• The Plant Pathology Journal
• /
• 제35권5호
• /
• pp.417-424
• /
• 2019

Melanose, caused by Diaporthe citri, is one of severe diseases in citrus, a major economic resource in Jeju island. To reduce the usage amount of organic synthetic fungicide, bio-sulfur was tested as an alternative chemical to control citrus melanose in the present study. Direct antifungal activity of bio-sulfur against D. citri was determined through in vitro experiment using artificial nutrient media. Disease severity of melanose on bio-sulfur pretreated citrus leaves was lower than that on untreated ones. To illustrate the mechanism of disease suppression by bio-sulfur, infection structures were observed with a fluorescent microscope and a scanning electron microscope. In fluorescent microscopic observation, most conidia rarely germinated. In addition, hyphal growth on leaves pretreated with bio-sulfur was inhibited compared to that on untreated ones. In scanning electron microscope images of bio-sulfur pretreated leaves, surfaces of most conidia were shrunk while hyphae were morphologically changed and frequently branched. Such microscopic observations were also found for leaves pretreated with a commercial fungicide Dithianon. These results suggest that bio-sulfur may be used to control citrus melanose as an environment friendly alternative to organic synthetic fungicides

• 한국약용작물학회:학술대회논문집
• /
• 한국약용작물학회 2008년도 추계학술발표회
• /
• pp.491-492
• /
• 2008

• 신재생에너지
• /
• 제16권1호
• /
• pp.68-76
• /
• 2020

Operational testing of the THIOPAQ^® facility that removes H₂S from landfill gas was performed for 746 days. The average H₂S removal efficiency was 99.4%, and the input quantities of air, NaOH, and nutrients per sulfur load were 13.1 ㎥/ton, 1.5 ㎥/ton, and 28.7 L/ton, respectively. The purity of the bio-sulfur produced from the facility was 94.8%, with 3.3% impurities, except for moisture. X-ray photoelectron spectroscopy showed that the compositional contents of amino acids and free amino acids of the bio-sulfur surface were 5,308 and 728 mg/kg, respectively. The mean particle size was 3.41 ㎛, which was much smaller than that of chemical sulfur. Based on these results, a high H₂S removal rate of more than 97% is feasible, and high value-added bio-sulfur, which is used as a fungicide because of its hydrophilic characteristics and small size, can be obtained at this facility.

• 농약과학회지
• /
• 제9권2호
• /
• pp.132-139
• /
• 2005

천연 살균활성 물질인 strobilurin으로부터 유래된 ${\beta}$-methoxyacrylate 계열 화합물들은 천연물 자체보다 높은 살균활성 및 안정성을 보이는 것으로 알려졌으며 실제로 다수의 화합물이 우수한 농업용 살균제로 개발 시판되어 지고 있다. 본 연구에서는 보다 나은 살균제를 개발하기 위한 일환으로 티오엔을 곁가지를 가진 새로운 ${\beta}$-methoxyacrylate 계열 화합물을 고안하고 합성하였으며 이들의 살균활성을 6가지 균주에 대하여 in vivo 활성검색을 수행하였다. 새로이 합성된 화합물들은 선택적으로 벼도열병균 및 밀녹병균에 대하여 우수한 살균활성을 보였으며 특히 1b, 1c, 1g 화합물은 100 ppm 농도에서 벼도열병균과 밀녹병균에 대하여 100% 살균효과를 보였다.

