• 제목/요약/키워드: diseases and insect pests

검색결과 209건 처리시간 0.019초

A New Record of Candida kashinagacola (Synonym Ambrosiozyma kashinagacola) from Galleries of Platypus koryoensis, the Oak Wilt Disease Vector, in Korea

  • Suh, Dong Yeon;Kim, Seong Hwan;Son, Seung Yeol;Seo, Sang Tae;Kim, Kyung Hee
    • Mycobiology
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    • 제41권4호
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    • pp.245-247
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    • 2013
  • The ambrosia beetle, Platypus koryoensis, is an economically important pest affecting oak trees in Korea. Candida kashinagacola was isolated from galleries of the beetle in oak wood and identified by analyses of morphology, physiological properties, and nucleotide sequence of the large subunit ribosomal DNA. This is the first report on Candida species associated with oak wilt disease vectored by the ambrosia beetle, Platypus koryoensis, in Korea.

Macruropyxis fraxini on Fraxinus rhynchophylla: Confirmation in the Korean Peninsula after 82 Years and the First Record in South Korea

  • Jung, Bok-Nam;Choi, Young-Joon;Shin, Hyeon-Dong;Park, Ji-Hyun
    • Mycobiology
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    • 제48권6호
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    • pp.518-521
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    • 2020
  • Macruropyxis fraxini has been recorded on several species of Fraxinus in China, Japan, Russia (Far East), and North Korea since its first recorded observation as a rust fungus on F. rhynchophylla in Jilin, China, in 1899. In the Korean Peninsula, the rust fungus was first recorded on F. rhynchophylla in 1935, based on four specimens collected at Mt. Kumgangsan, Gangwondo Province, in the North Korean territory. We confirmed this rust in the Korean Peninsula after 82 years. The rust fungus was identified based on morphological characteristics and a molecular phylogenetic analysis. This is the first record of M. fraxini in South Korea.

Question Similarity Measurement of Chinese Crop Diseases and Insect Pests Based on Mixed Information Extraction

  • Zhou, Han;Guo, Xuchao;Liu, Chengqi;Tang, Zhan;Lu, Shuhan;Li, Lin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제15권11호
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    • pp.3991-4010
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    • 2021
  • The Question Similarity Measurement of Chinese Crop Diseases and Insect Pests (QSM-CCD&IP) aims to judge the user's tendency to ask questions regarding input problems. The measurement is the basis of the Agricultural Knowledge Question and Answering (Q & A) system, information retrieval, and other tasks. However, the corpus and measurement methods available in this field have some deficiencies. In addition, error propagation may occur when the word boundary features and local context information are ignored when the general method embeds sentences. Hence, these factors make the task challenging. To solve the above problems and tackle the Question Similarity Measurement task in this work, a corpus on Chinese crop diseases and insect pests(CCDIP), which contains 13 categories, was established. Then, taking the CCDIP as the research object, this study proposes a Chinese agricultural text similarity matching model, namely, the AgrCQS. This model is based on mixed information extraction. Specifically, the hybrid embedding layer can enrich character information and improve the recognition ability of the model on the word boundary. The multi-scale local information can be extracted by multi-core convolutional neural network based on multi-weight (MM-CNN). The self-attention mechanism can enhance the fusion ability of the model on global information. In this research, the performance of the AgrCQS on the CCDIP is verified, and three benchmark datasets, namely, AFQMC, LCQMC, and BQ, are used. The accuracy rates are 93.92%, 74.42%, 86.35%, and 83.05%, respectively, which are higher than that of baseline systems without using any external knowledge. Additionally, the proposed method module can be extracted separately and applied to other models, thus providing reference for related research.

우리나라에서의 신농약 개발전망 (Feasibility of New Pesticide Development in Korea)

