• 생명과학회지
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• 제20권6호
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• pp.929-933
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• 2010

본 연구는 곤충으로부터 새로운 항 진균 단백질을 발굴하기 하기 위한 목적으로 누에를 대상으로 Aspergillus niger의 감염을 유도하였을 때 발현되는 유전자의 특성을 분석한 것이다. Annealing control primer 법에 기초한 GeneFishing Kit를 사용하여 A. niger를 약 $6{\times}10^8$ colony per unit로 5령기 누에 유충의 체강에 감염시킨 후, 6시간 경과한 다음에 유도 발현되는 유전자(differentially expressed genes, DEGs)를 분석 한 결과, 10개의 유도 발현되는 유전자를 분리하였고 RT-PCR을 통해서 lysozyme, enbocin 그리고 한 개의 기능이 알려지지 않는 유전자등 3개의 유전자가 A. niger의 감염에 의해서 유의하게 과 발현된다는 것을 검증하였다. 일반적으로 그람 음성 및 양성 세균의 감염에 의해 유도된다고 알려진 enbocin 유전자가 A. niger의 감염에서도 과 발현이 유도되는 본 연구의 결과는 앞으로 enbocin 유전자의 항 진균 활성 연구에 중요한 기초 자료로 활용될 수 있을 것이다.

• 한국산림과학회지
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• 제59권1호
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• pp.121-142
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• 1983

Recently mycorrhizal research has been one of the most fast-growing research areas in modern plant science and microbiology. The application potential of mycorrhizal techniques to agriculture and forestry is enormous in view of the ubiquitous nature of mycorrhizae and known benefits of mycorrhizae to host plants. Unfortunately, very few scientists in Korea are currently involved in mycorrhizal research. When a team of American plant pathologists visited Korea in September 1982 to participate in the Korea-U.S.A. Joint Seminar on Forest Diseases and Insect Pests, they were surprised by the principal author's statement that there was no single research project on mycorrhizae sponsored by Korean government or any scientific institutions. The author initiated a few years ago a research project on the ecology of tree mycorrhizae with a foreign financial support. Major areas of interest were survey of ectomycorrhizae in relation to soil fertility, taxonomic distribution of mycorrhizae among woody plants, identification of ectomycorrhizal fungi, and growth response of woody plants to artificial inoculation. In spite of the enormous application potential of mycorrhizae to agronomic plants, the subject of mycorrhizae has not been recognized by Korean agronomists, foresters or pathologists. The purpose of this review rather written in Korean is to introduce the techniques of mycorrhizal research to Korean scientists and to urge them to participate in challenging new scientific field which might bring us a remarkable increase in crop productivity and tree growth through manipulation of this unique symbiosis. In this review, following topics were discussed in the same order: introduction; brief history of mycorrhizal research; morphology and classification of mycorrhizae; distribution of mycorrhizae in plant kingdom and in soil profile; physiology of mycorrhizae (functions, mineral nutrition, mycorrhizal formation); interaction of mycorrhizae with soil-born plant pathogens. mycorrhizae in nitrogen-fixing plants; application of mycorrhizal techniques to nursery practices (isolation, culture, inoculation, and response); prospect in the future.

• Entomological Research
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• 제48권5호
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• pp.384-389
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• 2018

Aphis gossypii Glover is an important insect pest that functions as a viral vector and mediates approximately 45 different viral diseases. As part of a strategy for control of A. gossypii, we investigated the functions of genes using RNAi. To this end, a cDNA library was constructed for various genes and for selecting appropriate targets for RNAi mediated silencing. The cDNA library was constructed using the Gateway cloning system with site-specific recombination of bacteriophage ${\lambda}$. It was used to carry out single step cloning of A. gossypii cDNAs. As a result, a cDNA library with a titer of $8.4{\times}10^6$ was constructed. Since the sequences in this library carry att sites, they can be cloned into various binary vectors. This library will be of value for various studies. For later screening of selected genes, it is planned to clone the library into virus-induced gene silencing (VIGS) vectors, which makes it possible to analyze gene function and allow subsequent transfection of plants. Such transfection experiments will allow testing of RNAi-induced insecticidal activity or repellent activity to A. gossypii, and result in the identification of target genes. It is also expected that the constructed cDNA library will be useful for analysis of gene functions in A. gossypii.

