• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1998.06a
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• pp.74-78
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• 1998

경기도 퇴촌에 위치한 경희대학교 연습림내의 낙엽송, 잣나무 및 굴참나무의 천연활엽수로 구성된 3개의 임반에서 경사도와 년간 강우량 변화에 따른 투수특성을 조사하였다. 3개의 임반의 O, A, B층은 3개 임반 모두 경사도가 낮은 하부사면에서 관찰되었으나 경사도가 높은 산사면이나 수간우가 많은 일부 지역에서는 바로 암반층 또는 풍화층이 나타나는 경향을 보이고 있다. 그러나 잣나무 임반은 유기물 퇴적층과 A층이 낙엽송이나 굴참나무 임반보다 잘 발달되어 O층은 약 5내지 10cm 정도이고 A층 또한 O층 아래로 약 50cm까지 깊게 발달되었다. 낙엽송 임반의 하부사면의 경우 A층의 발달이 약 35cm부터 약60cm 에 이르고 있으나 토성을 구성하는 요소중 직경 2mm 이상의 자갈에 토양입자들이 전체 토양의 40%정도를 차지하고 있다. 이러한 토층분화 특성을 달리하는 임반에서의 투수특성은 표층토에서는 약 5.2cm/hr였고 A층에서는 평균 8.2cm/hr 정도였다. 이는 A층에서의 토성이 주로 자갈로 구성되어 대공극을 이루고 있고 평균 부피수분함량이 약 25%인 점을 감안하면 상대 투수속도에 영향을 미치는 것으로 조사되었다. 그리고 산지사면의 상부보다 상대투수속도가 증가되는 경향을 볼 수 있는데 이는 상부에서의 토층발달이 제대로 이루어지지 않아 투수속도에 영향을 주는 것으로 판단된다. 따라서 본 실험의 결과로 추정할 때 지표층에 존재하는 유기물과 토층 분화 정도가 투수에 영향을 미치는 것으로 판단된다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.5
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• pp.386-395
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• 2006

The core questions for determining nitrogen topdress rate (Npi) at panicle initiation stage (PIS) are 'how much nitrogen accumulation during the reproductive stage (PNup) is required for the target rice yield or protein content depending on the growth and nitrogen nutrition status at PIS?' and 'how can we diagnose the growth and nitrogen nutrition status easily at real time basis?'. To address these questions, two years experiments from 2001 to 2002 were done under various rates of basal, tillering, and panicle nitrogen fertilizer by employing a rice cultivar, Hwaseongbyeo. The response of grain yield and milled-rice protein content was quantified in relation to RVIgreen (green ratio vegetation index) and SPAD reading measured around PIS as indirect estimators for growth and nitrogen nutrition status, the regression models were formulated to predict PNup based on the growth and nitrogen nutrition status and Npi at PIS. Grain yield showed quadratic response to PNup, RVIgreen around PIS, and SPAD reading around PIS. The regression models to predict grain yield had a high determination coefficient of above 0.95. PNup for the maximum grain yield was estimated to be 9 to 13.5 kgN/10a within the range of RVIgreen around PIS of this experiment. decreasing with increasing RVIgreen and also to be 10 to 11 kgN/10a regardless of SPAD readings around PIS. At these PNup's the protein content of milled rice was estimated to rise above 9% that might degrade eating quality seriously Milled-rice protein content showed curve-linear increase with the increase of PNup, RVIgreen around PIS, and SPAD reading around PIS. The regression models to predict protein content had a high determination coefficient of above 0.91. PNup to control the milled-rice protein content below 7% was estimated as 6 to 8 kgN/10a within the range of RVIgreen and SPAD reading of this experiment, showing much lower values than those for the maximum grain yield. The recovery of the Npi applied at PIS ranged from 53 to 83%, increasing with the increased growth amount while decreasing with the increasing Npi. The natural nitrogen supply from PIS to harvest ranged from 2.5 to 4 kg/10a, showing quadratic relationship with the shoot dry weight or shoot nitrogen content at PIS. The regression models to estimate PNup was formulated using Npi and anyone of RVIgreen, shoot dry weight, and shoot nitrogen content at PIS as predictor variables. These models showed good fitness with determination coefficients of 0.86 to 0.95 The prescription method based on the above models predicting grain yield, protein content and PNup and its constraints were discussed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.4
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• pp.312-318
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• 2010

