• Journal of Plant Biotechnology
• /
• 제47권2호
• /
• pp.164-171
• /
• 2020

Transgenic Alstroemeria plants resistant to Alstroemeria mosaic virus (AlMV) were generated through RNA-mediated resistance. To this end, the friable embryogenic callus (FEC) of Alstroemeria was induced from the leaf axil tissue and transformed with a DNA fragment containing the coat protein gene and 3'-nontranslated region of AlMV through an improved particle bombardment system. The bar gene was used as a selection marker. More than 300 independent transgenic FEC lines were obtained. Among these, 155 lines resistant to phosphinothricin (PPT) were selected under low stringent conditions. After increasing the stringency of PPT selection, 44 transgenic lines remained, and 710 somatic embryos from these lines germinated and developed into shoots. These transgenic shoots were then transferred to the greenhouse and challenged with AlMV. In total, 25 of the 44 lines showed some degree of resistance. PCR analysis confirmed the presence of the viral sequence. Virus resistance was observed at various levels. Establishment of an efficient transformation system for Alstroemeria will allow inserting transgenes into this plant to confer resistance to viral and fungal pathogens. Accordingly, this is the first report on the production of a transgenic virus-resistant Alstroemeria and lays the foundation for alternative management of viral diseases in this plant.

• Journal of Microbiology and Biotechnology
• /
• 제18권2호
• /
• pp.343-349
• /
• 2008

Vinclozolin, an endocrine disrupting chemical, is a chlorinated fungicide widely used to control fungal diseases. However, its metabolite 3,5-dichloroaniline is more toxic and persistent than the parent vinclozolin. For the biodegradation of vinclozolin, vinclozolin- and/or 3,5-dichloroaniline-degrading bacteria were isolated from pesticide-polluted agriculture soil. Among the isolated bacteria, a Rhodococcus sp. was identified from a 16S rDNA sequence analysis and named Rhodococcus sp. T1-1. The degradation ratios for vinclozolin or 3,5-dichloroaniline in a minimal medium containing vinclozolin $(200{\mu}ml)$ or 3,5-dichloroaniline $(120{\mu}g/ml)$ were 90% and 84.1%, respectively. Moreover, Rhodococcus sp. T1-1 also showed an effective capability to biodegrade dichloroaniline isomers on enrichment cultures in which they were contained. Therefore, these results suggest that Rhodococcus sp. T1-1 can bioremediate vinclozolin as well as 3,5-dichloroaniline.

• Mycobiology
• /
• 제43권1호
• /
• pp.63-70
• /
• 2015

Phytophthora diseases have become a major impediment in the citrus production in Thailand. In this study, an isolate of Phytophthora denominated as PHY02 was proven to be causal pathogen of root rot of Pomelo (Citrus maxima) in Thailand. The isolate PHY02 was morphologically characterized and identified as Phytophthora palmivora based on molecular analysis of an internal transcribed spacer rDNA sequence. This work also presents in vitro evaluations of the capacities of Chaetomium spp. to control the P. palmivora PHY02. As antagonists, Chaetomium globosum CG05, Chaetomium cupreum CC3003, Chaetomium lucknowense CL01 inhibited 50~61% mycelial growth, degraded mycelia and reduced 92~99% sporangial production of P. palmivora PHY02 in bi-culture test after 30 days. Fungal metabolites from Chaetomium spp. were tested against PHY02. Results showed that, methanol extract of C. globosum CG05 expressed strongest inhibitory effects on mycelial growth and sporangium formation of P. palmivora PHY02 with effective dose ED50 values of $26.5{\mu}g/mL$ and $2.3{\mu}g/mL$, respectively. It is interesting that C. lucknowense is reported for the first time as an effective antagonist against a species of Phytophthora.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제39권5호
• /
• pp.246-250
• /
• 2013

Rhinocerebral mucormycosis (RCM) is an opportunistic, potentially life-threatening fungal disease. This infective disease invades not only the facial sinuses, but also the maxilla, zygoma, and rhino-cerebral structures with a massive destruction of the facial skeletons and soft tissue. This disease progresses within various underlying diseases, such as diabetes mellitus, hematologic malignancy, renal failure, and systemic immunodepression. The relationship between mucormycosis and these underlying conditions have been discussed extensively in the literature. The authors studied 6 cases of RCM diagnosed by a tissue biopsy and treated at the department of oral and maxillofacial surgery, from 1997 to 2012. Patients were treated with several kinds of surgical interventions and antifungal agents, and their clinical & radiological signs, underlying conditions, surgical methods, and outcomes were analyzed.

• 한국식물병리학회지
• /
• 제3권4호
• /
• pp.285-290
• /
• 1987

대두 갈색무늬병의 진전은 한 식물체에서 상위엽으로의 진전속도(수직감염율 : vertical progress)과 밀접한 관계가 있다. 실제로 포장에서의 갈색무늬병 진전은 주로 하위엽에서 발병하기 시작하여 상위엽에 비하여 이병정도가 높은 것이 보통이다. 이러한 현상의 원인을 구명하기 위하여 수행한 본 실험에서 갈색무늬병의 감염율은 잎의 성숙도와 정의 상관을 보였으며 이러한 유엽저항성은 접종원의 분포와는 무관한 것으로 보였다. 또 상위엽의 엽표면일출액 (leaf diffusate)은 병원균 포자발아 및 관계신장의 억제 정도가 하위엽의 일출액에 비하여 높았으며 이러한 경향은 저항성품종에서 더욱 현저하여 엽일출액의 어떤 발아억제물질이 갈색무늬병의 유엽저항성에 관여하는 것으로 추정되었다.

