• The Plant Pathology Journal
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• 제17권1호
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• pp.45-51
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• 2001

A root rot/vine decline disease occurred naturally on bottle gourd-stocked watermelon, melon, oriental melon and squash grown in greenhouses, but not on these plants grown in fields. Self-rooted watermelon, cucumber, pumpkin and luffa were also proven to be hosts of the pathogen by artificial inoculation in this experiment. The pathogen was identified as Monosporascus cannonballus by comparing microscopic characteristics of fungal structures with those of previously identified fungal strains. Our field investigations showed that the temperature and electric conductivity of soil in infected greenhouses were higher and the soil moisture content was lower than in noninfected greenhouses. To investigate soil-environmental factors affecting disease development, greenhouse trials and inoculation experiments were conducted. The host plants inoculated and grown under conditions of high soil temperature and electrical conductivity ($35\pm2^{\circ}$, 3.2-3.5 mS) and with low soil moisture content (pF 3.0-4.5) were most severely damaged by the fungal disease. Since plants growing in greenhouses ae usually exposed to such environmental conditions, this may be the reason why the monosporascus root rot/vine decline disease has occurred only on cucurbits cultivated in greenhouses but not in field conditions.

• 미생물학회지
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• 제51권3호
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• pp.300-307
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• 2015

좋은 청국장을 발효하는 균주를 선발하기 위하여 청국장 시료로부터 8개의 균주를 선발하였다. 이들 중 7균주는 Bacillus subtilis subsp. subtilis와 99.9% 이상의 가장 높은 16S rRNA 유사도를 보였고, 한 균주는 B. licheniformis와 높은 유사도를 보였다. 선발 균주의 효소 생성을 분석한 결과 모든 균주에서 amylase, cellulase, protease 그리고 lipase 활성을 보였고, 6균주에서 혈전용해능을 보였다. 또한 전통방법으로 제조한 청국장에서 분리한 균주들의 안전성을 확보하고자 분리균주와 계통학적으로 가까운 Bacillus cereus의 독소유전자 7종의 유무를 확인한 결과 모든 선발균주에서 독소유전자 7종을 가지고 있지 않았다. 선발 균주 중 8균주에서 histamine과 tyramine의 생성이 없거나 최소한의 생성을 보였고, HPLC를 이용한 바이오제닉 아민 분해능 분석 결과 대부분의 균주가 tyramine 분해능을 보였다. 선발된 균주로 발효한 청국장의 발효능, 관능, 휘발성염기질소 생성을 확인 하여 7균주가 좋은 품질의 청국장을 만드는 것으로 확인되었고, 이들 선발된 균주로 만든 청국장의 metabolic profile을 분석하였다.

• Mycobiology
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• 제29권1호
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• pp.19-26
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• 2001

Defense mechanisms against anthracnose disease caused by Colletotrichum orbiculare on the leaf surface of cucumber plants after pre-treatment with plant growth promoting rhizobacteria(PGPR), amino salicylic acid(ASA) or C. orbiculare were compared using a fluorescence microscope. Induced systemic resistance was mediated by the pre-inoculation in the root system with PGPR strain Bacillus amylolquefaciens EXTN-1 that showed direct antifungal activity to C. gloeosporioides and C. orbiculare. Also, systemic acquired resistance was triggered by the pre-treatments on the bottom leaves with amino salicylic acid or conidial suspension of C. orbiculare. The protection values on the leaves expressing SAR were higher compared to those expressing ISR. After pre-inoculation with PGPR strains no change of the plants was found in phenotype, while necrosis or hypersensitive reaction(HR) was observed on the leaves of plants pre-treated with ASA or the pathogen. After challenge inoculation, inhibition of fungal growth was observed on the leaves expressing both ISR and SAR. HR was frequently observed at the penetration sites of both resistance-expressing leaves. Appressorium formation was dramatically reduced on the leaves of plants pre-treated with ASA, whereas EXTN-1 did not suppress the appressorium formation. ASA also more strongly inhibited the conidial germination than EXTN-1. Conversely, EXTN-1 significantly increased the frequency of callose formation at the penetration sites, but ASA did not. The defense mechanisms induced by C. orbiculare were similar to those by ASA. Based on these results it is suggested that resistance mechanisms on the leaf surface was different between on the cucumber leaves expressing ISR and SAR, resulting in the different protection values.

