• Journal of Microbiology and Biotechnology
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• 제15권2호
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• pp.227-233
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• 2005

Fungal strain CGF was isolated from the soil of ChungNam Province, South Korea. Based on the 28S rDNA sequence analysis and the sequence of the internal transcribed spacer (ITS) region of ribosomal DNA, together with morphological and cultural characteristics, this strain was identified as Aspergillus sclerotiorum and renamed Aspergillus sclerotiorum CGF. This is the first strain of Aspergillus sclerotiorum identified in Korea. When the antifungal activity of A. sclerotiorum CGF was evaluated, among the phytopathogenic fungi, mycelial growth of only Phytophthora species was inhibited. Oermination of P. capsid zoospore was also inhibited. The bioactive compound of A. sclerotiorum CGF was highly thermo- and pH-stable.

• 한국약용작물학회지
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• 제10권3호
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• pp.155-161
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• 2002

본 연구 결과 2000년 지역적으로 재배적 환경이 다른 수원, 안동, 영주의 백출 재배 포장에서 발생한 이병주들과 토양 시료로부터 SS-배지와 Jee-배지를 이용하여 분리된 균들은 백출 역병의 원인균인 P. drechsleri로 확인되었다. 이들 분리균 들은 격막이 없는 다량의 팽윤균사를 형성하며, 10% V8A 배지에 배양한 경우 PDA배지에 배양한 경우보다 빠른 균생장 속도를 보이며 $5^{\circ}C$이하와 $40^{\circ}C$이상에서는 전혀 균 생장이 이루어지지 않았다. 10% V8A 배지에서 균을 배양한 후 멸균수와 함께 균질화한 균사-유주자 현탁액을 접종원으로 하여 다량의 유묘에 접종한 결과 $5.0%{\sim}26.4%$와 $23.5%{\sim}72.2%$로 다양한 병반율과 이병주율이 확인되어 효과적인 병원성 검정이 이루어 졌다. 안동지역의 토양시료로부터 분리된 P-A200073 균주와 수원지역의 이병주 뿌리로부터 분리된 P-9755가 병원성이 높아 각각 $26.4%{\sim}63.2%$와 $25.1%{\sim}72.2%$의 병반율과 이병주율을 보였으나 무처리구의 경우 이병주가 발생하지 않았다. 접종 이병주의 조직으로부터 균 재 분리를 시도한 결과 대부분의 뿌리와 땅 가줄기에서 P. drechsleri가 분리되었으나 병반을 보이는 상위 줄기와 엽 조직으로부터는 균이 분리되지 않았다.

• 유기물자원화
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• 제24권4호
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• pp.85-94
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• 2016

본 연구의 목적은 기능성 커피박 퇴비를 개발하고자 커피박과 커피박 퇴비의 특성을 분석하였다. 커피전문점의 커피박 pH, EC, Zn 함량이 상업용 커피박보다 높게 나타났으나 $K_2O$, CaO, MgO, $Na_2O$, Mn 함량은 유의적인 차이가 없었다. 주요 식물병원균 6종(Rhizoctonia solani, Sclerotinia sclerotiorum, Fusarium oxysporum, Phytophthora capsici, Alternaria alternata, and Botrytis cinerea)에 대한 커피전문점과 상업용 커피박 퇴비의 수용성 추출물의 항균활성을 검정한 결과, 공시한 6종의 식물병원균에 대한 항균력이 있음을 확인하였다. 커피박 추출물의 A. altanata 포자발아 억제 및 P. capsici 유주자낭 형성 억제효과를 조사 한 결과, 10% 깻묵+커피박 퇴비 수용성 추출물이 A. altanata의 분생포자 발아관의 신장과 P. capsici의 유주자낭 형성을 유의적으로 억제하였다. 커피박 퇴비의 기능성을 조사하고자 커피박을 90일간 부숙시키면서 30일 간격으로 총 폴리페놀 함량을 조사한 결과, 총 폴리페놀 함량은 부숙시간의 경과에 따라 증가하였으며, 10% 깻묵+커피박 퇴비에서 90일째에 가장 높은 총 페놀 함량인 평균 $0.35{\pm}0.03mg\;GAE/g$로 나타냈다.

