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        검색결과 119

        41.
        2016.04 구독 인증기관·개인회원 무료
        Entomopathogenic fungi are natural enemies of insect pests and contribute to the natural regulation of their host populations. These fungal group are often used as active ingredients for microbial insect pest control. In addition, the potential antimicrobial effect by entomopathogenic fungi including Beauveria bassiana, Lecanicillium spp., and Isaria fumosorosea have recently been reported against fungal plant pathogens. Dual microbial control effects with entomopathogenic fungi against both aphids and cucumber powdery mildew had reported in Canada. In our previous studies we conducted bioassay with entomopathogenic fungi to develop dual microbial control agent which can control both aphid and fungal plant disease. We selected an Beauveria bassiana isolate which has high dual control effects against both cotton aphid, Aphis gossypii and sclerotinia rot, Sclerotinia sclerotiorum. In this study, we have tested the dual control efficacy of the B. bassiana isolate against cotton aphid and sclerotinia rot on whole potted cucumber plants. We found that the B. bassiana isolate protected the plant from cotton aphid and sclerotinia rot under laboratory condition.
        42.
        2015.11 구독 인증기관·개인회원 무료
        The button mushroom, Agaricus bisporus, is one of the major economical crops cultivated in Korea. This mushroom showed the 5th production to 11,493 M/T in 2014. Several fungus are known as the causal agents of diseases of the cultivated button mushroom (Agaricus bisporus) and oyster mushroom (Pleurotus ostreatus). Cladobotryum mycophilum is the causal agent of cobweb disease of commercial mushrooms. Early symptoms were noticed as round, fleshy, yellowish brown lesions on mushroom caps. Late symptoms progressed when the parasitic fungus formed white cobweb circular colonies on dead or damaged pinheads, spread on the surface of the casing, and covered entirely fruiting bodies. A Gram-positive bacterium was isolated from mushroom media that markedly showed the antagonistic activity against Cladobotryum mycophilum, the most destructive pathogen of cultivated mushrooms. The HC57 strain was selected as antagonistic bacterium by inhibition zone method and it was identified as Bacillus subtilis by the cultural, morphological and physiological characteristics, and analysis of the 16S rDNA. The isolated bacterium is saprophytic but not parasitic nor pathogenic to cultivation mushroom. The isolated bacterium for Cladobotryum mycophilum cell, was sufficient for inhibition in vitro. Inoculation of the isolated bacterium prevents the development of bacterial disease in Cladobotryum mycophilum. Control efficacy of browning disease of strain HC57 treatment was 71% on Agaricus bisporus. The optimal culture medium for the antagonistic bacteria growth was determined as follows: 1.5% Xylose, 2% Soytone, 1% NH4H2PO4, 7 mmol CaCl2, and 0.5% Histidine at pH 6.0 at 25℃. The suppressive bacterium may be useful in future for the development of biocontrol system and the construction of genetically modified edible fungi resistant to the disease caused by Cladobotryum mycophilum.
        45.
        2015.04 구독 인증기관·개인회원 무료
        Ticks are obligatory ectoparasites of many vertebrates and transmit pathogens causing diseases such as Heartland virus and Ehrlichiosis. The lone star tick, Ambloyomma americanum L., is the primary vector of Ehrlichia chaffeensis, which causes human monocytic Ehrlichiosis. We aimed to investigate the genomic levels of gene regulation in the processes of acquiring the pathogen and of immune to pathogen. We designed six experimental groups: E. chaffeensis positive and negative groups of males and females, and pathogen free male and female ticks. Illumine HiSeq 2500 sequenced six libraries with 100-cycle single direction. Raw sequence reads (more than 209 million) were trimmed and filtered based on minimum quality score (Q-value >30) and size (> 40nt) for de novo assembly. Assembly using Trinity pipeline produced 140,574 contigs from trimmed and filtered sequence reads (about 117 million reads, 56% of raw data). For quality control of the de novo assembly of transcripts, we filtered out the sequences for mitochondrial, E. chaffeensis, and transposable elements sequences, and tested for contig redundancy and gap separations of the assembled sequences. RSEM and edgeR analyses of 61,802 contigs for identifying differentially expressed genes were followed by Blast2GO analyses for annotations of contigs and enriched-gene ontology (GO) term analyses in pairwise comparisons of the libraries. Further investigation of major groups of genes induced by pathogen would provide better understanding of pathogen-vector interaction, which will allow us to prevent of pathogen transmission by interrupting interaction between pathogen and ticks.
