• 한국토양비료학회지
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• 제50권4호
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• pp.215-225
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• 2017

Kiwifruit is prone to damage by frost in the harvest season and the occurrence of postharvest diseases. Accordingly, new cultivars overcoming these disadvantages have been developed. Compared to existing cultivars, studies on diseases in new cultivars are very limited. Thus, goal of this study was investigation of fungal infection occurrences in new cultivars. Kiwifruit was harvested in 2014 and 2015 year, respectively. In both years, cvs. Goldone and Redvita showed more resistance against fungal infection but cv. Gamrok was more sensitive compared with cv. Hayward. Major fungi were identified as Botryosphaeria dothidea, Phomopsis sp., Alternaria alternata and Nigrospora sp. Firmness and soluble solids content were also influenced by the occurrences. This study's findings are important for providing practical information on new cultivars in the kiwifruit industry.

• 한국조경학회지
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• 제22권4호
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• pp.95-117
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• 1995

This study was carried out to investigate Korean native trees in the America landscape through arboretums, the plant inventory of America, computer files for accessions from Korea, source lists of plants and seeds, and seed and plant nursery company. The results were as follows; 1. Korean native trees introduced in America and Canada were 119 species, 116 species were being cultivated in arbrids were being sold in nurseries, new cultivars were selected from 32 species, and hybrids were bred from 5 species. 2. Abies koreana, Malus baccata, and Stewartia koreana were being cultivated in many arboretums and sold in many nurseries. Also there were new hybrids as well as new cultivars. 3. 25 species including Albizzia julibrissin were being cultivated in many arboretums and sold in many nurseries. Also there were new hybrids. 4. Ilex integra and Ilex rotunda were being cultivated in many arboretums and sold in many nurseries. There were no new cultivars, but there were new hybrids. 5. 44 species including Abies holophylla were being cultivated in many arboretums and sold in many nurseries. There were no new cultivars or hybrids. 6. Populus tremula var. davidiana was being cultivated in many arboretums. There were new cultivars of 'Erecta', 'Gigas', 'Pendula', but no new hybrids. They were not sold by any nurseries. 7. 41 species including Abies nephrolepsis were being cultivated in many arboretums. But they were not sold by any nurseries. They didn't have any new cultivars or hybrids. 8. Diospyros kaki 'Kyungsan Bansi', Elaeocarpus sylvestris var. ellipticus, and Pyrus serotina 'Dankae' were not being cultivated in arboretums in America but some nurseries were selling those species as well as new cultivars. 9. Only 3 species (Berchemia berchemiaefolia, Carpinus eximia, and Chionanthus retusus var. coreana which are native Korean plants) were not introduced in America or Canada.

• The Plant Pathology Journal
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• 제40권2호
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• pp.151-159
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• 2024

Bacterial soft rot caused by Pectobacterium carotovorum subsp. carotovorum (Pcc) is one of the most severe diseases in radish cultivation. To control this plant disease, the most effective method has been known to cultivate resistant cultivars. Previously, we developed an efficient bioassay method for investigating resistance levels with 21 resistant and moderately resistant cultivars of radish against a strain Pcc KACC 10421. In this study, our research expanded to investigate the resistance of radish cultivars against six Pcc strains, KACC 10225, KACC 10421, ATCC 12312, ATCC 15713, LY34, and ECC 301365. To this end, the virulence of the six Pcc strains was determined based on the development of bacterial soft rot in seedlings of four susceptible radish cultivars. The results showed that the Pcc strains exhibited different virulence in the susceptible cultivars. To explore the race differentiation of Pcc strains corresponding to the resistance in radish cultivars, we investigated the occurrence of bacterial soft rot caused by the six Pcc strains on the 21 resistant and moderate resistant cultivars. Our results showed that the average values of the area under the disease progress curve were positively correlated with the virulence of the strains and the number of resistant cultivars decreased as the virulence of Pcc strains increased. Taken together, our results suggest that the resistance to Pcc of the radish cultivars commercialized in Korea is more likely affected by the virulence of Pcc strains rather than by race differentiation of Pcc.

