• Journal of Plant Biology
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• 제36권1호
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• pp.29-34
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• 1993

Observation was made on early ontogeny of vascular cambium in the cotyledonary node of Pinus koraiensis seedling in order to clarify the cambial ontogeny of the node which was hardly elongated. In transverse view, the derivatives by the early periclinal divisions at the outer region of the procambial strands differentiated to protophloem with establishing a certain degree of radial seriations. Later, some cells in the central region of the procambial strands begin divide periclinally, eventually the cells, differentiate gradually to the vascular cambium. In tangential view, early procambium is consisted of homogeneous short cells with transverse end walls which are tansformed into the long cells and short cells gradually. The long cells continue intrusive growth and the short cells repeat transverse division. Finally, the long and short cells differentiated to cambial fusiform initials and ray initials respectively. In tangential section, the differentiation pattern of cambial initials resembles that of the stem of Ginkgo biloba. But in transverse view, the characteristics in the origin of vascular cambium of the cotyledonary node resembles that of root. The vascular cambium in cotyledonary node is completed after eleven prophylls were formed.

• Journal of Plant Biology
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• 제35권4호
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• pp.359-364
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• 1992

은행나무 유식물에서 유관속형성층은 성숙한 잎을 포함하여 5장의 잎이 자라고 있을 때 제일 먼저 자엽절에서 발생되고, 이어서 지하기관인 배축-뿌리로 그리고 지상부의 줄기로 즉, 양쪽 방향으로 분화되었다. 접선면 관찰에서 자엽절의 유관속형성층 발생유형은 줄기와 같고 뿌리와는 다르다. 자엽절에서 초기의 전형성층은 동일형의 세포로 구성된 균일구조를 이루고, 발생이 진행됨에 따라 신장생장을 하는 일부세포와 횡단분열을 하는 나머지 세포의 두 종류 세포로 된 비균의 구조로 전환된다. 신장을 하는 긴 세포로부터 유관속형성층의 방추형 시원세포가 그리고 횡단분열을 하는 짧은 세포로부터 방사조직 시원세포가 기원된다. 그러므로 방추된 시원세포는 심한 관입생장을 거쳐서 발생된다.

• 한국작물학회지
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• 제54권3호
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• pp.307-313
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• 2009

Mature dry seeds of Korean cultivars, Daepungkong, Muhankong, Myeongjunamulkong, Somyeongkong, Sowonkong, Jinpumkong, and Pungsannamulkong were used. The influence of antibiotics on elimination of Agrobacterium growth and shoot regeneration was estimated with cotyledonary node. Cefotaxime and timentin at the concentration of 250 and 500 mg/l suppressed Agrobacterium, especially cefotaxime was an efficient antibiotic to suppress Agrobacterium in all cultivars. While carbenicillin and timentin at the concentration of 50 and 100 mg/l were not sufficient to control the development of Agrobacterium, respectively. Cefotaxime and timentin represented high shoot formation rates compared with carbenicillin. Carbenicillin at low concentrations did not effectively suppress Agrobacterium and also had no effect on shoot development. Cefotaxime at the concentration of 250 mg/l showed maximum frequency of shoot regeneration in cvs. Somyeongkong and Sowonkong. Furthermore, on medium containing cefotaxime, shoot was more quickly formed than the other antibiotics. The use of cefotaxime was very useful for elimination of Agrobacterium growth with cotyledonary node of Korean soybean cultivars.

• Journal of Plant Biotechnology
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• 제38권3호
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• pp.198-202
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• 2011

Agrobacterium과 자엽절 절편 공동배양으로 오이 형질전환체를 생산하였다. 오이 자엽절 절편 (c.v. Eunsung)은 선발 마커로서 nptII유전자와 유용유전자로서 DQ유전자가 포함된 pPZP211를 EHA101에 형질전환하여 공동 배양하였다. 3회 반복실험으로부터 평균 형질전환 빈도는 4.01%를, 최대 빈도는 5.97%를 보여 주었다. Paromomycin항생제 저항성을 갖는 9개의 식물체를 선발과정을 통해 얻었으며, Southern blot 분석에 의해 6개 식물체의 genome에 nptII유전자자 안정적으로 도입되어 있음을 확인할 수 있었다.

• 한국자원식물학회지
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• 제32권3호
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• pp.237-243
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• 2019

Soybean is the one of recalcitrant legume species for shoot induction. Shoot regeneration via direct organogenesis was investigated in five soybean cultivars, 'Dawon', 'Pungsan', 'Daewon', 'Taekwang' and 'Chongdoo 1' by using cotyledonary node explants. Out of 5 soybean cultivars, an efficient shoot regeneration condition was developed in the two soybean cultivars, 'Dawon' and 'Pungsan'. When various kinds of plant growth regulators with different concentration were estimated, the optimum medium condition for shoot induction in both soybean cultivars was MS + B5 vitamin supplemented with BA at concentration 2 mg/L. In addition, shoot formation efficiency was increased with 97.09% and 93.88% by the pretreatment of BA onto the explants before in vitro culture in both cultivars. Shoot induction in 'Dawon' cultivar was originated from epidermal tissue and sub-epidermal layers when histological changes were investigated under shoot regeneration after culturing cotyledonary node segments on shoot induction medium for 0 to 21 days. Especially, cell dedifferentiation was observed from parenchyma cells to meristematic cell in 3-day cultured segments.

