• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10b
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• pp.11-12
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• 2001

The Maori people were early New Zealand settlers of Polynesian descent. The incidence of non-infectious diseases appears to have been low in these people, perhaps in part due to the presence of protective chemical constituents within their food plant supply. Three of the tropical crops they introduced are still eaten here today:the sweet potato of kumara (Ipomoea batatas), the taro (Colocasia esculenta) and the cabbage tree or ti (Cordyline terminalis).(omitted)

• Journal of Microbiology and Biotechnology
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• v.21 no.7
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• pp.697-702
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• 2011

A strain of the cyanobacterium Arthrospira was isolated from Lake Chahannaoer in northern China and was characterized according to microscopic morphology, photosynthetic oxygen-evolving activity, growth rate, and nutritional profile. Compared with thermophilic Arthrospira species occurring naturally in tropical and subtropical lakes, this isolate is mesophilic and grows optimally at ${\sim}20^{\circ}C$. The total protein, fatty acid, phycocyanin, carotenoid, and chlorophyll a contents were 67.6, 6.1, 4.32, 0.29, and 0.76 grams per 100 grams of dry weight, respectively. The strain is rich in polyunsaturated fatty acids (PUFAs). An essential omega-3 fatty acid, docosahexaenoic acid (DHA), was detected, and ${\gamma}$-linolenic acid (GLA) and DHA accounted for 28.3% of the total fatty acid content. These features of this newly isolated strain make it potentially useful in commercial mass culture in local areas or as a biofuel feedstock. It is also an alternative resource for studying the metabolic PUFA pathways and mechanisms of cold stress tolerance in cyanobacteria.

• The Plant Pathology Journal
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• v.20 no.4
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• pp.240-243
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• 2004

White rot on Allium crops recently had a high incidence with incrensed cultivating areas of tropical garlic types in Korea. Two types of Sclerotium have known as causal agents that produce different size and shapes of sclerotia in infested fields. Therefore, we developed a new method for isolation of sclerotia from infested field soils that can be used for ecological study of Sclerotium spp. and establishment of control strategy. Soil samples collected from heavily infested fields were evenly mixed and placed on a automatic sieve shaker connected with tap water, After 10 min of shaking, residues on 0.5 mm and 0.25 mm sieves were separately collected and suspended with 70% sugar solution, which method floats sclerotia in aqueous layer, Then, floated fraction was carefully separated and mixed with a same volume of 1% sodium hypochlorite solution to differentiate with organic materials. This method provides a direct count of sclerotia under a dissecting microscopy.

• Plant Biotechnology Reports
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• v.5 no.3
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• pp.245-254
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• 2011

This study describes an efficient protocol for Agrobacterium tumefaciens-mediated transformation of two subgroups of genotype AAA bananas (Musa acuminata cv. Pei Chiao and Musa acuminata cv. Gros Michel). Instead of using suspension cells, cauliflower-like bud clumps, also known as multiple bud clumps (MBC), were induced from sucker buds on MS medium containing $N^6$-Benzylaminopurine (BA), Thidiazuron (TDZ), and Paclobutrazol (PP333). Bud slices were co-cultivated with A. tumefaciens C58C1 or EHA105 that carry a plasmid containing Arabidopsis root-type ferredoxin gene (Atfd3) and a plant ferredoxin-like protein (pflp) gene, respectively. These two strains showed differences in transformation efficiency. The EHA105 strain was more sensitive in Pei Chiao, 51.3% bud slices were pflp-transformed, and 12.6% slices were Atfd3-transformed. Gros Michel was susceptible to C58C1 and the transformation efficiency is 4.4% for pflp and 13.1% for Atfd3. Additionally, gene integration of the putative pflp was confirmed by Southern blot. Resulting from the pathogen inoculation assay, we found that the pflp transgenic banana exhibited resistance to Fusarium oxysporum f. sp. cubense tropical race 4. This protocol is highly advantageous to banana cultivars that have difficulties in setting up suspension cultures for the purpose of quality improvement through genetic transformation. In addition, this protocol would save at least 6 months in obtaining explants for transformation and reduce labor for weekly subculture in embryogenic cell suspension culture systems.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.3
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• pp.277-285
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• 1986

A total of 16 varieties from Korea and Indonesia were tested at Suwon, Korea (126$^{\circ}$19'E, 37$^{\circ}$16'N and 37m above sea level) and Bali, Indonesia (115$^{\circ}$ 14'E, 8$^{\circ}$42'S and 10m above sea level). Japonica-type varieties showed pre-matured heading at Bali, tropical zone, while Bulu varieties showed no heading at Suwon, temperate zone. The varieties of Indica-type and Ind./Jap. showed faster heading in tropical zone than in temperate zone. Dry matter of the varieties weighed more difference among varietal groups in tropical than in temperate area, while plant height responsed differently depending on variety and test region.

