• The Korean Journal of Ecology
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• 제15권4호
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• pp.345-354
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• 1992

Allocation patterns of energy and mineral elements were investigated with phaseolus multiflorus grown in the environmental gradients. The result showed different energy allocation patterns according to relative light intensities and nutrients. The optimal switching time of energy allocation from vegetative to resproductive growth was delated as decreasing relative light intensity. The switch of the shift to reproduction was timed earlier in phosphorus treatment and delayed in nitrogen treatment. Analyzing the mineral elements to various organs, patterns of energy allocation were different from those of mineral allocation. There was no significant difference for allocation patterns in relative light intensity gradients. it was shown that n and p were distributed over the reproductive organs, k mainly in stems, ca in leaves and na in roots. mg was evenly distributed in each organs.

• Journal of Plant Biology
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• 제34권3호
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• pp.229-238
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• 1991

The main objective of this study was to clarify the taxonomic status and the speciation mechanism of Viola albida complex in Korea. The complex includes three very closely related taxa, taxonomic ranks of which are much in dispute. These taxa in the complex are sympatric in distribution, and they are very similar in most morphological characteristics. Comparative morphological analyses revealed that they can be distinguished on the basis of leaf shape, although they show complicated patterns of variation in leaf shape. The variation of leaf shape in each taxon appeared to be maintained through developmental process, and extensive cleistogamy and vegetative reproduction in these taxa are suggested as the mechanisms maintaining the variation. Genetic variation in this complex was monomorphic in all 14 loci examined. Palynological study also showed that these taxa have the same pollen morphology. These results strongly suggested that they should be recognized as varieties of V. albida; var, albida, var. chaerophylloides, and var. takahashii. The results also suggested that some individuals that can be assigned to var. takahashii might be hybrids between var. albida and var. chaerophylloides.

• Journal of Plant Biology
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• 제34권1호
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• pp.59-66
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• 1991

홍조 참보라색우무(Symphyocladia latiuscula (Harvey) Yamada)의 형태적 식별형질들을 야외 및 실내배양 재료를 통해 검토하고 생활사를 밝혔다. 본 종은 엽체의 체장이 5-15 cm이고, 정단을 제외한 전 엽체에 피층이 발달하며, 주축과 측지의 유합정도는 5-7 절편에 달한다는 점에서 Symphyocladia속의 다른 종들과 구분된다. 생식기관의 형태와 발달과정은 속내의 다른 종들과 구분된다. 생식기관의 형태와 발달과정은 속내의 다른 종들과 유사하나 소측지의 변형에 의해 장상의 사분포자탁을 형성하는 것이 특징적이다. 본 종은 야외 및 실내배양 재료 모두에서 영양모상엽이 형성되어 S. pennata와 구분되었고, 따라서 지금까지 polysiphonieae족과 Pterosiphonieae족을 구별하기 위한 기본 식별형질로서 인식되어 왔던 영양모상엽의 존재 유무는 부류학적인 의의가 없음을 확인되었다. 실내배양에서 본 종의 Polysiphonia형 생활사를 반복하나 배우체의 체장이 포자체보다 상재적으로 작아 세대간 크기의 차이가 현저한 이형현상이 관찰되었다. 본 종은 한국 전 해안의 조간대 중부 이하의 지역에서 전 계절에 걸쳐 흔히 채집되며, 하계에 배우체의 출현비율이 높았다.

