• 통합자연과학논문집
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• 제1권1호
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• pp.24-31
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• 2008

Brassinosteroids (BRs) are a special class of plant steroid hormones that are essential for normal growth and development. Part of confusion is whether BRs are unique to plants, because they have overlapping physiological roles with other better-studied hormones and with physiological responses caused by light. In systems designed to assay for cytokinins, the effects of BRs vary. We measured hypocotyl length for testing the ability of brassinolide (BL) to rescue double mutant between det2 and the photoreceptor null mutant phytochrome B (phyB). PHYB involved in controlling hypocotyl elongation in increased concentration of BL whereas phyBdet2 double mutant just partially rescue to phyB in white and red light indicated the involvement of BRs in PHYB regulated cell elongation. BRs regulated hypocotyl growth was delayed by BAP, a cytokinin treatment but inhibitory effects of BAPs on hypocotyl growth was slightly recovered by BL. The result indicated that the mode of action of BR and cytokinin is independent or sequential in the downstream light-regulated response control on hypocotyl elongation and also light modulated the action of BR and cytokinin in some extent.

• 한국육종학회지
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• 제43권5호
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• pp.442-447
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• 2011

고감미 다수성 계통인 자가수정 스테비아의 hypocotyl 절편체를 이용하여 대량증식방법 개발에 대한 결과는 다음과 같다. 선발된 자가수정개체는 초장이 72.0~120.7 cm로 분포되어 있었고, 분지수는 4.9~56.6개로 분포되어 있었다. HPLC 분석을 통하여 rebaudioside-A(RA)성분이 평균함량 55.2%이상 함유된 자가수정 개체를 선발하였다. 스테비아의 hypocotyl 절편체를 이용하여 MS배지에 1.5 mg/L BA와 0.5 mg/L Kinetin를 혼용 첨가하였을 때 가장 많은 식물체가 재분화되었다. 이는 1개의 절편체가 30개의 식물체 재분화 효율을 나타내었다. 재분화된 신초로부터 발근배지는 0.1 mg/L IBA가 첨가된 배지에서 가장효과가 좋았다. 발근된 신초는 기외 이식 후 순화과정을 통하여 정상적인 식물체로 생육하였다. 본 연구에서 구명된 대량번식방법은 Rebaudioside A 생산성 향상에 효과적으로 이용될 것으로 판단된다.

• 한국자원식물학회지
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• 제17권2호
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• pp.94-101
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• 2004

콩나물의 상품성은 세근의 형성유무 및 형태의 영향을 크게 받는다. 본 연구는 세근발생 억제용 BA의 처리농도에 따른 콩나물의 발아, 생장, 하배축과 뿌리길이 비율을 포함한 형태의 변화를 추적하고자 은하콩, 풍산나물콩, 소원콩 및 준처리를 공시품종으로 증류수, 1,2,4,8 ppm BA 용액에 5시간 침종한 후 6일간 재배하였다. 하배축 길이가 상품으로 출하 가능한 7cm 이상의 비율은 소원콩에서 가장 높고, 준저리는 중간 정도이었던 반면, 상호 비슷한 비율을 보인 은하콩과 풍산콩나물에서 가장 낮았다. 세근의 발생은 풍산나물 콩과 준저리에서 가장 적었고, 4 ppm 이상으로 BA를 처리할 경우 전혀 일어나지 않았다. 하배축 및 뿌리의 길이는 BA 처리농도가 증가할수록 비례하여 감소하였으나, BA처리농도에 관계없이 준저리의 하배축이 가장 길었다. 하배축과 hook 직경은 2∼4 ppm의 BA 처리농도에서 가장 굵고, BA를 처리할 경우 여타 공시품종에 비하여 은하콩과 소원콩이 통통한 것으로 나타났다. 하배축과 전체 생체중도 하배축과 hook 직경과 유사한 경향을 보였다. 뿌리에 대한 하배축 길이의 비율은 BA 처리농도가 증가할수록 비례적으로 증가하였으며, 이러한 비율의 변화를 기초로 시중에 판매중인 콩나물을 조사하여 뿌리에 대한 하배축 길이의 비율을 분석한 바 1∼2 ppm의 BA를 처리한 본 시험 결과의 비율과 유사하였다.

