• 한국환경농학회지
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• 제17권2호
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• pp.182-188
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• 1998

화삼회토양에서 감귤대목으로 사용되는 탱자 유모의 생육에 미치는 arbuscular mycorrhizae(AM)의 영향을 조사하기 위하여, N, P, K 시비수준을 달리한 화산회토에서 감귤뿌리를 접종 재료로 하여 AM균을 접종시킨 탱자 유묘를 재배하였다. 유모의 생육과 식물체내 무기 함량을 분석하고 감염된 화분토양에서 채취한 포자의 종류를 동정하였다. 토양 5L당 21-17-17 복비 40g과 용성인비 50g을 준 다비인산구에서만 감염된 화분의 비율이 70%였고 나머지 인산을 첨가하지 않거나 시비량이 적은 처리들에서는 감염 비율이 20% 이하였다. AM 형성율의 증가에 따라 지상부의 생채중과 건물중은 유의하게 증가 되었으며, 초장과 지하부 생채중 및 건물도 5% 수준에서 유의성은 인정되지 않았지만 증가하는 경향이었다. 따라서 식물체 내의 P와 Cu, Mg의 함량은 AM 형성율의 증가에 따라 비례적으로 유의하게 증가하였으며, N과 Zn의 함량도 증가하지만 Ca 함량은 감소하는 경향이었다. 접종 재료를 채취한 토양에서 발견되는 Glomus desertcola, G. rubiforme, G. vesiculiferm 과 Acaulospora sp. 등 4종의 AM균 포자 모두가 접종된 화분토양에서도 확인되어 이들 균이 모두 탱자 뿌리에서 AM을 형성하는 것으로 판단되었다. 토양중의 인산 수준이 감귤 뿌리의 AM균 감염을 결정하는 요인으로 작용하는 것 같으며 감귤원에서 AM을 효과적으로 이용하기 위해서는 우선 AM의 형성율을 높일 수 있는 적정 토양 인산 수준에 대한 연구가 이루어져야 할 것이다.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2015년도 추계학술대회 및 정기총회
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• pp.41-41
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• 2015

Oomycetes belong to the kingdom Straminipila, a remarkably diverse group which includes brown algae and planktonic diatoms, although they have previously been classified under the kingdom Fungi. These organisms have evolved both saprophytic and pathogenic lifestyles, and more than 60% of the known species are pathogens on plants, the majority of which are classified into the order Peronosporales (includes downy mildews, Phytophthora, and Pythium). Recent phylogenetic investigations based on DNA sequences have revealed that the diversity of oomycetes has been largely underestimated. Although morphology is the most valuable criterion for their identification and diversity, morphological species identification is time-consuming and in some groups very difficult, especially for non-taxonomists. DNA barcoding is a fast and reliable tool for identification of species, enabling us to unravel the diversity and distribution of oomycetes. Accurate species determination of plant pathogens is a prerequisite for their control and quarantine, and further for assessing their potential threat to crops. The mitochondrial cox2 gene has been widely used for identification, taxonomy and phylogeny of various oomycete groups. However, recently the cox1 gene was proposed as a DNA barcode marker instead, together with ITS rDNA. To determine which out of cox1 or cox2 is best suited as universal oomycete barcode, we compared these two genes in terms of (1) PCR efficiency for 31 representative genera, as well as for historic herbarium specimens, and (2) in terms of sequence polymorphism, intra- and interspecific divergence. The primer sets for cox2 successfully amplified all oomycete genera tested, while cox1 failed to amplify three genera. In addition, cox2 exhibited higher PCR efficiency for historic herbarium specimens, providing easier access to barcoding type material. In addition, cox2 yielded higher species identification success, with higher interspecific and lower intraspecific divergences than cox1. Therefore, cox2 is suggested as a partner DNA barcode along with ITS rDNA instead of cox1. Including the two barcoding markers, ITS rDNA and cox2 mtDNA, the multi-locus phylogenetic analyses were performed to resolve two complex clades, Bremia lactucae (lettuce downy mildew) and Peronospora effuse (spinach downy mildew) at the species level and to infer evolutionary relationships within them. The approaches discriminated all currently accepted species and revealed several previously unrecognized lineages, which are specific to a host genus or species. The sequence polymorphisms were useful to develop a real-time quantitative PCR (qPCR) assay for detection of airborne inoculum of B. lactucae and P. effusa. Specificity tests revealed that the qPCR assay is specific for detection of each species. This assay is sensitive, enabling detection of very low levels of inoculum that may be present in the field. Early detection of the pathogen, coupled with knowledge of other factors that favor downy mildew outbreaks, may enable disease forecasting for judicious timing of fungicide applications.