• 미생물학회지
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• 제34권3호
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• pp.75-81
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• 1998

자연계로부터 분리한 효모중에서 새우젓으로부터 분리한 효모균주 504D가 alkaline 조건에서 가장 우수한 proteinase 생산성을 보여 분류동정하였다. 분리효모의 형태학적 특성은 주로 영양세포로 출아증식을 하였으나, citric acid가 함유된 MM 배지에서만 위균사를 형성하였고, N-acetylglucosamin과 ${\beta}$-D-glucose가 첨가된 MM 배지에서만 진균사를 형성하였다. 유성적으로 자낭포자를 형성함으로써 반자낭균류이었고, 무성적으로 출아포자 및 분절 포자를 형성하였다. 생리생화학적인 특성으로 대부분의 탄소원과 nitrate 및 nitrate를 이용하지 못하였으나 일부 유기산과 알콜류를 이용하였다. 세포지방산을 분석한 결과, 불포화지방산 53.67%와 포화지방산 14.58%로 나타났으며, 대조균들에는 관찰되지 않는 C17:1이 관찰되었다. 전체적인 실험결과에서 분리균은 균사형성능과 세포지방산의 조성에서 약간의 차이를 제외하면 대조균 Saccharomycopsis lipolytica KCCM 12495 및 KCCM 35426의 모든 특성들과 거의 동일하여 분리효모 504D를 Yarrowia lipolytica로 동정하였다.

• 한국식품영양과학회지
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• 제7권1호
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• pp.19-23
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• 1978

1. 식물(植物)의 크기에 따라서 저온(低溫)의 날극감응(剌戟感應)을 달리하였다. 2. 유식물시대(幼植物時代)에 있어서 단기간(短期間)의 저온(低溫)의 영양이 추태개화(抽苔開花)를 빠르게 하였다. 3. 저온처리후(低溫處理後)의 추태개화촉진(抽苔開花促進)의 현상(現象)은 성숙식물(成熟植物)보다도 유식물(幼植物)에 있어서 더 크고 특히 발아직전기(發芽直前期)가 가장 현저(顯著)하였다. 4. 저온(低溫)에 처리(處理)한 유식물(幼植物)은 그 묘(苗)가 큰 것일수록 전생장기간(全生長期間)이 점차적으로 길어진 것을 볼 수 있었으나, 처리후(處理後)는 반대(反對)로 단축(短縮)되었다. 5. 유식물(幼植物)에 $4^{\circ}C$내외(內外)의 저온(低溫)으로 처리기간(處理期間) 17일(日) 전후(前後)에서 현저(顯著)한 개화촉진(開花促進)을 나타냈으나 성숙식물(成熟植物)은 40일이하(日以下)에서도 추태(抽苔)하지 않았다.

• Fisheries and Aquatic Sciences
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• 제1권1호
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• pp.147-151
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• 1998

The reproductive phenology of Gracilaria verrucosa was studied in Cheongsapo near Pusan, Korea. Among the life history phases, tetrasporic plants occurred dominantly in varying degrees of abundance throughout the year except from July to September. Cystocarpic plants increased rapidly during summer, and then recorded maximum abundance in July. Whereas, seasonal peaks of spermatangial plants were observed in April and September. However, they were less than cystocarpic plants in abundance. Vegetative plants dominated from December to May for long period, with a occurrence peak in February. Even though fertile plants in both gametophytes and tetrasporophytes occurred throughout the year, their seasonal abundance suggests that the positive correlation between reproduction and water temperature is basically found in the reproductive pattern of Gracilaria verrucosa. The distributional aspect of life history phases appears to be related with differences of their longevity, fecundity or survivorship.

• Applied Microscopy
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• 제46권2호
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• pp.83-88
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• 2016

Structural differentiation of the connective stalk in giant duckweed, Spirodela polyrhiza, was examined to reveal the anatomical and ultrastructural characteristics within reduced shoot. The study focuses primarily on structural features of the connective stalk (CT), which connect offspring to their mother fronds. Photoautotrophic offspring fronds remained connected by stalks to mother fronds in the reproductive pockets until separation. The CT originated from the meristematic region of the abaxial frond and joined the fronds laterally with two abscission layers. The most notable features of the CT were polymorphic mitochondria, random occurrences of fibrillar structures in intercellular spaces, and great variability in cell wall thickness. Vascular tissues in CTs were highly reduced, demonstrating only a central vascular strand. Grana with 2 to 4 thylakoids and starch grains were found in the chloroplasts. A chlorophyll assay indicated high chlorophyll concentrations in daughter fronds and low concentrations in CTs. The frond and CT, while physically connected to each other, functioned independently. Despite great reduction in S. polyrhiza, the CT has proven to be very efficient for separating offspring from the mother frond, which lends to its capacity for rapid vegetative reproduction. The ultrastructural aspects of CTs in S. polyrhiza were characterized for the first time in this study.