        46.
        2015.04 구독 인증기관·개인회원 무료
        The purpose of this multiplex PCR assay is establishment and application for rapid and simultaneous detection of six pathogens related with insect diseases. Five pathogens were chosen based on the insect disease incidence rate in South Korea and specific primers of those pathogen were designed to detect insect diseases and test multiplex PCR for detecting Fungi; Beauveria bassiana(Bb), Metarhizium anisopliae(Ma), Bacteira; Bacillus thuringiensis(Bt), Pseudomonas aeruginosa(Pa), and Serratia marcescens(Sm). This research carried out the results detecting five kinds of insect pathogen of P. b. seulensis by multiplex PCR. Multiplex PCR is effective and save time to detect simultaneously these insect pathogens and multiple infections to prevent insect disease. In our study, using multiplex PCR, we demonstrated that P. b. seulensis was frequently infected with S. marcescens and co-infected with M. anisopliae in more than 80% of cases, indicating that such an analysis can be useful for pathogen identification, especially if different pathogens produce similar symptoms.
        47.
        2014.11 구독 인증기관·개인회원 무료
        In the past two decades, European ash trees (Fraxinus spp.) have been severely damaged by ash dieback disease of which causal agent is a fungal species called Hymenoscyphus fraxineus (anamorphic stage Chalara fraxinea). Recent molecular phylogenetic and population genetic studies suggested that this fungus may have been introduced from Eastern Asia to Europe. In the course of fungal biodiversity survey in Korea, H. fraxineus-like apothecia were collected from fallen leaves, rachis and petioles of Korean ash and Manchurian ash trees. The morphological and ecological traits of these materials are provided, supplemented by ITS rDNA sequence comparison of H. fraxineus strains collected from Europe, China and Japan.
        48.
        2014.11 구독 인증기관·개인회원 무료
        The button mushroom, Agaricus bisporus, is one of the major economical crops cultivated in Korea. This mushroom showed the 5th production to 10,996 M/T in 2012. Several fungus are known as the causal agents of diseases of the cultivated button mushroom (Agaricus bisporus) and oyster mushroom (Pleurotus ostreatus). Cladobotryum mycophilum is the causal agent of cobweb disease of commercial mushrooms. Early symptoms were noticed as round, fleshy, yellowish brown lesions on mushroom caps. Late symptoms progressed when the parasitic fungus formed white cobweb circular colonies on dead or damaged pinheads, spread on the surface of the casing, and covered entirely fruiting bodies. A Gram-positive bacterium was isolated from mushroom media that markedly showed the antagonistic activity against Cladobotryum mycophilum, the most destructive pathogen of cultivated mushrooms. The HC7 strain was selected as antagonistic bacterium by inhibition zone method and it was identified as Bacillus altitudinis. by the cultural, morphological and physiological characteristics, and analysis of the 16S rDNA. The isolated bacterium is saprophytic but not parasitic nor pathogenic to cultivation mushroom. The isolated bacterium for Cladobotryum mycophilum cell, was sufficient for inhibition in vitro. Inoculation of the isolated bacterium prevents the development of bacterial disease in Cladobotryum mycophilum. Control efficacy of browning disease of strain HC7 treatment was 78% on Agaricus bisporus. The optimal culture medium for the antagonistic bacteria growth was determined as follows: 3% Soluble startch, 10% Soytone, 1% (NH4)2HPO4, 1 mmol KCl, and 0.5% L-asparagin at pH 6.0 at 30°C. The suppressive bacterium may be useful in future for the development of biocontrol system and the construction of genetically modified edible fungi resistant to the disease caused by Cladobotryum mycophilum.
        49.
