점박이응애(Tetranychus urticae)는 250과 1400여종의 식물에 피해를 주고 있는 해충으로 높은 번식력, 근친 교배, 무성생식, 짧은 수명주기 로 년간 발생회수가 많기 때문에 약제에 대한 저항성이 빠르게 발달하는 종이다. 저항성 기작은 AChE 저해, sodium channel modulator, glutamate gated chloride channels allosteric, mite growth inhibitors, inhibitors of acetyl CoA carboxylase, mitochondrial ATP synthase 저 해, mitochondrial complex I, II, III, 그리고 electron transport 저해 등이 있으며 약제에 따라 작용기작이 다르므로 약제살포 시 확인이 필요하 다. 약제저항성 발달을 평가하는 독성시험방법으로 slide dip, leaf dip, leaf disc, topical application, vial leaf dip, spray potter tower, leaf vial dipping 등이 있으며 최근에는 분자학적 진단법 등도 개발되어 있으나 이들 방법은 해충 종이나 발육상태에 약제에 따라 정확도가 달라지므로 현장 에 가장 맞는 방법을 찾아야 할 것이다. 저항성 점박이응애를 효과적으로 관리하기 위한 방법으로 저항성 위험이 낮은 살응애제(chemical acaricide) 약제 선발, 천적인 칠레이리응애, 사막이리응애를 이용한 생물적 방제, 님, 제충국, 등 식물추출물이나 정유를 활용한 친환경적인 방법 등이 제시되 고 있으며 종합관리를 위한 다양한 요인을 찾아 약제 사용을 줄여 나가야 할 것이다.
토마토반점위조바이러스 (TSWV)는 고추, 토마토 등 경제적으로 중요한 작물에 심각한 피해를 주는 바이러스들 중 한 종이다. TSWV의 넓은 기주범위, 매개충인 총채벌레 방제의 어려움 및 TSWV의 효과적인 치료제가 없기 때문에, 저항성 품종을 사용하는 것이 TSWV를 예방하는 가장 효과적인 수단이 될 수 있다. 본 연구에서는 토마토에서 분리된 TSWV 분리주 (SW-TO2)의 유전학적·생물학적 특성을 구명하고, 최근에 국내에서 분리된 구기자, 머위, 당귀 TSWV 분리주와 비교하였다. 순수분리된 SW-TO2는 28 종의 지표식물 중 토마토를 포함한 17종에서 원형반점, 모자이크 증상 등 전신감염 증상을 보였다. SW-TO2의 유전자 계통분석 결과 국내에서 분리된 고추, 구기자 TSWV 분 리주와 98~99%의 상동성을 보이며 같은 그룹에 속하였다. TSWV 저항성 평가를 위한 생물검정법을 확립하고, 시판되고 있는 고추와 토마토 품종을 대상으로 4종의 TSWV 분리주에 대한 저항성 평가를 검정하였다. TSWV 저항성 평가는 첫째, 접종엽에 괴사반점 증상이 나타나거나 병징이 없는 경우, 둘째, 상엽에 병징이 없는 경우, 셋째, 상엽을 RT-PCR 진단한 결과 음성이 나왔을 경우 등 3가지 조건이 다 충족될 때 저항성으로 평가하였다.
For our survey of insecticidal resistance of Palm thrips (Thrips palmi Karny), we established the discriminating time (DT) and concentration (DC) of nine insecticides, and we conducted a bioassay about seven local populations via leaf-dipping methods. The discriminating times of the recommended concentration (RC) were 24 h at emamectin benzoate EC and spinetoram SC, 48 h at chlorfenapyr EC, 72 h at spinosad SC, cyantraniliprole EC, acetamiprid WP, dinotefuran WG, imidacloprid WP and thiacloprid SC after treatment. The DC estimated the concentration which showed the difference within the mortalities of these local populations. The DCs were emamectin benzoate EC 0.013 mg L-1 (RC, 10.8 mg L-1), spinetoram SC 0.125 mg L-1 (RC, 25.0 mg L-1), chlorfenapyr EC 0.25 mg L-1 (RC, 50.0 mg L-1), spinosad SC 0.083 mg L-1 (RC, 50.0 mg L-1) and cyantraniliprole EC 5.0 mg L-1 (RC, 50.0 mg L-1), and DCs of neonicotinoids were their RCs, that is, acetamiprid WP (RC, 40.0 mg L-1), dinotefuran WG (RC, 20.0 mg L-1), imidacloprid WP (RC, 50.0 mg L-1) and thiacloprid SC (RC, 50.0 mg L-1). From our investigation into the resistance of the local populations with DT and DC application, the neonicotinoid insecticides have shown a high resistant level for all the local populations, and the other insecticides have demonstrated low or non-resistance. In the use of neonicotinoid insecticides to control Palm thrips, one must take caution. As a result, the establishment of DT and DC in the single dose bioassay method was helpful for surveying the insecticide response dynamics and the development of an insecticide resistance management strategy.
