• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.129.2-130
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• 2003

Tomato soil pathogens(Phythopthora spp.) analyed high rates in series culture soil and existed in culture parts. To make a diagnosis of Phythopthora sp. and Its concentration, potato slices were manufactured to a round shape(2.5cm) or retangular form(1x4cm). and then, The potato slices dipped into diagnostic reagents with an antibiotic substance for 2∼4hours. Potato slices treated with a few reagents varied into 15cm depths in innoculated soils for 24hrs. Mycelium of the Phytophthora root rot fungus, Phythopthora capsici, were produced easily on potato slice. We collected many potato slice samples on diseased fields in various area. After storage of 24hrs in 20$^{\circ}C$ incubator, White mycelium of Phythopthora sp. formed on potato slice surface. Dilute concentrations of Phythopthora sp. was detected very low contents(1${\times}$10$^1$sporangia/g). But expressing Phythopthora root rots on potato slice did not developed larger lesions upon storage time in room temperature. These results suggest that the use of potato slice in a series of soil cultural system may still serve as efficient means of diagnosis of Phythopthora root rots in the absence of control measures.

• Journal of Plant Biology
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• 제32권2호
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• pp.67-78
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• 1989

Hybridization of DNA isolated from leaves of Russet Burbank potato with tomato cDNA as a probe revealed the presence of about ten inhibitor 1 genes in the genome. Screening of a genomic library of Russet Burbank potato resulted in isolation of seven different genomic clones carrying inhibitor I genes. One of the genomic clones, clone 2, contained two EcoRI fragments of 3.4 and 1.8 kb in size, respectively, which were hybridized with the probe. The nucleotide sequence of parts of the hybridizing EcoRI fragments revealed that they contain a complete gene which codes for an open reading frame of 107 amino acids. It is interrupted by two intervening sequences of 502 and 493 bp, situated at the positions of codons 17 and 43, respectively, of the open reading frame. Putative regulatory sequences, TATAAA and CCACT, were found at the 5' flanking region. In addition, a copy of a 100 bp repeat found at a tomato inhibitor I gene was identified.

• Journal of Plant Biology
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• 제39권2호
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• pp.93-98
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• 1996

In order to enhance the system of potato transformation and further regeneration, potato was transformed using the Agrobacterium tumefaciens harboring $\beta$-glucuronidase (GUS) gene. We found that a series fo modified medium ttained 100% shoot regeneration within 5 weeks after the preincubated explants on stage I medium were infected with Agrobacterium. Callus appeared at the cut edges of stem segments on stage II medium, mainly at the basal parts. Some explants started to form shoots after two to three weeks on stage III medium containing kanamycin (50 mg/L). When transferred to MS medium containing 200 mg/L kanamycin, 81% of the transformed shoots formed roots at the cut edge of the plantlets. In contrast, untrasformed shoots never rooted and became yellowish after few weeks under the same conditions. Southern and northern analysis indicated in vitro shoot regeneration on the callus derived from the potato explants, which were incubated with Agrobacteria. The regeneration cycle was shortened after the transformatin and finally the transformation efficiency was highly enhanced.

• The Plant Pathology Journal
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• 제23권1호
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• pp.31-33
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• 2007

Phytophthora rot on broad bean(Vicia faba) occurred in the experimental field at Gyeongsangnam-do Agricultural Research and Extension Services from 2004 to 2006. The fungus isolated from the diseased plants grew well on potato dextrose agar and showed an arachnoid or rosaceous colony pattern. Sporangia were conspicuously papillated, noncaducous, ovoid to globose, and $25-64{\times}18-44{\mu}m$ in size. Oogonia and oospores were spherical and measured as 20-32 ${\mu}m$ and 16-28 ${\mu}m$ in size, respectively. Oospores were relatively small and aplerotic. Antheridia were amphigynous, spherical, and unicellula. Chlamydospores were globose and 18-40 ${\mu}m$ in size. Optimum temperature for growth was about $28^{\circ}C$ on potato dextrose agar. The disease occurred in all parts of the plant including roots, stems, leaves and pods in the field. The symptoms similar to those of naturally infected plants were induced by artificial inoculation and the pathogen was re-isolated from the plant. On the basis of mycological and pathological characteristics, the causal pathogen of broad bean rot was identified as Phytophthora nicotianae. This is the first report of Phytophthora rot of broad bean caused by P. nicotianae in Korea.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.135.1-135
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• 2003

