• The Korean Journal of Mycology
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• v.27 no.3 s.90
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• pp.198-205
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• 1999

Cucurbitaceous vegetable crops grown in greenhouses in Korea were surveyed from 1995 to 1997. Incidence of Sclerotinia rot was as high as $30{\sim}70%$ at its maximum on Cucumis melo var. reticulatus (netted melon), Cucumis sativus (cucumber), Cucurbita moschata (pumpkin) and Cucurbita pepo (summer squash) but relatively low on Citrullus lanatus (watermelon) and Cucumis melo var. makuwa (oriental melon). Symptoms of Sclerotinia rot developed on stems of all the cucurbits, fruits of five cucurbits except C. lanatus, petioles of two Cucurbita spp. and leaves of C. moschata. A total of 126 isolates of Sclerotinia sp. were obtained from the lesions and identified as Sclerotinia sclerotiorum based on the morphological and cultural characteristics. The fungus was very frequently isolated from stems and fruits of the cucurbits but rarely from petioles and leaves. Six isolates of the fungus were pathogenic to six cucurbits tested although there was some difference in virulence among the isolates to some of the hosts. C. lanatus was the most susceptible to the isolates, whereas C. melo var. makuwa was the most resistant. C. melo var. reticulatus and C. sativus were relatively susceptible to the isolates, and C. moschata and C. pepo relatively resistant.

• Korean journal of food and cookery science
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• v.23 no.5
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• pp.685-695
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• 2007

The purpose of this study was to develop an excellent salad dressing using grape seed oil, which contains high levels of unsaturated fatty acids. First, a vinaigrette was made with grape seed oil and vinegar and divided into five portions. Then, five types of mirepoix au maigre ($M_1,M_2,M_3,M_4,M_5$) were made with apple, onion, carrot, garlic, tomato puree, and tomato ketchup by mixing in a main material vessel. The samples were then allowed to ripen for three days. The control group $M_1$ was named $GD_1$, and the experimental groups $M_2,\;M_3,\;M_4,\;and\;M_5$ were named $GD_2,\;GD_3,\;GD_4,\;and\;GD_5$. respectively. To measure receptiveness, a sensory test was conducted using a 7 point category scale. The test concentrated on flavor, taste, color, agreeability, aftertaste, and overall acceptability: the panel consisted of 15 subjects According to the results, $GD_4$ had the best flavor, color and agreeability. The samples with the most preferred taste and aftertaste were $GD_4\;and\;GD_5$. Between $GD_4\;and\;GD_5$, there were no noticeable differences in taste, aftertaste, or overall acceptability, but differences in color and agreeability did exist. Thus, $GD_4$ proved to be the most favorable product. To determine the best complementing vegetables for $GD_4$ yam($VE_1$), broccoli sprouts($VE_2$), mustard leaves($VE_3$), beet leaves($VE_4$), cucumber($VE_5$), and lettuce(VE6) were selected as samples, and a sensory test was conducted. Each vegetable has its own peculiarities. According to the results, $VE_2$ had the nicest vegetable fragrance recording the highest mean value. The vegetable with the most preferred taste, aftertaste, and agreeability were $VE_2\;and\;VE_6$. $VE_1\;and\;VE_6$ had the nicest color and contained the brightest color as well. The highest overall acceptability was awarded to $VE_2\;and\;VE_6$ and there was no remarkable difference between thorn at a level of 0.05. In conclusion, $VE_2\;and\;VE_6$ were the best complementing vegetables with grape seed oil dressing. However, to commercialize such a dressing, many follow-up studies must be conducted.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.4
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• pp.204-208
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• 2006

This study is to describe continuous-flow analysis (CFA) for the determination of nitrate using hydrazine-copper in plant material and to test precision of this method compared with that of methods, which are RQflex method and salicylic acid method. Samples were leaves of watermelon, cucumber, melon and tomato. Nitrate values measured by the RQflex method were greater than those measured by CFA or salicylic acid method. The correlation of nitrate values between those measured by CFA and salicylic acid method was $R^2=0.9671$, and those measured by CFA between those measured by RQflex method was $R^2=0.9739$. Recovery rate of nitrate added to tissue extract by CFA method was $99.7{\pm}0.25%$.

