• 한국초지조사료학회지
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• 제15권4호
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• pp.259-264
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• 1995

Several benefits provided by white clover (Tnifoliurn repens L.) can be elevated as relationship between its morphological and physiological characteristics is clarified. The experiment was done to analyze the relationship between them in the clover with different leaf size. Individual plants of Osceola (large leaf), Grasslands Huia (medium leaf) and Aberystwyth S184 (small leaf) were grown in 15m plastic pot containing a 1:2:1 soil:sand:Promix mixture for 55 days, and then clipped to remove all fully expanded leaves every 7, 14 or 28 days. To measure the cultivar response, plants were sampled for morphological and physiological parameters on the date (0) after final harvest and 1, 3, 7, 14 and 28 days after the final harvest and then their relationship was analyzed. Osceola had greater leaf area per trifoliolate but less no. of leaves per plant to result in similar total leaf area per plant of all cltivars. Stolon length and no. of growing tips per plant declined with smaller leaf size although the result in biomass was reverse. Stolon of all cultivars showed the greatest fluctuation in total nonstructud carbohydrate during the regrowing period but nitrogen concentrations of all their fractions and dinitrogen fixation did similar patterns. Stolon and root of Osceola, moreover, were the highest ones. Biomass, stolon length and total leaf area per plant of all cultivars were positively correlated to carbohydrate concentration of all frauions and dinitrogen fixation. In Osceola relationship between nitrogen concentration of stolon and the characters showed in Osceola was positively done.

• 한국자원식물학회지
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• 제29권6호
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• pp.712-721
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• 2016

This experiment was conducted to investigate the endophytic bacterium Herbaspirillum spp effect on seed germination and sprout growth of tartary buckwheat. Inoculant concentration (%v/v) and seed soaking time were applied 10, 20 and 40% and 0, 4, 8, 12 hour, respectively. The experiment was carried out in a growth chamber maintained temperature at 20, 25 and $30^{\circ}C$ without light for 7 days. Results showed that, 10 to 20% (v/v) inoculant concentration by 4 to 8 h seed soaking time at $20^{\circ}C$ temperature increased seed vigor rate and total seed germination rate 80-95% and 90-100%, respectively. On the other and, seed inoculation with Herbaspirillum spp. increased hypocotyl length (13-15 cm), root length (8-11 cm), total fresh weight (135-296 g) and total dry weight (7-10 g), compared to control. It is indicated that sprouts growth and yield depends on inoculation concentrations, seed soaking time and temperature. Therefore, it would be suggested that seed inoculation with Herbaspirillum spp. at concentration of 10 to 20% (v/v), soaking time 4 to 8 h and temperature $20^{\circ}C$ promote seed germinations and sprout growth rate of tartary buckwheat.

• 한국조경학회지
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• 제26권3호
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• pp.143-151
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• 1998

To develop restoration technologies of natural environment, which is destroyed through the urbanization, industrialization, and the increase of leisure industry, the development of environmental restoration material and those application is greatly needed. Concerning this current issue, an experiment has been conducted to test and an experiment has been conducted to test and analyze the conditions of nutritonal propagation of willow cutting, which is known as a plant with rapid propagation and good growth capability under bad soil conditions and its wide ecological amplitude. 24 various kinds of willow cuttings -2~6 cuttings for each species -were placed into the earth for 57 days and measured the lengths and the diameters of willow cuttings, the possibility of root formation, the total number, and the total length of new shoots and roots. 23 among 24 willow cuttings tested were showing a great growing capacity and a number of new shoots and roots were observed in a relatively short time. This proved that salix is an adequate plant material for quick environmental restoraton . Besides, those willow cuttings could be classified for different site conditions through comparing the ratio of the underground part to the aboveground in total length. The results are as follows; S. dependens, S. matsudana, S. babylonica are the most suitable species for quick vegetaton and S. gracilistyla,S. myricoides,S. alba 'sercia' for erosioni control.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.230-230
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• 2017