• 한국균학회지
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• 제6권1호
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• pp.21-27
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• 1978

The growing behavior of Candida albicans in various concentration of glucose and corticosteroid media was studied with the method of modified hanging slide culture. The strains of Candida albicans used in this study were obtained from vaginal swab from outpatients and were isolated from cultured colonies on Sabouraud's glucose agar media. To detect the budding rate of blastospore, the diluted suspension of Candida albicans in normal saline were inoculated into various concentration of glucose (Gl, G2, G3, G4), corticosteroid (S1, S2, S3, S4) and corticosteroid with 10% pepton broth (D1, D2, D3, D4) respectively and cultured at room temperature $(22{\sim}25^{\circ}C)$. The number of budding of blastospore were counted under the high power field of light microscope (400X) at specific time interval, e.g, 1, 2, 3, 6, 9, 12, 18, and 24 hours after inoculation. The results are as following: 1. The most effective budding rate was seen in G4 media (1.25% glucose) in 18 hours aft inoculation (89%). 2. The budding rate in Sabouraud's glucose broth with various concentration of dexamethasone added, was not significantly different from that of simple Sabouraud's glucose broth within 18 hours after inoculation, but there was statistically. significant difference in two budding rate at 24 hours observation. 3. The budding rate in 10% pepton broth media with various concentration of dexamethasone was almost same budding rate in control group, which is normal saline and 10% pepton broth, except on 2 and 24 hours results.

• 한국초지조사료학회지
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• 제44권1호
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• pp.50-57
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• 2024

Silage inoculants, crucial in modern silage production, comprise beneficial microorganisms, primarily lactic acid bacteria (LAB), strategically applied to forage material during ensiling. This study aimed to compare the effectiveness of various inoculants produced by different companies. Five treatments were evaluated, including a control group: T1 (Lactobacillus plantarum), T2 (Lactobacillus plantarum + Pediococcus pentosaceus), T3 (Lactobacillus plantarum + Pediococcus pentosaceus + Lactobacillus buchneri), T4 (Lactobacillus plantarum + Lactobacillus acidophilus + Lactobacillus bulgaricus), and T5 (Lactobacillus plantarum + Pediococcus pentosaceus + Enterococcus faecium). Italian ryegrass was harvested at the heading stage and treated with these silage inoculants. Samples were collected over a 60-day ensiling period. Co-inoculation with L. plantarum and P. pentosaceus (T2) resulted in significantly higher CP compared to the control group co-inoculation exhibited with resulted in Lactobacillus plantarum and Pediococcus pentosaceus in the T2 treatment exhibited higher CP content of 106.35 g/kg dry matter (DM). The T3 treatment, which included heterofermentative bacterial strains such as Lactobacillus buchneri, exhibited an increase in acetic acid concentration (11.15 g/kg DM). In the T4 treatment group, which utilized a mixed culture of Lactobacillus acidophilus and Lactobacillus bulgaricus, the NH₃-N/TN content was observed to be the lowest (20.52 g/kg DM). The T5 containing Enterococcus faecium had the highest RFV (123) after 60 days. Expanding upon these findings, the study underscores not only the beneficial effects of particular inoculant treatments on silage quality but also underscores the potential of customized inoculation strategies in maximizing nutrient retention and overall silage preservation.