• Korean journal of applied entomology
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• v.19 no.3 s.44
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• pp.175-179
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• 1980

Soybean stunt virus (SSV) was newly isolated in Korea from naturally infected soybeans (Glycine max). The main symptoms caused by this virus on soybean cultivars are crinkling, mild mottling and reduction in plant size. This virus induced local lesion on the inoculated leaves of Chenopodium amaranticolor, C quinoa and Vigna sinensis, and mosaic symptoms on Nicotiana tabacum (Bright yellow, KY-57). The virus was inactivated at 60C, and was infectious at dilution of $10^3$. Extract juice became infective 3 days later at room temperature. The virus was transmitted by green peach apid (Myzus persicae). This virus closely is related serologically to cucumber mosaic virus. The virus particles observed in the electron microscopy were spherical types of 30mm in diameter.

• Journal of the Korean Dietetic Association
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• v.16 no.1
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• pp.49-61
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• 2010

The purpose of this study was to determine basic information on the microbiological quality of environmentally friendly vegetables used in school foodservices. Comparisons were made on the microbiological quality of eight different kinds of vegetables grown by environmentally friendly agricultural methods and ordinary agricultural methods to determine if there were significant differences. In the raw materials, aerobic plate counts were as follows: lettuce 4.58~7.43 log CFU/g, winter plowing chinese cabbage 5.61~7.36 log CFU/g, Korean leek 5.81 log CFU/g to TNTC (too numerous to Count), cabbage 5.93~6.43 log CFU/g, sesame leaves 3.15~5.23 log CFU/g, cucumber 5.00~5.79 log CFU/g, cherry tomato 2.96~5.40 log CFU/g, paprika 1.30~3.52 log CFU/g. In the comparison of the microbiological quality between environmentally friendly and ordinary agricultural vegetables, their acceptable ratio was the same (81.3%) and the mean aerobic plate counts was not significantly different. In the comparison of the microbiological quality between the leafy vegetables and the fruity vegetables, the fruity vegetables had a 100% acceptable ratio regardless of the agricultural method used to grow them, while the leafy vegetables had an acceptable ratio of 70%. In terms of the aerobic plate counts, the leafy vegetables had significantly higher counts; the leafy vegetables 5.87${\pm}$1.18 log CFU/g, the fruity vegetables 4.12${\pm}$1.54 log CFU/g.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.73.1-73
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• 2003

In order to cultivate watermelon on farm, grafting of the watermelon seedling to the watermelon stock is necessary because the watermelon root is less viable than the root of watermelon stock. Recently, commercially important watermelon varieties further require a resistant stock against especially CGMMV to control the heavy loss of the total yield of watermelon by CGMMV infection. Therefore, we have set out a project to develop a CGNEMV-resistant watermelon stock. We have successfully transformed dozens of watermelon stocks (gongdae) during last two years especially using a cDNA encoding the coat protein of CGMMV (cucumber green mottle mosaic virus). Recently we have tested levels of resistance of those watermelon stocks against CGMMV infection. For CGMMV inoculation, the leaves of one month old gongdae (T1) were rubbed by carborundum mixed with the CGMMV. A total of 140 plants (T1) were exposed to the CGMMV and we found that ten plants were completely resistant to virus infection. This is the first report that by genetic engineering a cucubitaceae crop resistant to CGMMV infection is ever developed. Further information will be provided in the poster.