About 200 rice varieties for irrigated and rainfed lowland ecosystems were released in the Philippines, which were bred for improving yield under favorable conditions. Root plasticity plays key roles in maintaining crop productivity under abiotic stressed conditions. We hypothesized that some of these varieties possess root plasticity traits in response to water stressed conditions. This study aimed to evaluate the root system development and dry matter production of 14 randomly selected rice varieties (6 irrigated lowland and 9 rainfed varieties) under progressive drought (PDR) and soil moisture fluctuations (SMF) stress conditions. Two experiments were done in rootbox and line source sprinkler systems (LSS). Each of the varieties was subjected to well-watered (WW), PDR and SMF conditions during vegetative stage in rootbox system while the same genotypes were subjected to different intensities of drought stress under LSS. Under rootbox system, PDR and SMF significantly reduced shoot dry matter production in all varieties relative to their WW controls. Among varieties, NSIC Rc238 (irrigated lowland) showed the least reduction in shoot dry weight (SDW) in both PDR (by 11.8%) and SMF (by 26.9%) conditions. Less reductions in SDW of NSICRc238 were partially attributed to the promotion of L-type lateral roots, thus increasing total lateral root length by 24.2% and 30.7% under PDR and SMF, respectively. In LSS, SDW of NSIC Rc238 under mild drought stress (16-21% soil moisture content (SMC) had 31.8% reduction relative to its WW control (${\geq}22%SMC$) and had lower sensitivity drought index. Compared with the IR64 susceptible check and NSIC Rc9 tolerant check, NSIC Rc238 had higher SDW by 90.8% and 38.6%, respectively. Furthermore, no rainfed lowland varieties included in the experiment performed well under different water stress treatments. The results implied that some other irrigated lowland rice varieties may also possess drought dehydration avoidance root plasticity traits under water-stressed growing environments.

• 치과방사선
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• 제24권1호
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• pp.129-135
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• 1994

This study was performed to evaluate the accuracy of orthopantomogram by measuring the actual and radiographic tooth length and by analyzing the vertical magnification rate. For this study, total 90 teeth of the maxilla and mandible teeth and a dry skull were used. This experiment was attached with metal balls of 1±0.02㎜ at the root and the crown cusp tips of central, 2nd premolar, 1st molar of the maxilla and mandible and the teeth were embedded in dry skull, and then orthopantomogram was taken. The obtained results were as follows: 1. The average of tooth length in orthopantomogram was longer than that of actual tooth length. 2. The average of vertical magnification rate in the orthopantomogram to actual tooth length was 17-26%. 3. Vertical magnification rate of the maxilla teeth was 18-26% and that of mandibular teeth was 17-23%, and the magnification of maxillary teeth was larger than that of mandible teeth(P<0.0l). 4. Vertical magnification rate of posterior area was 22-26% and that of anterior area was 17-18%, and the magnification of anterior area was less than that of posterior area(P<0.01).

• Restorative Dentistry and Endodontics
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• 제36권5호
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• pp.385-396
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• 2011

연구목적: 본 연구는 치근벽의 전처리 개념과 접착제의 중합방법이 레진계 근관충전제의 치근단 밀폐능에 미치는 영향을 평가하였다. 연구 재료 및 방법: 3가지 다른 접착변수를 조합하여 충전한 Resilon-RealSeal 시스템의 근단미세누출을 색소침투법을 이용하여 통상의 가타퍼쳐 충전과 비교하였다. 실험군은 자가부식형 RealSeal primer와 이중중합형 RealSeal sealer를 이용하여 Resilon 충전한 SEDC군, 산부식없이 Scotchbond Multi-Purpose primer를 적용한 후 접착제는 광중합하고 Resilon을 충전한 NELC군, 및 Scotchbond Multi-Purpose의 접착강화제와 접착제를 total etch/wet bonding과 광중합의 술식을 정확하게 지켜서 Resilon을 충전한 TELC군으로 구분하였다. 대조군(GPCS)에서는 통상의 AH26 plus sealer를 사용하여 가타퍼쳐를 충전 하였다. 결과: 치아장축방향의 색소침투는 TELC군에서 GPCS군과 SEDC군에 비해 유의하게 작았다(Kruskal-Wallis test, p < 0.05). 횡단면의 미세누출 점수도 TELC군이 근첨으로부터 2 - 5 mm의 범위에서 다른 군에 비해 유의하게 낮았다(Kruskal-Wallis test, p < 0.05). 결론: 레진계 근관충전제를 사용 시에는, 자가부식형 전처리제와 이중중합형 sealer보다는, total etch/wet bonding 개념과 적절한 광중합을 도모하는 전처리제 및 접착제의 사용이 치근단 미세누출을 감소시키므로 추천된다.