A technique for detection of Xanthomonas axonopodis pv. citri, a causal bacterium of canker on Unshiu orange fruits, was developed using bacteriophage. Procedure for the detection was designed on the basis of the previous reports that one group(CPI) of X. axonopodis pv. citri bacteriophage and corresponding two Iysotypes distributed in Korea. First, fruit surface was washed with sterile distilled water and pellet was obtained from centrifugation. The pellet was resuspended in Wakimoto's potato semi-synthetic broth medium and divided equally into two parts. One part was heated in boiling water to kill bacterial cells. Bacteriophages(CP$_1$) were respectively added into two parts and 0.1 ml from each part was mixed with soft agar medium. After incubation for 18 hrs at 25$^{\circ}C$, the causal bacterium of canker was determined based on plaques formed on the medium. This procedure can be effectively used for detection of living bacterial pathogen on fruit surfaces of Unshiu orange.

• The Plant Pathology Journal
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• 제28권2호
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• pp.123-136
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• 2012

Diseases caused by begomoviruses (family Geminiviridae, genus Begomovirus) constitute a serious constraint to tropical and sub-tropical agro-ecosystems worldwide. In recent years, they have also introduced in temperate regions of the world where they have great impact and are posing a serious threat to a variety of greenhouse crops. Begomoviral diseases can in extreme cases reduce yields to zero leading to catastrophic losses in agriculture. They are still evolving and pose a serious threat to sustainable agriculture across the world, particularly in tropics and sub-tropics. Till recently, there have been no records on the occurrence of begomoviral disease in South Korea, however, the etiology of other plant viral diseases are known since last century. The first begomovirus infected sample was collected from sweet potato plant in 2003 and since then there has been gradual increase in the begomoviral epidemics specially in tomato and sweet potato crops. So far, 48 begomovirus sequences originating from various plant species have been submitted in public sequence data base from different parts of the country. The rapid emergence of begomoviral epidemics might be with some of the factors like evolution of new variants of the viruses, appearance of efficient vectors, changing cropping systems, introduction of susceptible plant varieties, increase in global trade in agricultural products, intercontinental transportation networks, and changes in global climatic conditions. Another concern might be the emergence of a begomovirus complex and satellite DNA molecules. Thorough understanding of the pathosystems is needed for the designing of effective managements. Efforts should also be made towards the integration of the resistant genes for the development of transgenic plants specially tomato and sweet potato as they have been found to be widely infected in South Korea. There should be efficient surveillance for emergence or incursions of other begomoviruses and biotypes of whitefly. This review discusses the general characteristics of begomoviruses, transmission by their vector B. tabaci with an especial emphasis on the occurrence and distribution of begomoviruses in South Korea, and control measures that must be addressed in order to develop more sustainable management strategies.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2005년도 BIOINFO 2005
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• pp.151-155
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• 2005

Recently, systems biology has been increasingly applied to gain insights into the complexity of living organisms. Many inaccessible biological information and hidden evidences fur example flux distribution of the metabolites are simply revealed by investigation of artificial cell behaviors. Most bio-models are models of single cell organisms that cannot handle the multi-cellular organisms like plants. Herein, a structured and multi-cellular model of potato was developed to comprehend the root starch biosynthesis. On the basis of simplest plant cell biology, a potato structured model on the platform of Berkley Madonna was divided into three parts: photosynthetic (leaf), non-photosynthetic (tuber) and transportation (phloem) cells. The model of starch biosynthesis begins with the fixation of CO$_2$ from atmosphere to the Calvin cycle. Passing through a series of reactions, triose phosphate from Calvin cycle is converted to sucrose which is transported to sink cells and is eventually formed the amylose and amylopectin (starch constituents). After validating the model with data from a number of literatures, the results show that the structured model is a good representative of the studied system. The result of triose phosphate (DHAP and GAP) elevation due to lessening the aldolase activity is an illustration of the validation. Furthermore, the representative model was used to gain more understanding of starch production process such as the effect of CO$_2$ uptake on qualitative and quantitative aspects of starch biosynthesis.

