• Journal of Oral Medicine and Pain
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• 제6권1호
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• pp.23-34
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• 1981

In order to evaluate the correlation of age with development stage on permanent lower posterior teeth. the author exmined the roentgeregrams in standard films taken by intraoral technic and analysed the development phases of 1358 teeth of 500 males ranging from 9 to 15 years. The development was divided into 7 phases : Crown complete (Cr. C.). Root length 1/4(R. 1/4) Root length /2 (R. 1/2) Apical closure complete (A.C) The obtained results were as follows : 1. The formation of roots in full length on posterior teeth was complete as follow : a. Roots of 1st premolar : 12.72 years b. Roots of 2nd premolar : 12.94 years c. Meral Roots of 2nd molar : 13.38 years d. Distal Roots of 2nd molar : 13.46 years 2. The formation of apical forman of premolar was closured as follows : a. Apical foramen of root of 1st premolar : 13.64 years b. Apical foramen of root of 2nd premolar : 13.93 years 3. As a general rule. the mesial roots of second molar were developed earlier than distal roots of second molar. 4. In the correlation of age with the development stage, the regression equations. the correlation coefficents. and the sample numbers were “Y = 0.8370x + 10.2160, r = 0.71(p<0.01), n = 318”on lower first premolar, “Y = 0.6984x + 10.2148, r = 0.71(p<0.01), n = 385”on lower second premolar, “Y = 0.8810x + 10.2040, r = 0.65(p<0.01), n = 344”on mesial Root of lower second molar, and “Y = 0.7310x + 10.7940, r = 0.66(p<0.01), n = 311”on Distal Root of lower second molar respectively.

• The Plant Pathology Journal
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• 제20권1호
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• pp.58-62
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• 2004

White root rot of wild white clover (Trifoliorum repens) caused by isolate BWC98-105 has been first reported in Korea. Typical symptoms on root include water-soaked and dark-brown rot, resulting in complete blight of the whole plant. The fungus grew well at $20-28^{\circ}C$ and produced abundant sclerotia at 10-15 days after full mycelial growth on potato dextrose agar. Sclerotia were brown to dark-brown in color and 1-3 mm in length. When white clover plants were inoculated with mycelial suspension ($10^5$ cfu/ml) of isolate BWC98-105, the plant shoots were killed within 4-6 days and the roots were completely blighted. Sclerotia were also formed on the surface of the root covered with whitish mycelia within 10-15 days in the field. All nine isolates developed high incidences of white root rot disease on white clover seedlings, of which the symptoms were similar to those observed in the fields. Hence, their pathogenicity was confirmed on white clover. The infection rate of the fungal isolates varied from 78.5% to 95.2%, among which BWC98-105 was the most virulent isolate. The weeding efficacy of the fungus was maintained until the following year, leading to a significant reduction of reshooting. The fungus was specifically parasitic to white clover, but not to four lawn species including zoysiagrass (Zoysia japonica) under greenhouse test. The fungus also had no response to some Gramineae species including rice, but caused little damage to five species of Leguminosae.

• Journal of Ginseng Research
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• 제45권1호
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• pp.156-162
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• 2021

Background: It is estimated that 20-30% of ginseng crops in Canada are lost to root rot each harvest. This disease is commonly caused by fungal infection with Ilyonectria, previously known as Cylindrocarpon. Previous reports have linked the virulence of fungal disease to the production of siderophores, a class of small-molecule iron chelators. However, these siderophores have not been identified in Ilyonectria. Methods: High-resolution LC-MS/MS was used to screen Ilyonectria and Cylindrocarpon strain extracts for secondary metabolite production. These strains were also tested for their ability to cause root rot in American ginseng and categorized as virulent or avirulent. The differences in detected metabolites between the virulent and avirulent strains were compared with a focus on siderophores. Results: For the first time, a siderophore N,N',N"-triacetylfusarinine C (TAFC) has been identified in Ilyonectria, and it appears to be linked to disease virulence. Siderophore production was suppressed as the concentration of iron increased, which is in agreement with previous reports. Conclusion: The identification of the siderophore produced by Ilyonectria gives us further insight into the root rot disease that heavily affects ginseng crop yields. This research identifies a molecular pathway previously unknown for ginseng root rot and could lead to new disease treatment options.

