• 농업기술회보
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• v.52 no.4
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• pp.12-13
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• 2015

일반적으로 식물은 생장 중에 많은 양의 생체 방어 물질이 자체적으로 생성되지만, 건실한 성장 후에 생체 방어 물질은 급격하게 소멸되거나 감소한다. 이에 식물체에 저농도 자외선(Ultraviolet(UV) Radiation)을 처리하면 스트레스 또는 DNA의 손상이 유도되며 이에 대응하여 식물체는 항상성(Homeoslasis)을 유지하기 위한 긍적적인 변화를 일으킨다. 농촌진흥청에서는 마늘에 저농도 자외선을 처리해 저장성 기능성 성분을 높이는 기술을 개발했다.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.143-154
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• 2022

Plant secondary metabolites play an important role in insect-plant interactions. Herbivorous insects have various strategies to cope with the plant defensive compounds. Polyphagous insects feed on a wide variety of plant species, and their detoxification mechanisms are more complex since they tend to respond to a large array of different plant-derived chemicals. Alternatively, oligophagous insects specialize on only a few related plant species and may be expected to have a more efficient form of adaptation. This adaptation could involve either the production of large quantities of enzymes to detoxify their defensive compounds or the sequestration of the compounds or their metabolites. The oriental tobacco budworm, Helicoverpa assulta, is a specialist herbivore, feeding on a few plants of Solanaceae, such as tobacco and hot pepper. Understanding its host-plant adaptation not provides an important insight on physiology, ecology and evolution of specialist herbivores, but also gives a clue to develop management strategies of the pest species such as H. assulta. This paper briefly reviews the specialist, H. assulta, focusing on its host range, larval associations with the host plants, and detoxification mechanisms to nicotine and capsaicin, two characteristic defensive compounds derived from its two major host plants, tobacco and hot pepper, respectively. It summarizes the relevant research over the last half century and provides a future perspective on this subject.

• 대한방사선방어학회:학술대회논문집
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• 2011.04a
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• pp.116-117
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• 2011

• Korean Journal of Organic Agriculture
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• v.30 no.3
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• pp.393-407
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• 2022

The effect of Neobacillus sp. JC05 extract on the defense response in cucumber plants against root-knot nematode (RKN) was evaluated. As a result of drench treatment of JC05-extract in cucumber plants, formation of egg mass per plants and disease severity were significantly decreased compared to untreated control plants; the malondialdehyde contents also decreased in JC05-extract treated plants. When eggs of Meloidogyne incognita were inoculated, cucumber plants treated with JC05-extract elevated pathogenesis-related gene expression such as chitinase and lipoxygenase, these are well known as inducing resistance in plants, in addition, peroxidase among antioxidant enzymes was significantly activated. Moreover, the JC05-extract enhanced FDAse activity in soils grown cucumber plants inoculated by eggs of M. incognita. Taken together, these results suggest that the JC05-extract could involve in activation of defense-related mechanisms of cucumber plants and result in decrease of disease occurrence caused by M. incognita.

• Journal of Radiation Protection and Research
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• v.25 no.1
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• pp.37-43
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• 2000

Protective effect of medicinal plant extracts against oxidative stress were screened in this study. Methanol extracts from 48 medicinal plants, which were reported to have antioxidative or anti-inflammtory effect were prepared and screened for their protective activity against chemically-Induced and radiation-induced oxidative stress by using MTT assay. Thirty three samples showed protective activity against chemically-induced oxidative stress in various extent Among those samples, extract of Glycyrrhiza uralensis revealed the strongest activity (25.9% at $100{\mu}g/m{\ell}$) with relatively lower cytotoxicity. Seven other samples showed higher than 20% protection at $100{\mg}g/m{\ell}$. These samples were tested for protection activity against radiation-induced oxidative stress. Methanol extract of Alpina officinarum show the highest activity (17.8% at $20{\mu}g/m{\ell}$). Five fractions were prepared from the each 10 methanol extracts which showed high protective activity against oxidative stress. Among those fraction samples butanol fractions of Areca catechu var. dulcissima and Spirodela polyrrhiza showed the highest protective activities (78.8% and 77.2%, respectively, at $20{\mu}g/m{\ell}$).