        2014.06 구독 인증기관·개인회원 무료
        The button mushroom, Agaricus bisporus, is one of the major economical crops cultivated in Korea. This mushroom showed the 5th production to 10,996 M/T in 2012. Several bacteria are known as the causal agents of diseases of the cultivated button mushroom (Agaricus bisporus) and oyster mushroom (Pleurotus ostreatus). Pseudomonas agarici is the causal agent of browning disease of commercial mushrooms. Colonization of mushroom caps by the bacterium results in development of browning lesions on pileus. These lesions are superficial brown spots and can be round or spreading. But P. agarici never caused sunken lesions and rotting of the mushroom tissues. A Gram-positive bacterium was isolated from mushroom media that markedly showed the antagonistic activity against Pseudomonas agarici, the most destructive pathogen of cultivated mushrooms. The HC42 strain was selected as antagonistic bacterium by inhibition zone method and it was identified as Bacillus safensis. by the cultural, morphological and physiological characteristics, and analysis of the 16S rDNA.. The isolated bacterium is saprophytic but not parasitic nor pathogenic to cultivation mushroom. The isolated bacterium for P. agarici cell, was sufficient for inhibition in vitro. Inoculation of the isolated bacterium prevents the development of bacterial disease in Agaricus bisporus. Control efficacy of browning disease of strain HC42 treatment was 66% on Agaricus bisporus. The optimal culture medium for the antagonistic bacteria growth was determined as follows: 1.5% D-galactose, 1.5% yest extract, 1% NH4Cl, 1.5% KCl, and 1.0% L-asparagin at pH 6.0 at 25℃. The suppressive bacterium may be useful in future for the development of biocontrol system and the construction of genetically modified edible fungi resistant to the disease caused by P. agarici.
        50.
        2014.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 Colletotrichum 속에 따른 친환경 자재들의 고추 탄저병 방제 효과 차이를 구명하고자 수행하였다. 포자 발아억제 효과는 가용성 황과 BP 혼합 미생물 제제가 각각 90.4 - 99.3%와 83.4 - 96.6%를 나타내어 가장 효과적이었다. 균사 생육 억제 효과는 BP 미생물 제제가 83.5 - 98.3%로 가장 효과적이었다. 무상처 과실의 예방 효과는 수산화동이 85.5 - 93.1%, 상처 낸 과실의 예방 효과는 가용성 황이 75.4 - 79.5%로 가장 효과적이었다. 무상처 과실의 치료 효과는 가용성 황이 70.3 - 74.1%, 상처 낸 과실의 치료 효과는 C. dematium과 C. acutatum에서 30% 내외의 미미한 치료효과가 있었지만 다른 친환경 자재들은 그 효과가 없었다. 두 기내 실험에서 Colletotrichum 속에 따른 친환경 자재의 방제 효과가 대부분의 처리구에서 확인되었다. 포자 발아와 균사 생육의 억제 효과가 친환경 자재 특히 BP 혼합 미생물 제제에서 C. gloeosporioides이 높았고 C. capsici이 낮게 나타나 Colletotrichum속 간의 차이를 보였다. 고추 과실에서 Colletotrichum 속에 따른 친환경 자재의 방제 효과를 보면, 두 기내실험과 달리 일부에서 확인되었다. 무상처 과실의 예방 효과가 확인된 수산화동과 가용성 황 처리구에서 C. dematium에서 높고, C. capsici 및 G. cingulata에서 낮았다. 하지만 상처 낸 과실의 예방 효과와 무상처 과실의 치료 효과가 확인된 가용성 황 처리구에서 Colletotrichum 속에 따른 유의한 차이가 없었다.
        4,000원
        51.
