• Korean journal of applied entomology
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• v.13 no.4 s.21
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• pp.227-231
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• 1974

During the period from 1971 to 73 physiologic races of potato late blight pathogen, Phytophthora infestans, causing severe losses of seed potato production at Alpine area, Korea, were investigated. In 1971, 68 isolates of the pathogen from various potato varieties were identified by the use of differential host Plants, and found that there were 10 races; 0, 1, 2, 3, 1.3, 1.4, 3.4, 1.3.4, 2.3.4. The most Predominant races for the year were 0 and 3. In 1972, the same procedure was repeated with 62 isolates of the pathogen, and found 5 different races; 0, 1, 4, 1.3 and 1.3.4. The most predominant race for the year was race 0. In 1973, six races; 0, 3, 4, 1.3, 3.4 and 1.3.4 were found from 76 isolates of the year, and the race 0 and 4 apperared as the most Predominant races for the year. Total of 11 races; 0, 1, 3, 4, 1.3, 1.4, 3.4, 1.3.4, 2.3.4 and 1.2.3.4, were found during the period from 1971 to 73 at Alpine area, among which the most predominant races were race 0, 3, and 4. The investigation indicated that the anual incidence of these races largely depended on the climatic conditions of the year.

• Korean Journal Plant Pathology
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• v.3 no.4
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• pp.245-251
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• 1987

Soybean cultivars were inoculated with mixtures of races 3 and 4 of the soybean cyst nematode(SCN), Heterodera glycines Ichinohe. On a susceptible soybean cultivar Lee, the relative female maturation of the race mixture was not significantly different when compared with the maturation potentials for each of the two races alone. However, female maturation was significantly lower for the mixture than' for race 4 alone on the soybean cultivas Pickett and Mack which are susceptible to only race 4. Selection of SCN populations consisting of race 3 and race 4 resulted in a decrease in race 4 on soybean cultivars Lee and Bragg which are susceptible to all SCN races and an increase in race 4 on soybean cultivars Pickett and Peking which are susceptible to only race 4. A significant reduction of race 4 was also observed on Lee with most mixtures of race' 3 and race' 4 combined in several ratios, suggesting that race 3 was more competitive than race 4 on the susceptible soybean.

• Korean Journal Plant Pathology
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• v.11 no.2
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• pp.139-145
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• 1995

경남지방에서 벼도열병균 race의 분포상황을 알기 위하여 1990∼1994년 5개년간 경남지역의 재배품종 잎동열병 병반에서단포자 분리하여 얻은 균주 509 균주를 사용하여 연도별 race 분포상황을 조사한 결과는 다음과 같다. 도내에 분포한 race의 종류는 총 33종류였다. 이 중 KI 100군 race가 16종류로 연차간 분포변동이 심하였고, KI 400군 race가 6종류, KJ 100군 race가 4종류, KI 300군 race가 3종류, KJ 200군 race 2종류, race KJ-301 및 race KJ-401이 각각 1종류씩이었다. KI 및 KJ race의 분포 비율은 각각 11.5∼29.9%와 70.1∼88.5%로 KJ race의 분포밀도가 높았고 분포밀도가 높은 race는 KJ-401 및 KJ-301로 전 race의 26.7∼57.3%를 차지하였다. 지대별 race 구성 특징은 산간 지대에서는 KI race의 분포밀도가 27.3%로 해안지대 6.8%에 비해 훨씬 높았고 KJ 100군 race도 27.7%로 해안지대 11.7%보다 분포비율이 높았다. 반대로 KJ 200군 race는 해안지대가 22.0%로 산간지대 9.7%보다 아주 높았다. 조사기간중 재배된 벼품종과 race의 분포변동을 미루어 보아 race의 분포는 재배된 벼의 도열병균 race에 대한 반응형과 관련이 있을 것으로 사료된다.

• Korean journal of applied entomology
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• v.26 no.4 s.73
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• pp.203-207
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• 1987

Studies were conducted to investigate the race distribution of soybean cyst nematode (Heterodera glycines Ichinohe) in Korea. The results are abstracted as follows. The soybean cyst nematode populations collected from Kangwon Province were identified as races 1 and 3; the nematode populations collected from Kyunggi Province were identified as race 3, 5 and c and those collected from Chungnam Province were identified as races 1 and 5. From the total 21 populations 11 populations or 52.4% of the total were race 1; 6 populations or 28.6% of the total were race 5; 3 populations or 14.3% of the total were race 3 and one population or 4.8% of the total were race c. Soybean cyst nematode populations from the same district, at least from the same 'myeon' district were identified as same race. Of these 4, race 3 has not been recorded in Korea yet.

• Korean journal of applied entomology
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• v.22 no.3 s.56
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• pp.208-212
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• 1983

Sixteen recommended soybean cultivars in Korea were tested for resistance to Heterodera glycines. The nubmer of females which developed on roots of cultivars were fewer on 'Hwanggeum kong' and greater on 'Geumgangdaelib'. But there was no resistant cultivar to Heterodera glycines. Four field populations of Heterodera glycines tested for ability to reproduce on five host differentials. Geographical differentiations of H. glycines were newly founded in Korea. These were identlified to race 1 at Hwasun, race 5 at Yangsan and Suweon and Unknown race(or race C) at Seonsan.