• KSBB Journal
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• 제18권6호
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• pp.435-439
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• 2003

형질 전환된 담배 seed에서 담배 식물체를 유도하여 White 액체 배지에서 기관 배양하였다. 암조건, sucrose 2%의 조건에서 좋은 growth pattern을 나타내었고, 계대 배양은 외마디법을 이용하여 2주마다 하였다. 기관 배양에서 hGM-CSF production pattern을 보면, intracellular에서는 큰 변화 없이 약 30 ng/g의 일정한 농도를 나타내었다. Extracellular에서 hGM-CSF 농도는 배양 6일 이후부터 급속하게 증가하기 시작하여 배양 12일째에 약 0.2ng/$m\ell$의 농도를 나타낸다. 기관배양은 다른 식물세포 배양 시스템에 비해 생산되어진 단백질의 안정성이 크다는 장점에 비해 세포 내에서 배지 내로의 단백질 분비가 적다는 단점이 있다. 이를 극복하기 위해 다양한 permeabilizing agents를 투여하여 담배 세포의 permeability를 증가시키고자 하였다. 그 결과, Pluronic F-68과 PEG8000을 첨가한 경우 담배 세포에서 배지 내로의 단백질 분비가 원활해졌음을 확인할 수 있었다.

• 식물분류학회지
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• 제47권1호
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• pp.1-5
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• 2017

The population status of Hydrangea luteovenosa Koidz. in Korea was investigated, with an emphasis on its genetic diversity. From field surveys, we obtained the only locality record for a wild population in Jeju Island, which contained 285 individuals in total. Genotyping was performed using five microsatellite markers for the all extant plants in Korea. Three Japanese populations were also genotyped for the comparative analyses. The genotyping result showed that the Jeju population consisted of only two multilocus genotypes, including identical heterozygous genotypes at two loci; it had been maintained mostly by vegetative reproduction; and although the Jeju population is geographically far from Japanese populations, all alleles observed in the Korean population were shared with Japanese populations, suggesting the possibility that H. luteovenosa in the Jeju Island had been recently migrated or introduced from Japan. Future ecological and genetic studies associated with negative effects of low genetic variation will be essential for determining the conservation direction of the threatened Korean population of this species.

• The Plant Pathology Journal
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• 제27권1호
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• pp.20-25
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• 2011

Gibberella zeae (anamorph: Fusarium graminearum), a homothallic (self-ferile) ascomycete with ubiquitous geographic distribution, causes serious diseases in several cereal crops. Ascospores (sexual spores) produced by this fungal pathogen have been suggested as the main source of primary inoculum in disease development. Here, we report the function of a gene designated GzRUM1, which is essential for ascospore formation in G. zeae. The deduced product of GzRUM1 showed significant similarities to the human retinoblastoma (tumor suppressor) binding protein 2 and a transcriptional repressor, Rum1 in the corn smut fungus (Ustilago maydis). The transcript of GzRUM1 was detected during the both vegetative and sexual stages, but was more highly accumulated during the latter stage. In addition, no GzRUM1 transcript was detected in a G. zeae strain lacking a mating-type gene (MAT1-2), a master regulator for sexual development in G. zeae. Targeted deletion of GzRUM1 caused no dramatic changes in several traits except ascospore formation. The ${\Delta}$GzRUM1 strain produced perithecia (sexual fruit bodies) but not asci nor ascospores within them. This specific defect leading to an arrest in ascospore development suggests that GzRUM1, as Rum1 in U. maydis, functions as a transcriptional regulator during sexual reproduction in G. zeae.