• 한국작물학회지
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• 제28권3호
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• pp.299-304
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• 1983

간척지에서 생육된 수도의 근군형성양상을 조사하기 위해 염해의 정도가 서로 다른 3구에서, 시료를 채취하여 다음과 같은 결과를 얻었다. 1. 고염지에서 생육한 수도의 근군은 저염지에서 생육된 수도의 근군보다 천근성을 나타냈다. 2. 고염지에서 생육된 수도의 근군을 구성하는 관근수는 저염지에서 생육된 수도의 근군을 구성하는 관근수보다 적었다. 3. 각 요소에서 출근된 관근수도 고염지에서 생육된 수도가 저염지에서 생육된 수도보다 적었으며, 이와 같은 현상은 이앙후 출근하는 요소에서부터 나타났다. 4. 각 처리구의 관근에 형성된 분지근의 밀도는 고염지에서 생육된 수도가 저염지에서 생육된 수도보다 높은 경향을 나타냈다. 5. 각 처리구의 관근에 형성된 근모의 형성양상은 고염지에서 생육된 수도가 저염지에서 생육된 수도에 비하여 근모형성율이 낮고 또 근모장도 짧은 경향을 나타냈다.

• 대한치과의사협회지
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• 제54권8호
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• pp.658-665
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• 2016

Treatment of immature permanent teeth with irreversibly damaged pulp has been challenging in dental practice because of the lack of apical constriction, thin dentinal walls, and short roots. This may lead to the extrusion of filling materials, and fracture of the root due to its more fragile feature during shaping of the root canal. Apexification with calcium hydroxide or MTA is one of the treatment options for these cases. Although favorable results of apexification have been reported, these treatment procedures do not guarantee the increase of root length and/or width even after a long term period. Thus, treated teeth are still prone to fractures. Recently, pulp revascularization has been proposed as an alternative treatment for immature teeth with necrotic pulp and periapical pathosis. Pulp revascularization allows the stimulation of the apical development and the root maturation. There have been many treatment protocols using various materials such as antibiotics and calcium hydroxide medicament. In this case report, literature review about pulp revascularization and two related cases are presented.

• Journal of Plant Biotechnology
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• 제30권3호
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• pp.241-244
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• 2003

Root cluster section culture, showing high efficient Protocorm-like body (PLB) formation capacity, were established in Doritaenopsis hybrids. Three types of root were obtained from excised shoots in 1/2MS medium containing different concentrations of NAA; \circled1normal roots, \circled2multiple roots and \circled3abnormal root clusters. Those were placed on 1/2MS medium supplemented with 0.5 mg/L thidiazuron for PLB regeneration. PLB regeneration rate was greater in root cluster section cultures (77.8%) compare to normal root tip cultures(30%). Number of PLBs regenerated from root cluster sections were counted over 11 per explant (5.3 per normal root tip).High frequency of PLB regeneration was achieved in root cluster section culture. This result can be used as an efficient method for clonal proliferation of Doritaenopsis hybrids.

• 한국식품영양학회지
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• 제25권4호
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• pp.1086-1091
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• 2012

The objective of this study is to investigate the sensory quality attributes for the development of soy sauce containing Cheongmirae (Smilax china) root. Aqueous extracts of Cheongmirae root and Cheongmirae-soy sauce were used for determining the antioxidant effect by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and sensory evaluation. Chengmirae-soy sauce was prepared by mixing Chengmiae extract (50%) and soy sauce (50%). Cheongmirae extract and Cheongmirae-soy sauce had strong DPPH scavenging effects, compared to that of general soy sauce. In sensory analysis, low intensities of smell, taste and overall preference were observed in Cheongmirae root extract. Various seasoning items, such as anchovy, dried-pollack, katsuobushi, shiitake, radish, and kelp, were used to determine the suitable type of soy sauce containing Cheongmirae root extract. The anchovy-kelp-radish and anchovy-shiitake-kelp-radish among the seasoning items were well-matched with Cheongmirae root extract. From these results, soy sauce containing Cheongmirae root extract may be used as a soup seasoning for Korean style noodles.

