• Korean journal of applied entomology
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• v.1
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• pp.37-41
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• 1962

Fifty three varieties of potatoes were planted at Alpine Potato Research station at Takwalyong Kangwando Province since in 1962. The varieties planted were introduced front Japan, the United States and Germany. The varietal reaction was divided into five classes, and the results were following. Immune : Kennebec, Isola, Cherokee, Merrimack, Yoraku, Lisili. Cosima. Highly Resistant : Antze, Ragis Isola, Hessenkrone, Plymouth, Sebago, Pungo, Sieglinde, Anco, Essex. Resistant : Tawa, B-605-10, Sequoia, Grata, Concordia, Onaway, Holing 1. Nisego. Susceptible: Nordak, Pontiac, Benimaru, Early Gem, Chippewa, Chitose, Ohjiro, Red Bake, Norland, Katahdin. Highly Susceptible: Russet Burbunk, May Queen, Earlaine, Irish Cobbler, Feldeslohn, Red Warba, Chisago, Osseo, Paunee. Warba, Norgleam, Red Beauty, Red Burt, Danshaku, Namchak (Native variety), In general the verieties introduced from the United States and Germany were more resistant to late blight than those introduced from Japan. Especially the German varieties were immune or highly resistant to the disease except Feldeslohn. Early maturing varieties were more susceptible to late blight than the late maturing varieties in southern Korea.

• Research in Plant Disease
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• v.13 no.1
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• pp.20-23
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• 2007

We investigated the first symptom emerging date of rice bacterial leaf blight disease during four years from 2002 to 2005. The disease occurrence date was earlier 20$\sim$30 days in 2005 than that of 2002. The damage in different rice growth stage by the bacterial disease on rice yield and grain quality in southern part of Korea was examined. The disease decreased rice yield following by increased infection rates. Slight loss in rice yield and brown head rice rate were observed at below 10% level of infected leaf area, while over 25% infected leaf area caused the significant decrease in rice yield and brown head rice rate. More than 50% of the infected leaf area rate caused 29% yield reduction in case of infection at panicle formation stage and 18% of brown head rice rate. Cooked rice quality was also affected in the diseased rice by damage in palatability score and viscosity.

• Research in Plant Disease
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• v.13 no.2
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• pp.88-92
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• 2007

A total of 41 Pseudomonas syringae pv. syringae, the causal agent of bacterial blossom blight, were isolated from kiwifruit plants in Korea. Among them, two strains showing streptomycin resistance were examined to investigate the structure of resistant determinants by PCR and nucleotide sequence analysis. PCR results suggested that the streptomycin resistance is mediated by strA-strB genes carried on Tn5393a. Insertion sequences, IS6100 and IS1133, which were located within or downstream of tnpR gene in Xanthomonas campestris and Erwinia amylovora were not found. Nucleotide sequences of strA-strB were 100% identical with Tn5393a. Two stretomycin resistant strains had three plasmids. Southern blot hybridization using strA-strB probe indicated that the resistant genes were carried on a 100kb plasmid.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.6
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• pp.419-423
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• 2003

Bacterial blight caused by Xantomonas oryzae pv. oryzae is one of the most serious diseases of rice especially in southern area of Korea. Three races, $\textrm{K}_1$, $\textrm{K}_2$ and $\textrm{K}_3$, are the most dominant species. lo improve rice breeding efficiency using marker assisted selection, some RFLP markers were surveyed for polymorphism between resistant and susceptible to $\textrm{K}_1$ and $\textrm{K}_3$. And, 127 doubled-haploid (DH) lines derived from Milyang121/HRl1650-1-4-2 and 131 DH lines derived from Milyang123/HR10624-AC5 were evaluated to bacterial blight ($\textrm{K}_1$ and $\textrm{K}_3$). Milyang121 and HR10624-AC5 have Xa-1, resistant to $\textrm{K}_1$ race, and Milyang123 has Xa-3, resistant to $\textrm{K}_1$ and $\textrm{K}_3$ race. Three markers, RZ590, RZ536 and RG303, showing polymorphism between parents and resistance gene, Xa-1 and Xa-3, were analysed in the two combinations of DH lines. The segregation pattern of resistant DH population of Milyang123/HR10624-AC5 to susceptible showed 3:1 and 1:1 in $\textrm{K}_1$ and $\textrm{K}_3$ race. In three RFLP markers, RZ590 was linked to Xa-1 on chromosome 4, and RZ536 and RG303 were linked to Xa-3 on chromosome 11. The map distance between Xa-1 and RZ590 was 3.1cM on chromosome 4, and Xa-3 and RZ536/RG303 were 7.6/16.0cM on chromosome 11, respectively. The results of RFLP mapping will be useful for the selection and pyramiding of bacterial blight resistant genes.

• The Korean Journal of Mycology
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• v.30 no.1
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• pp.66-72
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• 2002

To develop DNA markers for analysis of genetic characteristics of Phytophthora capsici population, randomly selected clones from HindIII-digested genomic DNA library of P. capsici 95CY3119 were surveyed by hybridizing to Southern blots of HindIII-digested total genomic DNA of P. capsici. Probe DNAs inserted into selected individual clones strongly hybridized with HindIII digests of P. capsici. Among probes examined, PC9 revealed the repetitive and highly polymorphic bands to HindIII digests of inter-and intra-field P. capsici isolates. Genetic diversity of individual isolates was also clearly revealed in cluster analysis based on its band patterns. The other probe, PC22, was hybridized only to DNA from P. capsici and this was highly repetitive. However, there was no response to other Phytophthora species and Pythium sp. These DNA probes could be used as very useful markers in analysing genetic diversity and identification for P. capsici population throughout the world.

