• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.5
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• pp.80-85
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• 2015

Recently, not only in the Middle East and Southeast Asia but in African area, too, industrial plant construction is being actually done. But unlike in Korea, a lot of them are small-scale isolated industrial plants. And because of the characteristics of industrial plants, induction motors' load forms a large part. The influence of stability resulted from the maneuver and operation of induction motors' load may lead to serious result in the isolated system. This study analyzed it through mathematical modeling on induction motors' maneuver phenomena in the isolated system, realized a case system with the E-TAP program, and simulated load follow performances according to the control variables of a generator inside the isolated system.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.237-237
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• 2022

Cynodon transvaalensis belongs to the warm-season grasses and is one of the economically and ecologically important crops. Cynodon species with high heterozygosity are difficult to assemble, so genome research has not been actively conducted. In this study, hybrid assembly was performed by sequencing with Illumina and PacBio. As a result of the assembly, the number of scaffolds and the length of N50 were 1,392, 928 kb, respectively. The completeness of the assembly was confirmed by BSUCO at 98.3%. In addition, as a result of estimating the size of the assembled genome by K-mer analysis (k=25), it was approximately ~413 Mb. A total of 37,060 cds sequences were annotated in the assembled genome, and their functions were identified through blast. After that, we try to complete the assembled genome into a pseudochromosome-level genome through Hi-C technology. These results will not only help to understand the complex genome composition of african bermudagrass, but also provide a resource for genomic and evolutionary studies of grass and other plant species.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.63-63
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• 2019

Tea plant (Camellia sinensis (L.) O. Kuntze) has been cultivated widely in many developing Asian, African, and South American countries, where it is the most widely consumed beverage in the world next to water. It has critical importance to understand the genetic diversity and population sturcutre for effective collection, conservation, and utilization of tea germplasm. In this study, 410 tea accessions collected from South Korea were analyzed using 21 SSR markers. Among 410 tea accessions, 85.4% (310 accessions) accessions were collected from Jeollanam-do. A total of 286 alleles were observed, and the genetic diversity and evenness were estimated to be averagely 0.79 and 0.61, respectively, across all the tested samples. Using discriminant analysis of principal components, the four clusters were detected in 410 tea accessions. Among them, cluster 1 showed higher frequency of rare alleles (less than 1%) than other clusters. Using calculation of the index of association and rbaD value, each cluster showed a clonal mode of reproduction. The result of AMOVA showed that most of the variation observed was within populations (99%) rather than among populations (1%). Our results might contribute to provide data about genetic diversity for the conservation of tea germplasm and for future breeding programs.

• Journal of Plant Biotechnology
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• v.48 no.2
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• pp.115-122
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• 2021

Aspilia africana (Pers) C.D.Adams, a plant used for centuries in many African countries to treat diseases such as osteoporosis, malaria, tuberculosis, and diabetes, is of great pharmaceutical interest, yet there is limited scientific literature on its germination and growth. This research paper describes the effects of different commercial soils on the germination, growth, and chlorophyll content of A. africana. The germination parameters assessed included final germination percentage (FGP), mean germination time (MGT), and germination index (GI). Shoot length, leaf number, and fresh and dry weights were some of the parameters used to assess A. africana growth. The FGP was low and did not vary significantly; the MGT was 7 ~ 10 days; and the GI was significantly higher in PPS soil at 4.61 ± 0.332 days. Aspilia africana plants in HS:PPS soil showed the best overall growth, producing the highest mean leaf number (18.00 ± 1.129), longest mean shoot length (202.43 ± 13.451 mm), and highest mean fresh and dry weights (7.08 ± 1.061 g and 0.629 ± 0.112 g, respectively). The highest chlorophyll content in leaves of A. africana under HS:PPS conditions suggested a higher photosynthetic potential of plants in this soil. The best growth performance of A. africana in the HS:PPS soil could be attributed to a higher amount of certain mineral nutrients such as nitrogen, potassium, and phosphorus in the HS:PPS soil compared to the other soil categories. It is unclear why the FGP of A. africana was low and we recommend an exclusive study to investigate this further.

