Comparisons of Pathological Responses in Carrot to Root-knot Nematodes

Seo, Yunhee,Kim, Yong Su,Park, Yong,Kim, Young Ho The Korean Society of Plant Pathology 2015 Plant Pathology Journal Vol.31 No.4

Carrot (Dacus carota var. sativus) is one of the top-ten most economically important vegetable crops produced worldwide, and the root-knot nematodes, Meloidogyne spp., are one of the most important pests in the carrot. In Korea, M. hapla and M. incognita are presumed to be the major root-knot nematodes distributing mostly in open carrot fields and greenhouses, respectively. In our study, currently-developed and commercial carrot cultivars and the parental lines were examined for their pathological responses to M. incognita and M. hapla 7 weeks after inoculation with about 1,000 second-stage juveniles (J2) of the nematodes. All the carrot cultivars and lines showed susceptible responses to both nematodes with the gall index (GI) of 2.4-4.4, which were always higher on the carrot plants infected with M. incognita than M. hapla. Gall sizes were remarkably larger with more serious reduction of the root growths in the plants infected with M. incognita than M. hapla, suggesting the carrot lines examined in our study were more susceptible to the former than the latter. In the infection sites of the root tissues, giant cells were more extensively formed, occupying larger stellar regions with the prominent destruction of adjacent xylem vessels by M. incognita than M. hapla. All of these results suggest M. incognita affect more seriously on the carrot plants that are grown in greenhouses, compared to M. hapla that has a major distribution in open carrot fields, which would be used for determining cropping systems based on target nematode species, their damage and pathological characteristics.

Control of Meloidogyne incognita Using Mixtures of Organic Acids

Seo, Yunhee,Kim, Young Ho The Korean Society of Plant Pathology 2014 Plant Pathology Journal Vol.30 No.4

This study sought to control the root-knot nematode (RKN) Meloidogyne incognita using benign organo-chemicals. Second-stage juveniles (J2) of RKN were exposed to dilutions (1.0%, 0.5%, 0.2%, and 0.1%) of acetic acid (AA), lactic acid (LA), and their mixtures (MX). The nematode bodies were disrupted severely and moderately by vacuolations in 0.5% of MX and single organic acids, respectively, suggesting toxicity of MX may be higher than AA and LA. The mortality of J2 was 100% at all concentrations of AA and MX and only at 1.0% and 0.5% of LA, which lowered slightly at 0.2% and greatly at 0.1% of LA. This suggests the nematicidal activity of MX may be mostly derived from AA together with supplementary LA toxicity. MX was applied to chili pepper plants inoculated with about 1,000 J2, for which root-knot gall formations and plant growths were examined 4 weeks after inoculation. The root gall formation was completely inhibited by 0.5% MX and standard and double concentrations of fosthiazate; and inhibited 92.9% and 57.1% by 0.2% and 0.1% MX, respectively. Shoot height, shoot weight, and root weight were not significantly ($P{\leq}0.05$) different among all treatments and the untreated and non-inoculated controls. All of these results suggest that the mixture of the organic acids may have a potential to be developed as an eco-friendly nematode control agent that needs to be supported by the more nematode control experiments in fields.

Screening and Histopathological Characterization of Korean Carrot Lines for Resistance to the Root-Knot Nematode Meloidogyne incognita

Seo, Yunhee,Park, Jiyeong,Kim, Yong Su,Park, Yong,Kim, Young Ho The Korean Society of Plant Pathology 2014 Plant Pathology Journal Vol.30 No.1

In total, 170 carrot lines developed in Korea were screened for resistance to Meloidogyne incognita race 1 to select parental genetic resources useful for the development of nematode-resistant carrot cultivars. Using the gall index (GI), gall formation was examined on carrot roots inoculated with approximately 1,000 second-stage juveniles of the nematode 7 weeks after inoculation. Sixty-one carrot lines were resistant (GI ${\leq}1.0$), while the other 109 were susceptible (GI > 1.0) with coefficient of variance (CV) of GI for total carrot lines 0.68, indicating low-variation of GI within the lines examined. The histopathological responses of two carrot plants from resistant and susceptible lines were examined after nematode infection. In susceptible carrots, giant cells formed with no discernible necrosis around the infecting nematodes. In the resistant carrot line, however, no giant cells formed, although modified cells were observed with extensive formation of necrotic layers through their middle lamella and around the infecting nematodes. This suggested that these structural modifications were related to hypersensitive responses governed by the expression of true resistance genes. Therefore, the Korean carrot lines resistant to the nematode infection are potential genetic resources for the development of quality carrot cultivars resistant to M. incognita race 1.