• 원예과학기술지
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• 제30권1호
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• pp.56-63
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• 2012

Tomato hypocotyl can generally be one of two colors, purple or green. Genetically, this trait is controlled by a single dominant gene. Hypocotyl tissue specific color expression is one of many visible genetic marker sources used to select tomato progeny. However, the visible marker does not show a clear distinction between homozygous genotype and heterozygous genotype from the breeding lines. Therefore, to identify a hypocotyl pigmentation related marker, we screened DNA polymorphisms in thirteen tomato lines showing purple or green hypocotyls. The markers used for screening consisted of primer set information obtained from anthocyanin related genes, conserved ortholog set II (COS II) marker sets localized near anthocyanin related genes, and restriction fragment length polymorphism (RFLP) markers localized near COS II markers, which produce polymorphisms between purple and green tomatoes. One primer from a RFLP fragment resulted in a polymorphism on agarose gel electrophoresis. From the RFLP fragment, a cleaved amplified polymorphic sequence (CAPS) marker was developed to distinguish between purple and green hypocotyls. The genotypes of 135 $F_2$ individuals were analyzed using the CAPS marker, and among them, 132 individuals corresponded to the phenotypes of hypocotyl pigmentation.

• Journal of Plant Biology
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• 제32권4호
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• pp.305-312
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• 1989

Developmental anatomy was conducted in order to elucidate the differentiating pattern of fascicular cambial initials in the hypocotyl of Ricinus communis. The homogeneous procambium with relatively short cells in early stage is transformed into a heterogeneous structure with long and short cells in late stage in tangential view. Fusiform and ray initials are gradually originated from the long and short cells of the procambium in hypocotyl in later stage respectively. Fusiform initials are not shorter than procambial cells because of the successive elongation of vascular meristematic cells. Therefore, the distinction between procambium and fascicular cambium is not made from comparison with their cell length. The characteristics of the fascicular cambium are gradully acquired at or just after completion of hypocotyl elongation.

• Journal of Plant Biology
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• 제32권4호
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• pp.323-330
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• 1989

This work was carried out to elucidate effects of endogenous and exogenous IAA transport on adventitious root formation in Phaseolus vulgaris hypocotyl cuttings. For inverted or normal incubation in distilled water, the adventitious root is always formed at the morphological base but not at the morphological apex. For inverted incubation, in both distilled water and certain chemical solution, the root formation is retarded more at the first stage (0-24 hr) than at the second stage (24-48 hr). When p-chlorophenoxyisobutyric acid (PCIB) was applied to the cuttings at the first stage, theroot formation was inhibited more than at the second stage. Treatment of 2,3,5-triiodobenzoic aicd (TIBA)markedly inhibited the adventitious root formation in Phaseolus vulgaris hypocotyl cuttings. This inhibition influenced the root according to the applied stage and period. Therefore, the root formation is more related to the stage of root primordium formation than to the stage of root elongation from the primordium. Inhibition of auxin transport oraction by TIBA or PCIB could also be reversed when hypocotyl cuttings are incubated in exogenously applied IAA solution.

• Journal of Plant Biotechnology
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• 제6권4호
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• pp.253-258
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• 2004

Plant regeneration depending on explant type was inves-tigated with cotyledon, hypocotyl, and leaf explants of garland chrysanthemum (Chrysanthemum coronarium L.) cultured on MS basal medium supplemented with various concentrations of SAP and NAA combination. Among the three different types of explants, hypocotyl explants grown on MS medium containing $1.0{\mu}M\;NAA,\;1.0{\mu}M\;BA\;and\;6{\mu}M\;AgNO_3$ produced the highest adventitious shoots (4.67 per explant). Hypocotyl explants not only produced more vigorous shoots, which regenerated aster than the cotyledon and leaf explants. An efficient root formation was observed in MS medium containing $3\%$sucrose. The concentration of NAA did not show significant effects on root formation. Results from this experiment suggested that hypocotyl explants were efficient for the regeneration of garland chrysanthemum.

