• Journal of Ecology and Environment
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• 제36권1호
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• pp.39-47
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• 2013

The expression of transgenic traits in genetically modified crops is sometimes associated with decreases in crop performance or fitness. These decreases in performance or fitness of transgenic plants in unfavourable conditions may provide valuable information about the ecological consequences of transgene escape. In a glasshouse trial, we tested the cost associated with resistance to herbicides by comparing the growth, yield, and competitive ability of transgenic rice with its parental non-transgenic line. This new line was developed for constitutive overexpression of protoporphyrinogen oxidase (PPO) to increase resistance to herbicides. We evaluated nine agronomic traits of transgenic and non-transgenic rice grown in a replacement series design over four densities. Competitive ability was also assessed between transgenic and non-transgenic plants by analyzing their relative yields based on biomass and seed weight data. Our results indicated that non-transgenic plants showed greater performance than did the transgenic plants when those genotypes were grown in mixtures. The non-transgenic rice plants exhibited superior competitive ability at certain combinations of planting densities and genotype proportions. These results suggest that PPO-herbicide resistance incurs some costs in plant performance and competitive ability.

• Journal of Microbiology and Biotechnology
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• 제30권11호
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• pp.1680-1687
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• 2020

Fungal endophytes are symbiotic microorganisms that are often found in asymptomatic plants. This study describes the genetic diversity of the fungal endophytes isolated from the roots of plants sampled from the west coast of Korea. Five halophytic plant species, Limonium tetragonum, Suaeda australis, Suaeda maritima, Suaeda glauca Bunge, and Phragmites australis, were collected from a salt marsh in Gochang and used to isolate and identify culturable, root-associated endophytic fungi. The fungal internal transcribed spacer (ITS) region ITS1-5.8S-ITS2 was used as the DNA barcode for the classification of these specimens. In total, 156 isolates of the fungal strains were identified and categorized into 23 genera and two phyla (Ascomycota and Basidiomycota), with Dothideomycetes and Sordariomycetes as the predominant classes. The genus Alternaria accounted for the largest number of strains, followed by Cladosporium and Fusarium. The highest diversity index was obtained from the endophytic fungal group associated with the plant P. australis. Waito-C rice seedlings were treated with the fungal culture filtrates to analyze their plant growth-promoting capacity. A bioassay of the Sm-3-7-5 fungal strain isolated from S. maritima confirmed that it had the highest plant growth-promoting capacity. Molecular identification of the Sm-3-7-5 strain revealed that it belongs to Alternaria alternata and is a producer of gibberellins. These findings provided a fundamental basis for understanding the symbiotic interactions between plants and fungi.

• 생명과학회지
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• 제18권4호
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• pp.488-493
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• 2008

Phosphate, a favorable phosphorous form for plant, is one of major nutrient elements for growth and development in plants. Plants exhibit various physiological and biochemical responses in reaction to phosphate starvation in order to maintain phosphate homeostasis. Of them, expression of high affinity phosphate transporter gene family and efficient uptake of phosphate via them is a major physiological process for adaption to phosphate deficient environment. Although the various genetic resources of high affinity phosphate transporter are identified recently, little is known about their functions in plant that is prerequisite information before applying to crop plants to generate valuable transgenic plants. We demonstrated that Arabidopsis transgenic plants over-expressing two different high affinity phosphate transporter gens, OsPT1 and OsPT7, derived from rice, exhibit better growth responses compared with wild-type under phosphate starvation condition. Specially, OsPT7 gene has proven to be more effective to generate Arabidopsis transgenic plant tolerant to phosphate deficiency than OsPT1. Furthermore, the expression level of AtPT1 gene that is one of reporter genes specifically induced by phosphate starvation was significantly low compared with wild-type during phosphate starvation. Taken together, these results collectively suggest that over expression of OsPTl and OsPT7 genes derived from monocotyledonous plant function efficiently in the dicotyledonous plant, relieving stress response caused by phosphate starvation and leading to better growth rate.

