• The Plant Pathology Journal
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• v.15 no.1
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• pp.8-13
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• 1999

Hypersensitive cell death of plants during incompatible plant-pathogen interactions is one of the efficient defense mechanisms of plants against pathogen infections. For better understanding of the molecular mechanisms involved in the plant hypersensitive response (HR), TMV-induced biotic plant cell death and CuSO4-induced abiotic plant cell death were compared in terms of expression patterns of ten different defense-related genes as molecular markers. The genes include five pathogenesis-related protein genes, two plant secondary metabolite-associated genes, two oxidative stress-related genes and one wound-inducible gene isolated from tobacco. Northern blot analyses revealed that a same set of defense-related genes was induced during both biotic and abiotic cell death but with different time and magnitude. The expression of defense-related genes in tobacco plants was temporarily coincided with the time of cell death. However, when suspension cell cultures was used to monitor the expression of defense-related genes, different patterns of the gene expression were detected. This result implies that three are common and, in addition, also different branches of signaling pathways leading to the induced expression of defense-related genes in tobacco during the pathogen- and heavy metal-induced cell death.

• Korean Journal of Environmental Agriculture
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• v.6 no.1
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• pp.67-75
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• 1987

The major objectives of this study were to find out the growth and yield of two ecotypes of Korean garlic in main garlic producing districts in Korea. The data were collected by the field survey which had been conducted at 270 township in 58 major garlic production countries throughout the country on 10th, 20th, and 30th day of every month from 1982 to 1984. The results of this study were as follow: 1) Sowing period of garlic of southern and northern ecotype were around September 20 and October 20, respectively. 2) Average number of plants per $3.3m^2$ of the southern and northern ecotype were 123 and 100, respectively. 3) Leaf emergence time of southern ecotype was before the beginning of winter (November) and that of northern ecotype was from early February till April. 4) Stepwise multiple regression analysis showed that the plant heights measured on November 30 for southern ecotype and on June 30 for northern ecotype most adequately predicted the yield of garlic. The relationship between yield and plant height were as follows: Southern ecotype; Y=571.56+5.34X Northern ecotype; Y=251.81+5.45X where Y is yield expressed in Kg/l0a and X is height in cm at the respective date. 5) The number of leaves increased until harvest in both ecotypes. At harvest, the number of leaves in southern and northern ecotype were 10 and 8, respectively. Number of leaves counted on January 20 for southern ecotype and on June 20 for northern ecotype correlated best with the yield of the ecotypes. 6) The highest senescent portion of southern ecotype and northern ecotype were seen on January 30 and May 30, respectively. Stepwise multiple regression analysis showed that the senescent portion of southern ecotype counted on January 30 and that of northern ecotype on June 20 mostly affected the yield. 7) Average yield of southern and northern ecotype at the main garlic producing districts were 771 and 652Kg/10a, respectively.

• Research in Plant Disease
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• v.17 no.2
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• pp.205-210
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• 2011

The disease occurrence on red-pepper plants in relation to cultivation methods of the farmers and to the precipitation was investigated in northern Kyungbuk Province. The major diseases were mosaic, anthracnose and Phytophthora blight in 2007 and 2008. In 2008, mosaic was more severe than that in 2007, but the other diseases were milder than those in 2007. A negative correlation between the mosaic incidence in the harvesting season and the precipitation during May was recognized. On the other hand, there was a positive correlation between the severity of Phytophthora blight in September and the precipitation during August. The occurrence of anthracnose, Phytophthora blight and mosaic in the surveyed pepper plants grown in plastic houses were milder than those in fields, although the farmers cultivating red-pepper plants in the plastic houses were less than 5% in the northern Kyungbuk Province.

• Journal of Plant Biology
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• v.38 no.2
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• pp.203-209
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• 1995

Tobacco (Nicotiana tahacum L. cv. Wisconsin 38) leaf discs were cocultivated with Agrohacterium carrying a leghemoglobin (Lb) cDNA from Canavalia lineata. Seven plants were regenerated from the transformed leaf discs on MS media supplemented with 0.5 mg/L BAP, 0.1 mg/L ${\alpha}-NAA$, 200 mg/L kanamycin and 500 mg/L carbenicillin. Southern hybridization and PCR of genomic DNA from transgenic plants showed that the Lb cDNA was stably integrated into the genome of the tobacco. Total RNA from the transgenic tobacco showed northern hybridization signal at 1,000 nt and PCR of the first strand cDNA synthesized from the total RNA amplified 0.5 kb Lb cDNA. Furthermore, western hybridization using a polyclonal antibody against soybean Lb showed a 15.8 kD LB-like band on SDS-PAGE of proteins from the transformed tobacco. These results demonstrated that the Lb cDNA of C. lineata was not only incorporated into the genome of tobacco, but also transcribed into mRNA and translated into Lb protein in the transformed tabacco.

• Parasites, Hosts and Diseases
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• v.52 no.1
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• pp.57-62
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• 2014

Biting midges (Culicoides: Ceratopogonidae) were collected by Mosquito Magnet$^{(R)}$ traps at the Neutral Nations Supervisory Commission (NNSC) camp and Daeseongdong village inside the demilitarized zone (DMZ) and near the military demarcation line (MDL) separating North and South Korea and at Warrior Base (US Army training site) and Tongilchon 3 km south of the DMZ in northern Gyeonggi Province, Republic of Korea (ROK), from May-October 2010-2012, to determine their seasonal distributions. A total of 18,647 Culicoides females (18,399; 98.7%) and males (248; 1.3%) comprising 16 species were collected. Overall, the most commonly collected species was Culicoides nipponensis (42.9%), followed by C. erairai (29.2%), C. punctatus (20.3%), C. arakawae (3.3%), C. pallidulus (1.8%), and C. circumscriptus (1.4%), while the remaining 10 species accounted for only 1.1% of all Culicoides spp. collected. The seasonal distribution of C. nipponensis was bimodal, with high numbers collected during May-June and again during September. C. erairai was more frequently collected during June-July, followed by sharply decreased populations from August-October. C. punctatus was collected in low numbers from May-September with high numbers collected during October. C. erairai was predominantly collected from the NNSC camp (85.1% of all C. erairai collected) located adjacent to the MDL at Panmunjeom in the northernmost part of Gyeonggi-do (Province), while other sites yielded low numbers of specimens.

