• 한국응용곤충학회지
• /
• 제14권2호
• /
• pp.77-79
• /
• 1975

우리나라에서 Phytophthora capsici균에 의한 가지의 병해는 아직 그 발생이 보고되어 있지 않다. 근래 수원을 포함한 중부지방에 P. capsici균에 의한 피해과가 채집되어 기록병해인 P. parasitica균에 의한 솜털역병과 그 병징, 병원성 및 병원균의 형태등을 비교 검토하였다. 본 병은 9월 강우가 있은 후 발생이 심하였으며 처음 과면에 원형갈색의 병반이 나타나 점차 확대되면서 그 위에 짧은 균계와 분생자경이 밀생하고 유주자양이 풍부히 형성되어 솜털모양으로 공중균계가 길게 자라고 유주자양이 거의 형성되지 않는 솜털병역과는 구별되었다. 그리고 병원균의 형태 및 병원성에 있어서도 뚜렷한 차이를 볼 수 있었다. 따라서 본 병원균은 P. capsica임을 확인할 수 있었으며 미기록인 본병해에 대하여 가지갈색썩음병이라는 이름을 붙이기로 하였다.

• 한국산림과학회지
• /
• 제37권1호
• /
• pp.61-63
• /
• 1978

잣나무털녹병 (Korean white pine blister rust) 이병목(罹病木)의 해부학적(解剖學的) 진단(診斷)을 위(爲)하여, 이병부(罹病部) 수피(樹皮) 혹(或)은 목질부(木質部)의 면도날 절편(切片)을 Chloroform 1 : methanol 2 의 혼합액(混合液)에 24시간(時間) 침지(浸漬)하고, lactophenol cotton blue를 modify 한 액(液)(lactic acid 20gm, phenol crystal 20gm, cotton blue 0.05gm, 60% EtOH 100ml)에 2~5분(分) 염색(染色)하고 60~70% EtOH에 2~3분(分) 씻은 다음 lactophenol로 mount하여 검경(檢鏡)하였다. 기주조직중(寄主組織中)에 분기만연(分技蔓延)한 본병원균(本病原菌) Cronartium ribicola의 비교적(比較的) 넓은 균사(菌絲)와 곤봉상(棍棒狀) 혹(或)은 만곡(彎曲)한 흡기(吸器)가 청염(靑染)됨으로서, 잣나무의 세포조직(細胞組織)과 용이(容易)하게 식별(識別)할 수 있었다. 수피부(樹皮部)에서는 균사(菌絲) 발달(發達)이 양호(良好)하나 목질부(木質部)에서는 방사조치(放射組織)의 투심종단면(透心縱斷面)에서의 관찰(觀察)이 용역(容易)하였고 타(他) 목질부(木質部) 조직(組織)에서는 거의 관찰(觀察)할 수 없었다.

• Weed & Turfgrass Science
• /
• 제2권3호
• /
• pp.306-311
• /
• 2013

Pythium aphanidermatum에 의한 잎마름병(pythium blights)이 chewing fescue "Jamestowm II" 품종에서 2011년 6월 상순에 대구대학교 시험포장에서 발생하였다. 잔디에 발병증상은 잎 끝으로부터 잎마름 증상과 뿌리 썩음증상이 나타나고, 잎색은 진한갈색,회 갈색으로 나타났다. 병원균은 병든 잎과 지제부에서 분리를 하였으며, 동정을 위하여 PDA에서 배양하였다. 균사에는 잎 같은 포자가 복잡한 구조로 부풀어져 있고, 균사로부터 구별되지 않은 실같은 포자낭이 있다. 리보소옴 DNA의 염기서열을 분석한 결과, 유전자은행 DB에 P. aphanidermatum 균주 와의 100% 상동성을 나타낸다는 것을 확인하였다. 병원성은 chewing fescue, creeping bentgrass 및 Kentucky bluegrass에서 코흐의 원칙에 따라 확인하였다. 이것은 chewing fescue 종에서 P. aphanidermatum 에 의한 잎마름병을 국내에서 처음보고 한다.