• 한국산림과학회지
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• 제57권1호
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• pp.8-13
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• 1982

본(本) 조사(調査)는 1981년(年) 7월(月) 18일(日)에서 8월(月) 11일(日) 사이에 4개(個) 공단(工團)(포항(浦項), 울산(蔚山), 온산(温山) 및 여천(麗川))을 대상(對象)으로 오염발생원(汚染發生源)으로부터 2km이내(以內)의 식물(植物)의 종류(種類)와 내연성(耐煙性) 식물(植物)의 발굴(發掘) 및 대기오염(大氣汚染)이 식물생육(植物生育)에 미치고 있는 범위(範圍)를 지표식물(指標植物)에 의(依)한 육면적(肉眠的) 방법(方法)으로 조사(調査)하였으며 얻어진 결과(結果)는 다음과 같다. 1) 4개(個) 공단(工團)에 나타난 식물(植物)의 종류(種類)는 91과(科) 6아과(亞科) 213속(屬) 290종(種)이었고 과(科) 순위별(順位別)로 보면 포항공단내(浦項工團內)에는 54과(科) 102속(屬) 126종(種)으로 콩(科) 16종(種), 벼(科) 11종(種), 장미과(科) 9종(種) 및 국화과(科) 9종(種)의 순(順)이었고, 울산공단내(蔚山工團內)에는 61과(科) 131속(屬) 158종(種)으로 국화과(科) 17종(種), 벼과(科) 16종(種), 콩과(科) 15종(種), 장미과(科) 9종(種), 마디풀과(科) 7종(種) 및 가지과(科) 6종(種)의 순(順)이었고, 온산공단내(温山工團內)에는 46과(科) 98속(屬) 113종(種)으로 국화과(科) 12종(種), 벼과(科) 12종(種), 콩과(科) 12종(種), 장미과(科) 6종(種) 및 마디풀과(科) 6종(種)의 순(順)이었고, 여천공단내(麗川工團內)에는 71과(科) 150속(屬) 188종(種)으로 장미과(科) 15종(種), 콩과(科) 15종(種), 국화과(科) 15종(種), 벼과(科) 14종(種), 마디풀과(科) 7종(種) 및 버드나무과(科) 6종(種)의 순(順)이었다. 2) 4개(個) 공단지역(工團地域)에서 조사(調査)된 내연성(耐煙性) 식물(植物)은 표(表) 1과 같다. 3) 공단지역(工團地域)에 식재(植栽)될 추자수종(推蔗樹種)은 콩과(科)에 족제비싸리, 조록싸리, 싸리, 아까시나무 및 회화나무, 참나무과(科)에 상수리나무, 졸참나무 및 굴참나무, 버드나무과(科)에 은사시나무, 능수버들, 물푸레나무과(科)에 쥐똥나무, 광나무, 자작나무과(科)에 산오리나무, 노박덩굴과(科)에 사철나무, 인동과(科)에 아왜나무 및 소나무과(科)에 히말라야시이 다이다.

• Journal of Plant Biotechnology
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• 제32권3호
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• pp.151-159
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• 2005

Injury caused by reactive oxygen species (ROS), known as oxidative stress, is one of the major damaging factors in plants exposed to environmental stress. Chloroplasts are specially sensitive to damage by ROS because electrons that escape from the photosynthetic electron transfer system are able to react with relatively high concentration of $O_2$ in chloroplasts. To cope with oxidative stress, plants have evolved an efficient ROS-scavenging enzymes such as superoxide dismutase (SOD) and ascorbate peroxidase (APX), and low molecular weight antioxidants including ascorbate, glutathione and phenolic compounds. To maintain the productivity of plants under the stress condition, it is possible to fortify the antioxidative mechanisms in the chloroplasts by manipulating the antioxidation genes. A powerful gene expression system with an appropriate promoter is key requisite for excellent stress-tolerant plants. We developed a strong oxidative stress-inducible peroxidase (SWPA2) promoter from cultured cells of sweetpotato (Ipomoea batatas) as an industrial platform technology to develop transgenic plants with enhanced tolerance to environmental stress. Recently, in order to develop transgenic sweetpotato (tv. Yulmi) and potato (Solanum tuberosum L. cv. Atlantic and Superior) plants with enhanced tolerance to multiple stress, the genes of both CuZnSOD and APX were expressed in chloroplasts under the control of an SWPA2 promoter (referred to SSA plants). As expected, SSA sweetpotato and potato plants showed enhanced tolerance to methyl viologen-mediated oxidative stress. In addition, SSA plants showed enhanced tolerance to multiple stresses such as temperature stress, drought and sulphur dioxide. Our results strongly suggested that the rational manipulation of antioxidative mechanism in chloroplasts will be applicable to the development of all plant species with enhanced tolerance to multiple environmental stresses to contribute in solving the global food and environmental problems in the 21st century.

