• Research in Plant Disease
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• v.18 no.4
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• pp.290-297
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• 2012

In this study, total number of 1941 Capsicum accessions conserved at RDA Genebank was evaluated for their response to Cucumber mosaic virus (CMV). These accessions were composed with 9 species originated from 89 countries, included 839 Capsicum annuum, 277 C. baccatum, 395 C. chinense, 343 C. frutescens, 49 C. pubescens, and other 38 wild pepper species (C. chacoense, C. galapagoense, etc.). Resistant to CMV was screened with the 240H02SP6 SNP marker related to the Cmr1 (Cucumber mosaic resistance 1). Eighty nine accessions of pepper germplasm were resistant to CMV based on the marker. One hundred sixty two accessions showed heterozygosity. One thousand two hundred seventy accessions were susceptible to CMV. Four hundred twenty accessions did not show distinction by 240H02SP6 marker. These 89 resistant pepper germplasm can be used in a pepper breeding program against CMV.

• Korean Journal of Microbiology
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• v.54 no.3
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• pp.188-199
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• 2018

Genomic epidemiology exploits various basic microbial research areas. High-throughput sequencing technologies dramatically have been expanding the number of microbial genome sequences available. Abundant genomic data provide an opportunity to perform strain typing more effectively, helping identify microbial species and strains at a higher resolution than ever before. Genomic epidemiology needs to find antimicrobial resistance genes in addition to standard genome annotations. Strain typing and antimicrobial resistance gene finding are static aspects of genomic epidemiology. Finding which hosts infected which other hosts requires the inference of transient transmission routes among infected hosts. The strain typing, antimicrobial resistance gene finding, and transmission tree inference would allow for better surveillance of microbial infectious diseases, which is one of the ultimate goals of genomic epidemiology. Among several high-throughput sequencing technologies, genomic epidemiology will benefit from the more portability and shorter sequencing time of the Oxford Nanopore Technologies's MinION, the third-generation sequencing technology. Here, this study reviewed computational methods for quantifying antimicrobial resistance genes and inferring disease transmission trees. In addition, the MinION's applications to genomic epidemiology were discussed.

• Korean journal of applied entomology
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• v.43 no.1
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• pp.43-48
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• 2004

Development of 3,700 folds resistance to etoxazole was found in the population of twospotted spider mite, Tetranychus urticae, collected from rose greenhouses in Buyo, Chungnam Provience in August 2000. This population was selected for 3yr with etoxazole to get 5,000,000 folds increase in resistance as compared to susceptible (S) strain. The etoxazole resistance was stablized for 16 months under the condition of no acaricide application. Inheritance and cross resistance in etoxazole to some acaricides of the etoxazole resistance strain (R) were investigated. There were differences of susceptibility in the etoxazole concentration-mortality relationships between $F_1$, $F_2$ progenies obtained from reciprocal cross with the S and R strains (R$_{♂}$${\times}$S$_{♂}$${\times}$R$_{♂}$). Degrees of dominance were 0.98 and 0.98 in $F_1$ and $F_2$ progenies of R$_{♂}$${\times}$S$_{♂}$, and -0.97 and -0.68 in $F_1$ and $F_2$ progenies of S$_{♀}$${\times}$R$_{♂}$ respectively. Inheritance in $F_1$ and $F_2$ progenies of R$_{♀}$${\times}$S$_{♂}$ were complete dominant. However $F_1$ and $F_2$ progenies of S$_{♀}$${\times}$R$_{♂}$ were incomplete recessive. These results suggest that inheritance of etoxazole resistance is controlled by a complete dominance. The R strain exhibited cross resistance to acequinocyl and emamectin benzoates in adult females, and milbemectin, amitraz and pyridaben in eggs. However they showed negatively correlated cross-resistance to bifenazate, a carbazate acaricide. These results may indicate bifenazate could be useful for the control of etoxazole resistant T. urticae population.

• Journal of Life Science
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• v.31 no.7
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• pp.609-616
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• 2021

Bacterial soft rot, caused by Pectobacterium carotovorum subsp. carotovorum (Pcc), is one of the destructive diseases of radish (Raphanus sativus) in Asian countries. The objective of this study was to establish an efficient bioassay method for the evaluation of bacterial soft rot resistance in commercial radish cultivars. First, an efficient bioassay method for examining resistance to bacterial soft rot in commercial radish cultivars was investigated. Six commercial radish cultivars were tested under various conditions: two temperatures (25℃ and 30℃), three inoculations methods (drenching, spraying, and root dipping), and two growth stages (two- and four-leaf stages). The results suggested that spraying with 1×10⁶ cfu/ml of bacterial inoculums during the four-leaf stage and incubating at 30℃ could be the most efficient screening method for bacterial soft rot resistance in commercial radish cultivars. Second, we investigated the degree of resistance of 41 commercial radish cultivars to five Pcc isolates, namely KACC 10225, KACC 10343, KACC 10421, KACC 10458, and KACC 13953. KACC 10421 had the strongest susceptibility in terms of moderately resistant disease response to bacterial soft rot. Out of the 41 radish cultivars, 13 were moderately resistant to this pathogen, whereas 28 were susceptible. The moderately resistant radish cultivars in this investigation could serve as resistance donors in the breeding of soft rot resistance or could be used to determine varietal improvement for direct use by breeders, scientists, farmers, researchers, and end customers.

