Identification of a gene contributing to the pod dehiscence using candidate gene approach in soybean [Glycine max (L.) Merr.]

Green Jhang,Myoung Hai Kwak,Moon Young Kim,Sung Taeg Kang,Suk Ha Lee 한국육종학회 2009 한국육종학회 학술발표회 발표요지 Vol.41 No.1

Distribution Characteristics, Population Structure and Dynamics of the Endangered Plant, Viola websteri Hemsl.

Hyun-Hee Chae,Young-Chul Kim,Myoung-Hai Kwak,Gi-Heum Nam 한국환경생태학회 2021 한국환경생태학회지 Vol.35 No.1

식물 종은 주어진 환경조건과의 상호작용의 결과로 현재와 같은 특성을 나타낸다. 제비꽃속의 식물은 적응전략으로 개방화와 더불어 왕성한 영양번식체계를 선택하였거나 또는 폐쇄화를 발달시키는 전략을 선택하였다. 왕제비꽃은 제비꽃 속의 식물로 세계적으로 한반도와 중국 지린(길림)성의 동부에만 분포한다. 분포의 중심과 가장자리는 서로 다른 개체군 동태를 나타낼 것으로 예상된다. 왕제비꽃이 복합적인종자생산전략(Mixed-mating strategy)을 소유함에도 현재와 같은 제한적인 분포를 나타내는 원인을 알아볼 필요가 있다. 먼저 우리는 분포지의 식생환경을 조사하여 그 특성을 평가하였다. 식물계절학을 통해 생장특성을 알아보았다. 또한 개체군의 구조, 개방화의 결실특성, 폐쇄화의 생산성을 평가하였다. 그리고 2014년과 2018년 사이의 개체군크기 변화를 비교하였다. 분포지의 대부분은 계곡에 인접한 낙엽활엽수혼효림의 식생하부에 위치하였다. 4∼5월에 자가불화합성의 개방화를 생산하였고 6∼9월까지 폐쇄화를 생산하였다. 폐쇄화의 생산은 불확실한 환경변화에서 종자의 생산을 보증하기 위한 전략으로 평가되며 개방화에 비해 약 2배의 생산량을 나타내었다. 개체군의 구조는 안정적인 지역과 매우 불안정한 지역이 구분되었다. 2014년에 비해 2018년의 조사에서 개체군의 급격한 감소를 경험한 지역이 존재하였다. 이러한 큰 폭의 감소는 가장자리 개체군에서 크게 나타나는 것으로 평가되었다. 왕제비꽃 분포지는 가뭄이라는 자연적인 교란 요인과 분포지를 구성하는 기질에 따른 다양한 미소입지의 존재로 다양한 식물을 부양하였다. 이러한 불확실한 조건에서 폐쇄화를 통해 종자의 생산을 보증하고 그에 따라 자연적인 교란요인이 제거되었을 때 빠르게 유묘의 재정착과 개체군의 보충이 가능한 것으로 판단되었다. 그리고 환경요인은 모든 개체군 및 개체군 내의 모든 개체에 동일하게 작용하지 않는 것으로 추정되었다. 따라서 지역적으로 급격한 개체수의 감소에도 불구하고 완전한 소멸에 이르지 않을 것이고 환경의 변화에 따라 국지적인 소멸과 재정착이 반복될 것으로 예상되었다. 우리는 본 연구를 통해 수집된 종의 특성에 대한 정보를 바탕으로 추가적인 분포지의 조사가 필요함을 제안하였다. 또한 효과적인 보전 전략의 수립과 시행을 위해서는 보다 장기적인 개체군 동태와 개방화와 폐쇄화의 유전적 특성을 평가하는 것이 필요함을 제안하였다. Plant species exhibit current characteristics as a result of interactions with environmental conditions. The plants of Viola sp. have selected chasmogamous flowers with vigorous vegetative propagation or development of cleistogamous flowers as an adaptation strategy. Viola websteri is distributed on the Korean peninsula and the eastern part of Jilin Province, China. The center and edge of the distribution are expected to exhibit different population-dynamics. It is necessary to investigate the cause of its current limited distribution even though V. websteri has a mixed-mating strategy. Firstly, We examined the vegetation environment of habitats and evaluated its characteristics. Growth characteristics were examined through plant phenology. We then evaluated the population structure, characteristics of chasmogamous flowers, and productivity of cleistogamous flowers. Moreover, we compared population sizes between 2014 and 2018. Most habitats were located in deciduous broadleaf mixed forests adjacent to valleys. V. websteri produced chasmogamous flowers with self-incompatibility in April-May and cleistogamous flowers in June-September. The cleistogamous flower production is a strategy ensuring seed production under uncertain environmental fluctuations; these were approximately twice as numerous as chasmogamous flowers. The population structure was distinguished into stable and very unstable regions. There were sites where the population experienced a sharp decline in the 2018 compared to that of 2014. This large decline was found in the edge populations. The habitats had different microsites depending on the natural disturbances of drought and the matrix constituting the habitat, thus supporting various plants. Ensuring the production of seeds through cleistogamous flowers, it was determined that rapid seedling re-establishment and population replenishment were possible when the natural disturbance factor was removed. Environmental factors did not equally affect all populations or individuals. Therefore, it was expected that it would be able to persisted in a long time, despite the rapid decrease in the number of individuals in the population regionally. Local extinction and re-establishment are likely to repeat according to environmental change. We propose the additional population investigation based on this works are required. We also suggest a need to assess the long-term population dynamics and the genetic characteristics of chasmogamous flowers and cleistogamous flowers to establish and implement effective conservation strategies.