• The Plant Pathology Journal
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• 제32권5호
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• pp.423-430
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• 2016

Clubroot disease caused by Plasmodiophora brassicae is one of the most serious diseases in Brassica crops worldwide. In this study, the pathotypes of 12 Korean P. brassicae field isolates were determined using various Chinese cabbage including 22 commercial cultivars from Korea, China, and Japan, and 15 inbred lines. All P. brassicae isolates exhibited the typical clubroot disease on non-clubroot resistant cultivar, indicating that the isolates were highly pathogenic. According to the reactions on the Williams' hosts, the 12 field isolates were initially classified into five races. However, when these isolates were inoculated onto clubroot-resistant (CR) cultivars of Chinese cabbage, several isolates led to different disease responses even though the isolates have been assigned to the same race by the Williams' host responses. Based on the pathogenicity results, the 12 field isolates were reclassified into four different groups: pathotype 1 (GN1, GN2, GS, JS, and HS), 2 (DJ and KS), 3 (HN1, PC, and YC), and 4 (HN2 and SS). In addition, the CR cultivars from Korea, China, and Japan exhibited distinguishable disease responses to the P. brassicae isolates, suggesting that the 22 cultivars used in this study, including the non-CR cultivars, are classified into four different host groups based on their disease resistance. Combining these findings, the four differential hosts of Chinese cabbage and four pathotype groups of P. brassicae might provide an efficient screening system for resistant cultivars and a new foundation of breeding strategies for CR Chinese cabbage.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.27-27
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• 2017

The rapid growth of world population, reduction of cultivated areas for crop production, and detrimental effects of pests, diseases, and climate changes have required to breed new rice cultivars with high yield, accepted quality, but strong resistance to abiotic and biotic stresses. However, traditional breeding needs much time to breed a new cultivar, whereas the successful use of molecular breeding is still questionable. We have developed a novel mutation which allow to cross many rice cultivars together with low segregation, that allow to breed a new cultivar in only several cropping. The mechanism has been unknown, but we suggest that gene linkage may play a crucial role, of which the semi dwarf gene might be the center gene for gene linkage occurrence. The phenomenon of this possible gene linkage is contrary to Mendel rules, but it is promising to breed new rice cultivars, of which, the most elite genes in rice might be able to gather in a targeted rice variety.

• The Plant Pathology Journal
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• 제35권6호
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• pp.698-704
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• 2019

Phytophthora root and stem rot (PRSR) caused by Phytophthora sojae is one of the most destructive diseases of soybean. PRSR recently became an issue as soybean cultivation in paddy fields increased in South Korea. The management of PRSR mainly involves R-gene-mediated resistance, however, little is known about the resistance in Korean cultivars. Major Korean soybean cultivars were investigated for the presence or absence of R-gene-mediated resistance to four P. sojae isolates, two of which were new isolates. Isolate-specific reactions were observed following P. sojae inoculation. Of 21 cultivars, 15-20 cultivars (71.4-95.2%) showed susceptible reaction for each isolate. Ten cultivars were susceptible to all the isolates, and six cultivars were identified to have R-gene-mediated resistance to one or two isolates. The results of this study would provide a framework for the discovery of resistant cultivars, development of new cultivars resistant to P. sojae, and investigation of pathogenic diversity of P. sojae population in South Korea.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 2005년도 창립30주년기념 추계 학술대회 및 정기총회
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• pp.3-18
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• 2005

고려인삼 8개 신품종의 특성을 요약하면 아래와 같다. 1) 다경발생율이 연풍은 45%로 가장 높았고, 금품은 7%로 가장 낮았으나, 지상부생육은 금품이 가장 양호 하였고, 연풍이 가장 낮았다. 2) 종자결실율은 금품이 85.4%로 가장 높았으며, 천풍이 69.1%로 가장낮았다. 종자수확량은 연풍이 108.3개로 가장많았고, 천풍이 77.5개로 가장 적었다. 3) 엽소발생율은 천풍이 타품종보다 각년생에서 높았으나 연풍은 다소 낮았다. 4) 뿌리 부위별 무게분포비율에서 동체의 비율이 천풍 등 5품종은 49%-55.9%로 자경재래종 63,1%보다 낮았으나, 지근의 비율은 5개 신품종이 19,3%-23.3%로 자경재래종 13.2% 보다 높았고, 세근은 차이가 없었다. 5) 수량은 연풍>금풍>고풍>천풍=선풍>자경재래증 순으로 연풍이 가장 높았고,동장은 천풍이 8.0cm로 가장 길었으나 연풍이 6.4cm로 가장 짧았다. 적변삼 발생율은 신품종이 0.2-9,5%로 자경재래종 16.3%보다 현저히 낮았다. 6) 천삼의 생출율은 천풍>금풍>고풍>선풍>연풍>청선>자경재래종의 순서로 천풍이 높았으며, 천지삼의 생출율도 같은 경향이었다. 7) 품종별 동체의 단위무게 당 total ginsenosides 함량은 금풍 8.53mg, 연풍8.13mg, 고풍7.47mg로 높았으나, 천풍과 선풍은 각각 5.73mg과 4.87mg로 다소낮았다.