• 한국패류학회지
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• 제28권1호
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• pp.65-71
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• 2012

Perkinsus spp.는 국내를 비롯한 전 세계에 걸쳐 수산업적으로 중요한 이매패류에 감염되어 대량폐사를 유발하는 대표적 기생충이다. 본 연구에서는 바지락에서 검출되는 P. olseni의 유주자를 광학현미경과 주사전자현미경을 이용해 미세구조를 관찰한 결과 P. olseni의 유주자는 타원형의 몸체에 1개의 장편모와 1개의 단편모로 구성되어 있었으며, 장편모에는 섬모털을 보유하고 있었으며, 섬모털은 편모의 한쪽 면에만 분포하고 있었다. 유주자의 평균 체장은 $3.37{\pm}0.33{\mu}m$, 체폭은 $1.72{\pm}0.22{\mu}m$ 이었으며, 장편모는 $16.34{\pm}1.52{\mu}m$, 단편모는 $8.25{\pm}1.39{\mu}m$으로 측정되었다. 이는 유럽과 미국에서 보고된 Perkinsus spp.와 비교 하였을 때 몸체의 크기는 작지만 편모의 길이는 긴 것으로 확인되었다.

• 한국자원식물학회지
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• 제21권4호
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• pp.260-264
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• 2008

고추 형질전환체 $T_1$ 및 $T_2$세대의 유묘에 역병균을 접종한 결과 유주포자 $10^3$개/mL에서 접종 5일후 역병 발병율은 $T_1-1$계통 4.0%, $T_1-2$ 10.0%이었으며, 접종 12일후는 $T_1-1$ 계통 52.0%, $T_1-2$ 계통 64.0%로 대비종인 '금탑'과 '수비초' 100%에 비해 발병율이 떨어져 유주포자 $10^3$개/mL에서는 형질전환체의 저항성 계통선발이 가능하였다. 획득된 역병 저항성 형질전환체를 영양고추시험장의 역병 상습포장에서 재배한 결과 생육, 개화소요일수, 과특성 등은 계통간에 다소 차이가 있었으나, 과실모양은 수비초와 매우 유사하였다. 포장에서의 역병의 발생은 계통간에 차이가 많았으며, $T_2-1-6$ 계통과 $T_2-4-9$ 계통은 시판종인 금탑에 비해 약 30%정도 적었다. 포장에서 선발된 형질전환체는 세대의 진전을 통한 저항성의 고정이 필요한 것으로 판단된다. 이상의 결과로 본 연구에서 확립된 형질전환 시스템으로 고추의 역병저항성 형질전환체의 육성이 가능할 것으로 생각된다.

• Ocean and Polar Research
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• 제40권4호
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• pp.203-212
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• 2018

Zoospore release and germling growth of endophytic Ulvella ramosa were examined under various temperatures (10, 15, 20, $25^{\circ}C$) ${\times}$ irradiances (20, 60, $100{\mu}mol\;photons\;m^{-2}s^{-1}$). Additional growth experiments were performed at different salinities (15, 25, 35, 45 psu) and daylengths (8, 12, 16 h). Growth of host Gracilaria vermiculophylla (Ohmi) Papenfuss was estimated under combinations of temperatures (15, 20, 25, $30^{\circ}C$) and irradiances (20, 60, $100{\mu}mol\;photons\;m^{-2}s^{-1}$). Endophyte effects on the host growth were tested in the two temperatures (20, $30^{\circ}C$) and irradiances (60, $100{\mu}mol\;photons\;m^{-2}s^{-1}$). Zoospore release was maximal at $20^{\circ}C$ and $20{\mu}mol\;photons\;m^{-2}s^{-1}$, and germlings grew best under $20^{\circ}C$ and $60{\mu}mol\;photons\;m^{-2}s^{-1}$. No salinity effect on the growth of endophytes was found but endophyte growth was maximal under the daylength of 12 h. G. vermiculophylla grew better at higher irradiances but no growth differences were found between temperatures of $15-30^{\circ}C$. The growth of host species was significantly inhibited by endophytes under $20^{\circ}C$ and $60{\mu}mol\;photons\;m^{-2}s^{-1}$, but host G. vermiculophylla grew well in the endophyte inactive culture conditions of $30^{\circ}C$ and $100{\mu}mol\;photons\;m^{-2}s^{-1}$. In conclusion, endophyte effects on the production of host G. vermiculophylla could be minimized by controlling cultivation depth and harvest period to inhibit endophyte activity.