• Mycobiology
• /
• 제47권3호
• /
• pp.308-318
• /
• 2019

Bio-sulfur can be produced in the process of desulfurization from a landfill and collected by some microorganism such as Thiobacillus sp. as a sulfur element. In order to investigate practical use of bio-sulfur as an agent for controlling plant disease, in vitro antifungal activity of bio-sulfur was tested against Colletotrichum orbiculare known to cause cucumber anthracnose. Efficacy of bio-sulfur for suppressing anthracnose disease was also evaluated in vivo using cucumber leaves. Mycelial growth of C. orbiculare on medium containing bio-sulfur was inhibited. Disease severity of cucumber leaves pre-treated with bio-sulfur was significantly decreased compared to that of untreated ones. To illustrate how bio-sulfur could suppress anthracnose disease, structures of cucumber leaves infected with C. orbiculare were observed under a fluorescent microscope and a scanning electron microscope (SEM). Cucumber leaves pre-treated with bio-sulfur showed a low rate of appressorium formation whereas untreated ones showed abundant appressoria. Shrunk fungal hyphae were mostly observed on bio-sulfur-pretreated leaves by SEM. Similar results were observed on leaves pre-treated with a commercial fungicide Benomyl(R). These results suggest that inhibition of appressorium formation of C. orbiculare by bio-sulfur may contribute to its suppression of cucumber anthracnose.

• 한국입자에어로졸학회지
• /
• 제13권1호
• /
• pp.25-31
• /
• 2017

This paper offer the characteristics for the detection and classification of biological and non-biological aerosol particles in the air by using laser-induced-fluorescence (LIF) based Bio-aerosol Detection System (BDS). The BDS is mainly consist of an optical chamber, in-outlet nozzle system, 405 nm diode laser, an avalanche photo detector (APD) for scattering signal and photomultiplier tubes (PMT) for fluorescence signals in two different wavelength range ; F1, 510-600 nm and F2, 435-470 nm. The detection characteristics, especially ratio of fluorescence signal intensity were examined using well-known components : polystylene latex (PSL), fluorescence PSL, $2{\mu}m$ of SiO2 micro sphere, dried yeast, NADH, ovalbumin, fungicide powder and standard dust. The results indicated that the 405 nm diode laser-based LIF instrument can be a useful bio-aerosol detection system for unexpected biological threaten alter in real-time to apply for dual-use technology in military and civilian fields.

• Journal of Microbiology and Biotechnology
• /
• 제17권9호
• /
• pp.1568-1572
• /
• 2007

To develop a natural fungicide against Botrytis cinerea and Colletotrichum gloeosporioides, a total of 25 essential oils were tested for their fumigant activity against post-harvest pathogens. The vaporous phases of oils were treated to each fungus on potato dextrose agar medium in half-plate separated Petri plates at $10\;{\mu}g$ per plate. The essential oil of Illicium verum strongly inhibited the mycelial growth of both B. cinerea and C. gloeosporioides by over 90%. On the other hand, the essential oil of Schizonepeta tenuifolia showed inhibitory activity against mycelial growth of only B. cinerea by over 90%. Gas chromatography-mass spectrometry and bioassay indicated trans-anethole in I. verum and menthone in S. tenuifolia as a major antifungal constituent. The essential oils of I. verum and S. tenuifolia and their major constituents could be used to manage post-harvest diseases caused by B. cinerea and C. gloeosporioides.

• 농약과학회지
• /
• 제13권3호
• /
• pp.171-176
• /
• 2009

2008년 5~6월 사이 상주 지역 감 과수원으로부터 분리한 탄저병균(Colletotrichum gloeosporioides)의 prochloraz manganese complex, tebuconazole, mancozeb+myclobutanil, fluquinconazole+prochloraz, tebuconazole+toIyfluanid 등 총 5종의 살균제에 대한 반응을 조사하였다. 분리한 탄저병균 110균주 중 prochloraz ($250\;{\mu}g/m{\ell}$)과 tebuconazole($125{\mu}g/m{\ell}$)에 대하여 각각 97.3%와 98.2%의 균주가 91%이상의 균사생육이 억제되는 것으로 나타났다. Mancozeb + myclobutanil, fluquinconazole + prochloraz 및 tebuconazole + tolyfluanid 스테롤 생합성 저해제와 다른 약제의 합제에 대하여 91% 이상의 균사생육이 억제되는 균주의 비율은 각각 96.4, 99.1 및 96.4%로 나타났다. 공시한 약제 중 감수성이 가장 높은 약제는 fluquinconazole + prochloraz로 나타났다. Tebuconazole과 tebuconazole + tolyfluanid 약제간 r=0.85으로 약제간 교차 저항성의 위험성이 높은 것으로 나타났다.

