• Korean journal of applied entomology
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• v.54 no.4
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• pp.345-349
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• 2015

The pest species occurring on the aboveground parts of Phalaenopsis orchids were studied for a period of two years (Aug. 2013 to June 2015) at 9 Phalaenopsis farms in Korea. In total, 10 species of insect pest were identified : Tenuipalpus pacificus Baker, Tyrophagus putrescentiae Schrank, Frankliniella occidentalis Pergande, Frankliniella intonsa Trybom, Thrips tabaci Lindeman, Scirtothrips dorsalis Hood, Pseudococcus dendrobiorum Williams, Pseudococcus longispinus Targioni Tozzetti, Coccus hesperidum L., Limax marginatus $M{\ddot{u}}ller$. T. pacificus occurred in most of the farms surveyed in this study (6). The observation frequency of T. pacificus and F. intonsa were highest, they were observed in 10 out of 96 surveys. Although P. longispinus was only observed to occur on two farms, their observation frequency (9 observations, 9.4%) and density (2-289 per 20 plants) were high. Thus, it seems that T. pacificus, F. intonsa, and P. longispinus are the major pests affecting Phalaenopsis orchid farms in Korea.

• FLOWER RESEARCH JOURNAL
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• v.16 no.1
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• pp.85-92
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• 2008

The air anions generated by potted Cymbidium spp., Cymbidium Meglee 'Ms Taipei' Dendrobium phalaenopsis, Oncidium spp., Phalaenopsis spp., and Sedirea japonicum were investigated, and changes of air anion emission were measured as affected by volume rates of potted orchids put in chambers. The volume rates of 20, 40, 60, and 80% for potted Cymbidium spp. and 25, 50, 75, and 100% for potted Cymbidium Meglee 's Taipei'were used in closed chambers. Air anion emission by Cymbidium spp. ($332/cm^3$) and Cymbidium 's Taipei'($323/cm^3$) was the greatest among the tested six orchid species, followed by Dendrobium phalaenopsis ($250/cm^3$), Oncidium spp. ($203/cm^3$), Sedirea japonicum ($119/cm^3$), and Phalaenopsis spp. ($77/cm^3$). Air anion emission by Cymbidium spp. and Cymbidium Meglee 'Ms Taipei'g increased by 40% and 75%, respectively, and thereafter slightly decrease. Therefore, the volume rates of potted plants put in closed chambers should be less than 40% to compare with species and 30% seems most pertinent considering increasing relative humidity in closed chambers. Air anions were generated the greatest amount by potted Cymbidium genera among the orchids tested.

• The Plant Pathology Journal
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• v.26 no.2
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• pp.194-197
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• 2010

Most orchids are propagated by tissue culture. To survey the viral infection of tissue cultured Orchids, total RNA was extracted from in vitro Cymbridium and Phalaenopsis spp. collected from companies producing tissue-cultured orchids, and RT-PCR analysis was conducted with primer pairs specific to Cymbidium mosaic virus (CymMV) and Odontoglossum ring spot virus(ORSV), which are infecting wide range of orchid genera. The bulb size of Cymbidium infected with CymMV and ORSV was compared with healthy one at 10 months after planting in vitro orchids in the glasshouse. The CymMV or ORSV infection in 97 Cymbidium and 55 Phalaenopsis plants was 84.5 and 89.1 %, respectively. Mixed infection was found in 52.6 and 47.3% of Cymbidium and Phalaenopsis tested, whereas virus-free orchids were 15.5 and 10.9%, respectively. The CymMV and ORSV reduced the bulb size by 2.7-50% depending on the cultivars of Cymbidium. The both viruses caused yellowing, mottle and mosaic with or without necrosis in 4 Cymbidium cultivars.