MIMO-OFDM 시스템에서 Constant Modulus 신호의 SVR-MMSE 검출 성능 분석

신철민(Chul Min Shin),서명석(Myoung Seok Seo),양청해(Qing Hai Yang),곽경섭(Kyung Sup Kwak) 한국통신학회 2006 韓國通信學會論文誌 Vol.31 No.12A

MIMO-OFDM 시스템에서 constant modulus 신호의 SVR-MMSE 검출 성능 분석

신철민(Shin Chul Min),서명석(Seo Myoung Seok),양청해(Yang Qing hai),곽경섭(Kwak Kyung Sup) 대한전자공학회 2006 대한전자공학회 학술대회 Vol.2006 No.11

습지 전문종인 제비동자꽃(Lychnis wilfordii (Regel) Maxim.) 개체군의 내적동태

채현희 ( Hyun-hee Chae ),김영철 ( Young-chul Kim ),곽명해 ( Myoung-hai Kwak ),남기흠 ( Gi-heum Nam ) 한국환경생태학회 2021 한국환경생태학회지 Vol.35 No.3

제비동자꽃(Lychnis wilfordii (Regel) Maxim.)은 주로 고위도의 이탄습지에 분포하는 전문종이다. 우리나라에서는 2개 지역에 고립되어 분포한다. 본 연구에서는 생육지 특성, 생장특성 및 자가화합성 그리고 안정적인 개체군을 유지하고 있는 용늪습지보호지역에서 개체군의 지속에 관여하는 내적 동태를 평가하였다. 분포지의 식생환경은 용늪습지보호지역과 평창군 대관령면 분포지 사이에 뚜렷한 차이가 있었다. 화분매개충의 방문에 의해 종자의 생산이 촉진되기는 하지만 자가화합성을 함께 소유하였다. 토양의 유기물함량이 높은 조건에서 다수의 겨울눈을 생성하였고, 줄기 수, 열매 수가 최대에 달하였다. 그렇지만 유기물함량이 낮은 조건에서도 생장하고 개화하여 종자를 생산하였다. 용늪습지보호지역에서 제비동자꽃은 고층습원에는 분포하지 않았고 뚝사초가 형성하는 사초기둥이 발달한 저층습원에 분포하였다. 제비동자꽃은 이 공간에서도 사초기둥의 상단부에 주로 분포하였다. 따라서 뚝사초가 형성하는 사초기둥의 생성, 성장 및 소멸은 이 공간에 분포하는 식물의 정착, 성장, 소멸과 밀접한 연관이 있는 것으로 판단되었다. 현재 용늪습지보호지역은 제비동자꽃이 분포하는 사초기둥이 발달한 공간이 넓게 분포하고 있고 소멸과 재정착의 과정이 잘 이루어지는 것으로 평가되었다. 그러므로 현재와 같은 생태적 과정이 잘 유지된다면 용늪습지보호지역의 제비동자꽃 개체군은 오랜 기간에 걸쳐 지속 가능할 것으로 예상되었다. Lychnis wilfordii (Regel) Maxim. is one of the wetland specialists mainly distributed in peatlands at high latitudes. In Korea, it is isolated in two regions. This study investigated habitats, growth traits, and self-compatibility of L. wilfordii and assessed the internal dynamics of its population persistence. Its population has remained stable in the Yongneup Wetland Protected Area (YWPA). There was a clear difference in vegetation environment between YWPA and the distribution area in Daegwallyeong (DWL), Pyeongchang-gun. It has self-compatibility while pollinators facilitate its seed production. It produces a large number of hibernacles and bears the maximum number of branches and fruits in soil with rich organic contents. However, it grows and bears fruits even under the condition of low organic contents. In