• Korean Journal Plant Pathology
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• v.14 no.5
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• pp.502-506
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• 1998

In this study, we calculated the genetic relationships of Pestalotiopsis species collected from various places in southern part of Korea through isozyme analyses. As a result, EST showed the largest number of band, and the number of bands were ranged from 5 to 7 on the average. All the isozymes used in this study showed distinctive band patterns for each isolates. Similarities among the compared isolates ranged from 48 to 93%. Isolates SP7, SP19 and SP23 showed more than 90% similarities, and most isolates showed similarities ranging from 65 to 82%.

• Korean journal of applied entomology
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• v.23 no.3 s.60
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• pp.147-152
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• 1984

Six hundred and twenty five isolates of Xanthomonas campestris pv. oryzae, cauing bacterial leaf blight (BLB) of rice, were classified into five pathotypes during $1979\~1983$ in Korea. Among them, 483 isolates$(77.3\%)$ were classified as pathotype I, 83 $(13.3\%)$ as pathotype II, 54$(8.6\%)$ as pathotype III, 3 $(0.5\%)$ as pathotype IV and 2$(0.3\%)$ as pathotype V. Pathotype I was the most prevalent throughout the country. Pathotype III was widely distributed in the western or southern parts of Korea, particularly in Jeonnam, Chungnam and Gyeongnam provinces. One isolate of pathotype IV was found in Gyeongnam in 1980, and two isolates were found in Jeonnam in 1981. Most of the isolates were obtained from Milyang 23 varietal group, while the isolates of pathotype III were collected from Yushin and Tongil varietal group.

• The Plant Pathology Journal
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• v.38 no.5
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• pp.541-549
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• 2022

Potato late blight caused by Phytophthora infestans is a destructive disease in Korea. To elucidate the genomic variation of the mitochondrial (mt) genome, we assembled its complete mt genome and compared its sequence among different haplotypes. The mt genome sequences of four Korean P. infestans isolates were revealed by Illumina HiSeq. The size of the circular mt genome of the four major genotypes, KR_1_A1, KR_2_A2, SIB-1, and US-11, was 39,872, 39,836, 39,872, and 39,840 bp, respectively. All genotypes contained the same 61 genes in the same order, comprising two RNA-encoding genes, 16 ribosomal genes, 25 transfer RNA, 17 genes encoding electron transport and ATP synthesis, 11 open reading frames of unknown function, and one protein import-related gene, tatC. The coding region comprised 91% of the genome, and GC content was 22.3%. The haplotypes were further analyzed based on sequence polymorphism at two hypervariable regions (HVRi), carrying a 2 kb insertion/deletion sequence, and HVRii, carrying 36 bp variable number tandem repeats (VNTRs). All four genotypes carried the 2 kb insertion/deletion sequence in HVRi, whereas HVRii had two VNTRs in KR_1_A1 and SIB-1 but three VNTRs in US-11 and KR_2_A2. Minimal spanning network and phylogenetic analysis based on 5,814 bp of mtDNA sequences from five loci, KR_1_A1 and SIB-1 were classified as IIa-6 haplotype, and isolates KR_1_A2 and US-11 as haplotypes IIa-5 and IIb-2, respectively. mtDNA sequences of KR_1_A1 and SIB-1 shared 100% sequence identity, and both were 99.9% similar to those of KR_2_A2 and US-11.

• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.443-446
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• 2008

'Gangbaek' is a japonica rice variety developed and registered by the rice breeding team of Department of Rice and Winter Cereal Crop, NICS, RDA in 2006. 'Gangbaek' was derived from a cross between 'Suweon345' with good grain quality and 'DV85' resistant to bacterial blight, $K_{3a}$. $F_1$ plants were grown in the greenhouse in winter of 1992/1993 and backcrossed with 'Suweon345' as the recurrent parent. Plants resistant to $K_{3a}$ race of bacterial blight (BB) were selected from $BC_1F_1$ to $BC_4F_1$ and used as parents in the backcrossing processes. This variety has about 120 days growth duration from transplanting to harvesting in west-southern coast and Honam plain of Korea. It is about 69 cm in culm length and tolerance to lodging. In reaction to biotic and abiotic stresses, it shows moderately resistance to blast, and resistance to bacterial blight pathogen, $K_1$, $K_2$, $K_3$ and $K_{3a}$, but susceptible to other major diseases and insect pests. The milled rice of 'Gangbaek' exhibits translucent, relatively clear non-glutinous endosperm and midium short grain. It has lower amylose content of 18.6% and protein content of 6.4% compared with 'Nampyeongbyeo'. The milled rice yield performance of this variety is about 5.28 MT/ha in local adaptability test for three years. This cultivar would be adaptable to the bacterial blight-prone area in the south-western coastal and Honam plain of Korea.

• Korean Journal of Microbiology
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• v.43 no.4
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• pp.337-340
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• 2007

Pseudomonas syringae Pv. syringae is a causal agent of bacterial blossom blight of kiwifruit in Korea. Eleven strains of the pathogen were isolated from different kiwifruit orchards in Korea and the plasmid profiles were obtained by pulsed-field gel electrophoresis. They could be clustered into six groups according to the number and size of plasmids. The number of plasmids per strain and size of these plasmids ranged from 0 to 4 and from 22 to 160 kb, respectively. Among them, four strains belonging to Group III which harbored two plasmids were resistant to copper sulfate. Southern blot hybridization of the plasmid DNA indicated that the copper resistance determinant was carried on a 48 kb plasmid.