• The Korean Journal of Mycology
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• v.43 no.1
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• pp.20-25
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• 2015

This study was conducted to investigate diversity of orchid endophytic fungi from roots of two terrestrial orchids, Cypripedium japonicum and Cypripedium macranthum in Korea. The endophytic fungi were identified using morphological and DNA sequences isolated from the roots. Totally, 11 taxa of the endophytic fungi were identified from the roots of C. japonicum and 15 taxa from C. macranthum. Three species of the fungi were common in both host species; Leptodontidium orchidicola, Humicola fuscoatra var. fuscoatra, Umbelopsis dimorpha. Six species of the fungal isolates were the first report in Korea; Oidiodendron echinulatum, Pseudogymnoascus roseus, Geomyces vinaceus, Cryptosporiopsis ericae, U. dimorpha, Chaetomium cupreum.

• The Plant Pathology Journal
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• v.17 no.6
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• pp.325-328
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• 2001

Gelatin particle agglutination test (GPAT) was used to detect Cymbidum mosaic virus (CymMV) in Cattleya plants. Gelatin particles were coated with purified anti-CymMV immunoglobulin of 25-100 $\mu\textrm{g}$/ml and were subjected to several different concentrations of purified CyMfV as well as varying dilutions of orchid leaf extracts. The GPAT detected purified CymMV up to a minimum concentration of 10 $\mu\textrm{g}$/ml. CymMV was detected from crude sap extract of infected Cattleya leaves and roots up to 1:51,200 and 1:25,600 dilutions, respectively. However, the optimum range of leaf and root sap dilutions was between 50-100. Non-specific reactions were not encountered from any of the healthy orchid plants tested. The entire GPAT process was completed within 2-3 hours. This test was found to be very useful for the detection of CymMV in orchids because it is sensitive, economical, and easy to perform.

• Journal of the Korean Solar Energy Society
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• v.35 no.5
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• pp.49-56
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• 2015

In this study a hybrid heating system based on geothermal source and solar heat was developed in order to save energy for greenhouse heating and its field performance was evaluated. Developed system are composed of following parts: water tank, heat exchanger, heat pump, fan coil unit and heat storage unit. The working performance test was carried out in a greenhouse cultivating oriental orchids being managed by $23^{\circ}C$. Field performance test results showed that average heating coefficient of performance ($COP_h$) was 3.4 for the period from mid-January to mid-March 2013. Heating coefficient of performance ($COP_h$) of developed hybrid heat pump system was more sensitive to water tank temperature than outside air temperature. This study showed that developed hybrid heat pump system has a potential to save the heating costs up to 91% compared to conventional agricultural oil heaters.

• Korean Journal of Agricultural Science
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• v.33 no.2
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• pp.97-106
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• 2006

To strengthen the competitiveness of agricultural sector of the Korea, the direction of market trends on agriculture of the Malaysia was reviewed. The most dominating agricultural area in value is palm oil products, and forest products, sea products poultry products and rubber products is in order. The cultivated area of highest two top plants, oil palm and rubber, was about 4.4 million hectares in 2005, but it is decreasing year by year. Comparatively, rice field, pine apple and fruits tree cultivating area is increasing in tendency by the year. Among all the agricultural products, those items such as pork meat, poultry, egg were self-sufficient, rice, fruits, vegetables and sea products were about 70 to 80% self-sufficient, and beef meat, goat meat and milk were below 20% self-sufficient. Most of the grains, such as wheat, rice, barley, corn etc. and their processed food were imported. Also, temperate fruits such as apple, pear, and water cultivated as well as sprouting vegetables are imported. Ornamental products as cutting flowers and orchids are exported to mainly to the Singapore, but high quality temperate fruits and vegetables are imported from Australia. Oil palm exportation covers the balance of the other items imported and obtaining the foreign money as well in Malaysia.

• Journal of Plant Biotechnology
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• v.40 no.1
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• pp.27-36
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• 2013

We isolated and functionally characterized a Dendrobium Actin1 (DmACT1) promoter that drives strong gene expression in the orchid genus Dendrobium. A genomic fragment containing the region 3227 bp upstream of the coding region of DmACT1 was obtained by inverse PCR. Detailed comparison of the full-length cDNA and genomic sequences revealed that DmACT1 has a 1374 bp first intron in the 5' UTR. However, the 5' flanking sequences upstream of the coding region showed no obvious sequence similarities compared to those of known promoters, including plant actin promoters. Serial deletion constructs of the 5' flanking region from the translation initiation codon were fused to the coding sequence of a GUS/luciferase fusion reporter to identify the regulatory elements necessary for promoter activity. Transient assays in the flowers of Dendrobium revealed that the 5' UTR-intron greatly enhanced promoter activity. Moreover, the DmACT1 promoter with its 5' UTR-intron yielded approximately 10-fold higher reporter activity than the rice Act1 promoter-intron. Our data suggest that the DmACT1 promoter with its 5' UTR-intron is a useful tool for strong expression of transgenes in Dendrobium orchids.