  • 박영선
    • 한국응용곤충학회지
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    • 제22권2호
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    • pp.84-97
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    • 1983
  • Under the limited arable land, the enhancement of agricultural productivity is indispensable to provide the food demand which is concomitant with the rapid increase in population. From this viewpoint, the upbringing and dissemination of high-yielding varieties has been promoted continuously and several modifications in cultural practices, including heavy fertilization, dense planting, and early transplanting, also have been gradually developed. However these changes in cultivation have led to the increased outbreak of insect pests and diseases. And this unexpected results have accelerated the number and complexity of pesticides employed as well as their consumption. Even though pesticides are essential materials contributing to the steady production of agricultural crops, large scale consumption of them has given rise to several adverse impacts, such as mammalian hazard and/or environmental contamination. In this respect, recent development of new pesticides has been concentrated on 'safe pesticide', as it were, that has the highly selective properties without unfavorable side influences on other ecosystem. According to literature cited up to now, feasibilities of safe pesticide development would be summarized as two categories. One of them is the development of chemical pesticides, which include the molecular structure modification of established pesticides for increased safety and synthesis of new safe chemicals which can attack the vulnerable point of physio-ecological characteristics in insect pests and diseases. The other is the biological pesticides which comprise natural enemies and microorganisms to act selectively on confined insect pests and diseases, In addition, improvement of physico-chemical properties of available pesticide formulations would be one of the desirable means for safe pesticide development in view of efficacy enhancement and minimization of hazardous properties or safe pesticide development, various approaches are feasible and needed to study, however, long period and much financial outlay are necessary to develop a new item. And under the present situation in Korea, there are many difficulties for performing research on all the possible routes. Therefore, combined pesticides by the reasonable combination of already registered resticides evaluated as the fairly safe pesticides and safe formulation based on their physico-chemical properties would be developed primarily. And many efforts would be given gradually for the development of new chemical and biological pesticides.

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In vitro Inhibition of Fungal Root-Rot Pathogens of Panax notoginseng by Rhizobacteria

  • Guo, Rongjun;Liu, Xingzhong;Li, Shidong;Miao, Zuoqing
    • The Plant Pathology Journal
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    • 제25권1호
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    • pp.70-76
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    • 2009
  • The rhizobacteria of Panax notoginseng were isolated from six sites in Yanshan, Maguan and Wenshan Counties, Yunnan Province of China, and their antagonistic activity against P. notoginseng root-rot fungal pathogens was determined. Of the 574 rhizobacteria isolated, 5.8% isolates were antagonistic in vitro to at least one of the five pathogens, Cylindrocarpon didynum, Fusarium solani, Phytophthora cactorum, Phoma herbarum, and Rhizoctonia solani. The number of rhizo bacteria and the number that inhibited fungi differed depending on sampling sites and isolation methods. Rhizobacteria isolated from the site in Yanshan and Maguan showed more antagonistic effect than them in Wenshan. Heat treatment of rhizosphere soil at $80^{\circ}C$ for 20 min scaled the antagonists up to 14.0%. Antagonistic bacteria in the roots proportioned 3.9% of the total isolates. The most antagonistic isolates 79-9 and 81-4 are Bacillus subtilis based on their 168 rDNA sequence and biochemical and physiological characteristics. Identification and evaluation of antagonistic bacteria against P. notoginseng root-rot pathogens in the main planting areas improved our understanding of their distribution in rhizosphere soil. Furthermore these results indicated that the interactions between biocontrol agent and soil microbes should be seriously considered for the successful survival and biocontrol efficacy of the agents in soil.

Inhibition of Citrate Synthase Thermal Aggregation In Vitro by Recombinant Small Heat Shock Proteins

  • Gong, Weina;Yue, Ming;Xie, Bingyan;Wan, Fanghao;Guo, Jianying
    • Journal of Microbiology and Biotechnology
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    • 제19권12호
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    • pp.1628-1634
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    • 2009
  • Small heat shock proteins (sHSPs) function as molecular chaperones that protect cells against environmental stresses. In the present study, the genes of hsp17.6 and hsp17.7, cytosolic class I sHSPs, were cloned from a tropical plant, Ageratina adenophorum. Their C-terminal domains were highly conserved with those of sHSPs from other plants, indicating the importance of the C-terminal domains for the structure and activity of sHSPs. The recombinant HSP17.6 and HSP17.7 were applied to determine their chaperone function. In vitro, HSP17.6 and HSP17.7 actively participated in the refolding of the model substrate citrate synthase (CS) and effectively prevented the thermal aggregation of CS at $45^{\circ}C$ and the irreversible inactivation of CS at $38^{\circ}C$ at stoichiometric levels. The prior presence of HSP17.7 was assumed to suppress the thermal aggregation of the model substrate CS. Therefore, this report confirms the chaperone activity of HSP17.6 and HSP17.7 and their potential as a protectant for active proteins.

