• Title/Summary/Keyword: Root form

Search Result 472, Processing Time 0.03 seconds

Algebraic Analysis for Partitioning Root and Stem Lodging in Rice Plant

  • Chang, Jae-Ki;Yeo, Un-Sang;Lee, Jeom-Sig;Oh, Byong-Geun;Kim, Jeong-Il;Yang, Sae-Jun;Ku, Yeon-Chung;Kim, Ho-Yeong;Sohn, Jae-Keun
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.51 no.6
    • /
    • pp.539-543
    • /
    • 2006
  • Lodging is classified as root lodging caused by the loss of supporting force in the root, bending caused by the deformation of the stem and breaking where the stem breaks down as loads exceeding critical elasticity were applied. This research excluded breaking which is not in a state of equilibrium and tried to partition the level of lodging using an algebraic model in root lodging and stem lodging, or bending. When a vertical load was applied, the deformation of the stem of rice plant showed the form of a quadratic equation. The trace of the panicle neck in the process of lodging was an ellipse-shape. When loading was pure root lodging, the trace of the panicle neck became a circle of which culm length is the radius. When it was a pure stem lodging, the trace of the panicle neck is an ellipse of which major axis is culm length and minor axis is 0.64* culm length. When both stem lodging and root lodging occurred in a natural setting, the partitioning of lodging can be calculated by a formula using eccentricity of an ellipse, S=e*100/0.768(S is the ratio of stem lodging in the whole lodging, e is eccentricity of the ellipse). This method is expected to be useful in simple lodging partitioning. We could also calculate the partitioning of stem lodging and root lodging as units of angles as an accuracy method, by using a straight line calculated by differentiating a quadratic equation of stem deformation at the origin of the coordinates. These two methods for dividing root and stem lodging showed different values. However, each of them showed almost same values with different lodging degree in one plant.

Diagnosis of Phythopthora sp. and Its Concentration by Potato Slices in Series Culture Soils.

  • Lee, Jung-Sup;Park, Jong-Hwan;Han, Kyeong-Suk;Park, Young-Mun
    • Proceedings of the Korean Society of Plant Pathology Conference
    • /
    • 2003.10a
    • /
    • pp.129.2-130
    • /
    • 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.

  • PDF

THE EFFECT OF ND : YAG LASER ON DENTINAL TUBULE SEAL AFTER ROOT END RESECTION (치근단절제시 노출된 상아세관의 밀폐효과에 대한 Nd : YAG 레이저의 효과)

  • Shin, Kwang-Chul;Hong, Chan-Ui
    • Restorative Dentistry and Endodontics
    • /
    • v.21 no.1
    • /
    • pp.311-320
    • /
    • 1996
  • If root and resection is done during surgical endodontic treatment, newly exposed dentinal tubules form pathways between the canal and the peripheral tissue. Nd : YAG laser was used to block this phenomenon, and its effect was studied with dye penetration and SEM techniques. 40 intact single rooted teeth were divided into 4 groups(10 each) : control group and test groups, in which retrograde cavity surface, cutting surface, retrograde cavity surface & cutting surface were treated with laser(1 watt 15pps) and finally retrograde filling with IRM was conducted. After that, they were stained with 2 % methylene blue, sectioned and evaluated by the maximum infiltration depth. And to observe surface change, they were prepared for SEM. The results were as follows ; 1. All experimental groups showed microleakage with variation in amount. 2. The 2nd group which treated both the retrograde cavity and cutting surface showed significantly less microleakage than the other groups(p<0.05). There was no significant difference between groups treated on one side only. 3. As a result of SEM observation of dentin surface, obstruction of dentinal tubules with marble shaped granules, which were different from normal dentin could be seen. Cracks could be seen also. 4. In summary of this experiment, it is thought that effort to obstruct the exposed dentinal tubules as well as retrograde cavity after root end resection is needed.

  • PDF

Pharmacognostic Evaluation of Ratanjot-Arnebia nobilis Rech.f.

