• Research in Plant Disease
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• v.17 no.3
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• pp.402-404
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• 2011

The Sclerotium blight was found on Phalaenopsis spp. at Dong-du-cheon city, and Hwa-seong city, Gyenggido, Korea in September 2009. The symptom included yellowing on lower leaves and wilt of a whole plant. Severely infected plants were blighted and died eventually. White mycelial mats appeared on the surface of basal stem and bulbs and the sclerotia were formed on stems, roots, and sphagnum moss. The sclerotia were spherical, 1-3 mm and white to brown. The optimum temperature for the growth and sclerotia formation was $25-30^{\circ}C$ on PDA. On the pathogenicity test, the first symptom appeared 5 days after inoculation and developed to severe stem rot and blight. On the basis of mycological characteristics and pathogenicity, the causal fungus was identified as Sclerotium rolfsii. This is the first report on the sclerotium blight on Phalaenopsis spp. caused by Sclerotium rolfsii in Korea.

• Journal of Plant Biotechnology
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• v.43 no.4
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• pp.417-421
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• 2016

The complete chloroplast genome sequence of Panax ginseng breeding line 'G07006', showing higher salt tolerance, was confirmed by de novo assembly using whole genome next-generation sequences. The complete chloroplast (CP) genome size is 156,356 bp, including two inverted repeats (IRs) of 52,060 bp, separated by the large single-copy (LSC 86,174 bp) and the small single-copy (SSC 18,122 bp) regions. One hundred fourteen genes were annotated, including 80 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. Among them, 18 sites were duplicated in the inverted repeat regions. By comparative analyses of the previously identified CP genome sequences of nine cultivars of P. ginseng and that of G07006, five useful SNPs were defined in this study. Since three of the five SNPs were cultivar-specific to Chunpoong and Sunhyang, they could be easily used for distinguishing from other ginseng accessions. However, on arranging SNPs according to their gene location, the G07006 genotype was 'GTGGA', which was distinct from other accessions. This complete chloroplast DNA sequence could be conducive to discrimination of the line G07006 (salt-tolerant) and further enhancement of the genetic improvement program for this important medicinal plant.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.413-422
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• 1993

Air shipment affords the quickest possible delivery of horticultural products. The price of air shipped horticultural products are relatively high as most of these products are perishable. Usually the temperature in the cargo compartment is not controlled during flight. Thus, special attention should be paid to procooling prior to shipment. The environmental condition during transportation of horticultural products is an essential parameter for maintaining the quality of perishable products. Commonly horticultural products were loaded by ULD(Unit Load Devices) as a container or pallet in the aircraft (except for small aircraft) . Therefore, inside temperature of the container and cargo compartment came into question. Scarce literature on the relationship between environmental condition and quality changes of horticultural products during air shipment can be found. By the stand point of keeping fresh quality, investigations on the actual condition of air shipments were carried out to improve the technique during the distribution process of fresh horticultural products. Temperature, humidity, atmospheric pressure, carbon dioxide, ethylene, impacts, and changes in quality during the air shipment of snapbeans, okras and chrysanthemums were measured. Temperature was measured by recording thermometers, relative humidity by recording hygrometers, atmospheric pressure by a strain -guage type pressure sensor, carbon dioxide by testing tubes, ethylene by sampling bags and a gaschromatograph, impacts and vibrations by impact recorders and a 3D accelerometer. Relationships between environmental conditions and quality changes during air shipments were clarified. It was expected from investigations into actual shipments that the ventilation and insulation properties of air freight containers were related to the quality of agricultural products. Aircraft can no directly load and unload trucks into them. The transshipment is inclined to cause shocks and vibrations, and to invite damages within a short time.

• Korean Journal of Environmental Agriculture
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• v.37 no.1
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• pp.9-14
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• 2018

BACKGROUND: The use of green manure and compost as organic fertilizer may increase crop yield and soil fertility due to improved soil nutrient availability and soil organic matter content (SOM). This study aimed to investigate the effects of hairy vetch (Vicia villosa L.) and compost application on red pepper growth, yield, fruit quality and soil health. METHODS AND RESULTS: The treatments were no fertilizer (CON), chemical fertilizer (CF), hairy vetch (HV), and livestock compost+HV (LC+HV). Red pepper seedlings (70 days old) were transplanted and maintained in experimental plots for 140 days. Plant dry weight, micro- and macronutrient contents of plants and soil chemical properties were determined. All fertilizer treatments significantly increased plant dry weight. Fruit yield was significantly highest with HV treatment. As for nutrient content, plants in HV and LC+HV treatments have significantly higher K and Ca contents than the other treatments. Regarding soil properties, HV and LC+HV application significantly altered the soil chemical properties. Significantly higher SOM was observed in HV and LC+HV treated soils. CONCLUSION: The results of this study suggest that short-term application of hairy vetch and compost is an effective alternative to the conventional chemical fertilizer to increase fruit yield red pepper and improve soil health.