• The Plant Pathology Journal
• /
• 제27권1호
• /
• pp.59-67
• /
• 2011

A bacterial strain CH-67 which exhibits antagonism towards several plant pathogenic fungi such as Botrytis cinerea, Fulvia fulva, Rhizoctonia solani, Sclerotinia sclerotiorum, Colletotrichum sp. and Phytophthora sp. was isolated from forest soil by a chitin-baiting method. This strain was identified as Burkholderia cepacia complex (Bcc) and belonging to genomovar IX (Burkholderia pyrrocinia) by colony morphology, biochemical traits and molecular method like 16S rRNA and recA gene analysis. This strain was used to develop a bio-fungicide for the control of tomato leaf mold caused by Fulvia fulva. Various formulations of B. pyrrocinia CH-67 were prepared using fermentation cultures of the bacterium in rice oil medium. The result of pot experiments led to selection of the wettable powder formulation CH67-C containing modified starch as the best formulation for the control of tomato leaf mold. CH67-C, at 100-fold dilution, showed a control value of 85% against tomato leaf mold. Its disease control efficacy was not significantly different from that of the chemical fungicide triflumidazole. B. pyrrocinia CH-67 was also effective in controlling damping-off caused by Rhizoctonia solani PY-1 in crisphead lettuce and tomato plants. CH67-C formulation was recognized as a cell-free formulation since B. pyrrocinia CH-67 was all lethal during formulation process. This study provides an effective biocontrol formulation of biofungicide using B. pyrrocinia CH-67 to control tomato leaf mold and damping-off crisphead lettuce and tomato.

• 생물환경조절학회지
• /
• 제31권4호
• /
• pp.376-383
• /
• 2022

이번 연구는 토마토잎곰팡이병 및 점무늬병에 대한 방제력을 개발하고, 온도와 잎의 결로시간에 따른 발생정도를 평가하기 위해 수행되었습니다. 첫 번째 병발생 예측 실험에서는 토마토묘에 Fulvia fulva, Stemphylium lycopersici 분생포자를 각각 1 × 10⁴ conidia·mL^-1로 접종시키고 10-25℃(F. fulva) 및 10-30℃(S. lycopersici)에서 0-18시간 동안 이슬생육상에 두었다. 살균제를 이용한 방제 연구에서는 잎곰팡이병 방제를 위하여 트리미다졸, 폴리옥신 B, 이미녹타딘 트리스(Belkut)를 처리하였으며 점무늬병 방제를 위하여서는 에트리디아졸 + 티오파네이트(가지란)과 삼염기 황산구리(세빈나)를 처리하였다. 엽결로시간이 9시간 이상에서 잎곰팡이와 점무니병이 발생하였으며 결로시간이 길어질수록 병발생률이 높았다. 잎곰팡이병의 발생률은 20℃와 15℃에서 더 높았고, 점무늬병은 25℃와 20℃에서 발병률이 증가하였다. 포자 접종 14일 후에 잎곰팡이병 및 점무늬병이 발생하였으며 잠복기는 14-15일로 추정되었다. 잎곰팡이 및 점무늬병 포자가 처리된 식물체에 접종 후 0시간부터 240시까지 살균제 처리를 한 결과 살균제 종류와 상관없이 일찍 약제를 처리한 식물체에서 방제가가 높았으며 150시간이 지난 처리에서는 방제가가 급격히 떨어졌다. 이번연구에서 개발된 병예측모델과 방제력은 토마토의 잎곰팡이병과 점무늬병을 적기에 방제하고 효과적으로 관리하는 데 도움이 될 수 있을 것이다.