• Environmental Analysis Health and Toxicology
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• 제12권3_4호
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• pp.31-41
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• 1997

Public concerns about hazardous health effect from the exposure to organic by-products of the chlorination have been increased. There are numerous studies reporting that chlorination of drinking water produces numerous chlorinated organic by-products including THMs, HAAs, HANs. Some of these products are known to be animal carcinogens. The purpose of this study was to estimate health risk of DBPs by chlorinated drinking water ingestion in Seoul based on methodologies that have been developed for conducting risk assessment of complex-chemical-mixture. The drinking water sample was collected seperately at six water treatment plant in Seoul at March, April, 1996. In tap water of households in Seoul, DBPs were measured wilfh the mean value of 36.6 $\mu$g/L. Risk assessment processes,. which include processes for the estimation of human cancer potency using animal bioassay data and calculation of human exposure, entail uncertainties. In the exposure assessment process, exposure scenarios with various assumptions could affect the exposure amount and excess cancer risk. The reference dose of haloacetonitriles was estimated to be 0.0023 mg/kg/day by applying dibromoacetonitrile NOAEL and uncertainty factor to the mean concentration. In the first case, human excess cancer risk was estimated by the US EPA method used to set the MCL (maximum contaminant level). In the second and third case, the risk was estimated for multi-route exposure with and without adopting Monte-Carlo simulation, respectively. In the second case, exposure input parameters and cancer potencies used probability distributions, and in the third case, those values used point estimates (mean, and maximum or 95% upper-bound value). As a result, while the excess cancer risk estimated by US EPA method considering only direct ingestion tended to be underestimated, the risk which was estimated by considering multi-route exposure without Monte-Carlo simulation and then using the maximum or 95% upper-bound value as input parameters tended to be overestimated. In risk assessment for Trihalomethanes, considering multi-route exposure with adopting Monte-Carlo analysis seems to provide the most reasonable estimations.

• 한국가스학회지
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• 제20권4호
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• pp.7-14
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• 2016

최근 북한은 경제난으로 인해 에너지 부문의 투자여력이 감소되었고 에너지 부문의 투자 감소는 다시 에너지 생산 감소라는 악순환이 반복되고 있다. 이런 상황을 살펴볼 때 북한의 경제상황이 나아지게 된다면 우선적으로 투자될 부문은 에너지부문이라 판단된다. 본 논문에서는 개성공단 내 천연가스 복합화력발전소 건설에 3,900억 원이 투자 되었다고 가정하고 북한경제와 남한경제에 미치는 경제적 파급효과를 계산하였다. 북한의 경제적 파급효과를 분석하기 위하여 2014년도 산업연관표(북한)를 작성하였고, 투입-산출모형을 이용하였다. 천연가스산업 투자의 파급효과는 10.12억 달러이다. 또한, 남한의 경제에 미치는 파급 효과를 분석하기 위해 2013년 산업연관표(남한)와 산업연관분석의 수요유도형 모형을 이용하였다. 천연가스산업 투자의 생산유발효과, 부가가치유발효과, 취업유발효과는 각각 2.02073, 0.62697, 8.99409으로 계산되었다.

