• Current Research on Agriculture and Life Sciences
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• 제32권3호
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• pp.111-117
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• 2014

고추 역병은 그 병원균의 토양전염성 때문에 약제에 의한 방제효과가 낮아 저항성 품종의 개발이 기대되어 왔다. 고추 역병에는 CM334, AC2258, PI201234 등 다수의 저항성 유전자원이 보고되었으며, 이들의 저항성의 유전에 관한 연구로 진행되었다. 그러나 저항성의 유전양식은 실험에 사용한 재료와 연구자에 따라 1개, 2개, 혹은 3개 이상의 유전자, 다수의 유전자에 의한 양적 유전 등 다양하였다. 최근에는 분자적 방법으로 양적형질유전자좌(QTL)를 구명하는 연구가 보고되고 있으며, 분자표지를 이용한 선발 기술도 이미 육종 현장에서 활용되고 있다. 최근 저항성 품종이 다수 출시됨에 따라 새로운 병원형(pathotype), 즉, 레이스(race)의 출현에 관심이 높아지면서 이에 대한 연구가 보고되고 있다. 모두 품종과 병원균주간에 특이적 변이가 있으며, 이를 토대로 몇 개의 병원형(race)으로 분류할 수 있었다. 그러나 판별품종이 통일되지 않았고 시험에 사용한 품종들의 저항성 유전자의 조성도 달라 세계적으로 통일된 레이스분류체계는 아직 없는 실정이다. 이러한 배경에서 보다 안정된 저항성 품종의 육성을 위해서는 한 가지 저항성 재료보다는 다수의 저항성 유전자원에서 저항성을 도입하고, 육성과정에 육성품종의 보급 대상지역의 여러 균주를 사용하여 선발하는 것이 필요할 것이다.

• 한국응용곤충학회지
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• 제13권1호
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• pp.11-16
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• 1974

IRRI에서 선발된 Indica형 벼, IR 667계통에서 유내한 벼 및 Japonica형 국내장려품종을 공시하여 애멸구에 대한 저항성정도를 검정하고 나아가 내충성 기작으로 간주되는 식이선호성, 산란선호성 및 항충성(Antibiosis)을 시험하여 아래와 같은 결과를 얻었다 1. IRRI에서 선발된 19개 Indica형 벼품종 중 저항성반응을 보인 것은 H 105, Muthumanikam, Vellailangalayan, Karsamba Red ASD-7, Manavari Co 22, Mudgo, PTB-18, IR-18 및 IR 20 등 9개 품종이었고 TKM-6은 중도저항성(MR)이었으며 그밖에 것은 모다 감수성으로 나타났다. 국내재료중 IR 667에서 유래한 벼는 저항성반응을 보였으나 Japonica형 5개 장려품종은 모두 감수성반응을 나타내었다. 2. 저항성품종 ASD-7과 감수성품종 Jinheung(진흥)에 대한 식이선호성은 감수성품종에서 높고 저항성품종에서 낮았는데 접종 72특간후 Jinheung과 ASD-7 두 품종에 대한 선호율은 각각 $88.6\%$와 $11.4\%$이었다. 3. 저항성품종 ASD-7과 감수성품종 Jinheung에 대한 산난선호성은 식이선호성과는 달러 저항성품종에서 높고 감수성품종에서 비교적 낮았는데 두 품종에 대한 산난비율은 저항성품종에서 $58.6\%$, 감수성품종에서 $41.4\%$이었다. 4. 저항성품종에서는 약충의 사충율이 높았고 우화율이 낮았으며 반대로감수성품종에서는 약충의 사충율이 ?았고 우화율이 비교적 높았다.저항성반응을 보인 품종종에서도 IRRI 선발품종들은 $84\%$ 이상의 사충율을 보였으나 IR 667에서 유래한 Suweon 213-1(통일품종)은 $48\%$ Suweon 214$62\%$의 비교적 낮은 사충율을 보여 저항성품종이라도 항충성정도에 차이가 있었다. 5. 이상의 결과로 보아 애멸구에 대한 저항성품종은 Indica형 벼 품종에서 상당수를 찾아 볼 수 있었으며 그들 저항성품종의 내충성 기작은 우선 비식이선호성(Non-feeding preference)과 항충성이 관계하고 산란선호성은 관계하고 있지 않은 것으로 생각되었다.