There are studies on the assessment of non-edible transgenic plants on soil microbial communities. In this research we evaluated the effect of virus-resistant trigonal cactus on soil microbial communities of the rhizosphere. Soil samples are collected and compared in genetically modified (GM) and non-GM trigonal cactus cultivation fields during vegetative growth period and post-harvest period. Biolog EcoplateTM was used to evaluate the functional diversity of soil microbial communities. There were no significant differences between the GM and non-GM soil samples collected during the vegetative growth period. However, we observed temporary difference in carbon substrate utilization. Principal component analysis showed that soil microbiota was influenced not by presence of GM or non-GM trigonal cacti, but rather by the cultivation period. Denaturing gradient gel electrophoresis fingerprinting revealed that virus-resistant trigonal cactus cultivation had insignificant effect on soil microbial communities including dominant rhizosphere bacteria, actinomycetes, and fungi. We found no clear evidence of GM trigonal cactus cultivation affecting the functional diversity of soil microbial communities.
Chlorantraniliprole은 diamide계통의 나비목 유충 방제제로서 기존 살충제들과는 다르게 Ryanodine Receptor (RyR)에 작용하여 Ca2+ 분비에 이상을 유도하여 치사시킨다. 하지만 반복 사용으로 일부 나비목 해충에서 RyR 유전자의 돌연변이에 의한 저항성 계통이 보고되었다. 본 연구에서는 Chlorantraniliprole 저항성 발달 기작을 초파리를 모델 곤충으로 선정하여 수행하였다. EMS 처리로 비특이적 돌연변이를 유도시킨 후, Chlorantraniliprole을 낮은 농도 (5ppm)와 높은 농도 (30ppm)에서 도태를 시작하여 2종류의 저/고도태압 저항성 계통을 확보하였다. 섭식독성 수준을 비교한 결과, 고도태압군의 저항성 수준이 대조군에 비해 약 8배 정도 높게 나타났다. 또한 RyR의 발현량과 생화학적 해독 기전의 차이를 구명한 결과, 2개의 저항성 군집은 대조군보다 전반적으로 높은 생화학적인 해독 기전의 활성화를 보여주었다. 향후 연구는 저항성 기전을 밝혀냄으로써 저항성 회피기작을 알아내는데 도움을 줄 것이다. (본 연구는 농촌진흥청 연구과제 (PJ010821032016)의 지원을 받았음)
There has been an accelerating increase in water reuse due to growing world population, rapid urbanization, and increasing scarcity of water resources. However, it is well recognized that water reuse practice is associated with many human health and ecological risks due to numerous chemicals and pathogenic microorganisms. Especially, the potential transmission of infectious disease by hundreds of pathogenic viruses in wastewater is one of the most serious human health risks associated with water reuse. In this study, we determined the response of different bacteriophages representing various bacteriophage groups to chlorination in real wastewater in order to identify a more reliable bacteriophage indicator system for chlorination in wastewater. Different bacteriophages were spiked into secondary effluents from wastewater plants from three different geographic areas, and then subjected to various doses of free chlorine and contact time at 5˚C in a bench-scale batch disinfection system. The inactivation of φX174 was relatively rapid and reached ∼4 log10 with a CT value of 5 mg/L*min. On the other hand, the inactivation of bacteriophage PRD1 and MS2 were much slower than the one for φX174 and only ~1 log10 inactivation was achieved by a CT value of 10 mg/L*min. Overall, the results of this study suggest that bacteriophage both MS2 and PRD1 could be a reliable indicator for human pathogenic viruses for chlorination in wastewater treatment processes and water reuse practice.
