• Journal of Plant Biology
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• 제36권1호
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• pp.35-42
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• 1993

This study deals with the effect of dwarf growth for the wood and the structural changes of cambium in Pinus koraiensis subjected to water stress. The length and wall thickness of tracheary elements in dwarf trees was shorter and thicker than that in normal trees. The redial width and cell number of the annual rings are narrower and smaller in dwarf trees than those in normal trees. In serial tangential sections, the frequency of anticlinal division is low and loss of cambial initials is small in dwarf trees. The length of cambial initials in water deficit, trees are slightly shorter than that in normal trees, and the instructive growth of cambial initials during differentiation of xylem mother cells is inactive in dwarf trees. Thus, it is interpreted that the shortening of tracheary elements in dwarf trees is due to the fact that the length of cambial initials are shortened and the intrusive growth of those during differentiation of xylem mother cells is inactive. The structural variations in the wood of naturally occurring dwarf trees are similar to those of trees subjected to artificial water stress. Therefore, it is suggested that the variation of xylem element in dwarf trees are related to water conditions.

• Journal of Plant Biology
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• 제29권2호
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• pp.129-133
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• 1986

Transections of the stem region close to the shoot apex show the occurrence of an outer, complete ring of procambium and an inner group of discrete procambial strands. From the outer ring, small, discrete vascular bundles and vascular cambium originate, while the inner group forms the discrete, medullary vascular bundles with intrafascicular cambium. Secondary thickening is essentially due to the activity of the cylinder or complete ring of vascular cambium that originates from the procambium. The medullary intrafascicular cambia also form some secondary tissues. The vascular cambium produces secondary xylem inwards and secondary phloem outwards as in the normal secondary thickening process. The distinctive feature, however, is perpetual discreteness of the medullary vascular bundles. No successive series of cambia or secondary vascular bundles are found.

• Journal of Plant Biology
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• 제34권1호
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• pp.9-18
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• 1991

본 연구는 자연상태에서 자란 12종의 왜소개체에 있어 목부구조의 변이에 대한 왜소생장의 영향을 검토하였다. 통수요소 및 섬유의 길이와 접선직경이 정상개체보다 왜소개체에서 더 짧고 좁게 나타났다. 방사조직의 높이도 정상개체보다 왜소개체에서 낮았다. 동일 연륜의 방사폭과 연륜내 세포수는 정상개체보다 왜소개체에서 좁고 적었다. 송백류에서 춘재에 대한 추재의 비는 정상개체보다 왜소개체에서 높게 나타났다. 피자식물의 도관요소의 mesomorphy 정도는 정상개체보다 왜소개체에서 낮았다. 이와 같이 왜소생장은 수분결핍과 같은 환경요인에 의해 극도로 느린 생장을 한 결과로 해석된다.

• 한국응용곤충학회지
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• 제11권2호
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• pp.55-60
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• 1972

1. 지엽에 있어서 배수선의 또는 감수성인 품종이 저항성인 품종보다 평균 6개 이상 많았으며 중간성과 저항성 품종간에는 차이가 없었다. 2. 엽맥의 도관절의 길이는 감수성인 진흥, 김마제 수원 213호 등이 저항성 품종보다 길었으며 팔달 시로 가네 농릴 6호 등은 차이가 없었다. 3. 도관의 직경은 김마제쓱 수원 213호가 다른 4 품종에 비하여 길었으나 저항성품종과 감수성 품종간에는 유의차가 없었다. 4. 6-7엽기에 이른 뿌리의 후생도관은 진흥 김마제가 시로가에, 농릴 6호 보다 휠씬 많았으나 수원 213호는 예외적으로 후생도관수가 가장 적었다. 5. 저항성인 시로가네의 즙액에서는 감수성품종에 비하여 세균의 증식이 현저하게 억제 되였고 다른 품종들 간에는 차이가 없었다. 6. 열처리된 즙액에서는 저항성 품종이나 감수성품종에 관계없이 세균증식이 비슷하였고 전체적으로 신선한 즙액에서 보다 세균수가 훨씬 적었다.