• Korean Journal of Agricultural Science
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• v.3 no.1
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• pp.17-21
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• 1976

This study was conducted to determine the inheritance of resistance in some rice varieties such as WASE AIKOKU 3, ZENITH, TETEP and TKM 6 to isolate 71-23 of Xanthomonas Oryzae in Korea. From the test in $F_1$ and $F_2$ populations of crosses between resistant and susceptible parents, it was observed that resistance of them were controlled by one dominant gene.

• Current Research on Agriculture and Life Sciences
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• v.22
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• pp.13-18
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• 2004

Eighty five accessions of our laboratory pepper germplasm collections in 2003 were tested for resistance to Phytophthora capsici Leonian. Any new material highly resistant was not found among them. However, KC1184, which has horticultural characteristics of Korean peppers, was moderately resistant and appeared worthwhile in breeding for resistance.

• Korean journal of applied entomology
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• v.17 no.4 s.37
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• pp.193-199
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• 1978

Five parents and their 10 $F_1$ crosses of maize (Zea mays L.) were tested by means of diallel analysis for the inheritance of peroxidase activity following Puccinia sorghi rust infection. Peroxidase activity was measured at day zero and at 2 days and 8 days after inoculation. Peroxidase activity was increased significantly by P. sorghi infection in all 15 genotypes after 8 days, but not after 2 days. Highly significant differences in peroxidase activity were detected among the 15 genotypes. The highly genera] resistant inbred, CM105, and its hybrids showed exceptionally high peroxidase activity in both healthy and infected plants. However, another highly resistant inbred, Oh545, showed exceptionally low peroxidase activity. Significant general combining ability (GCA) and specific combining ability (SCA) means quares were detected for peroxidase activity independent of disease. GCA mean spuares, however, were consistently a major contiribution to the inheritance of peroxidase activity in the infected plants whereas SCA men square contributions were minor. Rust resistant maize plants controlling mongenic dominant $Rp_1^d$gene showed stronger peroxidase reroxidase responses than their susceptible counterparts in the gel electrophoresis and densiometric tracings. The increased peroxidase activity occurred in both major leaf peroxidases, $Px_3\;and\; Px_7$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.3
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• pp.251-255
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• 2004

The epidemics of rice blast which occurred in south parts of Korea during the period from 1999 to 2001 and damaged several high quality rice cultivars developed using "Milyang 95" and/or "Milyang 96" as a parent. Genetic diversity of 23 rice cultivars including "Milyang 95" and it's relatives was assessed using 54 simple sequence repeats (SSR) markers reported to be linked to major blast resistance genes. Fifty-four SSR markers representing fifty-seven loci in the rice genome detected polymorphism among the 23 cultivars and revealed a total of 170 alleles with an average of 3.0 alleles per primer, The number of amplified bands ranged from 1 to 7. Several SSR markers including RM249, RM206 and OSR20 were informative for assessing the genetic diversity of relatively closed japonica rice cultivars. The 23 cultivars were classified into four groups by cluster analysis based on Nei's genetic distances, and the cultivars developed from same parents showed a tendency to cluster together that is consistant with genealogical information. High quality rice cultivars, Daesanbyeo, Donganbyeo, and Milyang 95 belonged to the same cluster, At the loci, RM254 and OSR32, all of the cultivars derived from the crosses using "Milyang 95" shared same alleles, suggesting that these japonica cultivars might carry alleles that are identical by descent. Evaluation of 23 rice cultivars against blast needs to be confirmed regarding the relationship between genotype and blast resistance.p between genotype and blast resistance.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.1
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• pp.11-14
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• 1984

The inheritance of scent in rice leaf and its genetic association with base color, hull color and resistance to bacterial leaf blight were studied in F$_2$ population of two rice crosses, P-33-C-19 (scented)/Zhu-Lian-Ai and P-33-C-19/Kataktara DA2. The scent was identified by leaf analysis at tillering stage. The scented and non-scented plants segregated in the ratio of 1scented: 3non-scented showing that a recessive gene responsible for the expression of scentedness. The scentedness was independently segregated with base color. hull color and resistance to bacterial leaf blight.

• Proceedings of the KIEE Conference
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• 2008.05a
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• pp.177-178
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• 2008

오늘날 DC 케이블은 도서간의 장거리 전력전송 및 서로 다른 주파수간의 계통연계를 위해서 널리 확대되어 사용되고 있다. 일반적으로 AC케이블의 전계는 절연체의 유전율에 의해서 결정되는 용량성 전계분포를 가지며, DC케이블은 과전 초기에는 절연체의 유전율 뿐만 아니라 저항율에 의해서 결정이 되며 충분한 시간이 흐른 후에는 저항율에 의해서 결정되는 저항성 전계분포를 가진다. 본 논문에서는 해저 HVDC 케이블용 함침 절연지 절연저항의 온도 및 전계 의존성을 평가하기 위해서 저항율을 측정 하였으며 통계처리를 통해서 온도 및 전계의존성을 구하였다.