• Korean journal of applied entomology
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• v.38 no.3
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• pp.249-253
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• 1999

To study races of Heterodera glycines in Korea, 21 soil samples were collected from eight provinces in 1995. Four races were found; race 3(48%) was a dominant race flowed by race 5(24%), race 1(19%), and race 6(9%). About 30~40% of H. glycines populations reproduced on Pickett and PI88788, while non reproduced on Peking or PI90763. Development of resistant soybean cultivar targeting to race 5 and 6 of H. glycines using PI90763 and PI88788 as a parent is recommended.

• Korean Journal of Childcare and Education
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• v.18 no.2
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• pp.85-103
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• 2022

Objective: This study examined five- to six-year-old children's categorization of mixed-race faces and how it was affected by perceptual individuation training (PIT) for other-races. Methods: Sixty-five children attending classes for 5-year-olds in childcare centers were shown happy and angry faces of Korean and African American mixed-race people, along with neutral faces of Korean and African American monoracial people. They were asked to categorize the faces into same-race or other-race. After the pretest, participants received a PIT for either African American (other-race) or monkeys. Then the racial categorization task was administered again as a posttest. Results: Children showed no general tendency to categorize mixed-race faces as out-group in the pretest. Yet, the PITs further reduced children's categorization of mixed-race faces as out-group. In particular, the effect was clearly evident in children who received the PIT for other-race. Conclusion/Implications: The results suggest that the tendency to categorize mixed-race faces as an out-group may not be evident in early childhood and that experiences of perceptually identifying other-race individuals may help children view mixed-race individuals as being in the ingroup, at least perceptually.

• Journal of Plant Biotechnology
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• v.43 no.1
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• pp.58-65
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• 2016

Powdery mildew is an important disease of the melon (Cucumis melo L.). Seven isolates of powdery mildew fungi were collected from five locations in Korea; Anseong (DH487), Icheon (BN103, BN625, BN968), Yeongam (YA141), Changnyeong (CN582), and Suncheon (SN102). All 7 fungi had a similar trend of conidial chain and conidiophore development as Podosphaera xanthii with fibrosin bodies in mature conidia. Among them, 2 isolates of powdery mildew fungi; CN582 and SN102 showed similar responses to resistance against powdery mildew as the previously reported race 1 and race N2. The isolates YA141 and BN103 showed similar responses as like as race A. However, three isolates of powdery mildew fungi (BN625, BN968, and DH487) showed different responses compared to the previously reported races (1, N1, N2, A, S, and 5). Therefore, these three isolates could be designated as new races in melon. Nine out of 15 commercial melon cultivars in Korea showed resistance to race 1 (CN582). However, the new race BN968 invaded all 15 cultivars. Results of the two molecular markers were consistent in response to disease development by race 1 of Podosphaera xanthii in case of the above mentioned cultivars. This study confirmed the presence of new melon powdery mildew fungi in Korea which are similarly notorious as like as the previously reported race 1. Therefore, breeders can use these two molecular markers for breeding melon in Korea that is resistant to race 1 and as well as to some other races.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.705-709
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• 1998

Temporal and spatial distribution of Korean rice blast fungus (Pyricularia grisea) race KI-409 that has been rapidely increased since 1993 and became predominant in 1995 in Korea were investigated. Varietal resistance of current commercial cultivars of rice to the race was also tested in this study. The race KI-409 was first isolated from rice cv. Namyangbyeo in 1985. Since 1985 the race had been isolated mainly from the rice cultivars having BL1 BL7 pedigree as a resistance source. Distribution ratio of the race in 1995 was 23.7% in average and became a predominant in the P. grisea population in Korea. The race distributed widely and found in all the eight provinces in Korea. Many commercial cultivars such as Chucheongbyeo as well as those with BL1 or BL7 as a genetic background were found to be susceptible to the race KI-409.

• Research in Plant Disease
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• v.26 no.3
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• pp.183-189
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• 2020

Powdery mildew is a common and serious disease of the Cucurbitaceae including cucumber (Cucumis sativus) in most areas of the world. To identify causal agents of the powdery mildew and their physiological race(s), we collected cucumber leaves displaying typical symptoms of powdery mildew from different locations in Korea. Based on morphological and molecular characteristics, all powdery mildew isolates were identified as an obligate biotrophic fungal pathogen, Podosphaera xanthii. After inoculation at melon (Cucumis melo) differentials to identify the fungal race(s), P. xanthii isolate MI180427 and IC190611 were identified as race 1 which has been repeatedly reported as dominant race in Korea. However, another isolate SE180328 produced different disease response in the tested differentials, being identified as race 2 which has not been reported in Korea. To confirm the race of SE180328, we inoculated additional melon differentials and determined the isolate as race 2F that is the prevalent race of powdery mildew in Beijing, China. Report of this new race 2F in Korea will be helpful for future breeding programs to develop resistant varieties to this race.