• 한국자원식물학회지
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• 제32권1호
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• pp.19-28
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• 2019

An efficient shoot regeneration condition for pea cv. 'Sparkle' was developed by using optimum explant, plant growth regulator concentrations, and pretreatment of BA onto explant. The average shoot number per explant showed the highest on two kinds of shoot induction media (MSB5 media containing 2 mg/L BA and a combination of 2 mg/L BA and 1 mg/L TDZ) when cotyledonary node explants were cultured. Moreover, the pretreatment of explant in 200 mg/L BA solution was found to be more effective in shoot induction than that of non-pretreatment. By histological study, cell division and proto-meristem were formed near the surface of the sub-epidermal and epidermal cell layers of cotyledonary node in earlier than 3 days after culture. The analysis of genetic stability of regenerants by using thirteen ISSR markers showed that in vitro regenerated plants showed polymorphism with 8.3% compared with their mother plants.

• 한국작물학회지
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• 제37권5호
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• pp.419-424
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• 1992

콩에서의 조직배양 가능성을 알아보고자 콩 유묘를 기내에서 배양시킨 뒤, 여러 부위를 채취하여 각기 다른 배지 치상한 결과는 다음과 같다. 1. 줄기정단조직 배양에서는 대부분 shoot가 분화되어 완전한 식물체를 얻을 수 있었다. 2. 자엽절 조직배양에서는 multiple shoots가 나타나 대량증식에 유용했으나 배지에 따른 영향이 컸다. 3. 배축 및 상배축 조직배양에서는 callus만 분화되엇다. 4. 엽조직배양에서는 callus 분화 후 계대배양했을 때 shoot가 분화되었으나 완전한 식물체를 얻기는 힘들었다.

• Journal of Plant Biotechnology
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• 제32권4호
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• pp.257-262
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• 2005

Agrobacterium과 자엽절 공동배양으로 대두 형질전환체를 생산하였다. 멜론 (슈피VIP품종)의 자엽절 절편은 선발 마커로서 bar와 reporter로서 gus유전자가 포함된 pPTN289 또는 선발마커로서 nptII유전자와 reporter로서 gus유전자로 제작된 pPTN290벡터를 LBA4401, GV3101, EHA101에 각각 형질전환하여 공동 배양하였다. 최대 형질전환빈도(0.16%)는 EHA101 (pPTN289)균주로 공동배양한 자엽절 절편을 glufosinate가 첨가된 선발배지에서 얻을 수 있었으며, 최종적으로 glufosinate저항성과 잎 ($T_0$), 화기 ($T_0$), 종자 ($T_1$) 및 유식물체 ($T_1$)에서 GUS양성반응을 나타내는 5개체를 얻었다. Southern분석에 의하여 GUS유전자가 멜론 genomic DNA에 도입되어 있음을 확인하였다.

• Journal of Plant Biology
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• 제28권4호
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• pp.285-296
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• 1985

To examine the differentiation and transition of vascular system in Prunus davidiana FR., the mature embyro and developing seedlings were embedded in paraplast and treated by clearing method. In mature embryo, the procambium was connected with the epicotyl-hypocotyl-radicle axis and cotyledons, whereas protophloem and protoxylem were restricted primarily to the mid-vein and two lateral veins of the cotyledonary base. With the onset of germination, protophloem and protoxylem were differentiated both acropetally and basipetally from the cotyledonary base. The first and second leaf traces appeared in the cotyledonary node, and then differentiated bidirectionally toward the epicotyl and the root tip. The 3rd to 6th leaf traces were connected with the cotyledonary traces in hypocotyl. At the part of the root tip, the xylem was a diarch. As the first and second leaf traces were superimposed at the middle part of the root, the diarch xylem was changed to a tetrarch. As the cotyledonary traces were diverged below the root base, the tetrarch xylem was changed to an octarch. It was suggested that the vascular system of the epicotyl might be superimposed on that of the cotyledon-hypocotyl-root during the formation of the primary vascular system of Prunus davidiana.

• 한국작물학회지
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• 제42권6호
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• pp.841-848
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• 1997

This study was conducted to investigate the inflorescence habit mainly on major in farmer's peanut cultivar of the Shinpung plant type "Daekwang" of sequential branching and the Virginia plant type "Daepung" of alternate branching until maximum flowering dates. All flowers of two pairs of opposite branch in "Daekwang" showed almost symmetrical flowering order and in "Daepung" also showed similar tendency though it had somewhat irregalar alternate branching type in opposite branches. The lowest node in each branch had seven flowers while upper nodes had less flowers in this period. The first flower in "Daekwang" was born at first node of second branch of cotyledonary branches compared to those of "Daepung" at first reproductive branch of cotyledonary branches. One pair of cotyledonary branches had two-thirds of total flowers in two cultivars. Dates of average flower proceeding between nodes in each branch of "Daekwang" were appeared 4.32 days in main axil, 1st and 2nd opposite primary branches were 4.44 and 5.13 days, and 1st and 2nd secondary branches were 5.81 and 6.41 days respectively, but "Daepung" showed similar flower proceeding dates in all branches. but "Daepung" showed similar flower proceeding dates in all branches.