• Korean journal of applied entomology
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• v.39 no.3
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• pp.153-156
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• 2000

Spatial activities of Liriomyza trifolii (Burgess) were investigated weekly using yellow sticky trap which were placed at three different height and monitored during four time periods. Yellow sticky trap placed at plant height caught significantly more L. trifolii (Burgess) than did traps placed at 30 and 60cm above plant height. Diel activities of L. trifolii (Burgess) were monitored with yellow sticky traps at 1- and 2-h intervals during three time periods. Leafminer flight activity in May, July and October peaked from 1400 to 1800 hours, 0800 hours and from 1200 to 1400 hours, respectively. 2nd peak of flight activity only occurred in May. Attraction of L. trifolii (Burgess) for yellow sticky traps was affected by temperature as well as solar intensity. Male of L. trifolii (Burgess) appeared more responsive to yellow sticky traps than female regardless of trap height or time of day.

• Horticultural Science & Technology
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• v.17 no.4
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• pp.485-488
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• 1999

This study was conducted to obtain a basic information on the structural and histological characteristics of Gerbera hybrida Hort. leaf injured by american serpentine leafminer (ASL), Liriomyza trifolii, by using light and scanning electron microscope (SEM). Based on the anatomical observation of leaf blade injured by L. trifolii, the injury process could be divided into three stages. In the initial stage, the punctured tiny holes where ASL layed eggs after suction in the upperside of leaf were observed in the palisade parenchyma. In the middle stage, the hatched larvae made mines in the palisade parenchyma only. In the final stage, the mature larvae grew up making the mines bigger, and just before going out from the epidermis, it injured the inside of leaf containing one layer palisade parenchyma and two layers of spongy parenchyma.

• Korean Journal of Plant Tissue Culture
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• v.28 no.2
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• pp.91-95
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• 2001

Propagules grown at different in vitro culture conditions such as heterotrophic, mixotrophic and photoautotrophic conditions were investigated for growth, total photosynthesis ratio and flowering. Survival rate of propagules after transplanting was higher in photoautotrophic propagules than in the heterotrophic and mixotrophic ones. Total photosynthesis was higher plantlets growth in photoautotrophic (154 mg$CO_2$.mgDW$^{-1}$ h$^{-2}$ ) those grown than in mixotrphpic (148 mg$CO_2$.mgDW$^{-1}$ h$^{-2}$ ) and heterotrophic (102 mg$CO_2$.mgDW$^{-1}$ h$^{-2}$ ) 30 days after transplanting into fields. Day to flowering of the plant cultured in photoautotrophic condition was shortened by 7~10 days than those of heterotrophic and mixotrophic ones. Length of the petiole, number of leaves, leaf area and chlorophyll content were also increased.

• FLOWER RESEARCH JOURNAL
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• v.16 no.1
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• pp.76-84
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• 2008

This study was conducted to find out the cause of discoloration after pressing yellow-colored flowers. Plant materials used were Lilium Asiatic Hybrids, Oncidium spp., Rosa hybrida, $Tulipa{\times}gesneriana$, Antirrhinum majus, Dianthus caryophyllus, Freesia hybrida, Zantedeschia elliottiana, Gerbera jamesonii, Helianthus annuus, and Ranunculus asiaticus. Thickness, ratio of length to width, and water content of petals did not considerably affect discoloration of pressed flowers. Expression of yellow color in petals was caused by carotenoids in Lilium Asiatic Hybrids, Oncidium spp., Rosa hybrida and $Tulipa{\times}gesneriana$, by flavonoids in Antirrhinum majus, Dianthus caryophyllus, Freesia hybrida and Zantedeschia elliottiana, and by coexistence of carotenoids and flavonoids in Gerbera jamesonii, Helianthus annuus and Ranunculus asiaticus. Carotenoids that expressed yellow color in petals affected significantly on discoloration in pressed flowers containing carotenoids alone or both carotenoids and flavonoids. However, discoloration was hardly ever found in yellow-colored species as affected by flavonoids. Dark treatment was effective for almost perfect preservation in color of pressed flowers, while light treatment resulted in severe discoloration.

• Journal of agriculture & life science
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• v.45 no.6
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• pp.73-80
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• 2011

To investigate the characteristics of plant growth and flower quality of gerbera 'Sunny Lemon' by amount of nutrient solution, young seedling plants, 'Sunny Lemon' were transplanted to rock-wool and medium of peat moss and perlite mixed with 1 to 2 and they were acclimatized in greenhouse during about 1 month. Nutrient solution supplied to the plants is sonneveld solution of 1/2 concentration and treatments launched June 24, 2010 when average plant height was $20{\pm}1cm$. Nutrient contents as a standard for starting point of irrigation by time domain reflectometry (TDR) were determined with 60-65%, 70-75%, and 80-85%. Results of growth during vegetative growth, plant height, leaf width and leaf number increased by 10% in rockwool, but they were not significantly different. As for plant growth depending on nutrient content, 80-85% treatment showed the highest values. Leaf number increased by 60%, and leaf width and plant height had a about 40% increase than initial growth. Effectiveness for flower quality, yield and days to flowering were superior when nutrient content of media was higher than in the others. Especially, average days to flowering in 80-85% content was advanced by 7-10 days compared to the day in 60-65% treatment. The total amount of nutrient supply per plant was higher in mixed medium than in rockwool, but change patterns of EC and pH were enhanced in rockwool. Based on our results, we recommended that growth, cut flower, and yield of gerbera 'Sunny Lemon' were more effective when nutrient content of mixed medium was maintained at 80-85%.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1300-1305
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• 2011

