• Journal of Plant Biology
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• v.26 no.4
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• pp.207-216
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• 1983

Mature embryo and developing seedlings of Ginkgo biloba L. were embedded in a paraplast and serially sectioned at 10${\mu}{\textrm}{m}$ to examine vascular differentiation and vascular transition. Procambium and protophloem formed a continuous system along the epicotylhypocotyl root axis and cotyledons in mature embryo, whereas protoxylem was differentiated discontinuously in the cotyledons and rarely in the upper hypocotyl. The traces of the first and second leaf primordia apeared almost at the same time oppositely to each otehr at the epicotyl and alternately with the cotyledon traces in the upper hypocotyl. The trace differentiated bidirectionally toward the epicotyl and root tips. the young root initially formed a diarch xylem. Then, as the traces of the first and second leaves were superimposed, the diarch xylem. Then, as the traces of the first and second leaves were superimposed, the diarch xylem of the root was changed totriarch and tetrarch xylem, respectively. On the formation of primary vascular system of Ginkgo biloba, it is suggested that the primary phloem forms a continuous system throughout the seedling, whereas the primary xylem of the epicotyl is formed independently from that of the root-hypocotyl cotyledon system.

• Journal of Plant Biology
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• v.36 no.1
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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.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.235-236
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• 2003

섬유의 습식 가공은 에너지 집약적 산업이다. 대부분의 에너지는 가공시 사용된 많은 양의 수분을 증발시키고, 건조하는데 소모되어진다. 따라서 거품가공은 물 소비를 감소시켜 에너지를 절약하고 폐수를 감소시키는데 주된 목적이 있다(1). 거품가공은 직물에 부가된 물의 양을 감소시켜 건조단계에서 상당한 에너지 소비(30~80%)를 감소시키는 것으로 알려져 있고(2~3), 최근에는 낮은 wet pick-up율에 의한 가공제 처리의 성능 및 수지의 가교분포에 대한 효과 등에 관한 많은 연구가 이루어지고 있으나 미흡한 점이 많이 보고되고 있다.(4~7) (중략)

• Journal of Plant Biotechnology
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• v.34 no.3
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• pp.243-251
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• 2007

It has been recently demonstrated the presence of not only $C_{28}-BRs$ biosysnthesis, but also $C_{27}-$ and $C_{29}-BRs$ biosynthesis in plants, suggesting that BRs biosynthesis are complicatedly connected to produce biologically active BR (s). This prompted us to investigation of metabolism of a $C_{29}-BR$, 28-homoCS in seedlings of rice from which $C_{29}-BRs$ such as 28-homoTE and 28-homoTY have been identified. In vitro enzyme conversion study using a crude enzyme solution prepared from rice seedlings revealed that 28-homoCS is converted into both CS and 26-nor-28-homoCS, but their reversed reaction did not occur. This indicated that 28-homoCS is biosynthetically converted into more biologically active $C_{28}-BR$, CS by C-28 demethylation and biodegraded into 26-nor-28-homoCS by C-26 demethylation. Next, bio-conversion of 28-homoCS to 28-homoBL was examined by the same enzyme solution. No 28-homoBL as a metabolite of 28-homoCS was detected, meaning that biosynthetic reaction for 28-homoCS to 28-homoBL is not contained, and main connection of $C_{28}-BRs$ and $C_{29}-BRs$ biosynthesis is between CS and 28-homoCS in the rice seedling. This study is the first demonstrated that $C_{29}-BRs$ and $C_{28}-BRs$ bionsynthetic pathways are connected, and that $C_{29}-BRs$ biosynthetic pathway is an alternative biosynthetic pathway to produce more biologically active $C_{28}-BR$, CS in plant.

