• 생명과학회지
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• 제7권4호
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• pp.347-354
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• 1997

Some attempts were made to investigate the gentic characteristics of the brown planthopper(BPH), Nilaparvata lugens Sta${\aa}$l, biotypes. In terms of egg and nymphal periods, egg hatcgability, emergence ratio, and population change of BPH and plant damage of rice cultivars by the infestation of BPH biotypes and their hybrid progenies in field conditions. The egg and nymphal periods of the three of BPH biotypes and their hybrid progenies on Dongjinbyeo with no resistance gene were shorter than on rice cultivars with resistance gene. But the periods of biotype-2(♀) X 2(♂) (E) on Samgangbyeo with Bph-1 gene and biotype-3(♀) X 3(♂)(I) on Mirying 63 with bph-2 gene were as short as on Dongjinbyeo. The egg hatchability and emergence ratio of the three Bph biotypes and their hybrid progenies on Dongjinbyeo were higher than on the other rice cultivars, and those of E on Samgangbyeo and I on Miryang 63 were as high as on Dongjinbyeo. In rice paddy field, biotype-1(♀) X 1(♂)(A)$\sim$I infested on Dongjinbyeo, E onSamgangbyeo, and I on Miryang 63 were increased their population densities remarkably in next generation. Dongjinbyeo infested by A$\sim$I, and Myryang 63 infested by I were hopperburned at 60 days after infestation and had a damage rating of 0.9. But Samgangbyeo infested by E was no hopperburn(damage rating: 7.3) though it showed high BPH population at 60 days after infestation.

• 한국응용곤충학회지
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• 제22권2호
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• pp.52-66
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• 1983

The brown planthopper, N. lugens (Stal), has become a serious pest of rice in tropical Asia during the last decade. At high pest density, its feeding damage causes 'hopperburn' or complete wilting and drying of the rice plant. It also transmits grassy and ragged stunt virus diseases. The estimated losses caused by the pest in tropical Asia exceed $US\$300$ millions. While cultivation of resistant rice varieties has proved to be highly effective against the pest, their long-term stability is threatened because of the evolution of prolific biotypes which can destroy these varieties. At present, identification of biotypes is based principally on the differential reactions of host rice varieties to the pest and on host-mediated behavioral and physiological responses of the pest. Recent findings of morphological differences in adult rostrum, legs, and antennae, body parts that possess receptors for host plant location and discrimination, and cytological differences in N. lugens populations maintained as stock cultures strongly complement other biotype studies. So far, three N. lugens biotypes have been identified in the Philippines. Biotype I can survive on and damage varieties that do not carry and genes for resistance, while Biotype 2 survives on resistant varieties carrying Bph 1 gene and Biotype 3 on varieties carrying gene bph 2. However, none of these biotypes can survive on varieties with genes Bph 3 or bph 4. Several varieties which are resistant in the Philippines are susceptible in India and Sri Lanka as the South Asian biotypes of N. lugens are more virulent than Southeast Asian biotypes. To monitor the pest biotypes in different geographical regions and to identify new sources of resistance, an International Brown Planthopper Nursery has been established in many cooperating countries. The evolution of biotypes is an exceedingly complex process which is governed by the interactions of genetic and biological factors of the pest populations and the genetic makeup of the cultivated varieties. While the strategy for sequential release of varieties with major resistance genes has been fairly successful so far, the monegenic resistance of these varieties makes them vulnerable to the development of the pest biotypes. Therefore, present breeding endeavors envisage utilizing both major and minor resistance genes for effective control of the pest.

