• Journal of Ecology and Environment
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• 제36권3호
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• pp.167-172
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• 2013

A Two-year field experiment was carried out in 2009 and 2010 to evaluate the effects of different densities of wild oat and nitrogen (N) rates on oilseed rape yield and yield components. Experimental design was split plot with three replications. Increased nitrogen rates up to 150 kg N/ha caused an increase in oilseed rape grain yield in weed-free plots (4.26 t/ha; 1t = $10^3kg$), while even at the lowest density of wild oat (15 $plants/m^2$), increasing N fertilizer only up to 50 kg/ha led to a significant increase in grain yield. Wild oat growth was favored by high levels of N. Intraspecific competition reduced biomass, 100-seed weight and number of tillers of wild oat. Both lower N rate and intraspecific competition had negative effect on wild oat growth but the weed was still able to produce a considerable number of tillers and vigorous seeds. It showed that wild oat possess a notable adaptive plasticity and can allocate a greater proportion of its resource toward reproductive organs even under resource shortage conditions and, thus, it may increase the competitive ability of the weed over the crop.Our results suggest that effective weed management should be done to prevent wild oat seed production in crops preceding oilseed rape as well as to control the weed at early season in oilseed rape fields.

• Journal of Plant Biology
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• 제4권1호
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• pp.1-7
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• 1961

분류학에서 이종으로 취급되고 있는 Forsythia속의 종간교잡을 실시하여 화주장의 분리비, 양화주간의 수정양식, $F_1$의 임성, ♀♂성 기타 분류학상의 제문제제를 구명한바 그 요지는 다음과 같다. (1) 화주장은 L:S=1:1로 분리한다. (2) 이종간의 적, 부적법수분인데도 양친 L, S의 수정양식은 일 일반형예식물 동일종내의 2형화와 전혀 동일하다. (3) $F_1$의 L, S간의 수정양식도 일반형예식물과 동일하다. (4) 종간교잡은 잘되고 $F_1$의 임성도 이상없다. (5) 교잡제일식의 형태, 생리적변이는 심하다. (6) S주도 적법수분에서는 임성이 양호하고 Forsythia가 ♀, ♂ 이주라는 것은 잘못이다. (7) $F_1$에는 영양생장 및 생식기관이 빈약한 왜형이 나타난다. (8) 본실험에 사용한 두종은 이종이라기보다 동일종내의 이화형개체라고 하는 것이 타당하다.

• 한국약용작물학회지
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• 제10권1호
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• pp.12-16
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• 2002

약용작물은 재배환경, 재배방법, 생육 시기 및 부위별로 약리성분 함량에 차이가 많은데, 이뇨, 진통, 지혈, 조직재생 및 혈관확장 등의 약리효과가 있다고 보고된 어성초를 생육 시기별, 부위별 및 퇴비 시용량별로 유효성분 함량을 분석한 결과는 다음과 같다. 생육 시기별 quercetin 및 tannin 함량은 생육 초기인 4월 20일에 채취하였을 때 각각 0.72, 2.1%로 함량이 가장 높았으며, 개화기 전까지 감소하다가 개화기 이후로 증가하였다. 부위별 quercetin 및 tannin 함량은 꽃에서 2.06, 5.3%로 가장 높았으며, 잎, 줄기, 뿌리 중에서는 잎에서 각각 0.81 및 2.3%로 높았다. 퇴비 시용량별 어성초의 quercetin 및 tannin함량은 무처리구에서 각각 0.67 및 2.3%로 가장 높았고, 퇴비시용량이 증가할 수록 지상부 수량은 증가하였으나 유효성분 함량은 감소하였다.