• 한국지하수토양환경학회지:지하수토양환경
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• 제24권5호
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• pp.1-10
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• 2019

The effects of liquid phase ozonation on seed dormant alleviation and subsequent seedling growth were studied using two plant seeds of Indian jointvetch (Aeschynomene indica L.) and Indian mallow (Abutilon avicennae Gaertn.). At a constant ozone concentration ($80g/m^3$), contact time varied from 10 to 60 min with 10 min interval. Germination rate, root length, and specific root length were compared after 3-day incubation on gel-medium. The germination rate increased significantly (p<0.05) in the 50 min treatment of Indian mallow by 30% compared to the control. Enhanced root elongation was observed in the seeds of 30 min treatment of Indian jointvetch and 30~50 min treatment of Indian mallow. Specific root length, an indicator of environmental change, did not show significant changes, suggesting the level of ozone treatment has no adverse effect on seedling development. The results indicate that liquid phase seed ozonation can be an effective on-site germination alleviation method in the application of phytoremediation.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.35-35
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• 2017

How do plants take up water from soils especially when water is scarce in soils? Plants have a strategy to respond to water deficit to manage water necessary for their survival and growth. Plants regulate water transport inside them. Water flows inside the plant via (i) apoplastic pathway including xylem vessel and cell wall and (ii) cell-to-cell pathway including water channels sitting in cell membrane (aquaporins). Water transport across the root and leaf is explained by a composite transport model including those pathways. Modification of the components in those pathways to change their hydraulic conductivity can regulate water uptake and management. Apoplastic barrier is modified by producing Casparian band and suberin lamellae. These structures contain suberin known to be hydrophobic. Barley roots with more suberin content from the apoplast showed lower root hydraulic conductivity. Root hydraulic conductivity was measured by a root pressure probe. Plant root builds apoplastic barrier to prevent water loss into dry soil. Water transport in plant is also regulated in the cell-to-cell pathway via aquaporin, which has received a great attention after its discovery in early 1990s. Aquaporins in plants are known to open or close to regulate water transport in response to biotic and/or abiotic stresses including water deficit. Aquaporins in a corn leaf were opened by illumination in the beginning, however, closed in response to the following leaf water potential decrease. The evidence was provided by cell hydraulic conductivity measurement using a cell pressure probe. Changing the hydraulic conductivity of plant organ such as root and leaf has an impact not only on the speed of water transport across the plant but also on the water potential inside the plant, which means plant water uptake pattern from soil could be differentiated. This was demonstrated by a computer simulation with 3-D root structure having root hydraulic conductivity information and soil. The model study indicated that the root hydraulic conductivity plays an important role to determine the water uptake from soil with suboptimal water, although soil hydraulic conductivity also interplayed.

• 생물환경조절학회지
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• 제15권4호
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• pp.352-357
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• 2006

참외의 대목종류가 뿌리의 발달과 활력에 미치는 영향을 조사한 결과는 다음과 같다. 자근묘에 비해 접목묘의 뿌리 생장이 우수하였으며 접목묘 중에서는 세력이 강한 품종으로 알려진 '신토좌', '엘리트호박'의 생장이 좋았다. 뿌리의 활력과 관련된 일비액의 분비는 자근묘보다 접목묘에서 우수하였고 뿌리의 발달과 일비속도의 증가는 지온변화와 높은 상관관계를 나타내어 지온이 상승할수록 뿌리 발달이 촉진되고 근 활력이 우수하였다. 과실의 수량은 접목묘에서 무거웠으나 품질은 자근묘에서 높았다.