• Korean Journal Plant Pathology
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• v.13 no.3
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• pp.152-159
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• 1997

Six pathogenic Pythium isolates obtained from diseased ginger rhizomes were identified as Pythum myriotyrum Drechsler based on various morphological and physiological characteristics. The isolates showed strong virulence on underground parts of buds, crowns, rhizomes, roots and aerial parts of leaves and stems as well. The isolates caused rot of germinated seeds of 10 different crops tested, including cucumber and pepper, and markedly inhibited seedling growth of 3 crops tested, including corn and barley. Maximum, optimum and minimum growth temperatures for P. myriotylum were 39~45$^{\circ}C$, 33~37$^{\circ}C$ and 5~7$^{\circ}C$, respectively. Optimum pH for the growth was 6~7. Mycelial linear growth was most rapid on V-8 juice agar, but aerial mycelia were most abundant on PDA and corn meal agar. Zoosporangial and oogonial formation was greatest on V-8 juice agar. Optimum temperatures for the production of zoosporangia and oogonia were 20~35$^{\circ}C$ and 15$^{\circ}C$, respectively.

• Research in Plant Disease
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• v.22 no.2
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• pp.65-71
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• 2016

Cymbidium mosaic virus (CymMV) is a major virus infecting orchid plants and causing economic loss. In this study, the incidence of viral infection in Calanthe spp. at the Korean Institute of Calanthe was investigated using reverse transcription polymerase chain reaction. The CymMV infection rate was 42%, and the two viruses Odontoglossum ringspot virus and Cucumber mosaic virus had frequencies of 8% and 2%, respectively. Additionally, we characterized an isolate of CymMV, CymMV-GW, using biological tests and examined the nucleotide sequence properties of its complete genome. CymMV-GW induced chlorotic ringspots and chlorotic spot symptoms in inoculated leaves of Chenopodium amaranticolor and Nicotiana benthamiana, respectively. In this study, we have for the first complete genome sequence of CymMV-GW in Korea. The CymMV-GW genome was 6,225 nucleotides in length, excluding the poly-(A) tail, and showed whole-genome nucleotide and amino acid sequence identities of 97.7% and 100%, respectively, with the NJ-1 isolate of CymMV. Here, we report the complete genome sequence of the CymMV-GW isolate and viral infection rates for Calanthe spp. in Korea.

• Korean Journal of Environmental Agriculture
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• v.25 no.1
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• pp.93-103
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• 2006

This study was undertaken to survey the usage of environment-friendly materials for 8 vegetable crops including cucumber, tomato, strawberry, eggplant hot pepper, lettuce, perilla leaves, and Welsh onion, cultivated under protected houses. Total of 78 environment-friendly growers in the Southern part of Korea were surveyed from 2003 to 2004. The number of materials used for a crop based on the effectiveness claimed by farmers was $21{\sim}87$ for pest control, $0{\sim}9$ for fertilizing, $2{\sim}41$ for growth promotion and $10{\sim}37$ for soil improvement. It is needed to clarify the ingredients and effectiveness of those environment-friendly materials reaching 323 items, on a science-basis in the future.

• Plant Disease and Agriculture
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• v.5 no.1
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• pp.20-26
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• 1999

Ultraviolet light is required for the sporulation of Didymella bryoniae, a gummy stem blight fungus in cucurbits such as watermelon, melon, oriental melon, cucumber and pumpkin. In this experiment, the upper limit of wave length for the production of pycnidia of D. bryoniae was 365 nm - 375 nm. Two plastic houses were covered with either common transparent film (wave length longer than 225 nm is transmitted) or UV-absorbing film ( wave lenght shorter than 388 nm is absorbed). In both houses, seedlings inoculated with D. bryoniae were placed in the center of the house at 30 days after transplantation of watermelon (cv. Whanhoseong), and the disease incidences between the houses were compared until 80 days after transplantation. The number of disease lesions and incidence of pycnidia-producing lesions under the UV-absorbing film were reduced by 90% and 80%, respectively, compared to the common transparent film. The internode lengths of plants grown in the two houses were not significantly different, but the plants grown under the UV-absorbing film had longer vines and more leaves than plants under the common transparent film. However, fruit characters such as weight, length, width, rind thick and brix, were not different between the two houses. Occurrence of aphids was reduced in the UV-absorbing film, but those of mites or diseases (powdery mildew and sooty mold) were not different between the houses. These results suggest that disease incidence of gummy stem blight of watermelon in the greenhouse can be controlled by the use of UV-absorbing film.