• 한국자원식물학회지
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• 제29권6호
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• pp.658-669
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• 2016

Rice blast, caused by a fungus Magnaporthe oryzae, is one of the most devastating diseases of rice worldwide. Analyzing the valuable genetic resources is important in making progress towards blast resistance. Molecular screening of major rice blast resistance (R) genes was determined in 2,509 accessions of rice germplasm from different geographic regions of Asia and Europe using PCR based markers which showed linkage to twelve major blast R genes, Pik-p, Pi39, Pit, Pik-m, Pi-d(t)2, Pii, Pib, Pik, Pita, Pita/Pita-2, Pi5, and Piz-t. Out of 2,509 accessions, only two accessions had maximum nine blast resistance genes followed by eighteen accessions each with eight R genes. The polygenic combination of three genes was possessed by maximum number of accessions (824), while among others 48 accessions possessed seven genes, 119 accessions had six genes, 267 accessions had five genes, 487 accessions had four genes, 646 accessions had two genes, and 98 accessions had single R gene. The Pik-p gene appeared to be omnipresent and was detected in all germplasm. Furthermore, principal component analysis (PCA) indicated that Pita, Pita/Pita-2, Pi-d(t)2, Pib and Pit were the major genes responsible for resistance in the germplasm. The present investigation revealed that a set of 68 elite germplasm accessions would have a competitive edge over the current resistance donors being utilized in the breeding programs. Overall, these results might be useful to identify and incorporate the resistance genes from germplasm into elite cultivars through marker assisted selection in rice breeding.

• The Plant Pathology Journal
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• 제38권1호
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• pp.1-11
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• 2022

Fusarium culmorum is one of the most important causal agents of root rot of wheat. In this study, 10 F. culmorum isolates were collected from farms located in five agro-ecological regions of Morocco. These were used to challenge 20 durum wheat genotypes via artificial inoculation of plant roots under controlled conditions. The isolate virulence was determined by three traits (roots browning index, stem browning index, and severity of root rot). An alpha-lattice design with three replicates was used, and the resulting ANOVA revealed a significant (P < 0.01) effect of isolate (I), genotype (G), and G × I interaction. A total of four response types were observed (R, MR, MS, and S) revealing that different genes in both the pathogen and the host were activated in 53% of interactions. Most genotypes were susceptible to eight or more isolates, while the Moroccan cultivar Marouan was reported resistant to three isolates and moderately resistant to three others. Similarly, the Australian breeding line SSD1479-117 was reported resistant to two isolates and moderately resistant to four others. The ICARDA elites Icaverve, Berghisyr, Berghisyr2, Amina, and Icaverve2 were identified as moderately resistant. Principal component analysis based on the genotypes responses defined two major clusters and two sub-clusters for the 10 F. culmorum isolates. Isolate Fc9 collected in Khemis Zemamra was the most virulent while isolate Fc3 collected in Haj-Kaddour was the least virulent. This work provides initial results for the discovery of differential reactions between the durum lines and isolates and the identification of novel sources of resistance.

• The Plant Pathology Journal
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• 제38권4호
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• pp.272-286
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• 2022