두릅나무 묘목생산포의 역병 발생 및 분리균의 균학적 특성 (Root Rot of Japanese Angelica Caused by Phytophthora cactorum in Nursery and Mycological Characteristics of the Isolates)

  • 이상현;이재필;김경희;신현동
    • 한국균학회지
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    • 제33권2호
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    • pp.98-102
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    • 2005
  • 2003년부터 2005년 사이에 한국의 두릅나무에 심각한 역병이 발생하였다. 감염된 두릅나무와 토양으로부터 병원균이 분리되었으며, 이 균은 배양적인 그리고 형태적인 특징 및 병원성 검증 실험에 의해 P. cactorum(Lebert&Cohn) J. Schrt.으로 동정되었다. 이 균은 뚜렷한 돌출형이고, 둥근 난형모양의 탈락성 유주포자낭의 특정으로 다른 역병균으로부터 형태적으로 구분되었다. 최적의 생장 온도는 V8 배지와 Oat meal 배지에서의 $25^{\circ}C$이었다. PCR을 통해 ITS rDNA 영역의 약 900 bp의 길이가 증폭되었으며, 세 가지 효소인 Alu I, Msp I, Taq I을 이용한 PCR-RFLP 분석 결과를 PhytID 의 데이터베이스에서 분석한 결과 형태적인 그리고 배양적인 특징에 의한 결과와 일치했다.

살균제 나무주사를 이용한 참나무 시들음병 방제 효과 (Control Efficacy of Fungicide Injection on Oak Wilt in the Field)

  • 손수연;서상태;박지현
    • 식물병연구
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    • 제20권4호
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    • pp.295-298
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    • 2014
  • 참나무 시들음병(병원균 Raffaelea quercus-mongolicae)은 2004년 국내에 처음 발견되어 그 피해가 증가하고 있는 추세이다. 이번 연구에서는 참나무 시들음병 방제를 위한 나무주사용 살균제를 선발하기 위해 실내시험과 포장시험을 실시하였다. 실내검정에서는 10종의 살균제와 1종의 항생제를 이용하여 국내균주 R. quercus-mongolicae와 일본균주 R. quercivora에 대한 생육억제효과를 조사하였다. 국내균주에 대해서는 chlorothalonil, benomyl, propiconazole 순으로 생육억제효과가 높게 나타났으며, 일본균주에 대해서는 propiconazole, benomyl, bitertanol 순으로 나타났다. 국내균주와 일본균주에 대하여 실내 항균효과가 우수하였던 약제 중 침투이행성이 우수한 propiconazole을 이용하여 약제방제 포장시험을 실시하였다. 그 결과 나무주사 처리 당해 연도 방제효과는 87.5%, 처리 다음 연도 방제효과는 66.7%까지 나타나 약제처리 효과는 적어도 1년 이상이었다.

형태 특징 및 분자 분석에 의한 산철쭉 흰가루병균 Erysiphe izuensis 동정 (Identification of Erysiphe izuensis on Rhododendron yedoense f. poukhanense in Korea Based on Morphological and Molecular Characteristics)

  • 조성은;이상현;이선근;서상태;신현동
    • 한국균학회지
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    • 제46권1호
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    • pp.69-74
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    • 2018
  • 진달래속의 흰가루병균인 Erysiphe izuensis는 중국, 일본, 한국, 러시아 등 아시아에서만 기록되어있다. 한국에서는 무성세대의 형태적 특징에 의해, 도입된 진달래속 식물에서 E. izuensis가 기록되었다. 최근에 저자들은 산철쭉에서 흰가루병균을 국내에서 처음으로 채집하였다. 본 연구를 통하여 국내에서 E. izuensis의 유성세대의 형태적 특징과 internal transcribed spacer 염기서열을 처음으로 제공하였다. 게다가, 이 종에서 그 동안 알려지지 않았던 1차 분생포자와 분생포자의 표면구조 등 무성세대의 형태적 특징을 처음으로 기재하였다.

참싸리 겹둥근무늬병균 Grovesinia moricola 동정 (Identification of Grovesinia moricola Causing Zonate Leaf Spots on Lespedeza cyrtobotrya in Korea)

  • 박지현;정복남;이상현;신현동
    • 한국균학회지
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    • 제48권1호
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    • pp.69-74
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    • 2020
  • 2017년 9월 춘천의 오봉산에서 참싸리 잎에 겹둥근무늬가 생기고 조기낙엽이 일어나는 등 큰 피해가 발견되었다. 병든 잎의 뒷면에는 원뿔형의 흰색 포자과가 다수 발견되었다. 2019년 9월 횡성의 태기산에서도 참싸리 잎에서 유사한 증상이 발견되었다. 이러한 증상에서 발견된 포자과의 형태적 특징으로 보아 이 곰팡이는 Grovesinia moricola와 일치하였다. 확보된 두 균주(KACC48417 및 KACC48934)의 ITS rDNA 염기서열 분석을 통해 동정을 확인하였다. 이 곰팡이의 병원성은 상대습도 100%와 15±2℃의 조건에서 인공접종을 통하여 확인하였다. 이는 한국에서 참싸리와 G. moricola의 관계를 연구한 최초의 보고이다.