• 동아시아식생활학회지
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• 제17권2호
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• pp.205-212
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• 2007

This study was designed to investigate a natural medicinal multi-plants extract (BG515), which consisted of multi extracts of Mori folium, Rehmannia glutinosa Liboschitz, Dioscorea japonica, Lycii fructus, and Astragalus radix, on blood glucose, insulin levels, and serum malondialdehyde (MDA) concentrations in streptozotocin-induced diabetic rats. Streptozotocin (STZ) induces a type 1 diabetes mellitus in rats. Type 1 is usually characterized by the presence of islet cell autoantibodies (ICA), autoantibodies to insulin (IAA), and autoantiboides to glutamic acid decarboxylase (GAD), which identify the autoimmune process that leads to $\beta-cell$ destruction. Thirty-five male Sprague-Dawley (SD) rats weighing $150\sim170g$ each (6 weeks old) were randomly divided into one control (Group A) and 4 STZ-induced diabetic groups, and were subjected to one of the following treatment for 12 weeks. Groups A and B were fed basal diets and Group C, D, and E received the same diets as groups A and B, but with supplements of 150 mg/kg, 300 mg/kg, and 600 mg/kg of BG515 orally for 12 weeks, respectively. Diabetes was induced in Groups B, C, D, and E by intravenous injection of 45 mg/kg of STZ per body weight in sodium citrate buffer (pH 4.5) via the tail vein. In the BG515 groups, we found increases in serum insulin levels, compared to the STZ-control group, but these data were not significant. In contrast, blood glucose and serum MDA concentrations decreased in the BG515 groups compare to the STZ-control group. At the 5th week, in all the BG515 administered groups, there were decreases in serum blood glucose levels compared to the STZ- control group, and this activity was very strong in the BG515-1 group at the 12th week. These results suggest that natural bio-complex compounds (BG515) may slightly suppress STZ-induced changes in serum MDA concentration via the maintenance of serum insulin levels, due to the prevention of $\beta-cell$ and glucagon destruction by STZ.

• 한국환경생태학회지
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• 제10권1호
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• pp.66-75
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• 1996

본 연구는 생물종자원 및 경관자원으로서의 보존가치가 큰 난온대 상록활엽수림의 식생구조를 정량적으로 파악하여 국토자원관리와 식재설계의 기초자료를 제공하는 것을 목적으로 하였다. 연구대상지는 전남 진도군 의신면의 선연기념물(107호)인 상록수림을 포함하는 첨찰산 일원이었다. 식생구조분석을 위하여 총 52개의 조사구(조사구면적 300m$^{2}$)를 설정하고 식생조사를 실시하였으며 TWINSPAN 및 DCA 기법을 적용하였다. 그 결과 7개의 식물군짐이 분리되었는데 이들 군집은 굴참나무-개서어나무군짐, 정가시나무군집, 구실잣밤나무-참가시나무군집, 구실잣밤나무-동백나무군집, 붉가시나무, 참식나무 등 상록활엽수로 천이되고 있는 천이 도중상의 식생구조이었다. 수종과 토양 및 입지환경과의 관계에서 참식나무, 종가시나무, 동백나무는 비옥한 토양에서 상대우점치가 컸고 소사나무는 고지대 능선부, 개서어나무는 저지대 곡간부나 산록부의 양호한 환경조건에서 분포하고 있는 것으로 나타났다. 앞으로 난온대림 지역의 관광지 주변이나 국,공유림의 삼림식생관리는 식생구조와 천이계열을 고려하여 상록활엽수림 복원을 촉진시키는 계획이 필요하며, 도시구역이나 공단조성시에는 황견 입지조건을 고려한 상록활엽수종의 식재가 바람직하다.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2016년도 춘계학술대회 및 임시총회
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• pp.25-25
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• 2016