• Journal of Plant Biotechnology
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• 제3권2호
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• pp.45-57
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• 2001

Trees have the ability to undergo secondary growth and produce a woody body. This tree-specific growth is affected by the secondary vascular system and the developmental continuum of secondary phloem and xylem. Secondary growth is one of the most important biological processes on earth. Considering its economic and environmental significance, our knowledge of tree growth and development is surprisingly limited. Trees have received little attention as model species in plant science, as most Plant biology questions can be best addressed by using herbaceous model species, such as Arabidopsis. Furthermore, tree biology is difficult to study mainly due to the inherent problems of tree species, including large size, long generation time, large genome size, and recalcitrance to biotechnological manipulations. Despite all of this, one must rely on trees as models to study tree-specific questions, such as secondary growth, which cannot be studied effectively in non-woody model species. Recent advances in genomics technology provide a unique opportunity to overcome these inherent tree-related problems. Several groups, including our own, have been successful in studying the biology of wood formation with a variety of hardwood and softwood species. In this article, 1 first review the current understanding of tree growth and then discuss the recent attempts to fully explore and realize the potential of molecular biology as a tool for enhanced understanding of secondary growth.

• 생약학회지
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• 제1권3호
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• pp.81-92
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• 1970

So far, the cultivated peony is known to be originated from an indigenous species, Paeonia albiflora $P_{ALLAS}$ var. trichocarpa $B_{UNGE}$ (PAT). In this study, these two species were morphologically examined in the external and internal feature and in the pattern of callus formation by tissue culture. Also, they were compared with another indigenous species, P. japonica $M_{IYABE}$ et $T_{AKEDA}$ var. pilosa $N_{AKAI}$ (PJ), which were regarded as being scarcely related to them. The root of the cultivated peony is massive consisting with several storage roots, each of them is a hypotrophic and fusiform. The root of PAT consists of several storage roots, each of them is branching and slender. And the storage root of PJ is short, bended buried horizontally, protruding a number of corpulent lateral root. The secondary xylem of the cultivated peony is small clusters of vessels and xylem fibres are arranged in scalariform and among these cluster, single vessel is joined, but that of PAT is small clusters of vessels are arranged in separate scalariform but are not connected with each other and that of PJ is vessels and xylem fibers are grouped together in elongated clusters that radiate outward from the center. Protoxylem of the cultivated peony is surrounded by four large metaxylem, but that of PAT and PJ by seven. On the other hand, the callus formation patterns of these peonies were different; the cultivated peony callus is formed in an orderly fashion by the mammalate meristematic cell groups, PAT callus is in disorder by the meristematic cells arranged in linear, and PJ callus is in order by the meristematic cells arranged in linear. By the comparison of three different plants in the anatomical appearance and the callus formation pattern, it is evident that the cultivated peony is not derived from PAT.

• The Plant Pathology Journal
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• 제20권2호
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• pp.81-84
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• 2004

Branched broomrape (Orobanche ramosa) is a holo-parasitic flowering plant that attaches to the root of its host, green plant, by means of a specialized structure known as haustorium. Following successful contact and penetration on susceptible plant root, complex tissue of Orobanche cells is formed which is known as the tubercle. Newly formed tubercles contain high activity ofindole-3-acetic acid (IAA). Triiodobenzoic acid (TIBA), as an inhibitor of IAA polar transport, was utilized to investigate the supply and requirement of auxin to the developing O. ramosa on tomato plant. There was no significant reduction in the incidence of O. ramosa per pot of different TIBA treatments. However, infection severity in terms of the number of O. ramosa shoots that emerged per plant and number of attachments per plant root system were significantly reduced by 60 % and 45 % on TIBA treated plants, respectively. Histo-logical studies revealed conspicuous delay in the initiation of xylem vessel differentiation inside tubercles of the TIBA treated tomato plants. Also, differentiated vessels showed thinner secondary wall deposition, and improper alignment within bundles inside those tubercles. They were wider and shorter in diameter in comparison to those of untreated plants. These findings were attri-buted to the short supply of IAA required for normal development, and to the xylem vessel differentiation of O. ramosa tubercles on infected tomato. Hence, this parasitic flowering plant seems to depend upon its host in its requirements for IAA, in a source to sink relation-ship.

