• Title/Summary/Keyword: Biotic

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Macroinvertebrate Community Structure along Environmental Conditions in Ponds of Urban Parks, Korea

  • Kim, Myoung-Chul;Chun, Dong-Jun;Ro, Tae-Ho
    • Korean Journal of Ecology and Environment
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    • v.41 no.2
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    • pp.198-205
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    • 2008
  • Benthic macroinvertebrates were examined to elucidate community structures of a set of 9 shallow ponds from a total of 6 parks located in Seoul metropolitan area, Korea. The result showed that macroinvertebrates were diverse and abundant, and aquatic macrophyte provide habitat diversities in ponds. The differences among benthic macroinvertebrate community compositions seemed to be attributed to local biotic and abiotic interactions. We surveyed benthic macroinvertebrate, biotic (macrophyte), abiotic (turbidity, nutrient concentrations, conductivity, heavy metal concentration) and morphometric (area, depth) of the lentic systems. Generally, the benthic macroinvertebrates were dominated by Cloeon dipterum or Coenagrion sp.. Distribution of the aquatic macrophyte community was correlated with the species composition of macroinvertebrates. The result demonstrated a significant and positive relationship between habitat quality and macroinvertebrate composition.

A Plant Breeder's View on H5N1

  • Kim, Soon-Kwon
    • Korean Journal of Breeding Science
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    • v.40 no.2
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    • pp.106-112
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    • 2008
  • International conferences to block the spread of Avian bird flu occurred in Beijing, 2006 and others warned of the seriousness of the H5N1 strain. The meetings succeeded in generating billions of dollars from USA, EU and World Bank. Migratory birds seem to play a major role in the spread of the aggressive strain globally from Asia to Europe and Africa. Experiences of tolerance breeding of maize (Zea mays L.) for four decades against 20 biotic stresses suggest that the prime cause of the occurrence of H5N1 strain was due to the human beings' counter-efforts against nature. Excessive use of chemicals (spray and injection) in the commercial poultry farms had created high selection pressure on virus. The new strain had mutated for survival. Attempting to eliminate the virus by chemicals for 100% control is a dangerous way to control biotic stresses. This can create more aggressive strains. A solution would be to build up tolerability of the commercial animals against the virus. Improvement of poultry cage environments and respect for nature must be integrated. Potential foes must be watched.

Strategy Prospects of Environmental Restoration of Stream Side in Japan - With a Special Reference to the Forest Road, Forest Conservation and Erosion Control - (일본(日本)에서 계류변(溪流邊)의 환경복원(環境復元) 발전전략(發展戰略) II - 임도(林道) 및 치산(治山)·사방(砂防)을 중심(中心)으로 -)

  • Park, Jae-Hyeon;Woo, Bo-Myeong;Kwon, Tae-Ho;Lee, Heon-Ho
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.3 no.2
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    • pp.66-74
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    • 2000
  • This study was carried out to introduce current status and development strategy for an environmental restoration of stream side in Japan, and to consider a methodology which could be effectively applied for the environmental restoration of stream side in Korea. The strategy prospects of environmental restoration in Japan were summarized as follows: 1. We should establish a new paradigm of forest road, forest conservation and erosion control which can emphasize the restoration of the streamside ecosystem and reduce the effects of soil movement change in the areas. And we should maintain the biotic habitats to conserve native biotic community when we practice forest road, forest conservation and erosion control works. 2. In the point of view ecological conservation aspects, we should evaluate the effects of new forest conservation and erosion control methods which is emphasized on the restoration of the streamside ecosystem to apply desirable methodology to the environmental restoration of the streamside area. 3. In the past, the objective of forest conservation and erosion control was to fix a soil by construction of permanent structures. Whereas, the direction of future's forest conservation and erosion control needs to change new forest conservation and erosion control technology to prevent large scale soil movement but allow small scale soil movement to conserve sound ecosystem and biotic habitats. 4. The restoration of the streamside ecosystem should provide continuity of the streamside environment which allows desirable biological habitats, and environmentally sound facilities to harmonize the environment.

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Identification of Putative MAPK Kinases in Oryza minuta and O. sativa Responsive to Biotic Stresses

  • You, Min Kyoung;Oh, Seung-Ick;Ok, Sung Han;Cho, Sung Ki;Shin, Hyun Young;Jeung, Ji Ung;Shin, Jeong Sheop
    • Molecules and Cells
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    • v.23 no.1
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    • pp.108-114
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    • 2007
  • The mitogen-activated protein kinase (MAPK) signaling cascade is critical for regulating plant defense systems against various kinds of pathogen and environmental stresses. One component of this cascade, the MAP kinase kinases (MAPKK), has not yet been shown to be induced in plants following biotic attacks, such as those by insects and fungi. We describe here a gene coding for a blast (Magnaporthe grisea)- and insect (Nilaparvata lugens)-responsive putative MAPK kinase, OmMKK1 (Oryza minuta MAPKK 1), which was identified in a library of O. minuta expressed sequence tags (ESTs). Two copies of OmMKK1 are present in the O. minuta genome. They encode a predicted protein with molecular mass 39 kDa and pI of 6.2. Transcript patterns following imbibition of plant hormones such as methyl jasmonic acid (MeJA), ethephone, salicylic acid (SA) and abscisic acid (ABA), as well as exposure to methyl viologen (MV), revealed that the expression of OmMKK1 is related to defense response signaling pathways. A comparative analysis of OmMKK1 and its O. sativa ortholog OsMKK1 showed that both were induced by stress-related hormones and biotic stresses, but that the kinetics of their responses differed despite their high amino acid sequence identity (96%).