Black root rot (BRR) caused by Lasiodiplodia theobromae is an alarming disease of mulberry that causes tremendous economic losses to sericulture farmers in India and China. Successful control of this disease can be attained by screening germplasm and identifying resistant sources. Seventy four diseased root samples were collected from farmer's fields belonging to four major mulberry growing states of South India. Based on morpho-cultural and scanning electron microscopy studies, 57 fungal isolates were characterized and identified as L. theobromae. Phylogenetic analysis of concatenated internal transcribed spacer and β-tubulin sequences revealed variation of the representative 20 isolates of L. theobromae. Following the root dip method of inoculation, pathogenicity studies on susceptible mulberry genotypes (Victory-1 and Thailand male) recognized the virulent isolate MRR-142. Accordingly, MRR-142 isolate was used to evaluate resistance on a set of 45 diverse mulberry accessions. In the repeated experiments, the mulberry accession ME-0168 which is an Indonesian origin belonging to Morus latifolia was found to be highly resistant consistently against BRR. Eight accessions (G2, ME-0006, ME-0011, ME-0093, MI-0006, MI-0291, MI-0489, and MI-0501) were found to be resistant. These promising resistant resources may be exploited in mulberry breeding for developing BRR resistant varieties and to develop mapping populations which successively helps in the identification of molecular markers associated with BRR.

• The Plant Pathology Journal
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• 제31권2호
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• pp.132-139
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• 2015

Bt-cotton germplasm, consisting of 75 genotypes was evaluated against cotton leaf curl disease (CLCuD) under high inoculum pressure in the field and using graft inoculation in glasshouse by visual symptom scoring assessments. None of the tested genotype was found disease free under both evaluation tests. Under field conditions in 2011, 3 genotypes were found resistant, 4 moderately resistant, 3 tolerant, 2 moderately susceptible and one susceptible; in 2012, 3 genotypes were tolerant, 7 moderately susceptible, 5 susceptible and 38 highly susceptible; in 2013, one was moderately susceptible and 51 were highly susceptible with varying degree of percent disease index (PDI) and severity index (SI). However, through graft evaluation in glasshouse, none of the graft inoculated plant was symptomless. All tested genotypes showed disease symptoms with SI values ranging between 5.0 and 6.0, and latent period between 12 and 14 days. Of the 75 genotypes evaluated using graft inoculation, 11 were found susceptible with SI values of 5.0 to 5.4 while remaining 64 were highly susceptible with SI values of 5.5 to 6.0. Inoculated plants of all tested genotypes exhibited severe disease symptoms within 10 days after the appearance of initial symptoms. No reduction in SI value was observed until the end of the experiment i.e., 90 days after grafting. Information generated under the present study clearly demonstrates that no sources of resistance to CLCuD are available among the tested Bt-cotton genotypes. So, a breeding programme is needed to introgress the CLCuD-resistance from other resistant sources to agronomically suitable Bt-cotton genotypes.

• 원예과학기술지
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• 제30권2호
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• pp.185-191
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• 2012

본 시험은 고추의 육종을 위한 병 저항성 고추를 선발하고자 하였다. 국내에서 시판중인 역병 저항성 품종인 PR계통 21품종, 미국에서 도입해온 36품종과 역병감수성 품종인 '슈퍼마니따'를 사용하여 역병, 탄저병, 흰가루병의 병 저항성 검정을 수행하였다. $Phytophthora$ $capsici$에 의해 발병하는 고추역병의 유묘검정은 서로 다른 교배형(A1, A2, Sterile)을 가지는 3 균주를 사용하여 접종하였다. 그 결과 대부분의 PR계통 고추들은 각각의 교배형에 대하여 저항성 또는 중도저항성을 나타내는 것으로 조사되었다. '역강홍장군'은 서로 다른 교배형의 세 가지 균주에 대하여 저항성을 나타냈으며, 'PR-다따'와 'PR-마니따'는 각각의 교배형에 저항성 또는 중도저항성을 보였다. 외래종의 경우, 'NuMex J.E.Parker', 'Omni Color'과 'SCM-334' 품종은 세 가지 균주에 저항성을 나타냈고, 'Sweet Banana'와 'Tabasco'를 포함한 몇몇 품종들은 각각의 균주에 중도저항성을 나타냈다. 흰가루병에 대하여 'Orange Habanero', 'black Cuban'은 저항성을 나타냈으며, '슈퍼마니따'와 'PR 금동'은 중도저항성을 나타냈다. 'Santa Fe Grnade', 'NuMex Pinata' 품종은 흰가루병에 매우 심한 감수성인 것으로 조사되었다. 탄저병의 경우, 'Aji Limon'과 'C. baccatum var. pendelum 3-4' 품종은 저항성인 것으로 조사되었다. 'Pobalno', 'Omni Color', 'Negro', 'Mesilla', 'Mulato', 'Bhut Jolokia', 'Big Dipper', 'Black Cuban', 'NuMex Pinata'와 'NuMex Big Jim'은 중도저항성을 나타내는 것으로 조사되었다. '태산'을 제외한 대부분의 PR계통들은 탄저병에 대하여 감수성 내지 심한 감수성인 것으로 확인되었다. 본 연구에서 확인된 저항성 개체는 이후에 고추 병저항성 육종에 유용한 유전자원으로 이용될 수 있다.