• The Plant Pathology Journal
• /
• 제29권1호
• /
• pp.52-58
• /
• 2013

Fusarium head blight (FHB) caused by the filamentous fungus Fusarium graminearum is one of the most severe diseases threatening the production of small grains. Infected grains are often contaminated with mycotoxins such as zearalenone and trichothecences. During survey of contamination by FHB in rice grains, we found a bacterial isolate, designated as BN1, antagonistic to F. graminearum. The strain BN1 had branching vegetative hyphae and spores, and its aerial hyphae often had long, straight filaments bearing spores. The 16S rRNA gene of BN1 had 100% sequence identity with those found in several Streptomyces species. Phylogenetic analysis of ITS regions showed that BN1 grouped with S. sampsonii with 77% bootstrap value, suggesting that BN1 was not a known Streptomyces species. In addition, the efficacy of the BN1 strain against F. graminearum strains was tested both in vitro and in vivo. Wheat seedling length was significantly decreased by F. graminearum infection. However, this effect was mitigated when wheat seeds were treated with BN1 spore suspension prior to F. graminearum infection. BN1 also significantly decreased FHB severity when it was sprayed onto wheat heads, whereas BN1 was not effective when wheat heads were point inoculated. These results suggest that spraying of BN1 spores onto wheat heads during the wheat flowering season can be efficient for plant protection. Mechanistic studies on the antagonistic effect of BN1 against F. graminearum remain to be analyzed.

• 한국동물위생학회지
• /
• 제35권1호
• /
• pp.47-52
• /
• 2012

Crocodile farms are getting popular in Bangladesh in an economic point of view. In one of the farms, some crocodiles were found sick and three of them died between May and July in 2006. This investigation was performed to diagnose the cause of the death. Routine postmortem examination was conducted. Samples were collected in 10% neutral buffered formalin for histopathology and in falcon tube for microbiological study. Additional swabs were collected in nutrient broth. Histopathological and microbiological studies were conducted using routine procedures. In addition Giemsa, Gram and PAS stains were performed to detect the organism in tissues. Grossly, esophagus, trachea, lungs, liver, spleen, heart and kidney were congested. Intestine, rectum and colon were hemorrhagic. Clay colored material was found in colo-rectum. Purulent exudates in lungs and thick and cloudy pericardial fluid in pericardial sac were found. Histologically, multifocal granulomatous inflammation was evident in lung, liver, kidney, intestine and colon with bacterial colonies, fungal spores and hyphae. These bacteria were appeared as Gram negative. Fungal hyphae and spores were detected in liver, lungs and colon by using PAS stain. Bacteriologically, E. coli were isolated from lungs exudates, pericardial fluids and intestinal fluids. Therefore, it can be concluded that 3 crocodiles died due to E. coli septicemia concurrent with mycotic infection.

• 대한수의학회지
• /
• 제33권2호
• /
• pp.309-320
• /
• 1993

Guinea pigs were cutaneously inoculated with Trichophyton verrucosum var album, that is a common causative fungus of dermatophytosis in cattle. The developmental process of lesions, clinical and histopathological changes and reisolations of the fungi were studied to evaluate the pathogenicity of Trichophyton verrucosum var album in guinea pigs. Results obtained through the experiments were summarized as follows : 1. The incidence of infection of the clipping group was 13(86%) of 15 animals, and that of the plucking group was 14(93%) of 15 animals. In both of the clipping and plucking groups, visible cutaneoas lesions were developed between 4 and 7 days post inoculation(p.i.). The spreading and the climax stages persisted for 4 to 11 and 6 to 12 days, respectively. 2. In macroscopic observations, formation of various degree of erythemas and scales over the inoculated skin sites were observed in the spreading stage. In the climax stage, exudative changes and dark red crusts were formed as typical circular lesions. In the healing stage, the lesions revealed shedding of crust, alopecia and hair regrowth. 3. In histopathological observations, infiltration of inflammatory cells, hyperplasia, microabscesses and keratinous-hyaloid materials of epidermis were observed in the spreading stage. Hyphal invasion was primarily observed at the level of epidermis and pilosebaceous ducts. In the climax stage, the infected epidermis was thick with severe hyperplasia, hyperkeratosis and acanthosis. The microabscesses with fungal hyphae, folliculitis and hyperplasia of external root sheath were observed in the dermis. The fungal hyphae were observed only in the tissues of hair follicles, that were internal root sheath, cuticle, the keratinized portions of cortex and medulla 4. In reisolation of the inoculated fungus, all trials for ten animals showed positive cultures until 25 days p.i.. Afterward, the reisolation rates were gradually decreased, showing all negative after 40 days p.i..