• Journal of Microbiology and Biotechnology
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• 제21권1호
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• pp.55-61
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• 2011

Forty yeast strains isolated from soils taken from different locations in Egypt were tested for their P-solubilizing activities on the basis of analyzing the clear zone around colonies growing on a tricalcium phosphate medium after incubation for 5 days at $25^{\circ}C$, denoted as the solubilization index (SI). Nine isolates that exhibited P-solubilization potential with an SI ranging from 1.19 to 2.76 were genetically characterized as five yeasts belonging to the genus Saccharomyces cerevisiae and four non-Saccharomyces, based on a PCR analysis of the ITS1-26S region amplied by SC1/SC2 species-specific primers. The highest P-solubilization efficiency was demonstrated by isolate PSY- 4, which was identified as Saccharomyces cerevisiae by a sequence analysis of the variable D1/D2 domain of the 26S rDNA. The effects of single and mixed inoculations with yeast PSY-4 and Bacillus polymyxa on the P-uptake and growth of corn were tested in a greenhouse experiment using different levels of a phosphorus chemical fertilizer (50, 100, and 200 kg/ha super phosphate 15.5% $P_2O_5$). The results showed that inoculating the corn with yeast PSY-4 or B. polymyxa caused significant increases in the shoot and root dry weights and P-uptake in the shoots and roots. The P-fertilization level also had a significant influence on the shoot and root dry weights and P-uptake in the shoots and roots when increasing the P-level from 50 up to 200 kg/ha. Dual inoculation with yeast strain PSY-4 and B. polymyxa at a P-fertilization level of 200 kg/ha gave higher values for the shoot and root dry weights and P-uptake in the shoots and roots, yet these increases were nonsignificant when compared with dual inoculation with yeast strain PSY-4 and B. polymyxa at a P-fertilization level of 100 kg/ha. The best increases were obtained from dual inoculation with yeast strain PSY-4 and B. polymyxa at a P-fertilization level of 100 kg/ha, which induced the following percentage increases in the shoot and root dry weights, and P-uptake in the shoots and roots; 16.22%, 46.92%, 10.09%, and 31.07%, respectively, when compared with the uninoculated control (fertilized with 100 kg/ha).

• 한국토양비료학회지
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• 제24권3호
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• pp.219-224
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• 1991

척박(瘠薄)한 야산(野山) 개간지(開墾地)에서의 경제적(經濟的)인 알팔파 초지조성(草地造成)을 목적으로 내산성(耐酸性) R. meliloti "YA03" 근류균제(根瘤菌劑)의 포장접종효과를 검토(檢討)한 결과(結果)는 다음과 같았다. 1. 석회(石灰)와 질소(窒素)를 시용(施用)하지 않은 조건(條件)에서, 시험(試驗) 1년차(年次) YA03의 알팔파 접종(接種)은 대조균주(對照菌株) YA026 및 Rm2011에 비해서 근류중(根瘤重)과 질소고정력(窒素固定力) 및 건초수량(乾草收量)의 증가(增加)를 보였으나, 질소(窒素)를 8kg/10a시용(試用)한 조건(條件)에서는 대체로 Rm2011보다도 저조(低調)한 접종효과를 나타내었다. 2. 석회시용(石灰施用) 없이 질소(窒素)를 8kg/10a 시용(施用)한 조건(條件)에서 YA03 접종구(接種區)의 건초생산은 시험(試驗) 1년차(年次)(276kg/10a)보다 2년차(年次) 잔효(殘效)(479kg/10a)에서 더 높았는데, 이때의 수량(收量)은 근류균(根瘤菌) 무접종(無接種)보다 166%, 대조균주(對照菌株) YA026(399kg/10a) 및 Rm2011(397kg/10a)보다는 20내지 21% 더 증수(增收)되었다. 3. 내산성균주(耐酸性菌株) YA03은 또한, 석회(石灰)없이 질소시용(窒素施用) 2년차(年次) 잔효시험(殘效試驗)에서 대조균주(對照菌株)보다 높은 공중질소(空中窒素) 고정량(固定量)(7.7kg N/10a/Yr.)과 토양내(土壤內) 생균수(生菌數)($1{\times}10^4\;cells/g.\;soil$)를 보여, 산성토양(酸性土壤)에의 적응력(適應力)이 우수(優秀)하였다. 4. 석회시용(石灰施用)과 함께 YA03 접종시(接種時) 시비조건별(施肥條件別) 알팔파의 건초생산은 질소(窒素)+인산(燐酸)+가리(加里)>인산(燐酸)+ 가리(加里)>인산(燐酸)>가리구(加里區) 순(順)으로써 시험후(試驗後) 토양(土壤)의 생균수(生菌數)와 같은 경향(傾向)을 보였다. 5. 척박(瘠薄) 야산지(野山地)에서 내산성균주(內酸性菌株) YA03의 알팔파 접종(接種)에 의한 건초생산은 질소무시용(窒素無施用)보다 시용구(施用區)에서 높았는데, 이 경우(境遇) 석회(石灰)를 병용(竝用)하므로써 약 44% 더 증수(增收)되는 결과(結果)를 보였다.