• The Plant Pathology Journal
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• 제38권4호
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• pp.287-295
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• 2022

Citrus tristeza virus (CTV) is efficiently transmitted in a semi-persistent manner by the brown citrus aphid (Toxoptera citricida (Kirkaldy)). Currently, the most sensitive method for detecting plant viruses in insect vectors is reverse-transcription quantitative polymerase chain reaction (RT-qPCR). In this study, the elongation factor-1 alpha (EF-1α) gene and acidic p0 ribosomal protein (RPAP0) gene were confirmed to be suitable reference genes for RT-qPCR normalization in viruliferous T. citricida aphids using the geNorm, NormFinder, and BestKeeper tools. Then the relative CTV titer in aphids (T. citricida) at different post-acquisition feeding times on healthy plants was quantified by RT-qPCR using EF-1α and RPAP0 as reference genes. The relative CTV titer retained in the aphids gradually decreased with increasing feeding time. During the first 0.5 h of feeding time on healthy plants, the remaining CTV titer in aphids showed about 80% rapid loss for the highly transmissible isolate CT11A and 40% loss for the poorly transmissible isolate CTLJ. The relative CTV titer in aphids during more than 12 h post-acquisition times for CT11A was significantly lower than at the other feeding times, which is similar to the trend found for CTLJ. To our knowledge, this is the first report about the relative titer variation of CTV remaining in T. citricida at different post-acquisition feeding times on healthy plants.

• Journal of the Korean Wood Science and Technology
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• 제31권2호
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• pp.52-57
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• 2003

본 연구에서는 목조 고건축물의 하나인 향교를 대상으로 곤충류의 활동이 활발한 시기인 2001년 3월부터 9월에 걸쳐 외부 기둥 표면이나 이미 발생한 탈출공 내부 및 주변에 붙어 있는 곤충을 채집하여 분류, 동정하였고, 이들의 목조 고건축물 가해충 여부를 고찰하였다. 채집된 곤충은 딱정벌레목(Coleoptera) 10종, 벌목(Hymenoptera) 15종, 노린재목 (Hemiptera) 6종, 파리목(Ditera) 4종, 그리고 집게벌레목(Demaptera) 1종으로 동정되었다. 이 중 포획종과 개체수가 가장 많은 딱정벌레목과 벌목의 대부분은 구기가 저작형이며 강대한 턱을 가지고 있어 목조 건축물에 상당한 피해를 줄 것으로 생각된다. 앞으로 채집된 곤충 중 어떤 종류가 목재 가해 충류인지와 가해충류로 최종 확인된 충류의 계속적인 연구가 필요하다고 사료된다.

• International Journal of Computer Science & Network Security
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• 제23권9호
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• pp.77-90
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• 2023

Today, crops face many characteristics/diseases. Insect damage is one of the main characteristics/diseases. Insecticides are not always effective because they can be toxic to some birds. It will also disrupt the natural food chain for animals. A common practice of plant scientists is to visually assess plant damage (leaves, stems) due to disease based on the percentage of disease. Plants suffer from various diseases at any stage of their development. For farmers and agricultural professionals, disease management is a critical issue that requires immediate attention. It requires urgent diagnosis and preventive measures to maintain quality and minimize losses. Many researchers have provided plant disease detection techniques to support rapid disease diagnosis. In this review paper, we mainly focus on artificial intelligence (AI) technology, image processing technology (IP), deep learning technology (DL), vector machine (SVM) technology, the network Convergent neuronal (CNN) content Detailed description of the identification of different types of diseases in tomato and potato plants based on image retrieval technology (CBIR). It also includes the various types of diseases that typically exist in tomato and potato. Content-based Image Retrieval (CBIR) technologies should be used as a supplementary tool to enhance search accuracy by encouraging you to access collections of extra knowledge so that it can be useful. CBIR systems mainly use colour, form, and texture as core features, such that they work on the first level of the lowest level. This is the most sophisticated methods used to diagnose diseases of tomato plants.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제5권1호
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• pp.10-20
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• 2024