• 한국작물학회지
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• 제57권4호
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• pp.449-455
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• 2012

서양민들레의 시설생산을 위해 배지조성 및 차광정도를 달리한 환경조건에 대한 생육특성과 그에 따른 생리활성 변이를 검토하고자 온실과 실험실 시험을 수행하였다. 서양민들레 시설생산을 위한 적정한 배지조합은 coco peat와 perlite를 각각 70 : 30과 50 : 50으로 혼합한 배지가 coco peat와 perlite 각각의 단독배지보다 생육 및 수량에 있어서 유의적으로 높게 나타났다(p<0.05). 차광정도에 따른 서양민들레의 초장, 근장, 엽수, 근직경, 엽면적, 엽록소 함량 및 생체중은 무차광이 50%와 70%차광보다 유의적으로 높게 나타났다(p<0.05). 총 페놀 함량과 총 플라보노이드 함량은 지하부보다는 지상부에서 높게 나타났다. 총 페놀 함량은 무차광에서 차광보다 높게 검출되었고, 총 플라보노이드 함량은 50%차광에서 가장 높았고 그 다음이 무차광과 70%차광 순으로 높았다. 한편, DPPH 라디컬 소거능과 아질산염 측정을 통한 항산화성은 추출물 농도가 증가할수록 높은 활성을 보였고 지하부보다는 지상부에서, 차광보다는 무차광에서 높은 활성을 보였다.

• Mycobiology
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• 제42권4호
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• pp.416-421
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• 2014

In this study, we examined arbuscular mycorrhizal fungal (AMF) community structure colonizing field-cultivated ginseng roots according of different ages, such as 1- to 5-year-old plant, collected from Geumsan-gun, Korea. A total of seven AMF species namely, Funnelliformis caledonium, F. moseae, Gigaspora margarita, Paraglomus laccatum, P. occultum, Rhizophagus irregularis, and Scutellospora heterogama were identified from the roots using cloning, PCR-restriction fragment length polymorphism and sequence analysis of the large subunit region in rDNA. AMF species diversity in the ginseng roots decreased with the increase in root age because of the decreased species evenness. In addition, the community structures of AMF in the roots became more uniform. These results suggest that the age of ginseng affects mycorrhizal colonization and its community structure.

• 한국토양비료학회지
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• 제22권3호
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• pp.221-227
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• 1989

