• Korean Journal of Agricultural Science
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• v.15 no.1
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• pp.69-75
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• 1988

This experiment was carried out for the analysis of the ability of callus formation and differentiation in the eight Korean local varieties of adzuki beans (Phaseolus angularis). KLA 102 has the highest ability on the formation of callus (all tissues have 90 % over). Morphological heterogeneity (color and shape) of callus was well reflected to the cell constitution and cell meristematic activities. Meristemoid tissues and rooting were derived from only creamish-white color and soft region of callus.

• Korean Journal of Environmental Agriculture
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• v.13 no.2
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• pp.168-174
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• 1994

The experiments were performed to examine the effects of simulated acid rain (pH 1.0${\sim}$5.0) prepared by mixing sulfuric acid and nitric acid at the ratio of 3 : 1 on germination and growth of seedlings of some floricultural crops. Days to germination showed a one to three days' interval among crops, but pH level did not show any effect on germination for each crop. All seeds used in this experiment did not germinate at pH 1.0. At pH 2.0, the flowering cabbage and geranium still did not germinate, and even though the radicles of seeds were germinated, root hairs did not develop. The length of hypocotyls and radicles appeared to be significantly different according to the pH levels.

• Culinary science and hospitality research
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• v.9 no.2
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• pp.1-10
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• 2003

This study was designed to investigate the effective ratio of bread with Ulmus devidiana. The bread with various contents(0, 10, 20, 30%) of Ulmus devidiana were measured by volume, color difference, texture and sensory evaluation. The results were as follows: The dough yield tended to increase by adding Ulmus devidiana extract but those were not significant difference. The loaf volume index increased by adding Ulmus devidiana extract. The texture(hardness, cohesiveness, springiness, gumminess, chewiness) of bread increased by the addition Ulmus devidiana extract. Color L, a and b value were not significant difference. In sensory evaluation, bread with 10% Ulmus devidiana extract was evaluated as the best in taste, texture, flavor and overall acceptability.

• Korean Journal of Plant Resources
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• v.9 no.1
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• pp.47-54
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• 1996

To search herbicidal compounds in Pulsatilla koreana Nakai, methanol extract of P. koreana roots was purified by sequences of XAD-7 column chromatography, silica gel adsorption column chromatography, silica gel flash column chromatography, preparative layer chromatography and preparative high performance liquid chromatography(Prep, HPLC).The final Prep. HPLC gave two herbicidally-active fractions. These fractions treatment at 100ppm inhibited the root length of Echinochloa crus-galli seedlings by 48% and 60% as compared with the control, respectively. Components in the two active fractions were analyzed by GC-MS Spectrometry. These compounds, which were isolated from P. koreana roots, were identified as several fatty esters, hydrocarbons, squalene, evidonol, and a diazepin analogue.

• Korean Journal of Weed Science
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• v.14 no.3
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• pp.192-198
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• 1994

Zeaenol isolated from the culture filtrate of a fungal weed pathogen Drechslera portulacae, which causes necrosis on the leaves and stem of purslane (Portulaca oleracea). Its structure was determined by single-crystal x-ray diffraction method together with assignments of $^1H$ and $^{13}C$-NMR experiments. Zeaenol inhibited root length of Echinochloa crus-galli and Abutilon avicennae by 22.8% and 54.8% at $3{\times}10^{-6}M$, respectively.

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.3
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• pp.323-329
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• 1989

In the stress analysis of plate, Classical plate theories are generally used. But, in applying these theories the stresses underneath the concentrated load point cannot be analyzed because the solution of stress fails to converge. In this paper, therefore, an attempt is made to analyze the stresses directly underneath the concentrated load point for a supported square plate by using the three dimensional theory of elasticity and the potential theory of displacement on the supposition that uniformly distributed load acts on the central part of it. In order to clarify the validity of the theoretical analysis, experiments for strain are carride out with a square plate. It is shown that these theoretical results are in close agreement with experimental results. Specially, this analysis is in a good agreement with actual phenomenon in case of the thick plate.

• Applied Biological Chemistry
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• v.50 no.4
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• pp.316-320
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• 2007

Three phytotoxic compounds were isolated from the culture broth of Chaetomium sp. through silica gel column chromatography and HPLC (RP-18). Their chemical structures were elucidated as chaetoglobosin F, chaetoglobosin C and chaetoglobosin E on the basis of instrumental analyses such as $^1H-NMR,\;^{13}C-NMR$, and HMQC. They inhibited the root growth of barnyard grass with the $IC_{50}$ values of 66, 65, and $67{\mu}g/ml$, respectively.

• Journal of Life Science
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• v.12 no.6
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• pp.786-795
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• 2002

Three-day-old sunfower(Helianthus annuus L.) seedlings were do-rooted and incubated in the nutrient solutions that contained either deficient or sufficient boron supply, and exposure to various pH and temperatures. In the absence of boron, no adventitious roots were formed in the majority of the seedlings. Boron caused the development of numerous adventitious roots in the lower part of the hypocotyl. The low pH damage was ameliorated by the simultaneous application of calcium, implying the involvement of calcium-requiring process in overcoming proton toxicity. Borate showed a strong ameliorative effect with $Ca^{2+}$. These results suggest that the primary target of proton toxicity may be linked to a disturbance of the stability in the pectic polysaccharide network, where calcium plays a key role in plant roots. Maximum temperature for the growth of adventitious roots was $25^{\circ}C$. Although cessation of growth is the most apparent symptom of boron deficiency, exogenous ascorbate improved adventitious root growth in plants in the absence of boron. From the results it is suggested that the inhibition of adventitious root resulting from boron deficiency, low pH and temperature damage may be a consequence of disrupted ascorbate metabolism.

• Current Research on Agriculture and Life Sciences
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• v.15
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• pp.25-32
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• 1997

This study was carried out to research the biological characteristics among rhizobia and soybean seed and root lectins, and to obtain a basic imformation of host specificity in biological nitrogen symbiosis system. The results obtained were as follows: Purified seed lectin from soybean varieties of paldal, backwoon and hwangkeum formed immunoprecipitin lines with standard soybean seed lectin and the root lectins from soybean seedlings immunoelectrophoretically. Soybean seed and root lectins interacted with Rhizobium japonicum and Bradyrhizobium japonicum, but didn't interacted with Rhizobium. viceae, whereas pea lectin conjugated with R. viceae, but didn't bind with R. japonicum and B. japonicum. Lipopolysaccharides of B. japonicum and R. viceae were fractionated into LPS I and LPS II on the sephadox G-50. Lipopolysaccharides from B. japonicum showed rhe binding acitivity both with soybean seed lectin and root lectin, but those from R. viceae didn't show it with soybean seed and root lectins.

• Journal of Plant Biotechnology
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• v.35 no.1
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• pp.47-53
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• 2008

Effects of growth regulators and culture conditions on seed germination, haustorium development, and callus formation of Korean mistletoe (Viscum album var. coloratum (Kom.) Ohwi) were described. Histological examination showed that seed of V. album contained one or two zygotic embryos with rod shape, and actively dividing cells were mainly distributed in radicle region rather than cotyledon of zygotic embryo. The most significant factor for seed germination and haustorium development of V. album was the requirement of the light. Various growth regulators examined in this study failed to substitute the effect of the light on seed germination. The frequency of callus formation was highest at 27.3% when flower buds were cultured onto B5 medium containing $0.1\;mgl^{-1}$ IAA. Explants from other organs were recalcitrant in forming calluses. Culture conditions described in this study could be applied for production of useful metabolites and multiplication of V. album in future.