• Journal of Microbiology
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• 제45권5호
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• pp.379-387
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• 2007

A hundred and seventeen antibiotic-resistant Escherichia coli strains were isolated from public tap and spring waters which were polluted by fecal coliforms. There were no significant differences between two water sources as to the coliform pollution level (p> 0.05). All E. coli isolates were detected to be resistant to one or more antibiotics tested. Nearly 42% of the isolates showed multiresistant phenotype. Three (2.5%) of these isolates contained class 1 integron. Sequencing analysis of variable regions of the class 1 integrons showed two gene cassette arrays, dfr1-aadA1 and dhfrA17-aadA5. Resistance to ampicillin, tetracycline or trimethoprim-sulfamethoxazole was transferable according to the results of conjugation experiments. The rate of tetracycline resistance was 15%. tet(A)-mediated tetracycline resistance was widespread among tetracycline-resistant E. coli isolates. Genotyping by BOX-polymerase chain reaction (BOX-PCR) showed that some of the strains were epidemiologically related. This is the first report on the prevalence and characterization of class 1 integron-containing E. coli isolates of environmental origin in Turkey.

• Clinical and Experimental Pediatrics
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• 제52권5호
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• pp.529-537
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• 2009

Drug-resistant tuberculosis in children has important implications for both the patients and tuberculosis control programs. In Korea, among all new patients, the isoniazid resistance rate was 9.9% and multidrug-resistant tuberculosis rate was 2.7% in 2004 (in patients aged 10-19 yr, the multidrug-resistant tuberculosis rate reached 2.1%). Tuberculosis in pediatric patients is difficult to diagnose because many children have nonspecific clinical signs and the detection rates of acid-fast bacilli smears and cultures are low. Therefore, every effort should be made to identify adult sources and obtain information on drug susceptibility because symptomatic adult patients have a higher chance of culture positivity and drug-susceptibility patterns are the same in most adult-child pair patients. Korean children are at significant risk of drug-resistant tuberculosis. As the isoniazid resistance rate is greater than 4% among the new cases in Korea, a four-drug regimen should be considered for initial treatment of children with active tuberculosis, unless drug-susceptibility test results are available. Treatment of drug-resistant tuberculosis in children is challenging and there are only few available data. Tuberculosis control programs should be continuous with specific focus on pediatric populations because they can serve as reservoirs for future active cases. Further studies are needed regarding treatment of drug-resistant tuberculosis in children.

• 문화기술의 융합
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• 제5권1호
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• pp.99-105
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• 2019

본 연구는 성인남성 30명의 심층인터뷰를 통하여 금연공익광고에 대한 호감, 공감, 심리적 저항의 반응을 분석하였다. 연구결과, 금연공익광고에 대하여 비흡연자는 호감 반응을 나타낸 반면 흡연자는 비호감 반응이 많았다. 또한 4 50대 흡연자의 광고 공감도가 2 30대에 비해 높게 나타나 연령에 따른 광고 공감도의 차이를 보였다. 흡연자들은 금연메시지에 대해 다양한 방식의 심리적 저항을 시도하고 있으며 특히 정보원 폄하를 포함한 정보원에 대한 저항 전략을 주로 시도하고 있다. 본 연구결과에 근거하여 금연공익광고의 효과를 제고할 수 있는 방안이 제안되었다.