• 한국어류학회지
• /
• 제27권4호
• /
• pp.306-309
• /
• 2015

본 연구에서는 2014년 넙치 치어를 사용하여 실험하는 과정에서 폐사가 발생하였다. 병어는 외관상 특이한 증상을 보이지 않았으나 아가미에서 많은 양의 균사가 관찰되었다. 기생충과 세균은 병어로부터 분리되지 않았다. 진균에 감염된 넙치와 건강한 넙치를 혼합 사육한 결과, 건강한 넙치는 7일이내에 100% 폐사되었고 폐사어는 아가미에 진균이 심하게 감염되어 있었다. 병리조직학적 검사 결과, 아가미의 새엽, 새판 및 새파 주위에 균사체와 다수의 균사가 관찰되었다. 이상의 연구 결과, 넙치의 폐사는 진균 감염과 연관성이 있을 것으로 사료되었다.

• 한국응용곤충학회지
• /
• 제13권4호
• /
• pp.245-249
• /
• 1974

방사선을 이용한 도열병연구의 기초자료로서 도열병균의 포자와 발아균계에 각각 X-ray 10, 40, 80, 120kR를 조사시켜 그들의 방사선감수성 및 생존율을 조사한 결과는 다음과 같다. 1. 도열병균의 포자발아율은 X-ray 소사선량의 증가에 반비례하여 감소되었으며 120kR에서는 거의 생존하지 못하였다. 2. 비교적 저선량인 10kR 조사에서는 초기발아관신장의 촉진 현상을 보였으며 선량의 증가에 따라 균계의 사멸 현상이 현저하였다. 3. X-ray 조사에 의한 발아균계의 생존율 및 신장은 선량의 증가에 반비례하여 감소하였다. 4. X-ray를 조사받은 발아균계는 포자에 비하여 높은 방사선 감수성을 보였으며, 고선량일수록 그 차이는 현저하였다. 5. X-ray 조사에 의한 도열병균의 돌연변이율은 조사선량에 정비례하여 증가하였다.

• 한국환경농학회지
• /
• 제30권3호
• /
• pp.346-356
• /
• 2011

BACKGROUND: Chemical fungicides not only may pollute the ecosystem but also can be environmentally hazardous, as the chemicals accumulate in soil. Biological control is a frequently-used environment-friendly alternative to chemical pesticides in phytopathogen management. However, the use of microbial products as fungicides has limitations. This study isolated and characterized a three-antifungal-enzyme (chitinase, cellulase, and ${\beta}$-1,3-glucanase)-producing bacterium, and examined the conditions required to optimize the production of the antifungal enzymes. METHOD AND RESULTS: The antifungal enzymes chitinase, cellulase, and ${\beta}$-1,3-glucanase were produced by bacteria isolated from an sawmill in Korea. Based on the 16S ribosomal DNA sequence analysis, the bacterial strain AM50 was identical to Streptomyces sp. And their antifungal activity was optimized when Streptomyces sp. AM50 was grown aerobically in a medium composed of 0.4% chitin, 0.4% starch, 0.2% ammonium sulfate, 0.11% $Na_2HPO_4$, 0.07% $KH_2PO_4$, 0.0001% $MgSO_4$, and 0.0001% $MnSO_4$ at $30^{\circ}C$. A culture broth of Streptomyces sp. AM50 showed antifungal activity towards the hyphae of plant pathogenic fungi, including hyphae swelling and lysis in P. capsici, factors that may contribute to its suppression of plant pathogenic fungi. CONCLUSION(S): This study demonstrated the multiantifungal enzyme production by Streptomyces sp. AM50 for the biological control of major plant pathogens. Further studies will investigate the synergistic effect, to the growth regulations by biogenic amines and antifungal enzyme gene promoter.

• 대한이식학회지
• /
• 제32권4호
• /
• pp.104-107
• /
• 2018

Mucormycosis is an extremely rare but potentially life-threatening fungal infection. Gastrointestinal (GI) mucormycosis is very rare and occurs primarily in highly malnourished patients, especially in infants and children. A 55-year-old man with end-stage renal disease due to diabetic nephropathy, who had undergone deceased donor kidney transplantation 2 years prior, complained of abdominal pain and distension with a 3-day duration. Computed tomography revealed diffuse gastric wall thickening, and a huge amount of grey colored necrotic debris surrounded by erythematous erosive mucosa was observed at the antrum to upper body by GI endoscopy. The microscopic examination obtained from a GI endoscopic specimen demonstrated peptic detritus with numerous non-septate mucor hyphae in the mucosa and submucosa. Mucormycosis was diagnosed based on the clinical findings and morphological features. A total gastrectomy was performed and an antifungal agent was administered. A microscopic examination of the surgical specimen demonstrated invasive mucormycosis with numerous fungal hyphae with invasion into the mucosa to subserosa. The patient and graft were treated successfully by total gastrectomy and antifungal therapy.