First report of Lasiodiplodia theobromae causing dieback of fig in Korea

Yunhee Seo,Mi-Jeong Park,Chang-Gi Back,Jong-Han Park 한국농약과학회 2018 한국농약과학회 학술발표대회 논문집 Vol.2018 No.10

First report of Pseudomonas viridiflava causing leaf spot on cucumber in Korea

Yunhee Seo,Mi-Jeong Park,Chang-Gi Back,Jong-Han Park 한국농약과학회 2018 한국농약과학회 학술발표대회 논문집 Vol.2018 No.10

Pathological Interrelations of Soil-Borne Diseases in Cucurbits Caused by Fusarium Species and Meloidogyne incognita

Seo, Yunhee,Kim, Young Ho The Korean Society of Plant Pathology 2017 Plant Pathology Journal Vol.33 No.4

Pathological interrelations of two soil-borne diseases in cucurbits (watermelon, oriental melon, shintosa and cucumber) caused by Fusarium isolates (FI) and the root-knot nematode (RKN), Meloidogyne incognita were characterized by the fusarium disease severity index (DI), RKN gall index (GI) and eggmass index (EI) in inoculation tests using FI and RKN. Virulence of FI as determined by DI at 4 weeks after inoculation was mostly in the higher order of Fusarium proliferatum F6, F5 and Fusarium oxysporum f. sp. melonis or Fusarium oxysporum f. sp. niveum with no significant differential interactions among the cucurbits and RKN co-infection. Significant increases of DI due to RKN coinfection were noticed in watermelon and oriental melon infected with F. proliferatum isolates, suggesting the DI increase due to RKN coinfection may depend upon the virulence of FI relative to aggressiveness of RKN on the cucurbits. For the coinfection of FI and RKN, GI and EI were mostly reduced logarithmically with the increase of DI, largely more in EI than GI, in all cucurbits except for shintosa. Microscopic examination of the root tissues showed histopathological features characteristic to infection types; formation of fungal hyphae and/or spores and plant defense structures (tyloses and mucilage) in variable degrees and formation of giant cells at variable developmental stages and with variable cytoplasmic depletion or degeneration which were visualized in relations with the values of DI, GI and EI. These findings will be helpful to develop control strategies of the soil-borne disease complex based on their pathological characteristics.

First report of charcoal rot on chili pepper caused by Macrophomina phaseolina in Korea

Yunhee Seo,Mi-Jeong Park,Chang-Gi Back,Jong-Han Park 한국농약과학회 2018 한국농약과학회 학술발표대회 논문집 Vol.2018 No.10

Potential Reasons for Prevalence of Fusarium Wilt in Oriental Melon in Korea

Seo, Yunhee,Kim, Young Ho The Korean Society of Plant Pathology 2017 Plant Pathology Journal Vol.33 No.3

This study aims to examine the potential reasons for the current prevalence of the fusarium wilt in the oriental melon. Twenty-seven Fusarium isolates obtained from oriental melon greenhouses in 2010-2011 were identified morphologically and by analysis of elongation factor-1 alpha gene (EF-$1{\alpha}$) and internal transcribed spacer (ITS) rDNA sequences as 6 Fusarium species (8 isolates of F. oxysporum, 8 F. commune, 5 F. proliferatum, 3 F. equiseti, 2 F. delphinoides, and 1 F. andiyazi), which were classified as same into 6 EF-$1{\alpha}$ sequence-based phylogenetic clades. Pathogenicity of the Fusarium isolates on the oriental melon was highest in F. proliferatum, next in F. oxysporum and F. andiyazi, and lowest in the other Fusarium species tested, suggesting F. proliferatum and F. oxysporum were major pathogens of the oriental melon, inducing stem rots and vascular wilts, respectively. Oriental melon and watermelon were more susceptible to F. oxysporum than shintosa and cucumber; and cucumber was most, oriental melon and watermelon, medially, and shintosa was least susceptible to F. proliferatum, whose virulence varied among and within their phylogenetic subclades. Severe root-knot galls were formed on all the crops infected with Meloidogyne incognita; however, little indication of vascular wilts or stem and/or root rots was shown by the nematode infection. These results suggest the current fungal disease in the oriental melon may be rarely due to virulence changes of the fusarium wilt pathogen and the direct cause of the severe root-knot nematode infection, but may be potentially from other Fusarium pathogen infection that produces seemingly wilting caused by severe stem rotting.