        2014.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        균상느타리버섯에서 발생하는 곰팡이 병해 중에서 가장많은 문제를 발생하는 것은 Trichoderma disease 또는green mould 등으로 불리우는 푸른곰팡이병이다.이 병은 Trichoderma, Penicillium, Aspergillus 등의 속(genus)에 포함되는 종들에 의해 발병되는 병을 총칭하는것으로 발생빈도와 피해가 가장 큰 것은 Trichoderma 속의 병원균에 의해 발생하였다. 느타리버섯 균상에 분리된 병원균은 T. longibrachiatum,T. koningii, Trichoderma virens, T atroviride, T. hazianum,T. pseudokoningii 6종이었으며, 발생빈도가 높은 것은 T.virens, T. hazianum, T. longibrachiatum 3종이었고, 각각의 균은 배양적 특성 및 병원성도 각기 다른 특성을 보이고 있었다.T. longibrachiatum 균사생장이 매우 빠르고, 포자형성이 빠르며, 특히 후막포자형성이 잘되는 특성을 있으며,후기에는 진한 녹색으로 변색된다. Trichoderma koningii는 균사생장은 빠르고, 공중균사가 많은 편이며, 포자는공중균사에 밀집되어 형성된다. 특히 Trichoderma virens같은 경우에는 포자형성에 의한 색깔변화가 느리며, 감염후기에 발견되어 그 피해가 심한 편이었다. Trichodermaatroviride. 균사생장은 보통이며, 포자형성은 공중균사에드믈게 형성되며, 후기에는 진녹색을 띤다. 이균의 특징은coconut 냄새와 유사한 향기가 나는 것이다. T. hazianum은 초기에는 균사가 백색으로 매우 빠르고, 공중균사에포자가 형성하며, 후기에는 진한 녹색으로 변색된다. 공중균사에 형성된 포자는 육안적으로 pustules or tufts의 형태를 나타내었다. Trichoderma pseudokoningii 균사생장은 빠르며, 포자형성은 접종부위를 중심으로 형성되며, 후기에는 환무니를 형성하며, 특히 배지 색이 변색되고 후막포자 잘 형성되는 특징이 있었다.
        4,000원
        52.
        2014.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 2013년도에 강원도의 옥수수 재배지들을 조사하고, 밑둥썩음병에 걸린 옥수수로부터 Fusarium균을 분리하였다. 분리한 병원균은 translation elongation factor 1 alpha(EF-1 alpha) 유전자 분석과 형태학적 조사를 통해 확인하였으며, F. subglutinans가 밑둥썩음병의 주요 원인균임을 확인하였다. F. subglutinans KWFS-1의 화학적 방제를 위해, 6개의 살균제와 하나의 살충제를 선발하여 항균효과를 검정하였다. 추천농도로 약제를 사용하였을 때, tebuconazole, difenoconazole, fluquinconazole이 각각 균사생장을 무처리구에 비해 64%, 60%, 55% 억제하는 것으로 나타났다. 반면 에 hymexazol, azoxystrobin, clothianidin, benomyl은 각각 20%, 37%, 35%, 23%를 억제하는 효과를 보였다. 포자생장 억제에서 benomyl, tebuconazole, difenoconazole, fluquinconazole은 포자생장을 완전히 억제하였지만 hymexazol, azoxystrobin, clothianidin이 첨가된 배지에서는 포자생장으로 나타난 균총이 각각 1.1 mm, 2.1 mm, 4.1 mm의 직경크기를 보여 농약별 포자생장 억제효과가 상이함을 보였다.
        4,000원
        53.
        2013.10 구독 인증기관·개인회원 무료
        Apolipophorin III (apoLp-III) is a well-known hemolymph protein having a functional role in lipid transport and immune response of insects. We cloned full-length cDNA encoding putative apoLp-III from larvae of the coleopteran beetle, Tenebrio molitor (TmapoLp-III), by identification of clones corresponding to the partial sequence of TmapoLp-III, subsequently followed with full length sequencing by a clone-by-clone primer walking method. The complete cDNA consists of 890 nucleotides, including an ORF encoding 196 amino acid residues. Excluding a putative signal peptide of the first 20 amino acid residues, the 176-residue mature apoLp-III has a calculated molecular mass of 19,146 Da. Genomic sequence analysis with respect to its cDNA showed that TmapoLp-III was organized into four exons interrupted by three introns. Several immune-related transcription factor binding sites were discovered in the putative 5’-flanking region. BLAST and phylogenetic analysis reveals that TmapoLp-III has high sequence identity (88%) with Tribolium castaneum apoLp-III but shares little sequence homologies (<26%) with other apoLp-IIIs. Homology modeling of Tm apoLp-III shows a bundle of five amphipathic helices, including a short helix 3’. The ‘helix-short helix-helix’ motif was predicted to be implicated in lipid binding interactions, through reversible conformational changes and accommodating the hydrophobic residues to the exterior for stability. Highest level of TmapoLp-III mRNA was detected at late pupal stages, albeit it is expressed in the larval and adult stages at lower levels. The tissue specific expression of the transcripts showed significantly higher numbers in larval fat body and adult integument. In addition, TmapoLp-III mRNA was found to be highly up-regulated in late stages of L. monocytogenes or E. coli challenge. These results indicate that TmapoLp-III may play an important role in innate immune responses against bacterial pathogens in T. molitor.