• Korean Journal of Plant Taxonomy
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• v.46 no.2
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• pp.163-174
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• 2016

Gnetum (Gnetaceae, Gnetales) is a gymnosperm genus with ca. 35 species distributed in tropical forests around the world. Due to its dioecious habit and lack of diagnostic characters from vegetative tissue, the identification of Gnetum species is not easy without seeds or reproductive structures. To identify and verify their phylogenetic positions, we applied DNA barcoding to Cambodian Gnetum collections gathered between 2010 and 2015, with previously designed cp matK gene primers. We newly sequenced partial matK sequences from 72 Gnetum collections, 43 out of 72 from Cambodia, and analyzed 115 Gnetum accessions using the neighbor-joining method. The resulting neighbor-joining tree categorized Cambodian Gnetum samples into three clades of species: G. macrostachyum, G. montanum, and G. aff. gracilipes. The recognition of G. aff. gracilipes in Cambodia is reported here for the first time. Taxonomic information for the three recognized Cambodian Gnetum species is provided and the benefits of the taxonomic reevaluation assisted by DNA barcoding are emphasized in this work.

• The Korean Journal of Ecology
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• v.27 no.2
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• pp.57-60
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• 2004

There are 474 species of native vascular plant distributed in offshore islands in Shandong Province, which belong to 262 genera and 82 families. The distribution types of genera of seed plant were classified into 15 types. Temperate characteristic is dominant in the flora of offshore islands and tropical characteristic ranks secondary. Therefore, some islands play the role of stepping islands. Furthermore, 98.85% of the total genera are monotypic or bitypic which shows the offshore habitat heterogeneity in Shandong Province.

• Journal of Plant Biotechnology
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• v.6 no.3
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• pp.189-192
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• 2004

Adventitious multiple shoots were developed from leaf, petiole and internode explants of Geophila reniformis D. Don. on MS medium supplemented with various concentrations of $N^6$-benzylaminopurine (BAP) or Kinetin (KIN) alone or in combination with indole-3-acetic acid (IAA). Leaf showed maximum organogenetic potential, followed by petiole and internode. Murashige and Skoog (MS) medium supplemented with 22.22 $\mu{M}$ BAP and 4.57 $\mu{M}$ IAA induced maximum shoot buds from leaf explants. Internodal segments showed low potential of direct organogenesis. The regenerated shoots rooted the best in presence of 10.75 - 13.44 $\mu{M}$ $\alpha$-naphthalene acetic acid (NAA) along with 2.22 $\mu{M}$ BAP, and were successfully established in the field with a survival rate of 89.11%.

• Plant Biotechnology Reports
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• v.3 no.2
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• pp.135-138
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• 2009

Cell cultures of Cayratia trifolia (Vitaceae), a tropical lianas, were maintained in Murashige and Skoog's medium containing $0.25mg\;1^{-1}$ NAA, $0.2mg\;1^{-1}$ kinetin and casein hydrolysate $250mg\;1^{-1}$. Cell suspension cultures of C. trifolia accumulate stilbenes (piceid, resveratrol, viniferin, ampelopsin), which on elicitation by any of $500{\mu}M$ salicylic acid, $100{\mu}M$ methyl jasmonate, $500{\mu}M$ ethrel and $500mg\;1^{-1}$ yeast extract, added on the 7th day, were enhanced by 3- to 6-fold ($5-11mg\;1^{-1}$) by the 15th day.

• Korean Journal of Plant Taxonomy
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• v.33 no.4
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• pp.309-338
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• 2003

China, the largest country in East Asia, has a pteridoflora of over 2000 species, belonging to about 220 genera in 63 families. There are about 28 East Asiatic genera of Pteridophytes and 6 genera specifically endemic to China. Most of these genera are oligotypic or monotypic groups. Five distribution patterns of the East Asiatic genera are distinguished, i.e., I. Sino-Himalayan type, 10 genera; II. Sino-Japanese type, 4 genera; III. Japan-Himalayan type, 6 genera; IV. Temperate East Asiatic type, 3 genera; and V. Tropical East Asiatic type, 5 genera. The Chinese endemic genera are mainly distributed in southwestern China. The distribution, ecology, taxonomy, and systematics of these genera are discussed.