• Journal of Ecology and Environment
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• 제45권4호
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• pp.277-286
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• 2021

Background: As trade increases, the influx of various alien species and their spread to new regions are prevalent and no longer a special problem. Anthropogenic activities and climate changes have made the distribution of alien species out of their native range common. As a result, alien species can be easily found anywhere, and they have nothing but only a few differences in intensity. The prevalent distribution of alien species adversely affects the ecosystem, and a strategic management plan must be established to control them effectively. To this end, hot spots and cold spots were analyzed according to the degree of distribution of invasive alien plants, and major environmental factors related to hot spots were found. We analyzed the 10,287 distribution points of 126 species of alien plants collected through the national survey of alien species by the hierarchical model of species communities (HMSC) framework. Results: The explanatory and fourfold cross-validation predictive power of the model were 0.91 and 0.75 as AUC values, respectively. The hot spots of invasive plants were found in the Seoul metropolitan area, Daegu metropolitan city, Chungcheongbuk-do Province, southwest shore, and Jeju island. Generally, the hot spots were found where the higher maximum temperature of summer, precipitation of winter, and road density are observed, but temperature seasonality, annual temperature range, precipitation of the summer, and distance to river and sea were negatively related to the hot spots. According to the model, the functional traits accounted for 55% of the variance explained by the environmental factors. The species with higher specific leaf areas were more found where temperature seasonality was low. Taller species preferred the bigger annual temperature range. The heavier seed mass was only preferred when the max temperature of summer exceeded 29 ℃. Conclusions: In this study, hot spots were places where 2.1 times more alien plants were distributed on average than non-hot spots (33.5 vs 15.7 species). The hot spots of invasive plants were expected to appear in less stressful climate conditions, such as low fluctuation of temperature and precipitation. Also, the disturbance by anthropogenic factors or water flow had positive influences on the hot spots. These results were consistent with the previous reports about the ruderal or competitive strategies of invasive plants instead of the stress-tolerant strategy. The functional traits are closely related to the ecological strategies of plants by shaping the response of species to various environmental filters, and our result confirmed this. Therefore, in order to effectively control alien plants, it is judged that the occurrence of disturbed sites in which alien plants can grow in large quantities is minimized, and the river management of waterfronts is required.

• Journal of Plant Biotechnology
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• 제38권1호
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• pp.1-8
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• 2011