• Horticultural Science & Technology
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• v.35 no.1
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• pp.21-29
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• 2017

This study was conducted to determine the effects of artificial lighting sources on vegetative growth of Phalaenopsis and Doritaenopsis (an intergeneric hybrid of Doritis and Phalaenopsis) orchids. One - month - old plants were cultivated under fluorescent lamps, cool - white light - emitting diodes (LEDs), or warm - white LEDs at 80 and $160{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. The blue (400 - 500 nm) : green (500 - 600 nm) : red (600 - 700 nm) : far - red (700 - 800 nm) ratios of the fluorescent lamps, cool-white LEDs, and warm-white LEDs were 1 : 1.3 : 0.8 : 0.1, 1 : 1.3 : 0.6 : 0.1, and 1 : 2.7 : 2.3 : 0.4, respectively. Each light treatment was maintained for 16 weeks in a closed plant-production system maintained at $28^{\circ}C$ with a 12 h photoperiod. The longest leaf span, as well as the leaf length and width of the uppermost mature leaf, were observed in plants treated with warm-white LEDs. Plants grown under fluorescent lamps had longer and wider leaves with a greater leaf span than plants grown under cool-white LEDs, while the maximum quantum efficiency of photosystem II was higher under cool-white LEDs. The vegetative responses affected by different lighting sources were similar at both 80 and $160{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Leaf span and root biomass were increased by the higher light intensity in both cultivars, while the relative chlorophyll content was decreased. These results indicate that relatively high intensity light can promote vegetative growth of young Phalaenopsis plants, and that warm - white LEDs, which contain a high red-light ratio, are a better lighting source for the growth of these plants than the cool-white LEDs or fluorescent lamps. These results could therefore be useful in the selection of artificial lighting to maximize vegetative growth of Phalaenopsis plants in a closed plant - production system.

• Plant Resources
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• v.5 no.3
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• pp.176-180
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• 2002

This study was conducted to develop the clonal propagation technique through in vitro culture using by leaf sheath explants of Phalaenopsis grown in vitro. The highest frequency of protocorm-like body (PLB) formation was obtained when explants of leaf sheath were cultured on VW medium containing 30g/L sucrose, 500 mg/L activated charcoal, 150 mVL coconut water, 1 mg/L NAA, 1 mg/L 2ip and 2.5 g/L gelrite. The PLB formation rate of VW medium was highest followed by modified Hyponex medium, and lowest in MS medium. Plantlets induced from PLBs transferred to plastic pots including spagnum moss were well developed.

• Horticultural Science & Technology
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• v.16 no.3
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• pp.361-363
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• 1998

Cymbidium goeringii native to Korea and other orchid plants were pot-grown from spring to autumn under the greenhouse conditions, and were subjected to artificial pollination to elucidate the compatibility by revealing viable seed formation. A notable compatibility was found when Cym. goeringii was selfed and was crossed with either Cym. ensifolium, Cym. kanran, Cym. sinense, Cym. sinense for. albo-jucundissimum, Cym. 'Crystal Cherry Angel', or Cym. 'Anmitsu Hime'. Cym. goeringii, however, did not show such compatibility when crossed with either Cym. faberi, Cym. aloifolium, Dendrobium chrysotoxum, or Phalaenopsis spp. RAPD analysis indicated that taxa relationship between Cym. goeringii and either Cym. faberi or Cym. aloifolium (respective chromosome number, 2n=40) was distant, showing no compatibility, and even more distant in the case of cross-pollination between Cym. goeringii and either Dendrobium chrysotoxum or Phalaenopsis spp. having different chromosome number from all Cymbidium species.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.371-374
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• 2010

The blossom midge, Contarinia maculipennis Felt (Diptera: Cecidomyiidae) originated in Southeast Asia and is present in Japan, the continental USA, and Hawaii. Recently, C. maculipennis was intercepted in Japan, USA and the Netherlands by using orchid flowers imported from Southeast Asian countries. This pest is designated as a quarantine pest in Korea because of its potential damages to vegetables and ornamental plants. In Korea, similar symptoms of damage, which mighty be caused by C. maculipennis, have been investigated in western orchids, especially on Dendrobium phalaenopsis, from Mid-2000s. Official recognition was given to C. maculipennis in 2007, followed by an investigation on the occurrences of C. maculipennis and its damages, mainly on D. phalaenopsis, in 2008~2009. We emphasize caution concerning the possibilities that C. maculipennis could infest flower buds of orchids and carry out management strategies for this pest in the future.