최근 지역적으로 나타나고 있는 침입종인 꽃노랑총채벌래[Frakliniella occidentalis (Pergande) (Thysanoptera: Thripidae)]의 밀도 감소 현상이 토착종이면서 동소종(sympatric species)인 대만총채벌레[F. intonsa (Trybom)]에 의한 생물적 저항성과 환경 요인에 의한 비생물적 저항성이 나타난 결과라는 가설을 세우고 이를 검증하였다. 대만총채벌레는 꽃노랑총채벌레에 비해 발육률이 빠르며 성충 수명, 생식률(R0), 내적 자연 증가율(rm) 모두 높았다. 또한 경쟁 상태에서도 대만총채벌레는 꽃노랑총채벌레에 비해 수명과 생식에서 영향을 상대적으로 덜 받았으며, 특히 두 종간의 행동 관찰 실험에서는 대만총채벌레 의 섭식시간뿐만 아니라 먹이자원을 경계하는 시간이 각각 1.3과 42.8배 더 길어 두 종간 간섭경쟁이 있었다. 온도와 습도를 달리한 환경 조합에서 대만총채벌레가 꽃노랑총채벌레에 비해 고습 조건에서 생존율이 더 높았다. 다만, 대만총채벌레 는 꽃노랑총채벌레에 비해 살충제에 대한 감수성이 높았다. 이상의 결과로 최근 꽃노랑총채벌레의 지역적 밀도 감소 효과는 경쟁종인 대만총채벌레에 비해 낮은 내적 자연 증가율과 간섭경쟁에 의해 나타난 현상으로 판단된다. 다만, 더 넓은 지역에 대한 조사와 먹이 식물과 천적에 의한 영향 등에 대한 추가 연구가 필요하다.
Resistance evolution to organophosphate-based pesticides in apple and pear inhabiting arthropods of western North America extends to many classes of pest and some beneficial species. Resistance management programs to minimize resistance in pests while exploiting it in natural enemies have met with mixed success. Among beneficials, resistances have been exploited mostly among predators of pest mites. Evolution of resistant mites, leafminers, leafhopper, aphids, leafrollers and some internal fruit feeders have led to development of new monitoring methods and means to delay or avoid resistance. But it is resistance to azinphosmethyl in codling moth (Cydia pomonella) that is changing the pest control system and moving it from chemical to biologically-based means. Newly merging IPM system will depend more on use of biological, cultural, behavior and genetic controls. But more selective pesticides also will be needed to augment pheromones, resistant host plants and genetically altered organisms. These more biologically-based tactics will be prone to resistance evolution in pests as well, if used too unilaterally and/or too extensively.
The detection of the genome-based antibiotic resistance gene is an essential analysis process for the purpose of verifying the safety of probiotic strains, including lactic acid bacteria. In this study, 4 analysis platforms (AMRFinderPlus, staramr, rgi, ABRicate) were used for cross-comparison of 782 genomes corresponding to 19 kinds of probiotic species notified as functional foods. As a result of the analysis, the relatively fewest number of antibiotic resistance genes were detected in strains belonging to the order Lactobacillales, and antibiotic resistance genes were detected in 322 genomes used in the case of 2 types of Enterococcus genus. In addition, the presence and type of antibiotic resistance gene detection showed a lot of difference even for the same genome sequence depending on the database and analysis algorithm used by the analysis platform. These results can be confused in evaluating the potential for transmission of antibiotic resistance genes inherent in specific lactic acid bacteria and predicting potential risks that may occur in the future. Accordingly, it is judged that the antibiotic resistance gene-related analysis criteria need to be established more clearly and specifically in the safety evaluation of probiotic bacteria.
Background : In the process of developing new disease-resistant cultivar of Rehmannia glutinosa, it is essential to screen plants based on resistance to their disease. But until now, we have relied on visual inspection for selection of disease-resistant cultivar. Therefore, this experiment was carried out to establish an efficient and reliable screening system and test the resistance to leaf spot disease in R. glutinosa cultivars developed until now.
Methods and Results : We have tested 11 R. glutinosa cultivars developed so far. Rootstock of R. glutinosa were sown in 20 × 20 ㎝ plastic square port and grown in green house at 25 ± 5℃ for four months and then cutting leaves were inoculated with Phoma sp. HCRD 17103 by spraying spore suspention of fungus at concentration of 1 × 107 spore/㎖. The inoculated leaves were incubated in a dew chamber at 25℃ for 48h and then transferred to glass house (25 ± 5℃, RH 80% ≥ ). After 3 - 5 days when the most susceptible cultivar had lesion area over 40%, disease severity of the cultivars was investigated on a scale of 0 - 9 (0 = healthy, 1 = 0 - 1%, 3 = 1.1 - 10%, 5 = 10.1 - 20%, 7 = 20.1 - 40%, 9 = 40.1% over). The degree of resistance was determined according to the disease index (0 and 1 = resistant, 3 = moderately resistant, 5, 7 and 9 = susceptible). As a result of experiments according to the above criteria, the disease index of cultivar Gogang, Dagang, Segang, Yeongang, Wongang, and Dahwang was 1, cultivar Togang, Daegyung, Jiwhang 1 and Goryeo was 3, cultivar Hwanggang was 9, respectively.