YWPA, L. wilfordii is not distributed in high moor but widely distributed in low moor where tussocks by Carex thunbergii var. appendiculata are developed. It is mainly distributed on the top of tussocks also. Therefore, it is judged that the formation, growth, and extinction of tussocks by C. thunbergii var. appendiculata is closely related to the establishment, growth, and extinction of plants distributed in this space. It is assessed that the current YWPA has well-developed tussocks in which L. wilfordii is widely distributed, and extinction and re-establishment progress well. Accordingly, the L. wilfordii population is expected to be sustainable in the long term given if its current ecological process is maintained well.

MIMO-OFDM 시스템에서 Constant Modulus 신호의 SVR-MMSE 검출 성능 분석

신철민,서명석,양청해,곽경섭,Shin, Chul-Min,Seo, Myoung-Seok,Yang, Qing-Hai,Kwak, Kyung-Sup 한국통신학회 2006 韓國通信學會論文誌 Vol.31 No.12A

본 논문에서는 MIMO 시스템에서 제안된 SVR-MMSE 검출기법을 MIMO-OFDM 시스템으로 확장, 적용하고 주파수 선택적인 채널에서 성능을 분석한다. 우선 전형적인 MIMO-OFDM 시스템에 대해서 설명하고 이 시스템에서 constant modulus 신호의 검출기법에 대하여 설명을 한다. 기존의 검출 기법인 Zero Forcing, Minimum Mean Square Error 기법과 제안된 SVR-MMSE 검출의 성능을 비교해 보고, Jakes 채널 모델을 사용하여 지연확산을 가지는 다중 경로 페이딩 채널에서 도플러 주파수가 변화함에 따라 검출 기법의 성능을 알아본다. 본 논문에서 제안된 SVR-MMSE를 이용한 MIMO-OFDM 시스템에서의 검출 성능 모의실험 결과, 제안된 알고리즘이 이 시스템에서 우수한 성능을 지니고 있음을 보여주고 있다. In this paper, we extend SVR-MMSE detection scheme which is proposed in MIMO system to MIMO-OFDM system, and evaluate performance of the system in frequency selective fading channel. First of all, we explain about typical MIMO-OFDM system and detection scheme of constant modulus signals in this system. And compare proposed SVR-MMSE with Zero Forcing, Minimum Mean Square Error which is conventional detection scheme. we identify that the performance of the proposed system is shown different by varying doppler frequency in frequency selective fading channel using jakes channel model. The result of detection performance by the proposed SVR-MMSE in this simulation, it shows that proposed algorithm have a good performance in MIMO-OFDM systems.