• FLOWER RESEARCH JOURNAL
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• v.17 no.4
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• pp.237-241
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• 2009

This study was conducted to determine injury symptoms of orchids by sulfur dioxide gases, three orchid plants (Phalaenopsis, Cymbidium, Oncidium) were exposed to sulfur dioxide gas in an enclosed growth chambers. Sulfur dioxide gases treatments consist of five different concentrations (0, 5, 10 25, and 50 ppm) and plant exposure of 18 hours with $25{\pm}5^{\circ}C$ air temperature and $50{\pm}5%$ relative humidity. SPAD values for chlorophyll content and percent leaf injury as well as leaf ion exudation were measured before and after the gas treatments. Phalaenopsis leaves showed 23.3% leaf injury at 10 ppm sulfur dioxide gas, whereas Cymbidium and Oncidium showed 4.0 and 4.4% leaf injury under 25 ppm or less, respectively. Major leaf injury symptoms appeared as initial water-soaking under side of the leaf, followed by rapidly progressed complete leaf discolorization or chlorosis. As the gas concentration increased, the SPAD value decreased while ion exudation increased. Cymbidium and Oncidium were resistant to sulfur dioxide gas than Phalaenopsis.

• Horticultural Science & Technology
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• v.31 no.3
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• pp.337-343
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• 2013

The aims of this study were to compare genetic distances among 14 Phalaenopsis varieties using simple sequence repeat (SSR) and sequence-related amplified polymorphism (SRAP) marker systems and to determine the discrimination using SSR. A total of 111 SSR primers and 30 SRAP combinations were initially screened. Twelve SSR primers and thirty SRAP combinations showed high polymorphism among the 14 Phalaenopsis varieties including domestic breeding varieties, conserved in National Institute of Horticultural & Herbal Science (NIHHS). The amplified DNA fragments were separated by denaturing acrylamide gels and detected by silver staining method. A total of 474 polymorphic bands, including 55 by SSRs and 419 by SRAPs, were identified and used for genetic diversity analysis. Polymorphic bands were scored for calculating a simple matching coefficient of genetic similarity and cluster analysis with multi-variate statistical package (MVSP) 3.1. Fourteen Phalaenopsis varieties were classified into three major groups at similarity coefficient value of 0.683 and 0.66 using SRAP and SSR, respectively. Also we could discriminate these domestic breeding Palaenopsis varieties using only SSR 20 and SSR 22. The results indicate that SSR analysis is effective for discrimination among Phalaenopsis varieties and SRAP is useful for genetic diversity when there is no sequence information. These studied SSR and SRAP markers will be useful tools for genotype identification, germplasm conservation and genetic relationship study in Phalaenopsis.

• Horticultural Science & Technology
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• v.17 no.5
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• pp.578-580
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• 1999

The effects of the orchid mycorrhizal fungi isolated from Cymbidium goeringii were investigated on the growth of orchid plants. The plants, a hybrid of Cymbidium kanran Jeju${\times}$C. kanran Nangoku and Phalaenopsis were inoculated with the fungal isolates of Rhizoctonia repens (P1), R. endophytica (P2) and R. repens (P3; different from P1) on the oatmeal agars for two months. Then the orchid plants were cultivated in the greenhouse for eighteen months. The difference of plant growth after cocultivation for two months was not found among the treatments. After cultivation for four months, the growth of hybrid plants of Cymbidium kanran Jeju${\times}$C. kanran Nangoku was observed to be distinguished in the Rhizoctonia repens (P1). After cultivation in the greenhouse for eighteen months, the plant height, the number of shoots, the number of leaves, the number of roots and plant fresh weight of the hybrid of Cymbidium kanran Jeju${\times}$C. kanran Nangoku, inoculated with Rhizoctonia repens (P1), were significantly increased compared to those of the control. The plants inoculated with Rhizoctonia repens (P3) were not different and the plants inoculated with R. endophytica were poor compared to the control. The plant height and fresh weight of the Phalaenopsis, inoculated with Rhizoctonia repens (P1), increased significantly compared to those of the control. Overall, Rhizoctonia repens (P1), was the most effective for the growth of a hybrid of Cymbidium kanran Jeju${\times}$C. kanran Nangoku.