• Research in Plant Disease
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• v.12 no.3
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• pp.267-271
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• 2006

Botrytis cinerea Pers. was found to be highly virulent to the grapevine plant, especially in greenhouse condition. Pseudomonas species play key roles for the biocontrol of many plant diseases especially in soil. Of the 83 isolates of Pseudomonas spp., a bacterial strain P84, isolated from tomato rhizosphere, was shown to suppress a wide range of phytopathogenic fungi in vitro. The isolate was identified as Pseudomonas putida on the basis of its bacteriological and genetic characteristics. The P. putida P84 strain carry the phlD gene for 2,4-diacetylphloroglucinol biosynthesis and may produce the antibiotics as an antagonistic mechanism involved in biocontrol. The antagonistic activity of the bacterium has a promising implication for its use as a biocontrol agent to control grapevine gray mold.

• The Korean Journal of Pesticide Science
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• v.15 no.3
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• pp.298-302
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• 2011

Bacterial wilt, caused by Ralstonia, solanacearum, is a very destructive disease to tomato plants (Solanum lycopersicum) in Korea. This study was undertaken to find out the growth inhibitory effect bactericides on bacterial wilt pathogen of streptomycin, oxytetracyclin streptomycin sulfate WP and significantly suppressed the growth of bacterial wilt pathogen. Copper hydroxide WP showed control value of 62.5%. Therefore, it is concluded that the bactericide used in this study showed strong inhibitory effect to tomato bacterial wilt and they can be recommend to control the disease. And also, Copper hydroxide WP may be effective for control of bacterial wilt of tomato in conventional culture, farming without agricultural and organic farming.

• Research in Plant Disease
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• v.11 no.2
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• pp.106-114
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• 2005

To breed powdery mildew resistant varieties, 104 accessions of Cucurbita spp. germplasm were evaluated. Powdery mildew resistance and horticultural characteristics of the accessions were investigated in the field conditions. C. martinezii was selected for high resistance to powdery mildew in the field. The growth of powdery mildew pathogen and response of leaf surface tissue to the pathogen were observed after artificial inoculation to resistant C martinezii and susceptible C. moschata cv. 'Wonye No.402'. Mycelium growth was very clearly different between resistant C. martinezii and susceptible C moschata cv. 'Wonye No. 402' at 5 days after inoculation at the adult stage. Interspecific hybridization was attempted to transfer powdery mildew resistance gene(s) from C. martinezii to C. moschata. A single dominant gene action was postulated as deter mining powdery mildew resistance at the seedling stage. But for the effective selection of powdery mildew resistant individuals, it was established that adult plant resistance should be confirmed in the field conditions after the seedling test. Through the seedling and field tests, C. moschata lines resistant to powdery mildew and superior to horticultural characteristics, were selected after 2 backcrossing and 3 selfing generations. The fruit characteristics of newly developed lines were similar to those of the recurrent parent, 'Jaechenjarae'.

• Research in Plant Disease
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• v.13 no.1
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• pp.24-29
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• 2007

A total of 35 strains of Ralstonia solanacearum isolated from wilted pepper and tomato plants in Korea were analyzed for their genetic diversity by bacteriological, pathological and molecular biological approaches. All the strains were identified as R. solanacearum biovar 4 on the basis of physiological and biochemical tests, and species-specific PCR primers. Pathogenicity of the strains was confirmed by inoculating on 4-week-old pepper and tomato seedlings. Using cluster analysis based on repetitive sequence-based polymerase chain reaction (rep-PCR) genomic fingerprints, R. solanacearum strains isolated from pepper and tomato in Korea divided into 6 groups showing a high degree of genetic diversity at 55% similarity level. The genetic diversify of strains was not significantly correlated with their geographic origins and host plants.

• Research in Plant Disease
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• v.13 no.2
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• pp.82-87
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• 2007

The genetic diagnostic method of virion capture (VC)/RT-PCR was developed for the simultaneous detection of three rod shaped viruses of Cucumber green mottle mosaic virus (CGMMV), Kyuri green mottle mosaic virus(KGMMV) and Zucchini green mottle mosaic virus (ZGMMV) transmitted by seed in Cucurbit. Out of 12 primer combinations for the three tobamoviruses, a primer set of CGMMV-C724, KGMMV-K513 and ZGMMV-Z407A was useful for mono and triplex VC/RT-PCR. The triplex VC/RT-PCR for the three tobamovirus in Cucurbit could detect specifically without interference among primers and/or plant species of watermelon, gourd, cucumber, melon, pumpkin, squash and Nicotiana benthamiana.

• Research in Plant Disease
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• v.13 no.2
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• pp.126-129
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• 2007

Sooty leaf blight disease of Cymbium spp. was observed on orchid fields located at Gyeonggi-do in 2005-2006. Symptoms of the disease appeared on leaves and leaf spots were circular to nearly-circular, these circular blemished were yellow, with greater amounts of brown to black flecks forming as the spots enlarge. Severely infected leaves were dry and defoliated. These symptoms were realized wrongly as symptoms by virus. But Pseudocercospora cymbidiicola were isolated from the diseased plants. Conidiophores were produced on the lesion surface of the leaf with the blemished areas andconidia formed dark brown, cylindrical and straight to slightly curved, 5-9 septate, $23.7-85.0\;{\times}\;2.0-3.4\;{\mu}m$. Mycelial growth was mostly slow on potato dextrose agar and the optimum temperature for growth was $25^{\circ}C$. We were identified as Pseudocercoepora cymbidiicola based on the morphological characteristics.