• 한국식물병리학회지
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• 제1권1호
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• pp.3-11
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• 1985

TMV-OM계통을 접종하여 고온처리시킨 Samsun으로부터 3종의 약독변이계통 Tg 5272, Tw 227 및 Tw 333을 유기시켰다. 이들 약독바이러스는 담배 및 고추에 가벼운 mottling 증상이나 무증징으로 감염되어 TMV-OM에 의한 모자이크, 기형, 위축현상 등을 나타내지 않고 건전식물과 비교하여 생육에 거의 차이를 보이지 않았다. 또한 국부병반기주에 감염되었을 때에도 원주에 비해 전반적으로 미약한 반응을 나타냈고, 특히 Tw 227 및 Tw 333은 N. glutinosa, D. stramonium 및 G. globosa에서 매우 특이한 병징을 나타냈다. 약독바이러스의 물리적 성질 및 TMV-OM 항혈청에 대한 혈청학적 성질의 차는 인정되지 않았다. 한편 약독바이러스를 둔화하였을 때, 약독바이러스의 농도는 TMV-OM에 비해 매우 낮았으나, 이들 바이러스의 자외선흡수 및 전기영동패턴에는 차이를 보이지 않았다.

• 식물병연구
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• 제20권4호
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• pp.270-274
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• 2014

본 연구의 목적은 신갈나무에서 참나무시들음병 병원균인 Raffaelea quercus-mongolicae의 지역별 균주와 기타 Raffaelea 속 근연종의 병원성을 평가하는 것이다. 이 연구에서는 신갈나무에 다양한 균주를 접종한 후, 변재부 내 변색정도로 각 균주의 병원성을 판단하였다. 그 결과 변색부의 평균 측면 확산 정도는 국내에서 분리한 Raffaelea quercus-mongolicae 병원균(8.69 cm)이 일본 병원균(7.51 cm)이나 기타 Raffaelea 속 근연종(3.35 cm)의 평균보다 높았고, 국내 지역별 Raffaelea quercusmongolicae 균주간에는 변색부 측면 확산정도가 4.71-14.90 cm로 병원성의 차이를 보였다. 균주간의 변색부 면적 확산정도는 $1.57-8.42cm^2$로 서로 다른 병원성의 차이를 보였으며, 가장 높은 병원성은 강원도에서 분리한 YY와 전라북도에서 분리한 wj43에서 나타났다.

• 한국버섯학회지
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• 제7권1호
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• pp.1-8
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• 2009

국립원예특작과학원 버섯과에 보존하고 있는 볏짚버섯속(Agrocybe ) 30균주에 대하여 버섯발생 실험을 실시하고, 자실체의 형태적 특성을 조사하였다. 볏짚버섯속 균주중 톱밥배지를 사용한 병재배에서 자실체가 발생된 것은 19균주 이었다. 이중 ASI 19007 등 13균주(I; A. chaxingu )와, ASI 19003 등 5균주(II; A. cylindracea ), ASI 19008(III; Agrocybe sp.)로 그룹 지어졌는데, ASI 19008은 균배양기간, 버섯발생기간 등 재배적 특성과 자실체의 형태적 특징이 다른 2그룹과 차이가 많았다. 또한 재배 계절에 따라 재배적 특성이 다르게 나타났는데 봄, 가을, 겨울에는 ASI 19003 균주가, 여름에는 ASI 19007 균주가 수량이 많고 품질도 좋았다. 따라서 본 연구결과는 계절에 알맞은 품종의 선택을 통하여 볏짚버섯속균의 연중 안정생산이 가능하여 농가소득 증대에 기여할 것으로 본다.