서비스 질이 고객만족과 고객충성에 미치는 영향

서윤희(Seo, Yunhee),김병규(Kim, Byungkyu) 서울행정학회 2015 한국사회와 행정연구 Vol.25 No.4

정책환경 변화와 지역사회복지서비스의 전문화 요청에 따라 노인복지관과 장애인복지관 등 단종복지관이 지속적으로 확대되어 왔다. 본 연구는 이러한 사회복지관의 유형에 따라 어떠한 공통점과 차이점이 있는지를 탐색하기 위한 것이다. 구체적으로 SERVPERF 척도를 이용하여 노인복지관과 장애인복지관의 서비스 질 요인이 고객만족과 충성에 미치는 영향을 비교분석하였다. 분석결과 사회복지관 유형별로 서비스 질이 고객만족과 충성에 미치는 영향에 차이가 있는 것으로 나타났다. 노인복지관의 경우 보증성과 공감성이 고객만족을 통해 고객충성에 영향을 미치는 반면, 장애인 복지관의 경우 신뢰성과 유형성이 고객만족을 통해 고객충성에 간접적 영향을 미치는 동시에 신뢰성이 직접적인 영향을 미치는 것으로 나타났다. 이러한 분석결과는 복지관의 유형에 따라 서비스의 질과 고객에 대한 차별적인 관리전략이 필요하다는 것을 강조하는 것이다. specific welfare center such as rehabilitation center for the disabled and senior welfare center except for existing community welfare center, has increased as environmental change of policy and demand of specialization of regional welfare service. This study explored the similarity and difference due to type of social welfare center. Specifically, the study explored the impact of service quality of rehabilitation center for the disabled and senior welfare center on customer satisfaction and customer loyalty using SERVPERF. In the results, there is difference in the impact of service quality of welfare center on customer satisfaction and customer loyalty between rehabilitation center for the disabled and senior welfare center. Assurance and empathy affect customer loyalty through customer satisfaction indirectly in senior welfare center while reliability and tangibles affect customer loyalty through customer satisfaction indirectly as well as reliability affect customer loyalty directly in rehabilitation center for the disabled. These findings suggest different strategies are required to meet the demand of specific welfare customers.

임진왜란의 기억과 박물관 역사 전시의 구현

서윤희(SEO Yunhee) 한림대학교 태동고전연구소 2019 泰東古典硏究 Vol.43 No.-

본고는 임진왜란의 흔적과 집단기억이 박물관 역사 전시 속에 어떻게 구현되었는가를 검토 하려는 데 목적이 있다. 임진왜란의 현장이었던 진주성 전투와 관련하여 만들어진 역사적 기억으로는 첫째, 진주와 진주성이 갖는 전략적 위치의 중요성, 둘째, 제1차 진주성 전투의 승리가 가능했던 철저한 준비 및 일관된 지휘체계, 의열의 상징이었던 제2차 진주성 전투, 셋째, 새로운 기억이 덧붙여진 의기 논개의 이야기이다. 진주성에 대한 기억은 진주성 안에 사당, 비석 등의 기념물로 시각화되었고 이들은 추모의 성격과 정보를 알리는 데 주목적이 있었다. 진주성 안에 위치하는 국립진주박물관은 임진왜란 전문 박물관으로 임진왜란을 주제로 한 역사 전시를 보여준다. 임진왜란에 대한 단편적인 기억들은 박물관의 실물자료를 통해 재소환되 고, ICT 기술을 바탕으로 한 영상물이나 체험물들은 임진왜란의 역사 기억을 생생히 실감나게 한다. 더욱이 임진왜란에 대한 축적된 연구 성과들은 국난극복의 민족주의적인 시각에서 벗어나 국제적 감각으로 역사 전시를 구현하게 해준다. 정보가 공유되는 사회에서 관람객들은 일방적인 관람을 지양하고 자신이 주도하는 학습을 박물관에서 요구하게 되었다. 또한 임진왜란의 기억들은 역사 전시를 통한 다양한 체험과 함께 새로운 역사 읽기를 시도하게 될 것이다. The purpose of this paper is to examine how traces of the Japanese Invasions of Korea and collective memories of the war have been embodied in the museum s history exhibitions. Historical memories which have made in relation to the Battles of the Jinju Fotress, one of the fiercest battlefield during the Imjin War can be categorized into three. First involves the importance of the strategic location of Jinju and the Jinju Fortress. Second is related to the thorough preparation and consistent command system which led to victory of the First Battle of the Jinju Fortress and the Second Battle of the Fortress, which has become symbolic of patriotic struggle, and third is about the story of Nongae, a righteous courtesan(gisaeng) with new memories added. The memories of the Jinju Fortress have been visualized as monuments such as shrines and tombstones inside the fortress, with focus on providing related information and cherishing the memories. Located inside the Jinju Fortress, the Jinju National Museum, dedicated to the Japanese Invasions of Korea, displays historical exhibitions under the theme of the Imjin War. The fragmentary memories of the Imjin War are recalled through the museum s collection, while video clips and experience-based ICT technologies provide vivid memories of the history of the war. Moreover, the accumulated research achievements allow us to understand the war in an international perspective away from a nationalistic view. As we live in an era where information is shared not possessed, museum visitors want their museum experiences to be more active. The historical exhibitions of the Imjin War will meet their needs by providing various experiences and that will allow them to have a fresh eye on the memories of the Imjin War.