Conclusion : From the above results, six cultivars such as Gogang, Dagang, Segang, Yeongang, Wongang, and Dahwang were resistant, four cultivar such as Togang, Daegyung, Jiwhang 1 and Goryeo were moderately resistant, and only one cultivar Hwanggang was susceptible to the leaf spot disease by Phoma sp. This experiment used only leaves and we plan to use whole plants in the future to see more accurate resistance response.
In this study, we compared disease incidence rate and phyllosphere microbial community between drought resistance transgenic rice (Agb0103) and non-transgenic Ilmi (NGM) during 2011-2014 to examine an environmental risk assessment of drought resistance transgenic rice (Agb0103). As the results, major diseases such as sheath blight, brown spot, leaf blast and false smut were occurred, however, there were no significant disease incidence rate between Agb0103 and NGM. As the results of counting bacterial and fungal viable cell, the colonies were increased or decreased which affected by environmental conditions, however there were no differences between Agb0103 and NGM. Also unweighted pair-group method with arithmetic averaging (UPGMA) analysis based on polymerase chain reaction with denaturing gel electrophoresis (PCR-DGGE) revealed that DGGE band pattern of bacterial and fungal communities were clustered by each month and there were no differences between Agb0103 and NGM. Furthermore, isolated casual agents causing sheath blight and brown spot were collected from Agb0103 and NGM, and they revealed that each of pathogens were no differences in morphology and pathogenicity. Therefore, our results suggested that Agb0103 showed no differences in disease incidence rate, characteristic of pathogens and phyllosphere community with NGM. In this way, it can be assumed that transgenic rice Agb0103 could not influence phyllosphere microorganism community and environmental conditions.
This study investigated the effect of electron beam (EB) treatment on the microbial reduction of dried laver (Porphyra tenera) and identified EB-resistant bacteria from the treated dried laver. After EB treatments of 4 kGy and 7 kGy, the numbers of total bacteria and EB-resistant bacteria were measured using tryptic soy agar and mannitol salt agar, respectively. The morphological and biochemical characteristics of each isolated EB-resistant bacteria were investigated and these bacteria were identified. Compared to the control (1.5±0.2)×106 CFU/g, the total bacterial number was significantly decreased to (5.4±0.5)×104 CFU/g and (1.1±0.6)×104 CFU/g after EB treatments of 4 kGy and 7 kGy, respectively. With a higher EB dosage, the number of red colonies was almost same, whereas the number of yellow colonies was significantly decreased to (3.3±1.2)×103 CFU/g and 0 CFU/g for 4 kGy and 7 kGy, respectively. All red and yellow colonies were gram-positive cocci, catalase-positive, and resistant to 3% and 5% NaCl media. From the 16S rDNA sequence analysis, yellow and red colonies were identified as either Micrococcus flavus or M. luteus, with 99% similarity for the yellow colonies, and Deinococcus proteolyticus and D. piscis, with 99% and 97% similarity for the red colonies, respectively.
잔디는 스포츠 경기장, 골프장, 조경분야, 공원, 묘지, 사방건설, 개인주거지 등 광범위하게 활용되고 있는 고부가가치의 경제성 작물이다. 본 연구는 제초제저항성 들잔디 JG21의 화분(pollen)과 금잔디(Z. meliloti) 암술(carpel)의 종간 인공수분을 통해 육성된 제초제저항성 교배종 잔디 계통(JG21-MJ)의 분자생물학적 특성을 평가하기 위해 수행되었다. genomic Southern blot분석에서 제초제저항성 교배종 잔디들은 모두 bar 유전자가 확인되었고, JG21과 동일한 혼성화 패턴(hybridization pattern)을 보여 주었다. PCR을 이용하여 교배종 가운데 제초제저항성이 없는 대조군 품종과 제초제저항성 품종에서 도입유전자 주변염기서열을 분석하였다. 이 실험은 들잔디(JG21)와 금잔디의 교배(F1)와 자가수분(F2) 과정에서 도입유전자 삽입위치 주변의 염기서열에서 상동재조합이 발생하였는가를 조사하기 위해 수행하였다. 제초제저항성 교배종의 도입유전자 주변염기서열은 JG21과 동일하였고, 제초제저항성이 없는 대조군의 삽입위치 주변의 염기서열은 금잔디의 염기서열과 동일하였다.