This study was carried out to develop and test a prototype program that recommends the nitrogen topdressing rate using the color digital camera image taken from rice field at panicle initiation stage (PIS). This program comprises four models to estimate shoot N content (PNup) by color digital image analysis, shoot N accumulation from PIS to maturity (PHNup), yield, and protein content of rice. The models were formulated using data set from N rate experiments in 2008. PNup was found to be estimated by non-linear regression model using canopy cover and normalized green values calculated from color digital image analysis as predictor variables. PHNup could be predicted by quadratic regression model from PNup and N fertilization rate at panicle initiation stage with $R^2$ of 0.923. Yield and protein content of rice could also be predicted by quadratic regression models using PNup and PHNup as predictor variables with $R^2$ of 0.859 and 0.804, respectively. The performance of the program integrating the above models to recommend N topdressing rate at PIS was field-tested in 2009. N topdressing rate prescribed for the target protein content of 6.0% by the program were lower by about 30% compared to the fixed rate of 30% that is recommended conventionally as the split application rate of N fertilizer at PIS, while rice yield in the plots top-dressed with the prescribed N rate were not different from those of the plots top-dressed with the fixed N rates of 30% and showed a little lower or similar protein content of rice as well. And coefficients of variation in rice yield and quality parameters were reduced substantially by the prescribed N topdressing. These results indicate that the N rate recommendation using the analysis of color digital camera image is promising to be applied for precise management of N fertilization. However, for the universal and practical application the component models of the program are needed to be improved so as to be applicable to the diverse edaphic and climatic condition.

• Applied Microscopy
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• v.31 no.4
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• pp.355-365
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• 2001

This study was performed to investigate the distribution and differentiation on the immunoreacted cells of the ChAT (choline acetyltransferase) at the Meynert basal nucleus of the forebrains in the growth periods of rat, using the immunohistochemistric method. According to the cell shape and the ratio of long axis vs short axis of cell soma, the ChAT antibody reacted nerve cells in the Meynert basal nucleus of the rats were classified into six types. In the adult rats, the FD (frequency distributions) of round, oval and elongated cells were maximum. The FD of these types were shown to be progressively decreased during the postnatal development. In addition, the FD of elongated nerve cells in were observed in the adult rats respectively. This was thought to be the same phenomenon as those in the round and oval cells . The total mean volume of ChAT antibody reacted cell somata was lowest in the PND (postnatal days) 7 rats and was highest in the PND 21 rats. But, those were decreased to the adult. These results suggest that ChAT antibody reacted nerve cells grow up to PND 21 and then, differentiate into the various types by neurites outgrowing. On the electron micrography, the adult rat forebrain cells were obtained to be well developed ribosomes, polysomes , rough endoplasmic reticula and mitochondria. The immunreactivities were observed in ribosomes, polysomes, rough endoplasmic reticula and outer membrane of mitochondria. Golgi complexes were poorly developed and not showed jmmunreactivity. The ribosomes , polysomes and endoplasmic reticula are considered to be closely related to the inter cellular localization and biosynthesis of the ChAT but not Golgi complex. According to the results in the present study, it is considered that the ChAT-immunoreacted nerve cells in the Meynert basal nucleus of the rat forebrains are differentiated throughout the postnatal development with following processes of changes; 1) the cholinergic nerve cells develop postnatally 2) cell soma volumes gradually increase during the early postnatal days 3) and then, cells differentiate into the various types by projecting the neurites to the appropriate area after PND 21.

• Journal of Plant Biotechnology
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• v.41 no.4
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• pp.216-222
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• 2014

This study was carried out to develop an efficient transformation protocol via particle bombardment with PLBs (protocorm-like bodies) in Phalaenopsis. To achieve this aim, osmoticum treatment and an increasing shooting chances in particle bombardment process were applied for this study. In addition, pCAMBIA3301: ORE7 vector which contains a herbicide-resistance bar gene as a selectable marker and ORE7 gene as a gene of interests were employed. With regard to the increasing chances of shooting in particle bombardment, double shooting was the best results with 1.5 ~ 2.5 times higher than those of a single or triple shooting treatment in the productioon of PPT (D-L-phosphinothricin)-resistant PLBs. However, regeneration rate of shoots in double shooting was not high as a single shooting. Further, double shooting showed 35 ~ 40% higher than that of a single shooting in the frequency of browning. Regarding effects of different osmotic treatments, combination of 0.2 M sorbitol with 0.2 M mannitol showed the best results in transformation efficiency, regeneration of transformants and reduction of browning. Putative transgenic Phalaenopsis plants were analyzed by PCR analysis and confirmed the presence of bar and ORE 7 gene. Also, real-time PCR was conducted by using 21 transgenic plants and showed only 4 plants had one copy of transgene; whereas, the other 17 plants had more than 2 copies of transgene. Transgenic phalaenopsis plants produced in this study were transferred to pots and flowered normally without morphological variations in flower and leaf.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.4
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• pp.359-367
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• 1985