• The Korean Journal of Ecology
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• v.26 no.1
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• pp.39-47
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• 2003

The leaf aqueous extracts from five gymnosperms plant were investigated for allelopathy with five Hibiscus syriacus varieties. The leaf aqueous extract of Pinus rigida had the highest total phenolic compound of 2.21mg/L, whereas the soil under Pinus koraiensis canopy had the highest total phenolic compound of 1.38mg/L. Fourteen phenolic compounds were isolated from five gymnosperm plants by HPLC. Among them, phenolic compounds were the highest in P. rigida (320.56 g/mg) with the primary compound 5-sulfosalicylic acid (312.55 g/mg). The correlation between leaf total phenolic compound and pH was not significant, while the total phenolic compound of the leaf extract changed soil pH. The relative seed germination of H. syriacus varieties showed 25% was threshold concentration. The germination rates of varieties were similar to the control group or showed slight stimulation to treatment of P. koraiensis extract. H. syriacus Cambanha was similar to the control group or showed stimulation in all treated groups. H. syriacus Seohohyang showed stimulation in both root and shoot growth compared to the control group. In other varieties except Seohohyang, shoot growth was similar to the control group, while root growth was stimulated in all treated groups. The extracts of tested gymnosperms showed significantly more stimulation to transplanted Seohohyang seedlings, whereas others were similar to control or inhibited in the greenhouse. The dry weight of Seohohyang was greater in all treated groups than the control group, while other varieties were inhibited. All gymnosperm extracts stimulated the chlorophyll contents of Seohohyang and H. syriacus Koyoro but other varieties were not significantly affected. Accordingly, it is suggested that Seohohyang seems the most desirable when planted within these five gymnosperms.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.1
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• pp.84-89
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• 1999

A simple cultivation method using Jew's mallow (Corchorus olitorius L.) was examined to evaluate the biological quality of 72 upland soils collected from greenhouses in Korea. Each soil was mixed with 4-fold volume of sterilized basal soil having no indigenous chemical and physical problems to lessen the chemical and physical variations among original sample soils. This study assumes that the biological characteristics of each mixture 2 weeks after treatment reflect those of individual sample soil prior to treatment. Jew's mallow (Corchorus olitorius L.) was cultivated for 4 weeks in a pot filled with 250g of each experimental soil and the biological quality of each soil was estimated by the aboveground plant growth. The results indicated that microbial floral quality was explicitly deteriorated in 18 soils having EC above or equal to $5dS\;m^{-1}$. However, in soils having EC below $5dS\;m^{-1}$, some showed a sign of deterioration, while others did not. As this simple method is a kind of bioassay, it dose not require the measurements of microbial numbers and activities.

• Korean Journal of Plant Tissue Culture
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• v.25 no.1
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• pp.69-74
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• 1998

The somatic embryos of Daucus carota L. cv. Hongshim developed in MS basal medium far 4 weeks had varied number of cotyledons. Palisade and spongy parenchyma of cotyledon were not clearly discriminated in all seedlings developed from the embryos. No independent existence of collateral vascular bundle was observed in all seedlings with various types of cotyledon ; instead, vascular bundles were either interconnected or partially connected with one another. Most of the cotyledonary bases on hypocotyl showed short cylinder structure which encircle plumule. The vascular tissues of cotyledonary bases and nodes of seedlings with jar-shaped or 1 cotyledon were connected in ring forms, showing the pattern of ectophloic shiphonostele, and similar ring form structure was also found in the vascular arrangement of 5 cotyledon seedlings. The vascular bundles of seedlings with 2, 3 and 4 cotyledons in many cases had independently arranged within the cotyledonary bases and nodes, showing the pattern of eustele. In hypocotyl, tetrarch or hexarch xylems prevailed in seedlings with jar-shaped cotyledon or 1 and 5 cotyledon; tetrarch xylems prevailed in 2 cotyledon seedlings; and triarch xylems prevailed in 3 cotyledon seedlings. In most of seedlings, cortex vascular bundles were dispensed in the region from cotyledonary node to hypocotyl, but double vascular bundles were also observed occasionally. In roots, diarch xylems were observed in most of seedlings with 2 cotyledons, triarch xylems in half of seedlings with 3 cotyledons, and diarch xylems in most of the remaining seedlings with the occasional occurrences of tetrarch xylems.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.1
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• pp.63-67
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• 1987