The study investigated species diversity, relative abundance, and decline of flying insects and plants within a fragmented forest in the Federal University of Technology Akure (FUTA), Ondo State, Nigeria. It is known that habitat fragmentation can reduce biodiversity. Thus, it is important to perform comprehensive assessments to understand implications of the habitat fragmentation for flora and fauna. Species richness and abundance of flying insects and plants across fragmented forest patches were quantified using field surveys and taxonomic identification. This study revealed shifts in species diversity, with fragmented areas exhibiting reduced biodiversity compared to contiguous forest ecosystems. Flying insects crucial for ecosystem functioning and pollination services demonstrated decreased species richness and relative abundance within fragmented habitats. This decline was attributed to habitat loss, altered microclimates, and limited movement pathways known to hinder insect dispersal. Similarly, plant species richness and abundance showed decline in fragmented forest due to disrupted mutualistic interactions with pollinators, altered nutrient cycling, and increased competition among plant species. This study underscores the importance of maintaining intact forest habitats to sustain healthy ecosystems and preserve biodiversity. Effective conservation strategies should focus on habitat connectivity, reforestation efforts, and protection of essential ecological corridors to mitigate effects of fragmentation. In conclusion, this investigation provides empirical evidence for effects of habitat fragmentation on flying insects and plants in a forest ecosystem in FUTA Akure, Nigeria. Findings emphasize an urgency of adopting conservation measures to safeguard these invaluable components of biodiversity and ecosystem stability in the face of ongoing habitat loss and fragmentation.

• Journal of Ginseng Research
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• 제20권4호
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• pp.472-500
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• 1996

Researches on mineral nutrition, physiology and phyrsiological diseases, . cultivaction methods. brceding. pest control quality management and extension during 1976-1995 in Korea were reviewed Review in brceding and pest control was restricted to the researches directely related to cultivaction. Mineral nulrient up take. partion and varicos factors such as top dreasing. Light intersity etc. and interrelationship between minerals were investigated. Top dressing was not effective due to low minera1 requorement Physiological characteristics on tempelature light and water were well elucidated and applied to assess traditional cultivation method and its inovation. Photosyrnthetic pigments. light harvest proteins and activity of related enzymes were studied. In nitrogen metabolism arginine, praline, ammonium, threonine appeared to have important role in re growth of shoot Saponin metabolism was studied in relation to growth and new ginsenosides were found but physiological role of saponin was not clearly elucidated yet Endogenous growth regulators were reported and various erogenous growth regulators were studied for growth stimulation. short stem and seed pruning etc. Various physiological diseases were investigated for cause and control measures were established. Water culture was little studied Forest culture was studied but not retched the recommendable stage Drip irrigation straw mulching. seasonal shading and soil preparation method including soil fertility adjustment were established for practical application. Shading materials completely changed to polyethylene net and materials of polymers The research on ginseng cultivation in paddy field opened the way to establish the permanent ginseng cultivation plantation Ginseng harvester and seeder were developed in the late 1950s. Transplanted and many other machines were developed in the early 1990s. In ginseng breeding only pure line selection was of practical significance several verities were at the stage of seed propagation at ginseng plantations. Mutation breeding (${\gamma}$-ray. X-ray chemicals) was not successful. The research on plantlet formation through tissue culture was a little progressed but still far behind to vegetative propagation. Disease control research was concentrated in the isolation and identification of pathogans. their ecological charactelistics and biological control and soil humigation. Potato root rot nematodes was found and control method was established. Insect and small animal control research was greatly progresses in identification, ecological investigation, and ecological and physical control. Weed control was less important due to the development of mulching method of ridge and ditch. Quality factors of raw ginseng in relation to red ginseng process were extensively studied. Traditional quality measures were elucidated in accordance with modern analytical chemistry resulting in the importance of peptides in the centrat part rather than ginsenosides For large root production growth promoting rootzone micrcorganisms (PGPRM) were isolated and active compounds were identified. Field test on PGPRM was on going. Varictus methods formality improvement through cultivation were developed. Management research of ginseng production was rare Extension was active throuch official and private organizations and through workshop for the extension specialists, and direct lectures to grower's. Extension services made the researcher to understand the existing problems at grower's fields. Research environment for ginseng production was in prime time only for three years when Korea Ginseng Research Institute was established then gradually aggravated.