• The Plant Pathology Journal
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• v.15 no.5
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• pp.270-279
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• 1999

cDNAs complementary to the 3'-terminal regions of two potyvirus genomes were cloned and sequenced. The clone G7 contains one open reading frame (ORF) of 1,338 nucleotides and a 3' untranslated region (3'-UTR) of 403 nucleotides at the 3'-end excluding the 3'end poly(A) tail. The putative viral coat protein (CP) shows 55%-92% amino acid sequence homology to those of Allium potyviruses. The genome size of the virus was analyzed to be about 9.0 kb by Northern blot analysis. Five cDNA clones were screened out using GPV2 oligonucleotide as a probe. One of these clones, DEA72, which has a longest cDNA insert, contains one ORF of 1,459 nucleotides and a 3'-UTR of 590 nucleotides at the 3'-end excluding the 3'-end poly(A) tail. The putative viral CP shows 57%-88% amino acid sequence homologies to those of Allium potyviruses. The genome size of the virus was analyzed to be about 9.6 kb by Northern blot analysis. The results of immunoblot and Northern blot analyses suggest that almost all of the tested garlic plants showing mosaic or streak symptoms are infected with DEA72-potyvirus in variable degrees but rarely infected with G7-potyvirus in variable degrees but rarely infected with DEA72-potyvirus in variable degrees but rarely infected with G7-potyvirus. Immunoelectron microscopy using anti-DEA72 CP antibody shows that this potyvirus is about 750 nm long and flexuous rod shaped.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.112.2-112
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• 2003

Levels of blister rust infection (from Cronartium ribicola) varied in western white pine(Pinus monticola Dougl.) seedlings grown in two nurseries in northern Idaho. This observation suggested the potential importance of environmental components operating on the blister rust pathosystem. In an experiment designed to test the influence of environmental conditions at two nurseries, seedlings of a single genetic source were unintentionally held in cold storage for 6 months longer at one nursery than at the other. Subsequently, these seedlings, which had been growing under nursery conditions for 7 months or 1 month, were inoculated with blister rust spores on September 9th, 1999. Infection efficiency measured on the seedlings with only 1 month of growth was 70X greater than on the seedlings that had 7 months for their new growth to mature. Results from this nursery test and infection levels of northern Idaho resistant selections in mild climates suggest that expression of genes related to rust resistance in western white pine can be manipulated by regulation of phonology. If so, several new molecular tools may be employed to enhance our understanding of environmental regulation of genes for blister rust resistance.

• Research in Plant Disease
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• v.21 no.4
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• pp.261-267
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• 2015

During the period from 2013 to 2014, disease occurrences by various pathogens in apple cultivars have been investigated in northern Gyeongbuk province of Korea. Anthracnose, white rot, Alternaria leaf spot, Marssonina blotch, and bacterial shoot blight as major diseases have been observed. Pathogens isolated from the symptomatic plants were identified as Colletotrichum gloeosporioides for anthracnose, Botryosphaeria dothidea for white rot, Alternaria alternata for Alternaria leaf spot, Marssonina mali for Marssonina blotch, and Pseudomonas syringae pv. syringae for bacterial shoot blight. Of all diseases, the bacterial shoot blight has been severely increased in chronically infested fields in Gyeongbuk province.

• Korean Journal of Plant Taxonomy
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• v.41 no.3
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• pp.182-193
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• 2011

As a part of the on-going effort to conserve endangered Scrophularia takesimensis Nakai in Korea, its genetic structure and diversity from 3 population, consisted of 14 subpopulations in Ulleung Island were analyzed using RAPD band patterns. Out of 60 primers tested, 33 generated amplified bands with its genome, including 149 polymorphic and 67 monomorphic bands. The highest number (146) was found in northern population, especially, 64 in HY subpopulation; the smallest (40) in eastern population. An examination of its genetic structure with AMOVA revealed that about 60% of all variations could be assigned to among subpopulations within populations. Population differentiation among populations and subpopulations is seriously going now because of habitat fragmentation due to human activities, such as road and small port construction. Although the habitats of S. takesimensis in Ulleung Island, Korea are disappeared at an alarming rate, significant levels of genetic variation still exist at species level, and population level, especially northern population. Therefore, three conservation strategies should be needed urgently; 1) preservation of populations as it stands, 2) establishment of recovery plan to connect population and subpopulations genetically, and 3) long-term monitoring.

• Korean Journal of Plant Tissue Culture
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• v.21 no.2
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• pp.111-115
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• 1994

Two different gravity specific cDNA, namely, GSC 13 and GSC 124 with length of 1.34 and 0.67 kilobase pairs, and transcripts of 2.0 and 1.9 kilobase pairs, respectively. were isolated by differential screening and northern hybridization of the total RNA isolated from treated and untreated cultured cells showed that maximum levels of trannscripts were achieved after 4 h of gravity stress at 450, 000 x g for both, GSC 13 and GSC 124, suggesting that these mRNA could be expressed and translated into polyeptites related to the cell to extream gravity stress.