Biological control has many advantages as a disease control method, particularly when compared with pesticides. One of the most important benefits is that biological control is an environmental friendly method and does not introduce pollutants into the environment. Another great advantage of this method is its selectivity. Selectivity is the important factor regarding the balance of agricultural ecosystems because a great damage to non target species can lead to the restriction of natural enemies' populations. The objective of this research was to evaluate the effects of several different bacterial isolates on the efficacy of biological control of soil borne diseases. White rot caused by Sclerotium cepivorum was reported to be severe disease of garlic and chive. The antifungal bacteria Burkholderia pyrrocinia CAB08106-4 was tested in field bioassays for its ability to suppress white rot disease. In field tests, B. pyrrocinia CAB08106-4 isolates suppressed white rot in garlic and chive, with the average control efficacies of 69.6% and 58.9%, respectively. In addition, when a culture filtrate of B. pyrrocinia CAB08106-4 was sprayed onto wounded garlic bulbs after inoculation with a Penicillium hirstum spore suspension in a cold storage room ($-2^{\circ}C$), blue mold disease on garlic bulbs was suppressed, with a control efficacy of 79.2%. These results suggested that B. pyrrocinia CAB08106-4 isolates could be used as effective biological control agents against both soil-borne and post-harvest diseases of Liliaceae. Chinese cabbage clubroot caused by Plasmodiophora brassicae was found to be highly virulent in Chinese cabbage, turnips, and cabbage. In this study, the endophytic bacterium Flavobacterium hercynium EPB-C313, which was isolated from Chinese cabbage tissues, was investigated for its antimicrobial activity by inactivating resting spores and its control effects on clubroot disease using bioassays. The bacterial cells, culture solutions, and culture filtrates of F. hercynium EPB-C313 inactivated the resting spores of P. brassicae, with the control efficacies of 90.4%, 36.8%, and 26.0%, respectively. Complex treatments greatly enhanced the control efficacy by 63.7% in a field of 50% diseased plants by incorporating pellets containing organic matter and F. hercynium EPB-C313 in soil, drenching seedlings with a culture solution of F. hercynium EPB-C313, and drenching soil for 10 days after planting. Soft rot caused by Pectobacterium carotovorum subsp. carotovorum was reported to be severe disease to Chinese cabbage in spring seasons. The antifungal bacterium, Bacillus sp. CAB12243-2 suppresses the soft rot disease on Chinese cabbage with 73.0% control efficacy in greenhouse assay. This isolate will increase the utilization of rhizobacteria species as biocontrol agents against soft rot disease of vegetable crops. Sclerotinia rot caused by Sclerotinia sclerotiorum has been reported on lettuce during winter. An antifungal isolate of Pseudomonas corrugata CAB07024-3 was tested in field bioassays for its ability to suppress scleritinia rot. This antagonistic microorganism showed four-year average effects of 63.1% of the control in the same field. Furthermore, P. corrugata CAB07024-3 has a wide antifungal spectrum against plant pathogens, including Sclerotinia sclerotiorum, Sclerotium cepivorum, Botrytis cinerea, Colletotrichum gloeosporioides, Phytophotra capsici, and Pythium myriotylum.

• Molecules and Cells
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• 제37권11호
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• pp.833-840
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• 2014

Cullin4-RING ubiquitin ligase (CRL4) is a family of multi-subunit E3 ligases. To investigate the possible involvement of CRL4 in heat stress response, we screened T-DNA insertion mutants of putative CRL4 substrate receptors that exhibited altered patterns in response to heat stress. One of the mutants exhibited heat stress tolerance and was named heat stress tolerant DWD1 (htd1). Introduction of HTD1 gene into htd1-1 led to recovery of heat sensitivity to the wild type level, confirming that the decrease of HTD1 transcripts resulted in heat tolerance. Therefore, HTD1 plays a negative role in thermotolerance in Arabidopsis. Additionally, HTD1 directly interacted with DDB1a in yeast two-hybrid assays and associated with DDB1b in vivo, supporting that it could be a part of a CRL4 complex. Various heat-inducible genes such as HSP14.7, HSP21, At2g03020 and WRKY28 were hyper-induced in htd1-1, indicating that HTD1 could function as a negative regulator for the expression of such genes and that these genes might contribute to thermotolerance of htd1-1, at least in part. HTD1 was associated with HSP90-1, a crucial regulator of thermotolerance, in vivo, even though the decrease of HTD1 did not affect the accumulation pattern of HSP90-1 in Arabidopsis. These findings indicate that a negative role of HTD1 in thermotolerance might be achieved through its association with HSP90-1, possibly by disturbing the action of HSP90-1, not by the degradation of HSP90-1. This study will serve as an important step toward understanding of the functional connection between CRL4-mediated processes and plant heat stress signaling.

