• Korean Journal of Microbiology
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• v.4 no.2
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• pp.5-10
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• 1966

The relationships between tumor score and peroxidase activities of tomato stems infected with Agrobacterium tumefaciens strain A6Kl, B6, T372 11BNV6, 11BV7 and wounded stem as a control were examined in relation to crown gall tumor development on purpose to study the lignification of tumor tissue which is affected to the development of crown gall tumor. As the previous paper has been mentioned the fact that the induction of tumor tissues were inhibited or limited in the lignified stem of host plant. It was presumed that the activities of peroxidase related to the development of lignification were decreased during the period of tumor development. But the experimental result in this experiment shows that the peroxidase activities of crown gall tumor-tissues infected with the A. tumefaciens strains which are already known as virulent are increasing during four weeks, however, in the strain 11BNV6 and wound the peroxidase activities are decreasing on the second week after the inoculation of the bacteria strains. These results could be explained on the basis of that possible regulatory agents of lignification which were accumulated in tumor tissues, IAA, ascorbic acid, glutathion(GSH) and caffeic acid esters, were postulated to act as antioxidants which has been suggested by Stafford. Total nitrogen contents in relation to crown gall tumor development were determined for the detection of protein synthesis related to the enzyme activities which are increasing in the time of plant growth. Generally six groups are contained the largest amount of nitrogen on the second week after the inoculation of the bacterium. Comparing to the tumor score, it is presumed that the all of enzyme activities including peroxidase in tumor tissues are increasing from the second week through the third week after the inoculation of bacterium and the protein synthesis is stimulated under the most appropriated temperature during the above periods.

• Korean Journal of Plant Tissue Culture
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• v.26 no.1
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• pp.31-35
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• 1999

Morphological characteristic during formation of tobacco crown gall tumor and genetic tumor, and their differential response to growth regulator were investigated in in vitro culture. Crown gall tumor was induced from tumor tissue transformed by infecting Agrobacterium tumefaciens C58. Genetic tumor was induced from tumor tissue which was induced spontaneously from reciprocal interspecific hybrids between Nicotiana glauca (2n=24) and Nicotiana langsdorffii (2n=18). Morphological characteristic of crown gall tumor, genetic tumor, and teratoma shoot was very similar, and they were actively proliferated on hormone-free medium. Typical tumor callus and teratoma shoot formed from crown gall tumor on the hormone-free medium. On the contrary, tumor callus derived from genetic tumor formed as a crown gall tumor callus on the medium supplemented with 0.5 mg/L of 2,4-D, and lots of teratoma shoots without any root formed on the hormone-free medium. Root development from the teratoma shoots was hardly obtained on the medium with IAA, GA and active carbon. However, teratoma shoots with roots, as normal shoots, were initiated occasionally on the hormone-free medium. These shoots also formed new genetic tumor on the stem, which leaves formed lots of teratoma shoot on the hormone-free medium in in vitro culture.

• Korean Journal of Agricultural Science
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• v.47 no.3
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• pp.693-705
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• 2020

Grapes (Vitis spp. L.) are the third most produced fruit in the world. Crown gall disease caused by Agrobacterium vitis forms galls in the stems of the grapevines and reduces the vitality of the fruit trees, resulting in reduced yields. This pathogen has occurred in vineyards worldwide and caused serious economic losses. It is a soil-borne disease, so Agrobacterium vitis can survive for several years in vineyards and is difficult to control. Additionally, since there is no effective chemical control method, the most effective control method is the breeding of resistant varieties. To make the resistant variety, marker-assisted selection (MAS) enables fast breeding with low cost. In this study, we applied a genome-wide association study (GWAS), by combining phenotyping and genotyping-by-sequencing (GBS), for the development of a single nucleotide polymorphism (SNP) marker set related to crown gall disease using 350 grapevine varieties. As a result of the GBS based genotyping analysis, about 58,635 SNPs were obtained. In addition, the phenotypic analysis showed 35.2% resistance, 73% moderate susceptibility and 16.4% highly susceptibility. Moreover, after confirmation, two genes (VvARF4 and VvATL6-like) were shown to be related to crown gall disease based on the results of GWAS analysis, using the phenotypic data, and GBS. High-resolution melting analysis (HRMA) was performed using the Luna^® Universal Probe with real-time PCR to distinguish the melting peaks of the resistant and susceptible varieties. Our data show that these SNP markers are expected to be helpful in evaluating resistance against grapevine crown gall disease and in breeding.