This experiment was conducted to study effect of cold water damage on some growth characters related to source and sink at reproductive growth stage in Jinan (sea level 303m). The cold water irrigation duration had irrigated 4, 8 and 12 days at panicle formation stage and reproduction division stage compared to perennial water irrigation. Cold water irrigation shortened culm length and panicle length and degree of panicle exsertion. The shortening effect appeared great at lower internodes when treated at panicle formation stage but at higher internodes when treated at reduction division stage. Cold water irrigation decreased the number of secondary branches and spikelets per panicle, and increased the number of degenerated spikelets being high degeneration when treated at panicle formation stage. Spikelet sterility and impediment of grain filling were affected by duration of cold water irrigation being great when treated at spikelet primodium differentiation stage and reduction division stage in particular. Grain weight was also reduced. Significant relationship existed between spikelets sterility, grain filling and yield. The degeneration of secondary branches and spikelets correlated with leaf area but spikelet sterility and yield with culm length, panicle length and panicle exsertion.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.4
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• pp.532-539
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• 2015

Inhibition of osteoclast differentiation is the most important target for prevention of inflammatory bone resorption and bone diseases. Here, we investigated the effect of spinach ethanol extract on osteoclast differentiation in RAW264.7 cells. Spinach was extracted with ethanol at a concentration ranging from 0 to 100% (0, 25, 50, 75, and 100% ethanol). Inhibitory effects of receptor activator of NF-${\kappa}B$ ligan (RANKL)-induced osteoclast differentiation were evaluated using tartrate-resistant acid phosphatase (TRAP) stain assay. The most effective eanol concentration for osteoclast differentiation was 100%. Spinach extract (100% ethanol) suppressed RANKL-induced osteoclast differentiation and TRAP activity. Spinach extract (100% ethanol) also suppressed expression of osteoclast differentiation-related marker genes (NFATc1, c-FOS, cathepsin K, and TRAP) and down-regulated RANKL-induced NF-${\kappa}B$ and ERK phosphorylation during osteoclast differentiation. Taken together, our results suggest that spinach extract is effective against reducing osteoclast differentiation through the NF-${\kappa}B$-mediated pathway.

• Korean Journal of Plant Tissue Culture
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• v.28 no.2
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• pp.61-67
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• 2001

Using mature seed-derived callus, optimal conditions for efficient callus growth and plant regeneration, and regeneration efficiency by callus type were investigated in zoysiagrass (Zoysia japonica steud.). Callus induction was highest when the seeds were cultured on MS medium containing 2 mg/L 2,4-D, 0.2 mg/L BAP, 4 mg/L thiamine-HCl and 100 mg/L $\alpha$-ketoglutaric acid. Callus growth was highest when callus were cultured on MS medium containing 0.5 mg/L 2,4-D, 0.05 mg/L BAP, 4 mg/L thiamine-HCl and 100 mg/L $\alpha$-ketoglutaric acid. Plant regeneration was highest when callus was transferred on MS medium containing 3% maltose and 1 mg/L BAP, or 1 mg/L thidiazuron (TDZ). The combinations and concentrations of 2,4-D and BAP were shown to be critical factors for both the frequency and the type of callus. And four morphologically distinct types of callus were induced from the 2,4-D and BAP treatment. Type I,II and III calli produced shoots upon subculture, while the watery callus, type IV produced roots without shoots. Of four types of callus, type I exhibited the maximum frequency (82%) of shoot regeneration and the minimum frequency (4%) of albinism.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.3
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• pp.235-242
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• 2011

In order to improve forage characteristics of Italian ryegrass by genetic transformation, an efficient callus induction from mature seed and optimal plant regeneration system were established using a domestic cultivar 'Kospeed'. Addition of 5 mg/L of 2,4-D showed highest frequency of embryogenic callus induction from mature seeds. N6 medium showed higher frequency of both callus induction and plant regeneration as compared with MS and SH medium. The highest plant regeneration frequency 67% was obtained when embryogenic calli were transferred to N6 medium containing 1 mg/L 2,4-D and 5 mg/L BA. Supplementation of regeneration medium with sucrose at 30 g/L level maximized regeneration frequency as compared to the other concentrations. These data would be very helpful for molecular breeding of domestic Italian ryegrass cultivar through genetic transformation.

• Horticultural Science & Technology
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• v.18 no.3
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• pp.391-394
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• 2000

Girdling and girdling+pinching treatments on 'Sekaiichi' apple remarkably reduced June drop and accelerated fruit growth in early stage of fruit development. Girdling+pinching and pinching reduced bourse shoot growth compared with non-treated control. There were no significant differences in flower bud formation in the following year among treatments. It was assumed that the optimum period for girdling is between 5 days before full bloom and full bloom period.