        54.
        2013.05 구독 인증기관·개인회원 무료
        Mushroom is cultivated as one of the major economical crops in many areas in Korea. The total production has steadily increased from approximately 186,400 M/T in 2007 to 190,111 M/T in 2011. The button mushroom, Agaricus bisporus, showed the 5th production to 13,052 M/T in 2011. Several bacteria are known as the causal agents of diseases of the cultivated button mushroom (Agaricus bisporus) and oyster mushroom (Pleurotus ostreatus). Pseudomonas agarici is the causal agent of browning disease of commercial mushrooms. Colonization of mushroom caps by the bacterium results in development of browning lesions on pileus. These lesions are superficial brown spots and can be round or spreading. But P. agarici never caused sunken lesions and rotting of the mushroom tissues. Antagonists against P. tolaasii, HC42 were selected and their control efficacy of browning disease was investigated in this study. Antagonists against P. agarici, HC42 were selected and their control efficacy of browning disease was investigated in this study. After proceeding antagonistic test, HC42 was selected as a strong antagonist against P. agarici and the HC42 strain was identified as P. safensis with the cultural, physiological and biochemical properties and analysis of the 16S rRNA. The optimal culture medium for the antagonistic bacteria growth was determined as follows: 1.5% D-galactose, 1.5% yest extract, 1% NH4Cl, 1.5% KCl, and 1.0% L-asparagin at pH 6.0 at 25℃. Control efficacy of browning disease by HC42 treatment was 66% on Agaricus bisporus..
        55.
        2012.12 구독 인증기관 무료, 개인회원 유료
        To determine the status of Korean wild reptiles and amphibians infection and relation with climate change of Korean peninsula, references were reviewed. Wild animals serve as intermediate, reservoirs and paratenic hosts to zoonotic parasites of human beings. The parasites and disease can be a serious problem for all herptiles. The infectious diseases, in particular, become parasitized through contact with other reptiles or contaminated objects and environments, or by eating infected food items. Worms are one of the most common intestinal parasites. Among reptiles, the most common infections are flatworms (trematodes), roundworms (nematodes), tapeworms (cestodes), and spiny-headed worms (acanthocephalans). A total of 20 species for infectious diseases from Korean wild reptiles and amphibians has been reviewed. Among them, 11 species was amphibians and 9 species for reptiles. The Korean wild herptiles had total 41 kinds of parasite pathogenic organisms. Meximum infections belonged to Rana nigromaculata as amphibians had 22 kinds of parasite organisms, including Gorgodera aponica, Gorgodera bombinae, Diplodiscus japonicus, Haematoloechus sibiricus japonicus, Pleurogenoides japonicus, Haematoloechus nanchangensis, Haematoloechus variegatus, Haematoloechus lobatus koreanus, Neodiplostomum seoulense, Halipergus japonicus, Haematolechus japonicus, Loxogenes liberum, Baerttia japonica, Ophiotaenia manae, Oswardcruzia lualata, Icosiella kobayashi, Pharyngodon pobypedates, Gyrinicola japonica, Catadiseus sp., Ophisthodiseus sp., Diplorchis sp., and Sparganum. Also, Dinodon rufozonatum as reptiles had 5 kinds of parasite, including Cotylaspis coreensis, Cotylaspis sinensis, Cephalogonimus japonicus, Astiotrema reniferum, Astiotrema odheri, Kaurma orientalis, and Astiotrema sp.. In the future, under the climatic extremes on Korean peninsula such as floods, drought and temperature variability, in particular, the susceptibility of amphibian and reptiles to infection will be increased and they have implications for the emergence of disease and the potential for climate change to exacerbate amphibian decline.