• Research in Plant Disease
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• v.6 no.1
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• pp.23-26
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• 2000

Effects of infection time of the clubroot pathogen, Plasmodiophora brassicae, on yield loss of Spring-sown Chinese cabbage plants were examined in field experiments. Yield loss of Chinese cabbage plants increased as the infection time becomes early. Plants infected at 20 days after transplanting or earlier were completely killed before harvest, and those infected at 30 days after transplanting were healthy in appearance but their head weights were reduced to 59% with poor commodity value. The plants infected 40 days after transplanting were not affected in yield. Development of root hairs in diseased plants was greatly reduced as the infection progressed, and root length was reduced to 1/2 to 1/3 of that of healthy plants. root galls were first developed 20 days after inoculation and rapidly enlarged to reach the peak in size 20 days from initial development, and decayed thereafter. Development and decay of root galls tended to be faster at later season as air temperature became high, regardless of the infection time. Diseased plants started to wilt approximately 10 days after root gall development. Root galls began to decay 10 days after initial plant wilting, and then were completely rotten within following 10 days. Based on the results, root gall development stages on spring-sown Chinese cabbage plants could be grouped into 20 days of root gall enlargement period, and 10 days of root gall decay period, followed by survival period in soil.

• Korean Journal of Oriental Medicine
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• v.3 no.1
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• pp.153-167
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• 1997

Conventionally, identification and classification methods of natural products include the morphological survey and assay of chemical disposition, sing these methods, however, is not satisfying for the precise identification of natural products because they are often valiable in the compositions and morphology To standardize the natural products identification and classification, genomic DNA analysis such as RAPD, RFLP and Amp-FLP can be adopted for this purpose. In this study, various ginsengs and bear gall bladder were tested for the development of genetic identification and classification method. Varieties of ginsengs such as, P. ginseng, P. quinquefolium, P. japonicus and P. notoginseng, were genetically analyzed by RAPD. Also, DNA isolated from Bear blood and gall bladder, Ursus thibetanus, Ursus americanus and Ursus arctos, were analyzed by the same method. The results demonstrated that the identification and classification of bear gall bladder and various ginsengs were possible by RAPD analysis. Therefore, this method was thought to be used as a additional method for the identification and classification of other natural products.

• The Korean Journal of Zoology
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• v.8 no.2
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• pp.15-18
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• 1965

Fatty acid components of the Chestnut gall wasp (Dryocosmus kuriphilus YASUMATSU) were analyzed by the method of gas chromatogrphy at various developmental stages. 1. The fatty acids identified at each stage are as follows : Larva stage : acetic acid , benzoic acid and capric acid. Prepupa stage : acetic acid, benzoic acid and capric acid. Pupa stage : acetic acid, benzoic acid and capric acid. 2. Through the development of the wasp, there were large amount of acetic acid.

• Korean journal of applied entomology
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• v.21 no.3 s.52
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• pp.163-166
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• 1982

The pine needle gall midge, Therodiplosis japonensis Uchida et Inouye, is the most important insect pest. It requires two different habitats for the development; on trees and under the ground. The habitat specific mortality rates ere $30\~40\%,\;and\;50\~60\%$ for the respective habitats. The key developmental stage is the prepupa, and the key mortality factor is the moisture contents of the soil and its variability. Since the insect is an exotic, the population status is the periphery and in the source of infestation are considerably different. Such a difference in habitats and the population status of the insect should be considered in relation to suppression of the insect. The control strategies should be directional and rational based on the reality of the pest status. There have been substantial information on the control methods of the pine needle gall midge, and each control method has an important place, but none has always provided a satisfactory solution to the many problems associated by this insect. These methods should be applied to a system based on the ecology of the insect. There should be continued support for directed effort on the development of operational management systems for the insect: specifically, estmation of the critical economic injury level, and of the absolute density of the insect.