가뭄저항성벼의 복수세대에 대한 후대안정성을 서던 분석과 PCR로 분석한 결과, 가뭄저항성벼의 Agb0103 T4~T6 세대에서는 도입된 모든 유전자들이 안정적으로 도입되어 있으며, T-DNA 구성요소 이외의 backbone DNA는 가뭄저항성벼에 삽입되지 않았음을 확인하였다. 목적 유전자인 CaMsrB2와 제초제 저항성 선발 마커인 bar 유전자가 가뭄저항성벼 Agb0103의 T4~T6 세대에서 안정적으로 발현됨을 검증하였다. 제초제 저항성 선발 마커로 도입된 PAT 단백질의 발현 분석 결과에서도 Agb0103 T4~T6의 3세대에서 생육시기별, 부위별로 안정적으로 발현됨을 입증하였다. 도입유전자의 삽입 위치를 확인한 결과, 가뭄저항성벼 Agb0103의 도입유전자가 벼 8번 염색체 내에서 intergenic한 상태로 안정적으로 유지되고 있음을 확인하였다. 이상의 분석 기법을 통해 복수세대에서 가뭄저항성벼의 도입 유전자들이 안정적으로 유지되고 목적 단백질들이 안정적으로 발현되고 있음을 확인하였다.
잔디는 비식용, 비사료용 작물이지만 스포츠공간용, 조경용, 지피용 등으로 전 세계적으로 가장 보편적으로 활용되는 작물이며, 경제성이 매우 높은 작물이다. 본 연구의 목적은 상업적 재배를 위해 개발된 제초제저항성 웅성불임 GM들잔디의 분자생물학적 특성을 평가하는 것이다. JG21-MS 웅성불임계통은 최초 선발된 해로부터 현재까지 6여 년 동안 제초제저항성 뿐만 아니라 웅성불임성을 잘 유지 하고 있다. BAR 유전자카세트와 T-DNA 삽입점에서 좌,우 1kb 정도의 주변 염기서열의 동등성 및 BAR유전자 발현의 동등성에서 모본과 차이를 보이지 않았다. T-DNA 삽입특성을 조사한 실험에서, T-DNA 오른쪽 경계(RB)의 삽입은 특이한 DNA단편의 첨가 또는 소실 없이 들잔디 DNA와 연결되어 있지만, hygromycin 저항성 유전자(HPH)가 위치한 왼쪽 경계(LB)의 삽입은 삽입과정에서 HPH 유전자의 4/5 정도가 소실되어 유전자의 기능을 상실하였다. 또한 왼쪽 끝 부분과 연결된 들잔디 DNA 쪽도 620bp가 소실되었다. T-DNA는 Ty1-copia retrotransposon-like 유전자 영역에 삽입 된 것으로 확인되었다. Ty1-copia retrotransposon은 식물 종에 조금 차이가 있지만 전체게놈의 10~50% 정도를 차지하는 것으로 알려져 있다. 또한 retrotransposon-like 유전자는 식물고유기능의 유전자가 아니므로 본 이벤트에서 T-DNA는 비유전자영역에 삽입된 것으로 간주할 수 있을 것으로 사료된다. 결국, JG21과 JG21-MS는 HPH 유전자가 소실되어 기능을 상실하였으므로 목표 유전자인 BAR 만 single copy로 존재하는 것으로 확인되었다. 차세대바이오그린21 GM작물실용화사업단에서 지원하는 GM작물 이벤트의 분자생물학적 특성의 최소기준은 단일복제수(single copy), 항생제마커 없이 목표유전자 도입(target gene only), 비유전자 내 삽입을 장려하고 있고, JG21와 JG21-MS 계통의 제초제저항성 들잔디는 이러한 기본조건을 만족시키고 있는 것으로 평가되었다.
Agronomic characteristics of transgenic herbicide-resistant rice lines were evaluated under field condition. Differences in agronomic traits and rice quality were observed between transgenic plants and the corresponding untransformed controls. Transgenic Ilpumbyeo lines flowered earlier than untransformed controls, whereas transgenic Nagdongbyeo flowered at the same time as untransformed control. With regard to the yield and rice quality, most of the transgenic lines showed lower yield than control except some selected transgenic lines. Selected Nagdongbyeo transgenic line also showed good eating quality comparable to the control although most selected Ilpumbyeo transgenic lines showed slightly lower eating quality and increased white center/belly in the rice grain. In order to find the main factor leading to somaclonal variation among transgenic lines, Tos17, a rice retrotransposon activated by prolonged tissue culture period was investigated. Although the transgenic lines carried only one or two of transformed bar gene, the copy number of Tos17 increased in most transgenic lines compared with control. The activation of Tos17 was not detected in selected promising transgenic lines such as ND115-15-1-B and IP23-3-3, suggesting that the increased copy number of Tos17 may have negatively affected agronomic characteristics of transgenic rice.