• Journal of Plant Biotechnology
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• v.49 no.2
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• pp.139-144
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• 2022

The genus Prunus (family: Rosaceae) consists of over 400 plant species and exhibits vast biodiversity worldwide. Given the wide distribution of this genus, its taxonomic classification is important. Anatomical characteristics are conserved and stable and can therefore be used as an important tool for the taxonomic characterization of plants. Therefore, this study aimed to assess and document the anatomical characteristics of the leaf, stem, and seed of P. africana using micrographs and photographs for possible use in the identification, quality control, and phylogenetic analysis of the species. The anatomical sections of a young stem revealed a cortex consisting of isodiametric parenchyma cells, druse crystals, primary vascular bundles, and pith. The mature stem bark majorly consisted of the rhytidome, with the periderm densely arranged in multiple layers; a cluster of stone cells; and sclerenchyma. The leaf sections were hypostomatic, with stomata sizes ranging from 18.90-(22.34)-26.90 × 15.41-(18.40)-21.22 ㎛. The leaf sections showed the presence of characteristic druse crystals, vascular bundles, and mesophyll layers. The pericarp contained the epicarp, mesocarp, and endocarp, with their thickness being approximately 350-400, 300-350, and 30-50 ㎛, respectively. In addition, it contained a seed testa with a thickness of approximately 50-60 ㎛. The morphological and anatomical characteristics observed in P. africana leaves, stems, and seeds in this study could serve as useful data for the taxonomic identification of this species.

• The Plant Pathology Journal
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• v.40 no.1
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• pp.48-58
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• 2024

The oldest and most extensively cultivated form of millet, known as pearl millet (Pennisetum glaucum (L.) R. Br. Syn. Pennisetum americanum (L.) Leeke), is raised over 312.00 lakh hectares in Asian and African countries. India is regarded as the significant hotspot for pearl millet diversity. In the Indian state of Haryana, where pearl millet is grown, a new and catastrophic bacterial disease known as stem rot of pearl millet spurred by the bacterium Klebsiella aerogenes (formerly Enterobacter) was first observed during fall 2018. The disease appears in form of small to long streaks on leaves, lesions on stem, and slimy rot appearance of stem. The associated bacterium showed close resemblance to Klebsiella aerogenes that was confirmed by a molecular evaluation based on 16S rDNA and gyrA gene nucleotide sequences. The isolates were also identified to be Klebsiella aerogenes based on biochemical assays, where Klebsiella isolates differed in D-trehalose and succinate alkalisation tests. During fall 2021-2023, the disease has spread all the pearl millet-growing districts of the state, extending up to 70% disease incidence in the affected fields. The disease is causing considering grain as well as fodder losses. The proposed scale, consisting of six levels (0-5), is developed where scores 0, 1, 2, 3, 4, and 5 have been categorized as highly resistant, resistant, moderately resistant, moderately susceptible, susceptible, and highly susceptible disease reaction, respectively. The disease cycle, survival of pathogen, and possible losses have also been studied to understand other features of the disease.

• Korean Journal of Plant Tissue Culture
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• v.21 no.5
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• pp.303-308
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• 1994

Shoot apical meristem dome explants from cassava plants (Ghanaian local variety) produced somatic embryos at a frequency of 32% when cultured on MS medium supplemented with 2 mg/L 2,4-D. Somatic embryo segments formed secondary embryos at frequencies of up to 93% when cultured on medium containing 1 mg/L 2,4-D for 2 to 3 weeks. Since the somatic embryos were not capable of converting into plantlets, adventitious shoot were induced from the sliced embryo segments by culturing them on medium containing 0.1 to 5 mg/L BA. After 8 weeks of culture, numerous shoots formed on the segments at frequencies up to 100%. The shoots were rooted and successfully transplanted to potting soil.