• Journal of Plant Biotechnology
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• 제34권3호
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• pp.173-180
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• 2007

The full-length cDNA of LeAPR1 encoded a protein of 461 amino acid residues, which contained homology with phosphoadenosine phosphosulphate reductase (PAPS reductase) in N-terminal and an adenylylsulfate reductase in N-term and C-terminal. Analysis of the deduced amino acid sequence of LeAPR1 revealed that it shares high sequence identity with potato StAPR (96% identity)(Gene bank accession no. CDC44841). We found that multiple copies of LeAPR1 gene are present in the tomato genome through southern blot using genomic DNA was digested with 3 different restriction enzymes. The expression of LeAPR1 was also examined in various organs and its expression was also detected at high levels in roots and stems. Only high amounts of LeAPR1 transcripts were detected at high transcripts in the leaves at time 0, and then reduced as the plant stressed by the NaCl and abscisic acid (ABA). After 24h treatment of NaCl and ABA were showed increasing patterns of LeAPR1 gene. Time course of LeAPR1 gene expression was examined under oxidative stresses from metyl viologen (MV) and hydrogen peroxide ($H_2O_2$). In the presence of 10 mM $H_2O_2$ and $50\;{\mu}M$ MV, the levels of LeAPR1 transcript in leaves decreased after 1 h, and then increased strongly, peaked at 24 h. Our results indicated that LeAPR1 may play a role function of circadian regulation involved in abiotic stresses signaling pathways.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2018년도 춘계학술대회 및 임시총회
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• pp.13-13
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• 2018

Alternaria is a ubiquitous fungal genus, widely distributed in the environment and a range of different habitats. It includes both plant pathogenic and saprophytic species, which can affect crops in the field or cause post-harvest spoilage of plant fruits and kernels. Numerous Alternaria species cause damage to agricultural products including cereal grains, fruits and vegetables, and are responsible for severe economic losses worldwide. Most Alternaria species have the ability to produce a variety of secondary metabolites, which may play important roles in plant pathology as well as food quality and safety. Alternariol (AOH), alternariol monomethyl ether (AME), tenuazonic acid (TeA), tentoxin (TEN) and altenuene (ALT) are considered the main Alternaria compounds thought to pose a risk to human health. However, food-borne Alternaria species are able to produce many additional metabolites, whose toxicity has been tested incompletely or not tested at all. Both alternariols are mutagenic and their presence in cereal grain has been associated with high levels of human esophageal cancer in China. TeA exerts cytotoxic and phytotoxic properties, and is acutely toxic in different animal species, causing hemorrhages in several organs. The possible involvement of TA in the etiology of onyalai, a human hematological disorder occurring in Africa, has been suggested. Altertoxins (ALXs) have been found to be more potent mutagens and acutely toxic to mice than AOH and AME. Other metabolites, such as TEN, are reported to be phytotoxins, and their toxicity on animals has not been demonstrated up to now. Vegetable foods infected by Alternaria rot are obviously not suitable for consumption. Thus, whole fresh fruits are not believed to contribute significantly with Alternaria toxins to human exposure. However, processed vegetable products may introduce considerable amounts of these toxins to the human diet if decayed or moldy fruit is not removed before processing. The taxonomy of the genus is not well defined yet, which makes it difficult to establish an accurate relationship between the contaminant species and their associated mycotoxins. Great efforts have been made to organize taxa into subgeneric taxonomic levels, especially for the small-spored, food associated species, which are closely related and constitute the most relevant food pathogens from this genus. Several crops of agricultural value are susceptible to infection by different Alternaria species and can contribute to the entry of Alternaria mycotoxins in the food chain. The distribution of Alternaria species was studied in different commodities grown in Argentina. These food populations were characterized through a polyphasic approach, with special interest in their secondary metabolite profiles, to understand their full chemical potential. Alternaria species associated with tomato, bell pepper, blueberry, apples and wheat cultivated in Argentina showed a surprisingly high metabolomic and mycotoxigenic potential. The natural occurrence of Alternaria toxins in these foods was also investigated. The results here presented will provide background for discussion on regulations for Alternaria toxins in foods.