• The Plant Pathology Journal
• /
• 제28권1호
• /
• pp.101-106
• /
• 2012

Trifloxystrobin is a strobilurin fungicide, which possesses broad spectrum control against fungal plant diseases. We demonstrated that pre-treating red pepper plants with trifloxystrobin resulted in increased plant growth and leaf chlorophyll content compared with those in control plants. Relative water content of the leaves and the survival rate of intact plants indicated that plants acquired systemic tolerance to drought stress following trifloxystrobin pre-treatment. The recovery rate by rehydration in the drought treated plant was better in those pre-treated with trifloxystrobin than that in water treated plants. Induced drought tolerance activity by trifloxystrobin was sustained for 25 days after initial application. The trifloxystrobin treated red pepper plants also had induced systemic tolerance to other abiotic stresses, such as frost, cold, and high temperature stresses. These findings suggest that applying the chemical fungicide trifloxystrobin induced systemic tolerance to certain abiotic stresses in red pepper plants.

• 한국임상수의학회지
• /
• 제11권1호
• /
• pp.339-341
• /
• 1994

45두의 브로일러 중 2두에서 배양과 직접 현미경 검사에 의해 폐 접합균증이 진단되었다. 폐의 병변부를 Sabouraud 배지에 접종하고 37$^{\circ}C$에서 배양하여 Absidia corymbifera가 분리되었다. 폐조직으로 squash표본을 만들어 직접 현미경 검사를 한 결과 폭이 넓고, 격벽이 없으며, 분지를 나타내는 접합균형 균사를 나타내었다. 감염된 폐조직의 PAS 염색 날인표본에서도 이와 비슷한 균요소가 발견되었다. 닭장의 흙과 닭똥으로부터 고농도의 A. corymbifera가 증명되었는데 이것은 이 브로일러균에서 환경이 감염원이었던 것을 제시하는 것으로 판단된다. 닭의 폐렴 감별진단에 있어서 접합균류도 고려할 것이 강력히 주장되었다.

• Journal of Microbiology and Biotechnology
• /
• 제19권1호
• /
• pp.99-107
• /
• 2009

Strain PUPC1 produces an antifungal protease as well as plant growth promoting enzymes such as 1-aminocyclopropane-1-carboxylate (ACC) deaminase and phosphatase. Morphological, cultural, and physiological characteristics as well as 16S rRNA gene-sequence-based phylogenetic analysis confirmed the taxonomic affiliation of PUPC1 as Chryseobacterium aquaticum. The optimum growth of PUPC1 was observed at pH 6.0 and $30^{\circ}C$, and maximum protease production was observed in medium B amended with 1% tryptone, 0.5% sucrose, and 0.005% $MnCl_2$. The protease was purified by ammonium sulfate precipitation, Sephadex G-75 gel filtration chromatography, and electroelution from preparative SDS-PAGE. The protease had a molecular mass of 18.5 kDa. The optimum pH and temperature stability of the protease were pH 5.0-10.0 and temperature $40-70^{\circ}C$. Chryseobacterium aquaticum PUPC1 and its protease showed a broad-spectrum antifungal activity against phytopathogenic fungi. Strain PUPC1 also exhibited plant growth promoting traits. The objective of the present investigation was to isolate a strain for agricultural application for plant growth promotion and biocontrol of fungal diseases.

• The Plant Pathology Journal
• /
• 제31권1호
• /
• pp.1-11
• /
• 2015

Antimicrobial cyclic peptides derived from microbes bind stably with target sites, have a tolerance to hydrolysis by proteases, and a favorable degradability under field conditions, which make them an attractive proposition for use as agricultural fungicides. Antimicrobial cyclic peptides are classified according to the types of bonds within the ring structure; homodetic, heterodetic, and complex cyclic peptides, which in turn reflect diverse physicochemical features. Most antimicrobial cyclic peptides affect the integrity of the cell envelope. This is achieved through direct interaction with the cell membrane or disturbance of the cell wall and membrane component biosynthesis such as chitin, glucan, and sphingolipid. These are specific and selective targets providing reliable activity and safety for non-target organisms. Synthetic cyclic peptides produced through combinatorial chemistry offer an alternative approach to develop antimicrobials for agricultural uses. Those synthesized so far have been studied for antibacterial activity, however, the recent advancements in powerful technologies now promise to provide novel antimicrobial cyclic peptides that are yet to be discovered from natural resources.

• 식물병연구
• /
• 제20권3호
• /
• pp.189-195
• /
• 2014

Genetic engineering is being used to enhance disease resistance and nutritional value of crops including rice plant. Considering the fast-growing agricultural biotechnology and rapidly increasing global area of transgenic crops, the risk evaluation on environment is necessary. In this study, we surveyed the difference of disease occurrence between transgenic rice variety, Iksan526 transformed with peanut stilbene synthase gene and non-transgenic rice varieties, Dongjin and Nampyeong in the field. Moreover, the possibility of gene transfer from transgenic rice to bacterial and fungal pathogens was investigated. The results of this study indicated that there was no significant difference in the occurrence and severity of the diseases between Iksan526 and Dongjin or Nampyeong. In addition, the results suggested that rice pathogen, such as Xanthomonas oryzae pv. oryzae, Rhizoctonia solani and Magnaporthe grisea did not take up stilbene synthase and bar genes under natural conditions. Moreover the transformed DNA was not transferred to the pathogens even in repetitive contacts.