• 한국약용작물학회지
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• 제17권6호
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• pp.439-444
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• 2009

This study was to set the guidelines of soil chemical components in order to assure the safety and quality of the panax ginseng from physiological disorder. The disorder symptoms appeared on the leaf with yellow spot, atrophy, yellow-brown spot, also showed red skin and rough skin of the root. Occurrence type of physiological disorder in cultivated field divided into two types : type I 'such as, yellow spot' consist of single disorder symptom; type II 'such as, yellow spot and yellow-brown spot' consist of two or more different disorder symptoms. The individual contribution of soil properties to the occurrence type was as follows ; The yellow spot was affected by Na > $NO_3$-N > salinity (EC) in soil. The same results was observed in red skin. Atrophy was affected by $NO_3$-N > salinity (EC) > Ca > Mg. Rough skin was affected by $P_2O_5$>pH>Organic material > K. It showed positive associated to $P_2O_5$, pH and K, but negative associated to organic matter. Simultaneous occurrence of two different disorder, including cases which yellow spot and yellow-brown spot, those were affected by $NO_3$-N > salinity (EC) > Na > Mg. In the case of atrophy plus yellow-brown spot, those also were affected by in the order : $NO_3$-N > salinity (EC) > Ca > Mg > Na. Red-rough skin was affected in the order : salinity (EC) > $NO_3$-N > K > Na. Soil chemical components appear to be related to occurrence of physiological disorder, particularly in salinity (EC) and $NO_3$-N. The salinity (EC) and $NO_3$-N were negative related to plant growth. In addition, exchangeable cation capacity play critical roles in attributing to complex occurrence of physiological disorder.

• 한국전통조경학회지
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• 제36권1호
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• pp.45-54
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• 2018

본 연구는 서울시의 국가지정문화재이자 도심 속 전통문화공간인 4대궁(경복궁, 창덕궁, 창경궁, 덕수궁)과 종묘를 중심으로 식물상을 조사하고 귀화식물을 확인하였으며 그 결과는 다음과 같다. 전체분류군은 82과 201속 285종 1아종 29변종으로 총 315분류군이 확인되었으며, 귀화식물은 덕수궁이 33분류군, 종묘가 14분류군, 경복궁이 21분류군, 창덕궁이 11분류군, 창경궁이 11분류군으로 나타났다. 원산지 분석결과 북아메리카(nA)와 유럽(Eu) 그리고 유라시아(Eu-As)가 높은 분포율을 보였으며, 생활형 분석결과 목본류보다 초본류의 비율이 높은 것으로 확인되었다. 그리고 경복궁을 제외한 나머지 대상지는 다년생 비율보다 일년생 비율이 높은 것으로 나타났다. 귀화도 분석결과 귀화도 3과 귀화도 5에 해당되는 귀화식물의 비율이 높았으며, 유입시기를 살펴보면 초기 정착종보다 최근 유입된 귀화식물이 더 많은 것으로 나타났다. 대상지간의 유사도는 40% 이상 유사한 것으로 확인되었으며, 5개 대상지에 공통적으로 나타나는 귀화식물의 종다양성은 매우 낮은 것으로 나타났다. 이를 통해 관리에 대한 개선방안을 제시함에 따라 문화유산 식재경관 조성 및 귀화식물 관리에 기초자료로서 그 목적이 있다.