• Journal of Ginseng Research
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• 제33권1호
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• pp.59-64
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• 2009

$Ca^{2+}$ and calmodulin (CaM), a key $Ca^{2+}$ sensor in all eukaryotes, have been implicated for defense responses of plants. Eukaryotic CaM contains four structurally and functionally similar $Ca^{2+}$ domains named I, II, III and IV. Each $Ca^{2+}$ binding loop consists of 12 amino acid residues with ligands arranged spatially to satisfy the octahedral symmetry of $Ca^{2+}$ binding. To investigate the altered gene expression and the role of CaM in ginseng plant defense system, cDNA clone containing a CaM gene, designated PgCaM was isolated and sequenced from Panax ginseng. PgCaM, which has open reading frame of 450 nucleotides predicted to encode a precursor protein of 150 amino acid residues. Its sequence shows high homologies with a number of other CaMs, with more similarity to CaM of Daucus carota (AAQ63461). The expression of PgCaM in different P. ginseng organs was analyzed using real time PCR. The results showed that PgCaM expressed at different levels in young leaves, shoots, and roots of 3-week-old P. ginseng. In addition, the expressions of PgCaM under different abiotic stresses were analyzed at different time intervals.

• 식물조직배양학회지
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• 제24권1호
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• pp.1-35
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• 1997

Fertilized egg, by successive cell divisions, differentiates into different tissues and organs with various structures and functions. Different cells and tissues contain different proteins, products of selective gene expression. Not all the genes in any genomes are equally active, temporal and spatial gene expression being the general rule. Present paper attempts to review the tanscriptional mechanisms or the initiations of transcription from several angles. In some of the organisms the genes in the process of transcription or the genes in the inactive state can be seen under the light microscope. Some bands of Drosophila polytene chromosomes may exhibit a swollen or puff appearance under certain conditions. A puff, unfolded or decondensed form of chromomere, represents sets of intense transcriptional activity or RNA synthesis. The heterochromatic X chromosome whose genes remain inactive in the female mammals can be visualized as a dark staining structure called Barr body, Configuration of chromatin differs between transcribed and nontranscribed chromatin. Modification to the chromatin facilitates RNA synthesis. The movement of large polymerase molecule along the DNA would probably be facilitated if some modifications of the chromatin configuration is effected. Methylation of cytosines in CG sequences is associated with inactive genes. Methylation can play a role in determination of mammalian cells during embryogenesis. Demethylation is necessary for the gene to be expressed during development A histone modification that is also known to be correlated with transcriptional capacity of chromatin is acetylation of the lysine residues of the core histones. Chromatin containing a high level of histone acetylation is very sensitive to DNase 1. For the transcription to occur TBP must first bind to the TATA box. Another TF, TF IIB, then binds to the promoter-TBP complex, facilitating the access of RNA polymerase to the transcription initiation site. As recently as eight years ago researchers assumed that histones were irrelevant to the regulation of gene expression. Histones combine with the DNA to form nucleosome of the chromatin. Histones are vital participant in gene regulation. Histone and basal factors compete for access to TATA box. When DNA is exposed to basal factors before histones are introduced, the basal factors assemble on TATA boxes preventing the access of histones, allowing transcription to occur, for transcription to begin, activator protein at the upstream activation sequence or enhancer must interact with the tail of histone H4 at TATA box and cause the histone role particle to dissociate from the TATA box leading to partial breakup of the histone core particle and allowing the basal factors to bind to the TATA box. New concept of genomic flux in contrast to the old concept of static genome has been developed based on the powerful new molecular techniques. Genomic changes such as repetitive DNAs and transposable elements, it is assumed but not yet proved, may affect some of the developmental patterns that characterize particular cells, tissues, organs, and organisms. In the last decade or so remarkable achievement have been made in the researches of the structures and functions of TFs and the specific target sequences located in promoters or enhancers where these TFs bind. TFs have independent domains that bind DNA and that activate transcription. DNA binding domain of TFs serves to bring the protein into the right location. There are many types of DNA binding domains. Common types of motifs can be found that are responsible for binding to DNA. The motifs are usually quite short and comprise only a small part of the protein structure. Steroid receptors have domains for hormone binding, DNA binding, and activating transcription. The zinc finger motif comprises a DNA binding domain. Leucine zipper consist of a stretch of amino acids with a leucine residue in every seventh position Two proteins form a dimer because they interact by means of leucine zippers on similar α-helical domain. This positions their DNA binding basic domains for interaction with the two halves of a DNA sequence with dyad symmetry of TGACTCA, ACTGAGT.