Estimation of micro-biota in the Upo wetland using eukaryotic barcode molecular markers

Park, Hyun-Chul,Bae, Chang-Hwan,Jun, Ju-Min,Kwak, Myoung-Hai The Ecological Society of Korea 2011 Journal of Ecology and Environment Vol.34 No.3

Biodiversity and the community composition of micro-eukaryotic organisms were investigated in the Upo wetland in Korea using molecular analysis. Molecular identification was performed using cytochrome oxidase I (COI) and small subunit ribosomal DNA (SSU rDNA). The genomic DNA was isolated directly from soil samples. The COI and SSU rDNA regions were amplified using universal primers and then sequenced after cloning. In a similarity search of the obtained sequences with BLAST in the Genbank database, the closely related sequences from NCBI were used to identify the amplified sequences. A total of six eukaryotic groups (Annelida, Arthropoda, Rotifera, Chlorophyta, Bacillariophyta, and Stramenopiles) with COI and six groups (Annelida, Arthropoda, Rotifera, Alveolata, Fungi, and Apicomplexa) with SSU rDNA genes were determined in the Upo wetland. Among 38 taxa in 20 genera, which are closely related to the amplified sequences, 10 genera (50%) were newly reported in Korea and five genera (25%) were shown to be distributed in the Upo wetland. This approach is applicable to the development of an efficient method for monitoring biodiversity without traditional taxonomic processes and is expected to produce more accurate results in depositing molecular barcode data in the near future.

In Vivo Antifungal Activities of the Methanol Extracts of Invasive Plant Species Against Plant Pathogenic Fungi

Bajpai, Vivek K.,Baek, Kwang-Hyun,Kim, Eun-Sil,Han, Jeong-Eun,Kwak, Myoung-Hai,Oh, Kyoung-Hee,Kim, Jin-Cheol,Kim, Soon-Ok,Choi, Gyung-Ja The Korean Society of Plant Pathology 2012 Plant Pathology Journal Vol.28 No.3

Plants are the promising reservoirs for natural products with their diverse secondary metabolites. Many invasive plants have been introduced in Korea, which adversely affect on the native ecosystem but holds difficulty removing them due to their proliferation. In this study, we evaluated disease control efficacy of methanol extracts from four invasive plant species against 7 representative crop pathogens. Methanol extract of Phytolacca americana effectively suppressed rice blast, tomato gray mold, and tomato late blight in a dose dependent manner. The methanol extract of Amorpha fruticosa also exhibited potent antifungal activity against pepper anthracnose in a concentration dependent way. These data suggest that the extracts of P. americana and A. fruticosa can be developed as plant disease protection agents against rice blast, tomato gray mold, tomato late blight, and pepper anthracnose. Furthermore, more extensive research will be required to identify and isolate active compounds from problematic invasive plant species to develop valuable agrochemicals.

Functional analyses of the novel salt-inducible genes from Korean halophytes

Selvam Ayarpadikannan,Eunsook Chung,Hyun-A So,Kyoung-Mee Kim,Kenneth Ryan Schraufnagle,Kim Hyo Young,Jae-Sung Kwak,Hai Yang Yu,Soon-Ok Kim,Joo-Min Jeon,Myoung-HaeKwak,Jai-Heon Lee 한국육종학회 2012 한국육종학회 심포지엄 Vol.2012 No.07

Salinity stress severely affects plant growth and development causing crop loss worldwide. Suaeda asparagoides is a salt-marsh euhalophyte widely distributed in southwestern foreshore of Korea. To isolate salt tolerance genes from S. asparagoides, we constructed a cDNA library from leaf tissues of S. asparagoides that was treated with 200 mM NaCl. A total of 1,056 clones were randomly selected for EST sequencing, and 932 of them produced readable sequence. By sequence analysis, we identified 538 unigenes and registered each in National Center for Biotechnology Information. The 80 salt stress related genes were selected to study their differential expression. Reverse Transcriptase-PCR and Northern blot analysis revealed that 23 genes were differentially expressed under the high salinity stress conditions in S. asparagoides. They are functionally diverse including transport, signal transduction, transcription factor, metabolism and stress associated protein, and unknown function. Among them dehydrin (SaDhn) and RNA binding protein (SaRBP1) were examined for their abiotic stress tolerance in yeast (Saccharomyces cerevisiae). Yeast overexpressing SaDhn and SaRBP1 showed enhanced tolerance to osmotic, freezing and heat shock stresses. This study provides the evidence that SaRBP1 and SaDhn from S.asparagoides exert abiotic stress tolerance in yeast. Information of salt stress related genes from S. asparagoides will contribute for the accumulating genetic resources to improve osmotic tolerance in plants.