        4,000원
        56.
        2010.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Three-hundred samples of powdered infant formula milk and related products from four different manufacturers in 2010 were collected and surveyed their contaminations for aerobic bacteria, coliform, Enterobacter (Cronobacter) sakazakii, and food-borne pathogens. Fifteen samples of sterilized infant formula milk were all negative on these microorganisms. In all collected products of unsterilized infant formulas and follow-on infant formulas,aerobic bacteria were detected at 239 (83.9%) among 285 samples, and they all were found below 10³ cfu/g. Coliform bacteria were also detected at four among 285 samples. Salmonella spp. and Ent. sakazakii, weren't detected at the all samples. Bacillus cereus was detected at 24 (8.4%) among 285 samples. The level of B. cereus was below 100 cfu/g but it was suitable for the range of specification of B. cereus in infant formulas. Clostridium perfringens, Escherichia coli O157:H7, Staphylococcus aureus and Listeria monocytogenes weren't also detected. In consequence, it was suitable for total viable count, coliform and potential pathogen to the specification of infant formulas and related products.
        4,000원
        57.
        2010.10 구독 인증기관·개인회원 무료
        It is well known that the root-knot nematodes, Meloidogyne spp., incite and aggravate the diseases caused by fungal and bacterial pathogens. The synergistic effects of the inoculation of Meloidogyne incognita combined with Fusarium oxysporum f. sp. lycopersici showed the greatly increased wilt symptoms developed on tomato plants compared to the inoculation of either of the two pests alone. For the biological control of the complex disease, a variety of bacterial isolates were tested for antagonistic effects to select ones that had both nematicidal and antifungal activities. Among forty plant growth-promoting rhizobacteria (PGPR) tested, Paenibacillus polymyxa G508 and G462 and P. lentimorbus G158 showed strong antifungal and nematicidal activities against F. oxysporum f. sp. lycopersici and second-stage juveniles (J2) of M. incognita, respectively, and also inhibited egg hatch of the nematode. The addition of Paenibacillus strains into potted soil suppressed the Fusarium-wilt severity and root galling on tomato and increased plant growths. P. lentimorbus G158 were abundantly proliferated on tomato seeds and hypocotyls more than P. polymyxa G 462 and had no phytotoxic effect on tomato plant. Under the greenhouse conditions, seed treatment of P. lentimorbus G158 reduced wilt severity caused by Fusarium wilt-root knot disease complex and root gall formation and increased tomato growth compared to the untreated control. Root-galls caused by both pathogens treated with bacterial culture had fewer and smaller giant-cells than untreated control, and scanning electron microscopy revealed alteration and distortion of hyphal cell wall of F. oxysporum and lysis of M. incognita egg shell by the bacterial treatment. All of these results suggest the Paenibacillus strains, especially G158 may have a high potential developed as biological control agents for the complex disease.
        58.
        2008.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        청동합금인 우리 전통 식기 놋그릇 유기 소재의 항미생물 특성을 연구하기 위해 주요한 식중독 세균인 Salmonella spp., E. coli O157, E. sakazakii, B. cereus의 배양액을 유기, 구리, 주석, 스테인레스 스틸 쿠폰에 노출 건조 후 생균정도를 분석하였다. 이들 금속표면에서의 살균력 측정결과 Gram(-) 세균인 S. Typhimurium, E. coli와 E. sakazakii는 구리가 가장 높았고 유기, 주석표면, 스테인레스 스틸 금속표면 순으로 항균성이 높은 것으로 나타났다. 그러나 Gram(+)인 B.cereus의 살균효과는 어느 금속표면에서도 살균효과가 거의 나타나지 않았다. S. Typhimurium, E. coli와 E. sakazakii의 구리이온(Cu+2) 최소생육저해 농도는 25 ppm이었지만 B. cereus의 경우는 50 ppm으로 높은 것으로 나타났다. 따라서 구리와는 다르게 강한 경도를 갖고 있는 유기 소재를 식품제조 환경에 적용시킬 경우 Salmonella spp.를 포함한 주요한 Gram(-) 세균의 교차오염을 효과적으로 저감화할 수 있을 것으로 사료된다.