• Weed & Turfgrass Science
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• 제6권4호
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• pp.350-354
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• 2017

Conyza canadensis is the weed species which most frequently develops resistance to glyphosate in many agricultural crop fields. The continuous use of glyphosate has resulted in the spontaneous occurrences of resistant biotypes. This research was conducted to investigate the response of suspected C. canadensis biotypes to glyphosate. Seeds of C. canadensis were collected from 18 sites in tangerine orchards in Jeju province of Korea. In the preliminary screening, 6 resistant and 12 susceptible biotypes were found at the recommended glyphosate rate ($3.28kga.i.ha^{-1}$). The susceptible biotypes were completely killed at the field application rate whereas the resistant biotypes were initially injured but recovered 14 days after glyphosate application. This is the first case of glyphosate resistance found in Korea despite the national ban on genetically modified glyphosate tolerant crops cultivation. Extended monitoring should be conducted to understand how widely spread the glyphosate resistant C. canadensis is and to estimate the severity of this weed problem in the tangerine orchards of Korea.

• The Korean Journal of Ecology
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• 제26권2호
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• pp.82-86
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• 2003

We investigated the variation in adaptation to growth for four ecotypically-differentiated population of Taraxacum officinale found naturally in temporal environmental heterogeneity. Seeds collected from the four seasons were germinated in incubators and were grown for four months in greenhouse to test genetic variation among biotypes. Biotypes, segregated by seeds collected seasonally, were the part of natural population in Mokpo, South Korea. Each biotype was different in total dry weight of seeds, biomass, and leaf area, confirming previous finding. Differences between biotypes grown under a common environment indicated a genetic basis to their distinct demographic rates. Therefore, biotypes with similar annual rates of growth and contrasting seasonal rates should persist in the population. This differential response suggests that temporal variation in environment may be responsible, in part, for the maintenance of genetic variation within populations.

• 한국응용곤충학회지
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• 제26권2호
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• pp.63-69
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• 1987

유묘(幼苗)의 저항성반응(抵抗性反應)은 추청(秋晴)벼가 생태형교잡종(生態型交雜種) 모두에 감수성(感受性)이었고, 청청(靑靑)벼는 생산형(生産型) $2(female){\times}2(male)$, 밀양63호(密陽63號)는 생태형(生態型)$3(female){\times}3(male)$에 감수성(感受性)이었다. 청청(靑靑)벼와 밀양63호(密陽63號)는 생태형(生態型)$2(female){\times}3(male)$과 $3(female){\times}2(male)$우에 중간성(中間性)이었다. 식이(食餌) 및 산란선호성(産卵選好性)은 추청(秋晴)벼에서 생태형(生態型) 교잡종(交雜種) 모두 높은 선호율(選好率)을 보였고, 청청(靑靑)벼에는 생태형(生態型) $2(female){\times}2(male),\;2(female){\times}3(male)\;3(female){\times}2(male)$, 밀양63호(密陽63號)에는 생태형(生態型) $3(female){\times}3(male),\;2(female){\times}3(male),\;3(female){\times}2(male)$이 높은 선호율(選好率)을 나타냈다. 모든 생태형(生態型) 교잡종(交雜種)의 섭식량(攝食量)은 추청(秋晴)벼에서 많았으며, 청청(靑靑)벼에는 생태형(生態型) $2(female){\times}2(female),\;3(female){\times}2(male)$, 밀양63호(密陽63號)에는 생태형(生態型) $3(female){\times}3(male),\;3(female)x2(male)$의 섭식량(攝食量)이 많았다.

• 한국응용곤충학회지
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• 제32권1호
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• pp.68-75
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• 1993

우리나라에 발생하고 있는 벼멸구 생태형의 형태적 차이를 구명하고자 생태형 1, 2, 3의 단시형 암컷과 숫컷의 다리부분의 형태를 관찰하였다. 앞다리, 가운데 다리 그리고 뒷다리의 제3부절의 형태를 51개 부위에서 조사한 다음 통계학적 분석을 위하여 정준 판별 분석법을 도입하였다. 각 생태형간의 Mahalanobis distance는 숫컷의 경우 생태형 2와 3 사이에서 가장 짧았고, 암컷은 생태형 1과 2 사이에서 가장 길었다. Scatter plot diagram상에서 각 생태 형간 분리현상이 뚜렷하여 중심점이 각각 다르게 나타났고 각 생태형에 속하는 개체는 중심점 부근에 고르게 분포하였다. 각 생태형간의 Group membership 조사에서 암수 모두 각 생태형은 각각 동일한 생텨형을 분류되었다.