토성(土性)이 다른 두 토양(土壤)의 압밀상태(壓密狀態)가 대두(大豆)의 근생장특성(根生長特性)과 양분(養分)의 흡수기능처리(吸收機能差異)를 알아보기 위하여 용적밀도(容積密度)와 수분상태(水分狀態)를 달리한 Core에서의 유근신장(幼根伸長)과 용적밀도(容積密度)를 달리하여 pot재배(栽培)하였을 때 근(根)의 총(總)길이와 표면적(表面積), 근반경(根半徑) 및 양분(養分)의 흡수속도(吸收速度)를 조사(調査)한 결과(結果) 다음과 같다. 1. 대두(大豆)의 유근신장(幼根伸長)은 용적밀도(容積密度)가 낮을수록 빨랐으며 양토(壤土)에서는 토양수분(土壤水分) 상태(狀態)가 - 4bar 이하(以下)에서, 사양토(砂壤土)에서는 - 1bar 이하(以下)에서 급격(急激)히 감소(減少)하였다. 2. 유근(幼根)의 신장(伸長)은 ELE경도계(硬度計) 토양강도(土壤强度) 2.0 이상(以上)에서 급격(急激)히 감소(減少)하였으며, 근신장속도(根伸長速度)와 토양강도간(土壤强度間)에는 2차식(次式)으로 표시(表示)되었다. 그러나 사양토(砂壤土)에서 -10bar이하(以下)의 토양수분상태(土壤水分狀態)에서는 경도(硬度)에 관계(關係)없이 근신장속도(根伸長速度)가 낮았다. 3. pot재배시험(栽培試驗) 결과(結果), 뿌리의 총(總)길이는 용적밀도(容積密度)가 $1.2g/cm^3$인 양토(壤土)에서 가장 길었으며, $1.4g/cm^3$인 사양토(砂壤土)에서 가장 짧았다. 세근(細根)의 평균직경(平均直徑)은 사양토(砂壤土)에서 생육(生育)한 것이 양토(壤土)에서 생육(生育)한 것보다 굵었다. 뿌리의 총표면적(總表面積)은 용적밀도(容積密度)가 낮을수록 넓었으며, 양토(壤土)에서 사양토(砂壤土)보다 넓었다. 4. 양분(養分)의 흡수량(吸收量)은 건물생산(乾物生産)이 많은 양토(壤土)에서 많았다. 단위(單位)뿌리표면적당(表面積當) 흡수속도(吸收速度)는 질소(窒素)가 양토(壤土)에서 $597{\sim}753n\;mole/day{\cdot}cm^2$, 사양토(砂壤土)에서 $222{\sim}365n\;mole/day{\cdot}cm^2$이었으며, 용적밀도(容積密度)가 높은 토양(土壤)에서 높은 값을 보였다. K는 $99{\sim}175n\;mole/day{\cdot}cm^2$ P는 $26{\sim}46n\;mole/day{\cdot}cm^2$이었고, Ca와 Mg는 각각(各各) $175{\sim}230n\;mole/day{\cdot}cm^2$, $163{\sim}205n\;mole/day{\cdot}cm^2$의 범위(範圍)를 보였으며 토양간(土壤間)의 차이(差異)는 질소(窒素)보다 적은 경향(傾向)이었다.

• 한국작물학회지
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• 제48권6호
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• pp.484-489
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• 2003

무기질 비료 및 퇴비를 36년간 장기 시용한 논 토양에서 벼 뿌리의 분포양상을 구명하기 위하여 무비, 퇴비단용, 삼요소, 삼요소+퇴비, 삼요소+규산구의 벼 뿌리 관련 특성을 조사하였다. 본 시험은 평택통에 화삼벼를 주당 3본씩 손이앙 하였으며 삼요소구의 시비량은 N-$\textrm{P}_2\textrm{O}_5$-$\textrm{K}_2\textrm{O}$ kg $\textrm{ha}^{-1}$=150-100-100를 시용하였고 규산은 ha당 500kg, 퇴비는 ha당 10,000kg를 시용하였다. 근계특성 분포 특성을 요약하면 다음과 같다. 지상부의 건물중은 시비량이 많을수록 높은 경향이었다 그러나 뿌리 건물중은 삼요소구에 비하여 삼요소+퇴비에서 많았으며, 총근장은 무비에서 컸다. 뿌리 건물중은 삼요소+퇴비구에서 높았다 토심별 근장밀도(cm $\textrm{cm}^{-3}$)는 무비구의 주간하 0-5cm에서 가장 높았고 토심이 깊어질수록 적어지는 경향이었고 주하와 주간하의 차이는 심토로 갈수록 적어지는 경향이었으나 퇴비단용구는 토심 15-20cm의 주간하에서 주하와 차이가 컸다. 토심별 근중밀도(mg $\textrm{cm}^{-3}$)는 삼요소+회비구에서 가장 높았다. 비근장은 삼요소+규산구에서 가장 낮았다. 뿌리깊이 지수는 퇴비단용구가 높았으며 근장으로 계산한 지수가 근중으로 계산한 지수보다 높았다.