최근 시설재배의 증가나 새만금 간척지의 개발 등 염류 농도가 높은 토양에서의 작물 재배에 대한 수요가 점차적으로 증가하고 있는 상황에서 고염환경 하에서 세포내로 주입된 염 분자를 제한된 구역으로 격리하여 염류내성을 주도록 하는 anti-porter 유전자 TANHX, HVNHX를 우리나라 주요 화훼작물이며 수출유망 작물인 국화로 도입하는 분자육종이 백마 등 5품종에 대하여 이루어졌다. 선발 마커를 이용한 배지선발 과정을 통하여 선발된 기내 식물체 390개체를 대상으로 토양 순화를 거쳐 284계통의 국화 형질전환체가 획득되었으며, 얻어진 식물체 중 임의로 40계통을 선발하고 PCR을 거쳐 진성 여부를 확인한 결과 30계통에서 target band가 검출되어 75%의 배지 발 성공률을 나타내었다. PCR 분석 선발 계통을 포함하여 토양 순화된 284계통을 대상으로 직접적으로 NaCl 0.2 ~ 1.2% (300 mM) 범위로 내염성 생물검정을 실시한 결과 NaCl 0.8% (200 mM) 농도에서도 생존 및 생장이 가능한 15계통이 선발되었으며 이중 7계통은 NaCl 1.2%(300 mM) 내에서도 생존이 가능하였다. 내염성 특성형질 도입을 위하여 anti-porter 유전자 HVNHX가 도입되어 선발된 형질전환 계통의 스트레스 저항성 정도 및 세포 형태적 특성변화가 관찰되었다. 선발된 계통은 NaCl 1.2% (300 mM) 처리 생존가능 7계통을 포함하여 NaCl 0.8% (200 mM) 관수 처리 하에서 생존 및 생장이 가능한 15계통이었다. 세포형태 특성은 전자현미경 (SEM)을 이용하여 형질전환체 및 비 형질전환체의 공변세포를 염 처리 후 관찰함으로서 이루어졌는데 형질전환체, 비형질전환체 모두 무처리에 비해 NaCl 처리한 식물체의 공변세포의 두께가 두꺼워지고 조직 치밀도가 증가하였으며 형질전환체의 경우 비 형질전환체에 비해 두꺼워지는 정도나 조직의 치밀도 증가 정도가 높아 염에 대한 내성이 강화되었음을 알 수 있었고 염 처리 후 세포의 생존정도 비교를 통한 내염 스트레스에 대한 저항성 정도를 측정하고자 TTC 검정을 실시한 결과 강 내염성 계통의 TTC 수치가 높게 나왔으며 NaCl 처리 농도가 높아질수록 TTC 수치가 낮아지는 경향이었으나 강 내염성 7계통은 1.2% NaCl 처리에서도 0.206 ~ 0.331로 비형질전환체의 0.046 중내염성 계통의 0.114 ~ 0.193에 비해 높은 세포생존 비율을 나타내었다. 또한 식물이 스트레스에 대항하기 위하여 분비하는 아미노산인 Proline의 함량을 계통별로 측정한 결과 강 내염성 형질전환 계통이 높게 나왔으며 NaCl 처리 농도가 높아질수록 증가하는 경향을 나타내어 강 내염성 7계통은 1.2% NaCl 처리에서 2.255 ~ 2.638 mg/kg로 중 내염성 형질전환 계통의 1.496 ~ 2.125에 비해 높게 형성되었다.

• 식물병연구
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• 제17권3호
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• pp.326-333
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• 2011

Ralstonia solanacearum에 의해 발생하는 토마토 풋마름병에 대하여 저항성으로 알려진 토마토 순계 품종의 국내 병원균에 대한 저항성 반응을 온도별로 평가하였다. 한국에서 분리된 R. solanacearum 균주로 토마토 순계 6 품종의 저항성을 평가한 결과 기존에 저항성으로 알려진 토마토 순계들이 한국 분리균주에 대하여는 대부분 저항성을 유지하지 못하였다. 병원성이 강한 균주인 SL341 (race 1, biovar 4) 균주는 검정한 대부분의 품종에서 온도에 관계없이 강한 병원성을 보였다. 반면, 담배에서 분리된 균주인 SL1944(race 1, biovar 4)은 온도에 따라 발병진전이 현저하게 차이가 났다. Moneymaker와 Bonny Best와 같은 품종은 온도에 관계없이 SL1944에 대하여 감수성이었다. 그러나, 풋마름병 저항성 품종으로 알려진 Hawaii 7998, Hawaii 7996, B-blocking 품종은 오히려 상대적으로 고온인 조건($35^{\circ}C$에서 14시간 명조건과 $28^{\circ}C$에서 10시간 암조건)에서 급격히 발병하였다. 병 진전은 동일한 품종의 낮은 온도에서 병 진전이나 Moneymaker나 Bonny Best 같은 품종에서 동일한 고온 조건의 발병에 비해 눈에 띄게 빨랐다. 본 연구결과는 국내에서 분리된 균주들이 기존에 저항성 토마토 품종을 가해할 수 있으며 고온조건에서는 품종의 저항성 붕괴의 가능성으로 급격한 풋마름병이 유발될 수 있음을 제시한다.