A laboratory experiment was conducted to find out the concentration of phytotoxin in intensively cultivated hot-pepper, garlic and chinese cabbage, and effects of these phytotoxin to the germination and growth of young hot-pepper plant. Also this experiment presents describes of the bio-assay method and results of phytotoxin application to the toxicity of hot-pepper plant. The results obtained were summarized as follows; 1. A series of non-volatile (aromatic) phenolic compounds such as hydroquinone, benzoic-, p-hydroxybenzoic, and vanillic acid were quantitatively and qualitatively analysed using BSA(N, O-bis(trimethylsilyl)acetamide) by means of gas chromatography method. 2. Phytotoxin as hydroquinone, benzoic-, p-hydroxybenzoic- and vanillic acid were determined in intensively cultivated hot- pepper, garlic and chinese cabbage. Highest concentration of phytotoxin was obtained in hot-pepper cultivated soil. 3. Direct toxic action of the applied phytotoxin to the germination and young hot-pepper plant growth was observed at the levels of 200 ppm. Benzoic acid was obtained the highest toxicity to the young hot-pepper plant growth. 4. Mode of actions of phytotoxins to the young hot-pepper plant growth were observed as stunting of stem elongation, discoloration of leaf and oxygen depletion from consideration as causes of symptom.

• Journal of Plant Biotechnology
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• v.32 no.4
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• pp.293-300
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• 2005

The possible role of nitric oxide (NO)-induced cell division was investigated to explain the physiologycal effects of a NO donor, sodium nitroprusside (SNP) on the growth of primary leaves in chinese cabbage seedling plants. Exogenous treatment of SNP to chinese cabbage plants for 8 days at different concentrations (0, 200, 500 and 1000 ${\mu}M$) affected the leaf growth in a concentration-dependent manner, showing a maximum growth at $200\;{\mu}M$. In accordance with leaf growth responses, the chlorophyll and soluble protein contents increased strongly to 142% and 134% of control at $200\;{\mu}M$ SNP, respectively. However, a very little decrease in chlorophyll and a 13%> decrease in protein were observed at $1000\;{\mu}M$ SNP. In addition, the content of DNA and RNA also increased maximumly to 142% and 139% of the control at $200\;{\mu}M$ SNP, respectively, whereas they decreased to 80% and 84% of the control at $1000\;{\mu}M$ SNP. With respect to the development of enzymes related to cell wall synthesis, $200\;{\mu}M$ SNP led to the maximum activities in both phenylalanine ammonia-lyase (212% of the control) and guaiacol peroxidase (134% of the control). However, the activities of both enzymes were not modified significantly at $1000\;{\mu}M$ SNP. In conclusion, these results suggest that the enhancement of leaf growth in chinese cabbage plants by SNP at the effective concentration was probably due to the NO ability in the induction of cell division.

• The Korean Journal of Ecology
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• v.17 no.1
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• pp.23-35
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• 1994

To investigate phytotoxic substances in Artemisia argyi, the donor plant, and their biological activities, seed germination and seedling growth of receptor plants such as Arundinella hirta, Echinochloa crus-galli, Rumex crispus and Lactuca sativa were examined at different concentrations of aqueous extracts of the donor plant. Germination of four receptor species was inhibited by the extracts, while seedling growth was decreased to a lesser degree than in the germintion test. Germination, seedling growth and dry weight growth of Achyranthes japonica grown in pot were proportionally inhibited by the extracts. Volatile substances emitted from A, argi plant caused slight inhibition in the germination and seedling growth of the receptor species. Essential oil of the plant extracted by Karlsruker's apparatus inhibited growth of microorganisms and callus growth of Pinellia ternata and Oryza sativa. The GC /MS method was employed for analysis and identification of allelochemicals from A. argyi leaves. Sixty-one chemical substances such as a-pinene, camphene, 1. 8-cineol, etc. were identified from essential oil of A. argyi. The results of this experiment on seed germination, seedling growth, microorganism culture and tissue culture indicated that naturally occurring chemical substances from A. argyi would be responsible for the growth inhibition of plants studied.