• Journal of Plant Biotechnology
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• v.50
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• pp.97-107
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• 2023

Malaria remains to be one of the most severe global public health concerns. Traditionally, Aspilia Africana and Warburgia ugandensis have been used to treat malaria in several African countries for millennia. In the current study, A. africana calli (AaC), A. africana in vitro roots (AaIR), A. africana wild leaf (AaWL), and W. ugandensis stem bark (WuSB) were dried and pulverized. Fourier transform near-infrared spectroscopy was used to analyze the powdered samples, while 80% ethanolic extracts of each sample were assayed for antiplasmodial activity (against Plasmodium falciparum strains DD2 (chloroquine-resistant) and 3D7 (chloroquine-sensitive)) and cytotoxicity. WuSB showed the highest antiplasmodial activity (IC₅₀ = 1.57 ± 0.210 ㎍/ml and 8.92 ± 0.365 ㎍/ml against P. falciparum 3D7 and DD2, respectively) and selectivity indices (43.90 ± 7.914 and 7.543 ± 0.051 for P. falciparum 3D7 and DD2, respectively). The highest total polyphenolic contents (total phenolic and flavonoid contents of 367.9 ± 3.55 mg GAE/g and 203.9 ± 1.43 mg RUE/g, respectively) were recorded for WuSB and the lowest were recorded for AaC. The antiplasmodial activities of the tested plant tissues correlated positively with total polyphenolic content. The high selectivity indices of WuSB justify its traditional applications in treating malaria and present it as a good candidate for discovering new antimalarial compounds. We recommend elicitation treatment for AaIR, which showed moderate antiplasmodial activity against P. falciparum DD2, to increase its secondary metabolite production for optimal antimalarial activity.

• Journal of Forest and Environmental Science
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• v.38 no.3
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• pp.184-194
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• 2022

Triplochiton scleroxylon K. Schum is the plant species most affected by logging activities in the East Region of Cameroon due to its market value. This logging has impacted the ecological niche of the fern plant for which limited research has been done. The aim of this study is to contribute towards improving knowledge of fern richness and biomass on T. scleroxylon within the Central African sub-region. Fern data collection was done on 20 felled/harvested T. scleroxylon where, in addition to fern inventory, fern biomass was collected by the destructive method. The diameter and height of T. scleroxylon measured were used as explanatory variables in allometric equations for fern biomass estimation. Fern inventory was characterized using diversity index. Eight fern species were recorded on T. scleroxylon (≈5 species/T. scleroxylon). The minimum diameter where fern could be found is 59.4 cm. The average fern biomass found was 23.62 kg/T. scleroxylon. Pearson correlation coefficient showed a positive correlation (r>0.55) between fern biomass and T. scleroxylon diameter. For allometric equation, the logarithmic model improved better the adjustment than the non-logarithmic model. However, the quality of the adjustment is improved more when only the diameter is considered as an explanatory variable. Fern biomass is estimated to 90.08 kg/ha^-1 with 76.02 kg/ha^-1 being lost due to T. scleroxylon exploitation in the study area. This study is a contribution towards increasing knowledge of fern diversity specific to T. scleroxylon, and also fern biomass contribution to climate change mitigation and the potential carbon loss due to T. scleroxylon exploitation.

• Journal of the Korean Society of International Agriculture
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• v.23 no.5
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• pp.560-569
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• 2011

In Japan, plant genomics research is mainly leaded by the national research institutes. The various structural studies such as rice genome has allowed researchers to analyze useful traits, and to focus their commercialization. With aims to facilitate structural and functional study in plant genome, NIAS (National Institute of Agrobiological Sciences) constructed Poaceae genome DB and RIKEN (Rikagaku Kenkyusho) built DB for Arabidopsis genome and plant full-length cDNA. NIG (National Institute of Genetics) constructed a national biological resources DB (National Bio Resource Project). This compiling DB provides a variety of genome-related research materials for researchers in the field. Recently, as an effort to resolve global issues of food supply and environmental problems, New Agri-genome Project has been performed aiming to develop an innovative agricultural technologies for the quantity, disease resistance and identifying useful genes related to environmental problems. In addition, in order to improve agricultural productivity in developing countries, JIRCAS assisted technical supports for the plant genome research and developed NERICA rice, which is suitable for African area. Such these approaches are expected to contribute to solving the global issues about food, energy and environment in the world.