        4,000원
        59.
        2006.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        1995년이후부터 재배되어온 큰느타리버섯은 배양중 오염율 증가, 발이상태불량, 기형버섯의 발생, 수량 격감 등 이른바 연작장해로 불리어지는 재배상 문제점들에 대한 원인파악과 해결책이 요구되어, 전국의 큰느타리버섯 주요 재배농가에서의 종균관리, 배지제조, 배양 및 생육관리 등 전반적인 재배실태와 연작장해 발생정도를 조사한 결과와 균배양, 버섯발생, 자실체 생육과정에서 발생된 병원균을 분리하여 동정한 결과는 다음과 같다. 가. 재배실태조사 결과 재배사 청결관리가 미흡하고 수확 후 재배사 세척 및 소독이 소홀하였다. 나. 발이유기시 습도가 90%이상, 환기는 소량 또는 억제하여 관리한 농가들에서 발이 유기부위에서 세균 및 곰팡이에 의한 오염과 기형버섯 발생 등으로 인해 수량이 낮았다. 다. 자실체 생육시 발이개체수가 과다하였고 환기 및 습도관리 미숙으로 자실체 갈변, 환기장해 등으로 자실체생육이 불량하였다. 라. 강제흡기-강제배기 방식보다 강제흡기-자연배기 방식이나 자연흡기-강제배기 방식의 농가가 많아 발이 유기시 많은 양의 환기를 필요로 하는 큰느타리버섯 재배에 부적합한 환기시스템을 갖추고 있었다. 마. 큰느타리버섯 재배농가에서 수집한 병원균은 총 28점으로 세균13점, 곰팡이15점이었고 채집부위별로는 배양병에서 8점, 발이유기부위에서 12점, 자실체에서 8점을 분리하였다. 바. 큰느타리버섯 재배시 문제가 되는 세균은 Pseudomonas sp. Erwinia sp 가 많았는데. 발이유기 배지표면 오염과 자실체 갈변 및 괴사와 관련된 병징을 유발하였고, 곰팡이는 대부분 Trichoderma sp. 이었으며 주로 배양병 및 발이유기부위에서 발병하였다.
        4,000원
        60.
        2005.09 구독 인증기관 무료, 개인회원 유료
        The purpose of this study was the analysis of sperm ability in Specific Pathogen Free (SPE) miniature pig for production of bio-organ. The collected semen was diluted with extender and stored at 17℃ for up to 7 days. The semen samples were evaluated at 0, 1, 3, 5, and 7 days of storage for analysis of sperm ability. Sperm ability was evaluated by examining viability, progressive motility, sperm abnormality and intensity of the sperm membrane. Also, the semen was processed according to the convenient freezing method, and frozen-thawed sperm was evaluated by examining viability, capacitation and acrosome reaction using chlortetracycline (CTC) staining. Motility of spermatozoa of SPF miniature pig was significantly (P<0.05) lower on 3 days or later compared to the Duroc, Yorkshire and Landrace in domestic boar. The percentage of abnormal spermatozoa of Landrace were significantly (P<0.05) higher than in SPF miniature pig, Duroc and Yorkshire that had a similar percentage on 5 or 7 days of sperm storage. The percentage of spermatozoa with coiled tail decreased during the storage period but there were no significant difference. On the other hand, viability of frozen-thawed spermatozoa had a significantly (P<0.05) lower in SPF miniature pig than in other domestic boars. CTC patterns had no significant difference, but SPF miniature pig had higher percentage of capacitated spermatozoa and lower percentage of acrosome-reacted it than domestic boars. Therefore, this study suggest that it is necessary to develop the suitable extender and freezing methods methods for the high viable rate and fertilizing ability in vitro.
        4,000원
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