• Journal of Ginseng Research
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• 제26권2호
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• pp.85-88
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• 2002

고려인삼을 순계분리 육성하여 품종 등록한 인삼 신품종의 광도, 온도별 광합성 능력과 광합성 관련 형질인 기공, 엽록소, 비엽중 및 지상하부 형질들을 조사한 결과를 요약하면 다음과 같다. 신품종 및 자경종의 광포화점은 15,000 lux내외였고, 광합성 최적온도는 2$0^{\circ}C$였다. 광합성 능은 연풍>천풍>고풍>자경종 순으로 연풍이 가장 높았다. 호흡속도는 모든 품종이 온도가 높아짐에 따라 빨라지는 경향이었으며, 타품종에 비해 호흡량이 높았다. 비엽중은 천풍>고풍>연풍>자경종 순서로 높았고, 엽록소 함량은 품종간 차이가 근소하였다. 단위면적당 기공수는 연풍이 69.2개로 타계통의 40~47개보다 많았고, 기공의 크기는 연풍이 26.5 $\mu\textrm{m}$ 타품종 37.5~38.8 $\mu\textrm{m}$보다 적었다. 연풍은 경수가 1.8개, 장염수가 7.7개, 소염수가 41.0개, 엽면적이 12.3 dm$_2$로 타 품종보다 지상부의 생육이 양호하였다. 근중은 연풍>천풍>고풍>자경종 순으로 무거웠고, 동장은 천풍과 고풍이 각각 6.5, 6.8 cm로 자경종 5.6 cm보다 길어서 체형이 양호하였으나 연풍은 동장이 4.4 cm로 짧았다.

• 한국식물병리학회지
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• 제14권5호
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• pp.496-501
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• 1998

Incidence of rice blast on new rice cultivars and elite lines was observed from 1995 to 1997 in Icheon, Chuncheon, Jecheon and Naju areas. The observation was made in the nurseries and fields. In the nurseries, three cultivars Grubyeo, Sangjuchalbyeo and Suwon 414 showed moderate levels of resistance to leaf blast, with the disease index 0 to 5. From the field observation, it was found that cultivars Heugjinjubyeo and Unbong 18 were highly resistant to leaf blast, but susceptible to neck blast. In general, there was a great variation yearly and regionally in the incidence of neck blast within the same cultivar, ranging from 0 to 100%. However, the range of neck blast infection was relatively narrower in the cultivars Yunghaebyeo (0∼2.4%) and Suwon 414 (0∼2.2%) during observation period. Races of rice blast fungus were variable at different areas. Among them dominant races were KI-409, KJ-201 and KJ-301.

• 한국식물병리학회지
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• 제13권2호
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• pp.79-84
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• 1997

Incidence of rice blast on new rice cultivars and elite lines was observed from 194 to 1996 in Icheon, Chuncheon, Jecheon and Naju areas. The observations were made in the nuseries and in the fields. In the nurseries, only cultivars Daesanbyeo and Hyangmibyeo 2 showed moderate levels of resistance to leaf blast, with the disease index 0 to 6. From the field observations, it was found that cultivars Hyangmibyeo 2 and Suwon 414 were highly resistant to leaf blast, but susceptible to neck blast. the fields, leaf blast was not observed. In general, there was great yearly and regional variation in the incidence of neck blast within the same cultivars, some times ranging from 0 to 100% of incidence. However, the range of fluctuation in the disease incidence were relatively small in the cultivars Daejinbyeo (0∼17.5%), Daesanbyeo (0∼4.0%), Donganbyeo (0∼21.4%) and Hwasambyeo (0∼13.9%). Hyangmibyeo 2 and Seojinbyeo were rarely infected with neck blast in Chuncheon and Naju all of the years, the same cultivars were severely infested with neck blast; 45.1 and 45.5%, respectively, in Jecheon in 1995. The occurrence of different races of rice blast fungus were different at different areas. However, it was found that in Icheon, Chuncheon, Jecheon and Naju areas, the dominant races were KI-409, KJ-201 and KJ-301.