• Journal of Plant Biotechnology
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• 제42권4호
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• pp.370-375
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• 2015

스프레이국화 '퍼플엔디'의 꽃잎을 이용하여 부정아유기에 효율적인 부정아 유기조건을 찾기 위하여 실시하였다. 배양재료로 사용한 꽃잎은 꽃봉오리의 개화진전단계(S1; 10% 개화, S2; 30% 개화, S3; 50% 개화, S4; 70% 개화)를 4단계로 하고 꽃잎부위는 꽃잎의 기부와 끝부분(TBOP; the basal of petal, TEOP; the end of petal)으로 나누어 MS무기염에 IAA와 BAP를 첨가한 배지에 배양하였다. 배양재료는 30% 정도 개화가 진전(S2)되었을 때 꽃잎을 채취하여 꽃잎을 하나씩 분리한 후 꽃잎 중간 길이에서 가로로 잘라서 꽃잎 끝부분(TEOP)을 사용하고 $1.0mg{\cdot}L^{-1}$ IAA와 $2.0mg{\cdot}L^{-1}$ BAP의 농도로 첨가한 MS배지에 치상하였을 때 79.2%의 부정아 형성과 33.4개의 유묘를 획득할 수 있었다. 재분화된 식물체의 배수성 분석결과 모본과 동일하였으며 온실에서 순화 후 정상적인 생육과 개화를 확인할 수 있었다.

• 환경생물
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• 제27권4호
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• pp.406-413
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• 2009

The enzyme invertase contributes to sugar unloading, pathogen defense, differentiation and development in plants. We cloned the complete cDNA of a soluble acid invertase from pea seedlings (Pisum sativum) via RT-PCR and the rapid amplification of the cDNA end (RACE) technique. The full-length cDNA of the soluble pea invertase comprised 2237 bp and contained a complete open reading frame encoding 647 amino acids. The deduced amino acid sequence showed high homology to soluble acid invertases from various plants. Northern blot analysis demonstrated the soluble acid invertase gene of P. sativum was strongly expressed in sink organs such as shoot tips and root tips, and induced by abscisic acid, gibberellic acid and jasmonic acid in shoots. Especially, gibberellic acid enhanced the gene expression of the soluble acid invertase in a time-dependent manner. This study presents that the gene expression patterns of a soluble acid invertase from pea are strongly consistent with the suggestion that individual invertase gene product has different functions in the growing plant.

• 한국작물학회지
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• 제66권4호
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• pp.452-458
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• 2021

뿌리는 식물에서 양분과 수분을 흡수하는 가장 중요한 기관임에도 불구하고 분석방법에 어려움으로 인해 지상부에 비해 연구가 상대적으로 미비한 실정이다. 최근 이미지를 기반으로 작물의 표현형을 분석하는 기술이 급격하게 발달하고 있으며, 뿌리 연구에 있어서도 이미지를 다양하게 활용하고 있다. 뿌리분석은 목적에 따라 토양에서 분리 후 측정하는 방법과 토양에서 바로 측정하는 방식이 있으며, 각각의 방식들마다 장점과 단점이 있으므로 연구자의 상황에 맞게 활용할 수 있다. 이런 이유에서 본 리뷰에서는 이미지를 활용한 뿌리분석 방법들에 대해 소개하여 국내 연구자들의 뿌리 연구에 이용되기를 바란다.