• Journal of Plant Biotechnology
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• v.39 no.4
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• pp.219-224
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• 2012

Alstroemeria plants are widely cultivated in many countries especially in Western Europe and North America and popularity has increased in recently due to its long-base life, large variety of colors and low energy requirement during cultivation period. So far, more than 60 species have been released on the commercial market in the world. To meet the demand of consumer and develop the elite Alstroemeria cultivars, conventional breeding including cross-hybridization and selection as well as mutation breeding were used. However, as other important ornamental plants such as lily, rose, carnation and orchids accepted the biotechnological methods, this newly-born approach should be applied and developed an optimized the genetic transformation system. Then, this biotechnological approach can be fused with the conventional breeding methods and thus can be contributed to the production of elite Alstroemeria plants containing agriculturally good genetic traits which are useful for the both farmers and consumers in the future. In this paper, we reviewed the botanical and genetical features of Alstroemeria plants and its biotechnological approaches in the last decades.

• Plant Resources
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• v.6 no.2
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• pp.144-148
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• 2003

Germination efficiency, such as days to germination and conditions for the hybrid seeds, was tested after hybrid seeds were sown on the medium. Seeds were germinated from 67 to 126 days after seeding in all cross combinations, and germination condition was different among hybrid combinations. There was big difference on days to germination based on the different media, that is, days to germination in the hyponex medium was shorter than that in the Knudson C medium. Mutants such as MMS and NaN$_3$ were used to cause mutation. Germination occurred with 0.1 % NaN$_3$ and MMS. However, even though germination occurred in other treatments (0.01 % and 0.2% of NaN$_3$ and MMS), brownish phenomenon was intense, or did not proceed and got worse after 4-5 months of seeding. In addition, it was performed to choose appropriate medium for the growth of Cymbidium rhizome whose media adaptability is more different than other orchids. Different concentration of NAA and Kinetin was used. As a result, C. goeringii hybrid showed difference for the concentration of NAA and Kinetin combination.

• Mycobiology
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• v.45 no.4
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• pp.312-317
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• 2017

Orchidaceous plants have symbiotic relationships with endophytic fungi, including mycorrhizal fungi, which play important roles in the seed germination and growth of the host plants. In this study, endophytic fungal communities isolated from the roots of Cephalanthera longibracteata collected from three different sites in Korea were analyzed, and it was determined whether fungal communities were preferentially correlated with the sites. The fungal isolates were identified by sequence analysis of the internal transcribed spacer regions of rDNA. In total, 30 species of endophytic fungi, including two species of mycorrhizal fungi belonging to the genus Tulasnella, were identified. Leptodontidium orchidicola showed the highest frequency and was isolated from all root samples. Species diversity and richness were not significantly different among sites. However, the community structure of the endophytic fungi significantly differed among sites, suggesting that the site characteristics affected the community composition of the endophytic fungi colonizing the roots of C. longibracteata. Our findings will aid in developing methods involving the use of symbiotic fungi for orchid conservation and restoration in native habitats.

• The Plant Pathology Journal
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• v.35 no.5
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• pp.498-507
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• 2019

Odontoglossum ringspot virus (ORSV) is a member of the genus Tobamovirus. It is one of the most prevalent viruses infecting orchids worldwide. Earlier studies reported the genetic variability of ORSV isolates from Korea and China. However, the evolutionary rate, timescale, and phylogeographical analyses of ORSV were unclear. Twenty-one coat protein (CP) gene sequences of ORSV were determined in this study, and used them together with 145 CP sequences obtained from GenBank to infer the genetic diversities, evolutionary rate, timescale and migration of ORSV populations. Evolutionary rate of ORSV populations was $1.25{\times}10^{-3}nucleotides/site/y$. The most recent common ancestors came from 30 year ago (95% confidence intervals, 26-40). Based on CP gene, ORSV migrated from mainland China and South Korea to Taiwan island, Germany, Australia, Singapore, and Indonesia, and it also circulated within east Asia. Our study is the first attempt to evaluate the evolutionary rates, timescales and migration dynamics of ORSV.

• Korean Journal of Plant Taxonomy
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• v.49 no.1
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• pp.96-99
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• 2019

The species diversity of Orchidaceae is believed to be extremely high in Myanmar. Like in other plant groups, little basic inventory work has been done thus far. During floristic surveys conducted in Popa Mountain Park (Mandalay Region), Natma Taung National Park (Chin State), and in the Ywangan area (southwestern Shan State), we encountered two interesting orchid species which were determined to be new generic records in the flora of Myanmar. Thuniopsis cleistogama was previously considered endemic to Yunnan Province (China) and was only known from the type locality. However, here the species is newly reported from two localities in central and western Myanmar. Disperis neilgherrensis is known from several widely scattered localities in tropical and subtropical Asia. This tiny orchid species was discovered in the Ywangan area in the southwestern area of the Shan State of Myanmar. These two species will be valuable additions to the updated checklist of the orchids of Myanmar.