• 한국응용곤충학회지
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• 제53권4호
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• pp.465-472
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• 2014

담배가루이(Bemisia tabaci)는 바이러스 매개 역할과 함께 참외에 심각한 경제적 피해를 주고 있다. 담배가루이는 기주 작물과 농약 감수성 정도에 따라 다양한 생태형으로 분류되고 있다. 본 연구는 안동시 풍천면에 소재한 참외밭에서 성충을 채집하여 PCR 분자진단기법으로 동정하였다. 전체 11 곳의 채집 장소에서 Q 생태형 담배가루이를 진단하였고, 이 가운데 4 곳의 채집 장소에서 B 생태형도 검출되었다. 이러한 결과는 경북지역 참외 재배지에서 담배가루이가 발생한다는 최초의 보고이며, 특히 두 생태형이 동일한 재배지에 혼재한다는 것을 나타낸다.

• 대한수의학회지
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• 제30권2호
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• pp.193-201
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• 1990

An attempt was made to isolate Salmonella(S) organisms from a total of 4,587 fecal samples of birds during the period from May 1987 to March 1988, and serotype and biotypes of the isolates were also investigated. One hundred and sixty-six Salmonella strains were isolated from 151(3.3%) of 4,587 fecal samples of birds, and their serotype was all identified as S typhimurium var copenhagen. The positive samples of S typhimurium var copenhagen were 149 samples(5.1%) in pigeons and 2 samples (0.8%) in aquatic birds. No Salmonella was obtained from ducks, pheasant, and other birds. The isolation frequencies of S typhimurium var copenhagen from pigeons varied from 1.1 to 12.8% at 5 parks, it was higher in September and November. Biotypes of 166 S typhimurium var copenhagen strains isolated from pigeons and aquatic birds were all biotype 10 according to Brandis' method, and were biotype 25hi (78.3%), 27 hi (14.5%), 25 fhi (3.6%), 25 bhi (1.8%), 27 bhi (0.6%), 27 hiz (0.6%), and 9 hi (0.6%) according to Duguid's scheme. Appearance of different biotypes indicated the occurrence of exotic infection sources on the parks.

• 한국응용곤충학회지
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• 제31권4호
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• pp.366-370
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• 1992

벼멸구 수컷 정소에서 염색체의 변이정도를 생태형 별로 관찰하였다. 세포 분열 지수는 생태형 3에서 가장 높았고 그 다음으로 생태형 1, 생태형 2이었다. Agmatoploidy, aneuploidy, 성염색체의 loose pairings과 같은 염색체의 구조적 변화는 생태형 1, 생태형 2, 생태형 3순으로 높았다. 감수분열 제1분열기 중기는 성염색체가 상염색체로부터 현격하게 분리되어 있는 세포의 수는 생태형 2에서 가장 높았다.

• 한국응용곤충학회지
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• 제32권3호
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• pp.317-322
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• 1993

벼멸구 생태형 1, 2, 3의 형태의 차이를 구별하고자 장시형과 단시형 암수를 대상으로 형태적 변화를 관찰하였다. 암컷은 생식 부위인 Abdominal lateral lobes의 좌우 부위를 비교 조사하였다. 수컷은 앞다리, 가운데 다리, 뒷다리 부절의 Unguitractor plate를 조사하였다. 생태형 2의 단시형 암컷은 Abdominal lateral lobes의 기부가 잘라진 것으로 생태형 1과 3보다 많았다. Unguitractor plate의 경우 생태형 2는 장단시형 암 수 모두 부절 안쪽으로 함입되어 있었다.