  • Khatoon, Sayyada;Mehrotra, B.N.;Mehrotra, Shanta
    • Natural Product Sciences
    • /
    • v.9 no.4
    • /
    • pp.286-290
    • /
    • 2003
  • Ratanjot is attributed to eight species of Boraginacae species belonging to genera Alkanna, Arnebia, Maharanga and Onosma and regarded as one of the important herbal drugs of indigenous systems of medicine. The root and root stock, which form the actual drug, are considered to be an anthelmintic, antipyretic and antiseptic. They are also claimed to be useful in burn, eczema, wounds and eruptions, and used for treating the diseases of eyes, bronchitis, abdominal pains, itch, etc. Several workers reported that the Naphthaquinones (arnebins), the main active constituents of the drug, are responsible for its colour and therapeutic efficacy. It is claimed that the Arnebia nobilis was imported to India from Afghanistan but the red coloured roots resembling with A. nobilis were found to be gathered by local people for commercial purposes during the course of botanical surey of Himalayan region. Hence, it is decided to evaluate Arnebia nobilis pharmacognostically. The important macro-microscopic features of this species are roots 1-5 cm broad; outermost xylem with broad vessels and innermost with groups of radially arranged narrow vessels while the middle region occupied by alternate rings of clusters of broad and narrow vessels and presence of pith. Besides the percentage of arnebin-1, -3 and 4 are 9.37, 10.53 and 1.72 respectively.

Direction to Develop Domestic Technology for Waterproofing and Root Penetration Resistance in Comparative Study of Overseas Technology on Green Roof System (국내외 옥상녹화 기술현황분석을 통한 국내 방수.방근기술의 개선방향연구)

  • Kwon, Shi-Won;Bae, Kee-Sun;Oh, Sang-Keun
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2007.04a
    • /
    • pp.13-17
    • /
    • 2007
  • The green roof industry have been developed with Europe, North America, Japan. At the same time, being recognized the important of green roofs in domestic industry and we just start to develop the relative technology as analyzing the future direction of advanced technology. Recently, local self-government including Seoul support the system for green roof which provide 50% of working expenses form of Matching Fund by Seed Money. As years go by, the number of build up the green roof has gradually increased to be proved. At this result caused by management of system in government, unstructured construction system, low development of support technology. In this study as analyzing the present of technical development, supporting by law and system for the advanced waterproofing and root penetration resistance technology, we suggest the development direction of it to be compared with application advanced technology and we could strengthen the international competitiveness to be industrialized the green roof considering system, technology, human infrastructure.

  • PDF

Patterns and Characteristics of Fatigue Failure in Cruciform Fillet Weld Joint (십자형 필릿 용접부에서의 피로파괴 형상과 특성)

  • Lee, Yong-Bok;Chung, Joon-Ki;Park, Sang-Heup
    • Journal of Welding and Joining
    • /
    • v.29 no.4
    • /
    • pp.67-72
    • /
    • 2011
  • The proportion of the welding in the production process of machinery, buildings and marine structures is increasing and the joining are mainly conducted by butt and fillet weld. In the case of fillet weld, the shape of structures is complicated depending on the constraint on the geometry of the structures, therefore, the full penetration is mostly difficult. Accordingly, it is necessary to establish safe and economical criteria of design of the structures through the strength based on the penetration state of the fillet weld. Patterns of fatigue failure in cruciform fillet weld jont appear in the form of the root, toe and mixed failure. In the case of toe and mixed failure, the fatigue strength is higher than root failure. Therefore, we have to make the enough depth of penetration or perform the welding work through improving the fatigue strength of cruciform joints in welded structures. So it is necessary to optimize the penetrated depth in the range of the possible mixed failure and find the way in the cost-effective design to lessen the amount of the welding work.