• 한국식물병리학회지
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• 제14권4호
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• pp.319-324
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• 1998

Induction of systemic acquired resistance (SAR) against phytophthora blight and pathogenesis-related (PR) protein accumulation by TMV infection in pepper plant (Capsicum annuum cv. Nockwang) were examined to understand the mechanism of the systemic acquired resistance in pepper plant. The zoospore suspension of Phytophthora capsici was inoculated on stem of pepper plant in which TMV-pepper strain had been inoculated on fully expanded upper leaves, and thephytopha blight incidence was examined. Both disease severity and lesion length of phytophthora blight were much smaller in TMV pre-inoculated pepper plant than in uninoculated control plants. The phytophthora blight incidence was decreased about 50% in the TMV pre-inoculated pepper, compared to the uninoculated control plant at 10 days after P. capsici inoculation. Accumulation of PR1 and PR5 proteins in intercellular fluid of TMV-inoculated and uninoculated upper leaves were monitored by immuno-blot with tobacco P1b and PR5a, antibody during induction of SAR. PR1 and PR5 were detected from 24 hours after TMV inoculation in both TMV-inoculated and uninouclated upper leaves, and increased rapidly in TMV-inoculation in uninoculated upper leaves were defoliated. PR5 could be detected upto 20 days after TMV inoculation in uninoculated upper leaves. These results suggest that TMV infection induces SAR against phytophthora blight in pepper plant, and that PR proteins are accumulated very rapidly during induction of SAR and maintained for quite long time in pepper plant.

• 한국수산과학회지
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• 제42권5호
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• pp.523-526
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• 2009

Biodegradable polybutylene succinate (BPS) multifilament were designed to degrade upon disposal by the action of afforestration of Ecklonia cava. Matured thalli of E. cava were collected at Jeju for zoospore collection and the substrate for zoospores were BPS multifilament (12 mm, 500 Td/96). The materials were made as nets of $1\;m^2$ with a cross stripes of 10 cm. The unit biodegradable nets bearing germlings of E. cava was moved into Wando where the place is conducting intensive seaweed cultivation in Korea for 5 months of nursery culture until they grew to 10 cm in length after which the nets were transplanted into the sea bed at Jeju at a depth of 12 m and the algal growth was monitored from May 2007 to December 2008. This is the first instance of using the BPS materials for seaweed afforestation to avoid any environmental problems.

• 한국수산과학회지
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• 제43권1호
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• pp.63-68
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• 2010

Ecological characteristics of Undariopsis peterseniana, an endangered brown alga, were investigated from January to December 2007 at Jeju Island, Korea. The U. peterseniana population formed dense patches at depths of 12~17 m depth. Growth in length of the alga reached a maximum of $168{\pm}36cm$ at June. Sorus were observed from May to August, and a maturation peak was detected in June, when bottom seawater temperatures were around $18^{\circ}C$. After zoospore release, the alga bleached and disappeared after August. Developmental initiation of sporophytes occurred at temperature above $15^{\circ}C$, and sorus formation required approximately 236 degree-days. This is the first study to examine a U. peterseniana population throughout the entire year in a natural habitat.

• The Plant Pathology Journal
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• 제35권1호
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• pp.19-31
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• 2019

Bud rot (BR) is the most devastating disease affecting oil palm (Elaeis guineensis) crops in Colombia. Its causal agent, Phytophthora palmivora, initiates the infection in immature oil palm leaflets producing necrotic lesions, followed by colonization of opportunistic necrotrophs, which increases disease damage. To improve the characterization of the disease, we transformed P. palmivora using Agrobacterium tumefaciens-mediated transformation (ATMT) to include the fluorescent proteins CFP-SKL (peroxisomal localization), eGFP and mRFP1 (cytoplasmic localization). The stability of some transformants was confirmed by Southern blot analysis and single zoospore cultures; additionally, virulence and in vitro growth were compared to the wild-type isolate to select transformants with the greatest resemblance to the WT isolate. GFP-tagged P. palmivora was useful to identify all of the infective structures that are commonly formed by hemibiotrophic oomycetes, including apoplastic colonization and haustorium formation. Finally, we detected cell death responses associated with immature oil palm tissues that showed reduced susceptibility to P. palmivora infection, indicating that these tissues could exhibit age-related resistance. The aim of this research is to improve the characterization of the initial disease stages and generate cell biology tools that may be useful for developing methodologies for early identification of oil palm materials resistant or susceptible to BR.