loci and their linkages with RFLP markers were consistent with previous reports of the USDA soybean linkage groups. For RAPD, banding patterns of 13 decamer primers showed independent segregations at two or more marker loci for each primer. Only the segregation at op Y07 locus was expressed with codominant manner among all RAPD loci. As the soybean genetic map in our study is more updated, molecular approaches of agronomically important genes would be useful to improve Korean soybean improvement.

• Molecules and Cells
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• v.25 no.1
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• pp.20-29
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• 2008

Cytoplasmic male sterility (CMS), one of the most important traits in crop breeding, has been used for commercial seed production by $F_1$ hybrid cultivars of pepper (Capsicum annuum L.). To develop reliable molecular markers for allelic selection of the Restorer-of-fertility (Rf) gene, which is known to be a major determinant of pollen fertility restoration in peppers, a sequence of approximately 10 kb flanking an RAPD fragment closely linked to the Rf locus was obtained by genome walking. A homology search revealed that this sequence contained an LTR retrotransposon and a non-LTR LINE-like retrotransposon. Sequencing of this Rf-linked region to search for polymorphisms between a dominant and recessive allele revealed 98% nucleotide sequence identity between them. A third polymorphic haplotype of the Rf-linked sequence, which has 94-96% nucleotide sequence identity with the two previously isolated haplotypes, was identified among a large number of breeding lines. Utilizing polymorphic sequences in the haplotypes, PCR markers were developed for selection of particular haplotypes and used to examine the distribution of the haplotypes in diverse breeding lines, cultivars, and C. annuum germplasms. Surprisingly, the third haplotype was the predominant type in C. annuum germplasms, while its frequency in $F_1$ hybrid cultivars was relatively low. Meanwhile, analysis of breeding lines whose Rf allele genotypes and male-sterility phenotypes were already known revealed that the third haplotype was mainly present in exotic breeding lines that cause unstable male-sterility when combined with sterile cytoplasms.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2006.11a
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• pp.90-91
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• 2006

To reduce the economic impact and control Low pathogenic avian influenza (LPAI), vaccination with inactivated vaccine has been considered in this country. We tried to develop inactivated vaccine with reassorted H9N3 AI virus which has different type of neuraminidase compare to those of field AI virus. Before reassorted vaccine was produced, we confirm the virus as master seed by limiting dilution, RT-PCR and sequencing method. Also, we evaluate the biological characteristics of the virus to find out the possibility of prevention against field infection of AI virus. Finally, we evaluate the safety and efficacy of the vaccine made of reassorted AI virus in the specific pathogen free (SPF) chickens. After limiting dilution, we choose RV7CE4 as a vaccine candidate and compare the gene sequence of this vaccine strain to those of AI05GA which is parents strain. Compared to amino acid sequences of specific gene of AI05GA and RV7CE4, exhibited a high degree of amino acid sequence homology. In the safety and efficacy test, there were no specific clinical signs or mortality. Reassorted H9N3 viruses were reisolated in cloaca swab on 5 days post inoculation. In the vaccine study, once or twice vaccination was performed and challenged with H9N2 field virus (01310). Vaccine has no adverse effect on birds and formed good immune capability which reduce viral shedding in the birds infected with 01310. Based on the above result, we developed reassorted H9N3 vaccine which will efficiently prevent the low pathogenic AIV (H9N2) infection in the poultry farms.