• The Korean Journal of Ecology
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• v.1 no.2
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• pp.66-71
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• 1977

The growth of red and black pines in Muan, Seochen, Gapyeong and Kochang areas was compared by means of the growth of annual ring width and stem analysis to study the process of damages caused by pine needle gall midge. Red pine forest of Seocheon area began to suffer by pine needle gall midge from 1961 and the damage was to becoming severe from 1967. The damage became so intense tha tmany forests are withering to death from spring of 1975. Black pine forest also began to suffer from 1973. Red pine forest of Muan area was supposed to be suffered from 1973. Red pine forest of Kochang area suffered by pine needle gall midge from 1967. It seems that the damage became severe from 1973 and that black pine forest was also badly damaged from that time. Red pine forest of the control plot, Gapyeong area, began to suffer from 1967 and it also became intense from 1973. Although the areas of Seocheon, Muan, Kochang, and Gapyeong are different from each other in terms of locality and the infitration period of pine needle gall equally from 1967 due to mass development of population or other factors and the damage became more intense from 1973. Black pine forest was also badly damaged from that time. Black pine seems to be stronger in insect resistant than red pine. This can be justified by the fact that it began to suffer belatedly in each area and the degree of damage is moderate. The damage of Seocheon area is the severest following Kochang. Muan area is relatively moderate but the forest becoming decrease in growth.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.393-398
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• 2020

The blueberry gall midge, Dasineura oxycoccana (Johnson) (Diptera: Cecidomyiidae), is an emerging pest on cultivated blueberries in Korea. To develop a sensitive tool for monitoring this pest in blueberry orchards, we compared the attractiveness of host plant volatiles and sex pheromone to D. oxycoccana adults. We performed gas chromatography-mass spectrometry (GC-MS) analysis of solid-phase microextraction (SPME)-collected volatiles that were released from blueberry ('Darrow' cultivar). The analysis revealed two major volatiles, cinnamaldehyde and cinnamyl alcohol from flowers; and three major volatiles, β-caryophyllene, germacrene D, and α-farnesene from shoots and young fruits. In field tests conducted in Gunsan, Korea in 2019, commercialized cinnamaldehyde, cinnamyl alcohol, β-caryophyllene, and α-farnesene, used singly or in quaternary combination, were unattractive to the blueberry gall midge. However, traps baited with the known sex pheromone (2R,14R)-2,14-diacetoxyheptadecane attracted significantly more males than the treatments with plant volatiles or the control. No synergistic effect was observed between sex pheromone and plant volatiles. Male D. oxycoccana were captured in the pheromone traps from May to August, with three peaks in mid-May, late June, and late July in Gunsan blueberry fields in 2020.

• 한국균학회소식:학술대회논문집
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• 2015.05a
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• pp.27-27
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• 2015

Clubroot (Plasmodiophora brassicae) is a serious agricultural problem affecting Brassica crop production worldwide. It also infects the model plant Arabidopsis thaliana. During infection, this biotrophic pathogen manipulates the development and metabolism of its host leading to the development of galls in the root and hypocotyl. In turn, its own development is strongly influenced by the host. The aim of this study is to investigate the metabolism of clubroot-infected plants using a combination of transcriptomic and metabolomic approaches. We have used direct injection mass spectrometry to obtain a metabolic fingerprint of when changes in the metabolome occur and linked this with changes in host and pathogen gene expression. We have identified alterations in carbohydrate metabolism that occur during P. brassicae infection of A. thaliana plants. Transcriptomic analysis showed that host genes associated with sugar transport and metabolism were induced during gall formation and that the pathogen also expresses genes associated with these processes. We have examined the impact of inactivating host sucrose synthase, cytosolic invertase and sugar permeases on gall formation, identifying host genes that are required for gall formation. We have also explored how sugar status is changed in root tissue, developing and mature leaf during infection of wild type and mutant plants.