• 한국산림과학회지
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• 제112권1호
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• pp.40-56
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• 2023

사시나무속 수종은 생장이 빠르고 우수한 탄소흡수 능력을 보여주며, 환경정화 효과가 큰 수종으로 이상기후 및 환경오염 문제에 대응하는 기후적응성 품종개발 및 육종집단 조성에 적합하다. 따라서 유전연관지도 작성 및 양적형질 유전자좌 탐색을 통하여 포플러 육종을 신속하게 진행할 수 있을 것이다. 본 연구에서는 차세대 염기서열 분석기술 방법인 genotyping-by-sequencing 기법을 이용해 인공교배 차대에 대한 고밀도 유전연관 지도를 작성하였다. 또한 사시나무의 수고와 근원경 생장 그리고 해충피해에 대한 회복력 형질을 조사하여 유전연관지도에 위치한 양적형질 유전자좌를 탐색하였다. 서울대학교 학술림에 조성된 사시나무 4년생 육종집단(오대19 × 봉현4 인공교배 차대집단)에서 수고 및 근원경 생장을 조사하였으며, 식엽성 해충인 꼬마버들재주나방 유충의 피해를 받은 후 이에 대해 회복 능력을 조사하였다. 잎 시료의 DNA 추출 후 5개 microsatellite 마커를 이용하여 유전자형을 확인하였으며 친자로 확인된 개체만을 연구재료로 사용하였다. 친자 확인이 완료된 시료의 DNA는 제한효소를 이용해 절단하였으며, 이렇게 얻은 DNA 조각들은 GBS 라이브러리로 제작하여 염기서열을 분석하였다. 분석된 결과는 Populus trichocarpa를 참조유전체로 하여 정렬하였다. 정렬된 SNP 마커는 총 58,040개였으며, 그 가운데 17,755개의 SNP 마커를 유전연관지도 작성에 사용하였다. 유전연관지도는 19개의 연관군으로 나누어졌으며, 전체 길이는 2,129.54 cM으로 나타났다. 조사된 세 가지 형질에 대한 양적형질 유전자좌 분석을 실시한 결과, 수고와 근원경 생장과 연관된 양적형질 유전자좌는 찾을 수 없었으나 전장유전체연관연구(GWAS)를 통하여 4번 연관군(염색체)에 해충피해 회복력과 관련이 있을 것으로 추정되는 유전자를 확인하였다.

• 미생물학회지
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• 제48권4호
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• pp.284-292
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• 2012

파밤나방(Spodoptera exigua)은 유기합성 농약을 이용한 화학 살충제 외에 뚜렷한 방제방법이 알려져 있지 않으나, 그에 대한 저항성과 더불어 식물을 가해하는 방법에 있어 그들만의 독특한 숙주 가해습성으로 인해 난방제 해충으로 알려져 있다. 화학살충제에 대한 저항성의 해결을 위하여 곤충병원성 바이러스 및 세균을 이용한 살충제가 개발되어 있으나, 이들 역시 파밤나방 유충이 줄기 속으로 들어가는 가해습성으로 인하여 효과적이지 못한 실정이다. 그러므로 본 연구에서는 그들의 가해습성과 저항성을 극복할 수 있는 새로운 방제원으로써, 체벽과의 일시적인 접촉을 통해 살충성을 발휘할 수 있는 파밤나방에 대한 병원성 곰팡이를 분리하고 그 특성 및 살충성을 조사하였다. 파밤나방 병원성 곰팡이는 파밤나방 누대사육 중 곰팡이병 증상을 보이며 이병된 사충으로부터 분리하였으며, 분리 곰팡이는 배지에서의 증식상 및 현미경적 관찰을 통한 형태학적 동정과 더불어 ITS, ${\beta}$-tublin 및 EF1-${\alpha}$ 부분의 염기서열 분석을 통해 Nomuraea rileyi로 최종 동정하고 N. rileyi SDSe로 명명하였다. 분리 균주의 파밤나방에 대한 살충력 검정은 $1{\times}10^4-10^8conidia/ml$까지의 다양한 포자현탁액에 파밤나방 3령 유충을 침지하는 조건으로 수행한 결과, 20-54%의 살충률을 나타냈으며 포자현탁액의 농도가 증가할수록 살충력도 증가하는 양상을 나타냈다. 본 연구결과 분리된 N. rileyi 균주가 비록 높은 살충력을 보이지 않았으나, 파밤나방이 난방제 해충임을 감안할 때 다른 방제방법과 함께 종합적 해충 방제 방법에 있어 효과적인 방제수단의 일환이 될 수 있을 것으로 기대된다.