• 한국작물학회지
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• 제37권3호
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• pp.288-298
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• 1992

Since the major important factors limiting plant growth and crop productivity are environmental stresses, of which low temperature is the most serious. It has been well known that many physiological processes are alterant in response to the environmental stress. With regard to the relationship between plant hormones and the regulation of chilling tolerance in rice seedlings, the major physiological roles of plant hormones: abscisic acid, ethylene and polyamines are evaluated and discussed in this paper. Rice seedlings were grown in culture solution to examine the effect of such plant hormones on physiological characters related to chilling tolerance and also to compare the different responses among tested cultivars. Intact seedlings about 14 day-old were chilled at conditions of 5$^{\circ}C$ and 80% relative humidity for various period. Cis-(＋)-ABA content was measured by the indirect ELISA technique. Polyamine content and ethylene production in leaves were determined by means of HPLC and GC respectively. Chilling damage of seedlings was evaluated by electrolyte leakage, TTC viability assay or servival test. Our experiment results described here demonstrated the physiological functions of ABA, ethylene, and polyamines related to the regulation of chilling tolerance in rice seedlings. Levels of cis-(＋)-ABA in leaves or xylem sap of rice seedlings increased rapidly in response to 5$^{\circ}C$ treatment. The tolerant cultivars had significant higher level of endogenous ABA than the sensitive ones. The ($\pm$)-ABA pretreatment for 48 h increased the chilling tolerance of the sensitive indica cultivar. One possible function of abscisic acid is the adjustment of plants to avoid chilling-induced water stress. Accumulation of proline and other compatible solutes is assumed to be another factor in the prevention of chilling injuies by abscisic acid. In addition, the expression of ABA-responsive gene is reported in some plants and may be involving in the acclimation to low temperature. Ethylene and its immediate precusor, 1-amincyclopropane-1-carboxylic acid(ACC) increased significantly after 5$^{\circ}C$ treatment. The activity of ACC synthase which converts S-adenosylmethionine (SAM) to ACC enhanced earlier than the increase of ethylene and ACC. Low temperature increased ACC synthase activity, whereas prolonged chilling treatment damaged the conversion of ACC to ethylene. It was shown that application of Ethphon was beneficial to recovering from chilling injury in rice seedlings. However, the physiological functions of chilling-induced ethylene are still unclear. Polyamines are thought to be a potential plant hormone and may be involving in the regulation of chilling response. Results indicated that chilling treatment induced a remarkable increase of polyamines, especially putrescine content in rice seedlings. The relative higher putrescine content was found in chilling-tolerant cultivar and the maximal level of enhanced putrescine in shoot of chilling cultivar(TNG. 67) was about 8 folds of controls at two days after chilling. The accumulation of polyamines may protect membrane structure or buffer ionic imbalance from chilling damage. Stress physiology is a rapidly expanding field. Plant growth regulators that improve tolerance to low temperature may affect stress protein production. The molecular or gene approaches will help us to elucidate the functions of plant hormones related to the regulation of chilling tolerance in plants in the near future.

• Journal of Plant Biotechnology
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• 제38권2호
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• pp.105-116
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• 2011

Transgenic zoysiagrass (Zoysia japonica Steud.) expressing the bar gene inserted in the plant genome has been generated previously through Agrobacterium tumefaciens-mediated transformation. The GM zoysiagrass (event: JG21) permits efficient management of weed control of widely cultivated zoysiagrass fields, reducing the frequency and cost of using various herbicides for weed control. Now we have carried out the environmental risk assessment of JG21 prior to applying to the governmental regulatory agency for the commercial release of the GM turf grass outside of test plots. The morphological phenotypes, molecular analysis, weediness and gene flow from each test plot of JG21 and wild-type zoysiagrasses have been evaluated by selectively analyzing environmental effects. There were no marked differences in morphological phenotypes between JG21 and wild-type grasses. The JG21 retained its stable integration in the host plant in T1 generation, exhibiting a 3:1 segregation ratio according to the Mendelian genetics. We confirmed the copy number (1) of JG21 by using Southern blot analysis, as the transgenic plants were tolerant to ammonium glufosinate throughout the culture period. From cross-fertilization and gene flow studies, we found a 9% cross-pollination rate at the center of JG21 field and 0% at distances over 3 m from the field. The JG21 and wild-type zoysiagrass plants are not considered "weed" because zoysiagrasses generally are not dominant and do not spread into weedy areas easily. We assessed the horizontal gene transfer (HGT) of the transgene DNA to soil microorganisms from JG21 and wild-type plants. The bar gene was not detected from the total genomic DNA extracted from each rhizosphere soil of GM and non-GM Zoysia grass fields. Through the monitoring of JG21 transgene's unintentional release into the environment, we found no evidence for either pollen mediated gene flow of zoysiagrass or seed dispersal from the test field within a 3 km radius of the natural habitat.