• Journal of Plant Biology
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• 제11권1호
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• pp.22-26
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• 1968

Hypocotyl segments of shade-grown soybean sprouts(var. Kumdo) were floated in solutions of various substances at physiological levels and grown for either 24 hours at 28$^{\circ}C$ or 72 hours at $25^{\circ}C$. Increased length of the segments beyond 20mm (the original length) was obtained as a measure of the present studies. At the room temperature, Ca and DNP strongly inhibited elongation of the hypocotyl segments, whereas K, IAA, GA and EDTA in general promoted it. There were, however, no such differences in the effects at relatiely low temperature. This indicated that the elongation process not only involves stretching of wall materials, but also does synthesis of the materials. Ca was found to be antagonistic to the promotive action of GA in the elongation, and the IAA action involves metabolic energy. EDTA seemed to act as a widely known chelator removing Ca already existed in the hypocotyl tissue, thus shwoed a promotion in the elongation.

• 생물환경조절학회지
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• 제16권1호
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• pp.47-53
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• 2007

본 실험은 고품질의 콩나물 생산을 위한 기초연구로서 식물생장조절제를 이용한 세근발생 억제 및 하배축비대촉진을 위한 처리 방법을 구명하고자 실험을 수행하여 다음과 같은 결과를 얻었다. 식물생장조절제 중 $GA_3$나 NAA 처리는 세근발생 억제효과가 미약하였다. 반면 BAP처이믐 세근발생이 전혀 일어나지 않았고 하배축의 비대를 촉진하였는데, 저농도인 $10mg{\cdot}L^{-1}$ 및 $15mg{\cdot}L^{-1}$ 처리에서도 그 효과가 인정되었다. BAP의 처리시간은 짧을수록 하배축 비대가 촉진되었고 하배축 비대를 촉진하는 처리시간은 6시간 처리였다. BAP 처리 후 24시간 간격으로 관수는 세근 발생율이 낮았고 하배축 비대는 촉진되었다. 인돌비는 적정농도로 알려져 있는 4.2%보다 낮은 농도인 1.1%용액을 처리하더라도 세근 발생이 크게 문제되지 않았다.

• 생명과학회지
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• 제11권2호
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• pp.166-172
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• 2001

Various types of the seeding of bottle gourd widely used as a rootstock of watermelon has been required to satisfy the farmers need. The study was done to determine the effect of light quality of blue, red and far-red lights treated with light emitting diodes on growth and morphology of bottle goured seeding and chlorophyll content of its cotyledons. The lights were treated in the growth chamber for 7 days to the seeding elapsed 8 days after sowing under natural condition, and 64 hole trays with commercial bedsoil. Plant height, length and diameter of hypocotyl, leaf area of cotyledon and first true leaf, its leaf length, number of true leaves, fraction and total dry weight were measured. Red light shortened and slenderized the hypocotyl, which lengthened by far-red light and thickened by blue light. Plant height was declined in order of far-red light treatment, blue and red lights mainly due to difference of hypocotyl length, Area and length of the first true leaf became smaller and shorter under far-red light than under the other lights. However, blue light increased leaf area of cotyledons. Two cultivars cv. Yongjadaemok and cv. Kunghap had different response to the light treatments in total seedling dry weight(dw); far-red and red light treatments showed the greatest and the least dw of hypocotyl, respectively, while blue and red lights did the greatest dw of the other organs. Among the ratio of each organ dw to total dw, those of hypocotyl and true leaves were different between the light treatments; the highest ratio of hypocotyl dw to total dw was observed in far-red light treatment but the lowest was in red light treatment. Those of the true leaves were the lowest in far-red light and similar response in blue or red light treatment. Chlorophyll content of cotyledons was decreased in order of red light treatment, blue and far-red lights, meaning that short period light treatment may influence photosynthesis of seeding and afterward its growth.