• Korean Journal of Plant Resources
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• v.34 no.4
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• pp.362-367
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• 2021

Ginger roots are widely used as spices in various foods and herbal medicine due to its characteristic flavor and biological activity. In this study, the protective effect of aged ginger extracts against oxidative stress were investigated using L6 muscle cells. As the results, aged ginger extracts significantly inhibited oxidative stress induced muscle cell damage. The protective effect of aged ginger extracts was higher than non-aged ginger extract. Aged ginger extracts also inhibited the increase in LDH, lactate and GOT in the mouse blood induced by excessive running exercise. Therefore, aged ginger is considered to be effective for protecting excessive exercise stress.

• Landscaping Tree
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• s.102
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• pp.26-28
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• 2008

최근 환경변화와 국제교류의 확대로 인하여 예전에는 문제가 되지 않았거나, 보이지 않았던 해충들이 문제해충화 되어 우리 주변에서 정원수나 조경수에 피해를 주는 해충들이 있다. 이들은 크게 3가지로 분류되는데 (1)환경의 변화에 의한 잠재해충과 문제해충화 (2) 인간의 욕심에 의해 대면적 식재로 인한 해충의 기회 확대 (3) 국제교류 확대로 인한 외래 해충의 침입 으로 나눌 수 있다. 이번 호에서는 환경변화에 의한 해충의 발생으로 환경스트레스에 의해 식물 자체 내의 방어체계가 무너지면 어떤 특정종이나 일반 해충이 대발생하는데 식물자체 환경 스트레스에 관계하는 jasmonate의 작용 저해, 식물이 자기방어를 위해 분비하는 타감물질(allelopathy)의 분비 억제, 초식성 곤충으로부터 산란억제를 위한 연모의 부족 등 해충의 대발생을 야기 시키는 경우도 있다. 또한 지구온난화로 인한 각종 해충의 대발생은 현재 전 세계적으로 문제가 되고 있다. 기온의 상승으로 곤충의 발육이 빨라져 화기 수가 증가한다거나, 포식자와 피식자의 상호작용의 연결고리가 깨어지는 등 각종 원인으로 인한 최근 발생한 해충을 기술하였다.

• Bioindustry News
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• v.14 no.1
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• pp.15-19
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• 2001

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2011.04a
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• pp.31-33
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• 2011

화외밀선(EFN)의 형태로 엽연부의 엽맥 끝에 넥타를 분비하는 것은 가막살나무 5 수종에서 모두 관찰되었다. 가막살나무, 산가막살나무에서는 잎 뒷면 선점(pellucid dot)이 분포하는 것이 좋은 방어전략이라 판단된다. 가막살나무의 선점에서 넥타를 먹는 포식응애들이 다수 관찰되었다. 분꽃나무의 잎 뒷면에는 성모 이외에 별모양의 부드러운 털이 있으며, 이를 포식응애가 먹는 것이 관찰되었으며, 이 구조가 가막살나무, 산가막살나무에서의 선점과 같은 역할일 것이라 추정되나 좀더 정밀한 연구가 필요할 것이라 판단된다. 수종별로 독특한 방법으로 초식에 대한 방어전략을 개발하면서 꾸준히 진화하고 있다고 판단된다. 여기에 화학적 방어전략이 추가된다면 식물이 살아남기 위하여 얼마나 열심히 노력하고 있는가를 어느 정도 이해할 수 있을 것이라 기대된다.

• Journal of Plant Biotechnology
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• v.33 no.2
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• pp.93-97
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• 2006

The calmodulin as a Ca$^{2+}$-binding protein mediates cellular Ca$^{2+}$ signals in response to a wide array of stimuli in higher eukaryotes. Plants produce numerous calmodulin isoforms that exhibit differential gene expression patterns and sense different Ca$^{2+}$ signals. SCaM-5 is a soybean calmodulin that is involved in plant defense signaling. Here, we constructed a SCaM-5 CDNA under control of CaMV 35S promoter and transformed it into tomato (Lycopersicon esculentum). The constitutive over-expression of SCaM-5 in tomato plants exhibited a high levels of pathogenesis-related (PR) gene expression, and conferred an enhanced resistance to two fungal pathogen (Phytophthora capsici, Fusarium oxysporum), and a bacterial pathogen, Pseudomonas syringae pv. tomato DC3000. Thus, this results collectively suggest that SCaM-5 plays an important role in plant defense of tomato.