First step of root canal therapy-access cavity preparation (근관치료의 시작 - 치수강 개방)

  • Song, Minju
    • The Journal of the Korean dental association
    • /
    • v.56 no.10
    • /
    • pp.572-580
    • /
    • 2018
  • Adequate access cavity is the key to achieving endodontic success. The aims of the access cavity can be considered as follows: 1) Creation of a smooth unimpeded pathway for instruments to canal orifices 2) Removal of the entire roof of the pulp chamber in order to inspect the pulp floor, 3) Preservation of natural tooth substance consistent with the above. Recently, contracted endodontic cavities based on minimally invasive endodontics has introduced. This has the benefit of preserving the pericervical dentin more than traditional access cavity with achieving long-term success. However, some studies reported controversial results regarding root canal detection, instrumentation efficacy (noninstrumented canal area, hard tissue debris accumulation, canal transportation, and centering ratio) as well as fracture resistance. Therefore, further studies are required for accepting contracted access cavity, and modified form of traditional and contracted access cavity could be considered.

  • PDF

Growth Characteristics of Teratoma Shoot derived from Crown Gall Callus of Nicotiana tabacum cv. NC2326 (연초 Crown Gall Callus 유래 Teratoma Shoot의 생장특성)

  • 양덕춘;최광태
    • Journal of the Korean Society of Tobacco Science
    • /
    • v.13 no.1
    • /
    • pp.36-42
    • /
    • 1991
  • The present study was conducted to obtain some basic information on the shoot formation from crown gall callus and the characteristics of teratoma shoot derived from crown gall induced by inoculation of Agrobacterium tumefaciens C58. Crown gall callus could be continuously cultured on the phyohormone free basic medium. The growth of crown gall callus was inhibited when BA were added to the cultural media. Shoot formation from crown gall callus fail to be initiated except teratoma shoot which induced on the phytohormone free medium after several subculture on rare occasions. Teratoma shoot could not form root and grow as normal shoot. Addition of BA to cultural media was not effective for shoot elongation, reduction in multiple shoot formation, but IBA was somewhat effective for shoot elongation of teratoma shoot, never for root formation.

  • PDF

A Bioassay on Susceptivity of Selected Species to Phytotoxic Substances from Tomato Plants (토마토식물의 독성물질에 대한 타 식물의 민감도 검정)

  • 김영식
    • Journal of Plant Biology
    • /
    • v.30 no.1
    • /
    • pp.59-67
    • /
    • 1987
  • To verify allelopathic effect of tomato plants a number of labovatory experiments, seed germination and seedling growth with aqueous extracts and leachates form the tomato plants, have performed. Germination percentage of the tested species was decreased by treatment with leaf, stem and root extracts as extracting time elapses. The leaf extract more inhibits the germination of the seeds than both stem and root extracts. Leachate collected from the tomato plants decreases as much as 50% of the growths in elongation as well as dry weight of seedlings of lettuce and egg plant. It is observed that with a paired-plants grown in U tube pot the tomato roots have excreted allelochemicals to inhibit the growth of the tested species and volatile substances from the tomato plants have suppressed to dry weights of lettuce, to elongation and dry weights of grapevine planted near the tomato plants.

  • PDF

Inhibitory Effects of the Extracts from Eleutherococcus senticosus Maxim. on Histamine-release from Rat's Mast Cell

  • Jeong, Jae-Hun;Kim, Young-Seon;Baek, Seung-Hwa;Park, Kwang-Hyun
    • Korean Journal of Plant Resources
    • /
    • v.24 no.3
    • /
    • pp.324-329
    • /
    • 2011
  • Eleutherococcus senticosus Maxim. has been successfully used as an oriental medicine for various diseases including allergic disorders. Histamine is a major factor on various allergic responses and it is reported that histamine was released from mast cells by sensitization of allergens. In this study, ethanol extracts from E. senticosus Maxim. were prepared and the composition was analyzed by high performance liquid chromatography. The eleutheroside B as a primary effective component of E. senticosus was contained approximately 225 mg/kg in root bark extracts. The extracts were found to significantly inhibit compound 48/80-induced histamine release form mast cells in dose dependent manner. However the extracts had low cytotoxicity on the mast cells with MTT assay. These results showed that E. senticosus Maxim. extracts may be the effective materials on inflammatory disorders.