• Journal of Plant Biology
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• 제3권2호
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• pp.29-34
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• 1960

From the view point of phytopathological anatomy, the author has tried to study the effect of the shoot cluster disease virus on the internal structure of vascular tissues of chinese date tree (Ziziphus jujuba var. inermis Rehd.) comparing healthy checks and diseased plants. The materials were collected at the several sites, Kumgock-Ri, Masuc-Ri, Kyungi-Do, and near the campus of Korea University and around the area of Chongam-Dong, Seoul City, from August 15th to September 5th 1959. The leaf materials of healthy and diseased plants are fixed and aspirated in two kinds of killing solutions, formalin-acetic acid alcohol solution and Craf III solution. Sections were cut at 5-10$\mu$ thickness and stained with the double staining reagents of safranin and fast green. In this experiment the author has observed that there are marked structural changes in the infected plants in contrast of healthy checks. As figures 3-7 show that the following characteric changes have taken place on infected plants: 1) the arrangement of irregularly developed sieve elements in phloem, 2) the degeneration of phloem elements, 3) the irregular arrangement of epidermis in mid-vein, 4) more necrosis is observed among the parenchymatous cells, 5) abundant accumulatin of starch grains in parenchymatous cells, . In contrast to the above irregularities caused by the virus disease, the healthy checks appear normal structures as shown in figures 1 and 2. In adding to the all features noted above, the author could also observe an interesting feature that the xylem elements in mid-vein vascular bundle tissues are considerably disorganized to show the unspecialized vessel elements, the irregularly arranged xylem elements. However, this kind of irregularities which occur in xylem under the virus infection has not been reported previously. The features noted on the internal structure of vascular bundle under the condition of infection by the shoot cluster disease on chinese date trees appear to be more or less closely similar to the symptoms of the bunchy-top of banana and the yellow dwarf disease of barley in respect to the fact that whether phloem necrosis takes place as a primary symptom or a secondary symptom. In all these disease, primary histological changes of hypoplasia and hypertrophy are preceeded by the necrosis of phloem.

• Journal of Plant Biology
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• 제34권1호
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• pp.67-75
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• 1991

한국산 아욱목 식물 4과, 5속 10종의 목부 해부학적 형질을 비교 관찰하여 과 및 속간의 목부의 특수화 정도를 검토하였다. 담팔수과 담팔수속의 목부는 산공재로서 각상 도관이 주로 방사배열(2-14 세포폭)이고 이관 및 반관유조직이 드물게 나타난다. 산공재로서 단독분포도관과 유조직이 계단상 1열대를 보이는 피나무과 식물 중 피나무속은 도관이 각상이고, 방사조직이 절화와 타일세포가 존재하며 장구밥나무속은 원형도관을 보인다. 아욱과 무궁화속은 환공재로 도관은 원형 단독분포이며 유조직이 2열로 나타난다. 그리고 벽오동과 벽오동속은 환공재로 원형 단독분포이며, 반관연합익상 및 이관 다열 유조직이 나타난다. 그리고 유조직에는 전분과립이 많이 나타난다. 도관요소의 배열, 모양, 길이, 직경 및 청공판 각도와 주축유조직의 분포 등의 특징에 의한 이들 과간의 계통순서는 담팔수과(담팔수속) 피나무과(피나무속 장구밥나무속) 아욱과(무궁화속) 벽오동과(벽오동속) 순으로 사료된다.

• 한국산림과학회지
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• 제77권3호
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• pp.283-293
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• 1988

산공재(散孔材)인 왕버들(Salix glandulosa Seemenn)과 환공재(環孔材)인 굴참나무(Quercus variabilis BI.)의 뿌리, 줄기 및 가지에 있어서 2기(二期) 목부조직(木部組織)을 해부학적(解剖學的)으로 비교관찰(比較觀察)하였다. 굴참나무의 뿌리의 도관분포(導管分布)는 줄기와 달리 산공형(散孔型)이다. 뿌리의 연륜(年輪) 경계(境界)는 양(兩) 수종(樹種)에서 대체(大體)로 불분명(不分明)하다. 도관요소(導管要素) 및 대섬유(大纖維)는 뿌리에서 제일 길고, 가지에서 가장 짧다. 또한 도관(導管)의 직경(直徑)은 뿌리, 줄기, 가지의 순(順)으로 좁아진다. 횡단면상(橫斷面上)에서 도관(導管)의 단위면적당(單位面積當) 분포수(分布數)는 가지에서 제일 많고 뿌리에서 가장 적다. 도관요소(導管要素)의 천공(穿孔)은 두 수종(樹種) 모두 단천공(單穿孔)이고, 천공판(穿孔板)의 경사각(傾斜角)은 뿌리, 줄기, 가지의 순(順)으로 작아진다. 접선단면상(接線斷面上)에서 방사조직(放射組織)은 뿌리가 줄기나 가지에 비(比)해 높은 반면(反面), 단위면적당(單位面積當) 분포수(分布數)는 뿌리에서 줄기나 가지에 비(比)해 적다.