• The Plant Pathology Journal
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• 제15권5호
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• pp.308-310
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• 1999

A fungus associated with gray blight on tea plant (Camellia sinensis) was identifed as Pestalotiopsis theae based on the mycological characteristics. Mycelial growth on potato dextrose agar and size and shape of conidia of P. theae were similar to those of P. longiseta, but P. theae was different from P. longiseta in the color of three median cells and the number of apical appendages. Artificial inoculation of conidial suspension or mycelial mats on the wounded leaves and shoots of healthy plants induced the same disease, respectively. The Korean native variety was relatively. The Korean native variety was relatively more resistat to P. theae than a Japanese variety‘Yabukita’which has bee recently introduced and planted in large areas of southern parts of Korea. Here, we report the report the first record of gary blight caused by P. theae on tea plant in Korea.

• Journal of Radiation Protection and Research
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• 제33권3호
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• pp.105-112
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• 2008

감자의 재배기간 중에 침적된 방사성 핵종의 토양-작물체 전이계수($TF_a,\;m^2\;kg^{-1}$-fresh)를 측정하기 위하여 감자의 파종 2일전 및 생육 중 세 차례에 걸쳐 $^{54}Mn,\;^{60}Co,\;^{85}Sr,\;^{137}Cs$ 함유 용액을 재배상자의 토양표면에 처리하였다. 파종 전 처리에서는 핵종이 표토(pH 5.2의 양질사토)와 혼합되었다. 조사 부위는 잎, 줄기, 괴경껍질, 괴경육이었다. 파종 전 처리시 $^{54}Mn,\;^{60}Co,\;^{85}Sr,\;^{137}Cs$의 $TF_a$ 값은 작물체 부위에 따라 각각 $1.9{\times}10^{-4}{\sim}1.5{\times}10^{-2}$, $1.8{\times}10^{-4}{\sim}7.5{\times}10^{-4}$, $4.0{\times}10^{-4}{\sim}1.6{\times}10^{-2}$, $1.5{\times}10^{-4}{\sim}3.9{\times}10^{-4}$의 변이를 보였다. 생육 중 처리시 $TF_a$ 값은 파종 전 처리에 비해 대체로 수 배 정도 낮았다. $^{54}Mn,\;^{85}Sr,\;^{137}Cs$의 경우 생육초기 또는 중기 처리시 후기 처리보다 높았으나 $^{60}Co$의 경우 이와 반대였다. 부위 간에는 대체로 잎에서 가장 높았고 괴경육에서 가장 낮았다. 토양으로부터 네 부위로의 총 흡수율은 $0.05{\sim}3.16%$의 범위였다. 파종 전 처리 후 3년차 $^{54}Mn,\;^{60}Co,\;^{137}Cs$의 $TF_a$ 값은 부위에 따라 각각 1년차의 $11{\sim}25%$, $21{\sim}25%$, $38{\sim}67%$였다. 본 연구결과는 감자의 생육 중 방사성 핵종의 단기침적시 영향을 예측하거나 관련 모델의 검증에 활용할 수 있다.

• Journal of Ginseng Research
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• 제4권2호
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• pp.186-193
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• 1980

The causal organism of Phytophthora disease on Panax ginseng Meyer in Korea was isolated and identified as Phytophthora cactorum. It's pathogenicity, etiology, and possible control measures were investigated. Disease symptoms on various parts of ginseng plants were also described The fungus caused seedling and mature plant blight and root rot. Oospores were easily formed on potato dextrose agar and corn meal agar. Oospores, however, were not formed in the diseased root tissues but did in the in footed shoots such as leaves, petioles, and stems and in the inoculated berries.