The study was conducted to investigate the characteristics of flower quality and yield of gerbera 'Sunny Lemon' by mutrient solution strength and media of nutrient solution. The plant growth of 'Sunny Lemon' showed the highest values in the media of rockwool and perlite 1: peatmoss 2. Especially the yield of cut flowers for a year was more than 60 flowers and the flower longevity was over 10 days irrespective of nutrient solution concentration in the two media. There were no significant differences of plant characteristics in the nutrient concentration of 1/2 and 1 times, and the mineral nutrient contents showed similar values. Therefore, we recommended the media of perlite1: peatmoss2 with the concentration of 1/2 times for economical use. The rockwool media was not appropriate because of the weak buffer capacity like EC and pH.

• Korean journal of applied entomology
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• v.40 no.2
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• pp.149-153
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• 2001

We surveyed on the host plants of Fungus gnat, Bradysia app. and found 21 species in the greenhouse and field. These are as follows: Cucumis sativus L., Cucumis melo L., Citrullus lanatus T., Cucurbita moschata F., Lycopersicon esculentum M., Capsicum annuum L (Pepper), Capsicum annuum L (Paprika), Lillium longiflorum T., Dianthus caryophyllus L., Rosa hybrida H., Gerbera jamesonii B., Chrysanthemum morifolium R, Phalaenopsis schilleriane R., Gladiolus grandiflours H., Zingiber officinale R., Cnidium officinale M., Canavalia gladiata DC., Angelica utilis M., Polygonatum odoratum D., Pinus densiflora S., and Pinus thunbergii P. Fungus gnat larvae cause damages to the root and promote decay and wilt by feeding on the roots and burrowing in plant tissue.

• The Korean Journal of Mycology
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• v.23 no.3 s.74
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• pp.246-256
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• 1995

Phenotypic characteristics, pathogenicity and fungicides resistance of fifty one isolates of Botrytis cinerea obtained from various host plants were observed and determined. The relationships between these characteristics were also investigated on the basis of isolation host plants. The isolates of B. cinerea varied in the capacity of sclerotia formation and sporulation. The pathogenicity of 44 isolates from tomato, cucumber, and strawberry was significantly stronger with 3.2 cm in average diameter of necrotic lesions on cucumber leaves than that of seven isolates from other host plants such as orange, gerbera, ginseng, kiwi, grape, pear and from butter with 1.8 cm in average diameter of necrotic lesions. Benomyl resistance of 12 isolates from tomato plants was much higher with the $EC_{50}$, 562 ppm than that of 19 isolates from various host plants. Diethofencarb resistance, however, of 11 isolates from strawberry plants was highest with the $EC_{50}$, 210 ppm among isolates from other host plants. Polygalacturonase activity varied among isolates in the range of 0 to 103 unit and that of isolates from tomato, cucumber and strawberry was slightly lower than that of isolates from other host plants. No significant relationship between pathogenicity and fungicides resistance, polygalacturonase activity was found among 51 isolates of B. cinerea. Isozyme patterns of polygalacturonase produced from two strongly and weakly pathogenic isolates (FC122, KC6) were slightly different depending upon carbon sources during cultivation.

• Research in Plant Disease
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• v.28 no.4
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• pp.231-236
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• 2022

Oxypetalum coeruleum, commonly known as Tweedia, is a perennial herbaceous plant of the Apocynaceae family native to southern Brazil and Uruguay. Tweedia plants are grown as one of the most popular ornamental flowers for floral arrangement in Korea. In May 2021, several tweedia plants in a single greenhouse in Gimje, Jeollabuk-do were found to show virus-like symptoms including necrotic rings, vein-clearing, chlorotic mottle, and mosaic on the leaves, and necrosis on the stems. Here, we have identified tomato spotted wilt virus (TSWV) in symptomatic tweedia leaves by applying high-throughput RNA sequencing. In the result, a single infection by TSWV was verified without mixed infections of different virus species. To confirm the presence of TSWV, a reverse transcription polymerase chain reaction was performed with a specific primer set to the N gene of TSWV. The complete genomic sequence of L, M, and S segments of TSWV 'Oxy' isolate were determined and deposited in GenBank under accession numbers LC671525, LC671638, and LC671639, respectively. In the phylogenetic tree analysis by maximum likelihood method, 'Oxy' isolate showed a high relationship with TSWV 'Gumi' isolate from Gerbera jamesonii in Gyeongsangbuk-do, Korea; for all three RNA segments. To our knowledge, this is the first report of TSWV infection of O. coeruleum in Korea.