Characterization of a Stress-Responsive Ankyrin Repeat-Containing Zinc Finger Protein of Capsicum annuum (CaKR1)

  • Seong, Eun-Soo;Choi, Do-Il;Cho, Hye-Sun;Lim, Chun-Keum;Cho, Hye-Jeong;Wang, Myeong-Hyeon
    • BMB Reports
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    • v.40 no.6
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    • pp.952-958
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    • 2007
  • We isolated many genes induced from pepper cDNA microarray data following their infection with the soybean pustule pathogen Xanthomonas axonopodis pv. glycines 8ra. A full-length cDNA clone of the Capsicum annuum ankyrin-repeat domain $C_3H_1$ zinc finger protein (CaKR1) was identified in a chili pepper using the expressed sequence tag (EST) database. The deduced amino acid sequence of CaKR1 showed a significant sequence similarity (46%) to the ankyrin-repeat protein in very diverse family of proteins of Arabidopsis. The gene was induced in response to various biotic and abiotic stresses in the pepper leaves, as well as by an incompatible pathogen, such as salicylic acid (SA) and ethephon. CaKR1 expression was highest in the root and flower, and its expression was induced by treatment with agents such as NaCl and methyl viologen, as well as by cold stresses. These results showed that CaKR1 fusion with soluble, modified green fluorescent protein (smGFP) was localized to the cytosol in Arabidopsis protoplasts, suggesting that CaKR1 might be involved in responses to both biotic and abiotic stresses in pepper plants.

The Correlation between Water Quality and Benthic Macroinvertebrate Community Indices in the Jinwi Stream (진위천의 수질과 저서성 대형무척추동물 군집지수의 상관관계)

  • Choi, Ah-Reum;Park, Sun-Jin;Kim, Jin-Young;Song, Mee-Young;Kong, Dong-Soo
    • Korean Journal of Ecology and Environment
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    • v.45 no.1
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    • pp.1-10
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    • 2012
  • The Jinwi stream, which is located in the Gyeonggi Province, shows a large variation in water quality from the upper stream to downstream. Therefore the Jinwi stream is suitable for assessing changes to the benthic macroinvertebrate community structure according to saprobity. This study was conducted to find out the applicability of biotic indices for water quality pollution through an analysis of the correlation between water quality and benthic macroinvertebrate indices for the Jinwi stream. Along with the pollution of water, the species composition of Ephemeroptera decreased, while that of Annelida increased. The ecological score for the benthic macroinvertebrate community (ESB) showed more significant correlations than any other biotic index (H', DI, R1, J, EPT and KSI) with the water quality items.

Morphological Classification of Trichomes Associated with Possible Biotic Stress Resistance in the Genus Capsicum

  • Kim, Hyun-Jung;Seo, Eun-Young;Kim, Ji-Hyun;Cheong, Hee-Jin;Kang, Byoung-Cheorl;Choi, Do-Il
    • The Plant Pathology Journal
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    • v.28 no.1
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    • pp.107-113
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    • 2012
  • Trichomes are specialized epidermal structure having the functions of physical and chemical block against biotic and abiotic stresses. Several studies on $Capsicum$ species revealed that virus and herbivore resistance is associated with trichome-formation. However, there is no research on the structural characterization of trichomes developed on the epidermis of $Capsicum$ spp. Thus, this study attempts to charaterize the trichome morphologies in 5 species of $Capsicum$ using a Field Emission Scanning Electron Microscopy (FESEM). Six main trichome types were identified by their morphology under FESEM. Both glandular and non-glandular types of trichomes were developed on the epidermal tissues of $Capsicum$ spp. The glandular trichome were further classified into type I, IV and VII according to their base, stalk length, and stalk. Non-glandular trichomes were also classified into type II, III, and V based on stalk cell number and norphology. Almost all the species in $C.$ $chinense$ and $C.$ $pubescens$ had glandular trichomes. To our knowledge, this is the first study on classification of trichomes in the genus $Capsicum$ and, our results could provide basic informations for understanding the structure and function of trichomes on the epidermal differentiation and association with biotic stress tolerance.

Revision of Ecological Score of Benthic Macroinvertebrates Community in Korea (한국의 저서성 대형무척추동물 생태점수 개선)

  • Kong, Dongsoo;Park, Youngjun;Jeon, Yong-Rak
    • Journal of Korean Society on Water Environment
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    • v.34 no.3
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    • pp.251-269
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    • 2018
  • In 1997, the environmental score (Q) corresponding the tolerance value of Korean benthic macroinvertebrate species and the related biotic score, the ecological score of benthic macroinvertebrates (ESB) were proposed; ESB was similar to Beck's biotic index or Chandler's biotic score. This study was carried out to revise the Q values of individual species and the assessment scheme of ESB based on the taxonomic performance and ecological information accumulated since then. The original ESB was renamed as TESB (total ESB), and AESB (average ESB) was newly proposed. AESB is calculated by dividing the TESB (for a given station) by the number of species present in the sample. In this study, TESB showed a positively skewed distribution, while AESB showed a negatively skewed distribution. The correlation between TESB and the concentration of $BOD_5$ was a little stronger than that of the original ESB. TESB showed a very strong correlation (correlation coefficient r = 0.98) with Margalef's species richness, of which correlation coefficient was higher than that of AESB (r = 0.85). AESB showed a strong correlation (r = -0.79) with the concentration of $BOD_5$, while TESB showed a weaker correlation (r = -0.67). Applying TESB and AESB together in an assessment of the environment may be comprehensive because the physical and chemical states of the environment can be evaluated together. AESB is less dependent on the sample size, while TESB tends to increase as the sample size increases. In the evaluation of the environment using TESB, it is necessary to standardize the methods on monitoring.