• Journal of Korea Water Resources Association
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• v.53 no.3
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• pp.167-179
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• 2020

Recently, new levee material has been developed to enhance natural soil strength and vegetation growth using biopolymer. In the study, critical tractive force of vegetated mats mixed with biopolymer mixed soil has been evaluated to apply the mixed soil to levee construction material. The mixed soil has been produced by mixing beta-glucan, clay, and sand. Full scale test bodies have been constructed with 3 cm thick of the mixed soil. Total 4 test bodies have been constructed and experimented. Critical tractive forces have been evaluated by observation and measurement of failure conditions and soil loss. Although performance of the vegetated revetments are affected by vegetation coverage conditions, the critical tractive forces are shown about 40 N/㎡ and the critical velocities are shown about 4 m/sec by full scale experiment. Erosion resistance is also enhanced by combination of root and net with mat materials.

• Korean Journal of Medicinal Crop Science
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• v.14 no.1
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• pp.31-35
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• 2006

A protocol for plant regeneration from hairy root of Rehmannia glutinosa transformed by Agrobacterium rhizogenes ATCC15834 has been developed. Transgenic shoots were regenerated from hairy roots within 6 weeks after culture on the SH medium supplemented with 0.5 mg/l BA. Shoots were rooted on plant growth regulator free SH medium successfully. The transformed plants, which were regenerated from hairy roots, had thiner roots with extensive lateral branches, wrinkled leaves, shorter node, and grew faster compared with non-transformed plants. The biomass of the transformed plant was 1.28 g (F.W) per plant, significantly higher than the non-transformed plant (0.54 g F.W). The catalpol content in the transformed plant (0.56%) was also higher than that of the non-transformed plants (0.43%).

• Korean Journal of Medicinal Crop Science
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• v.14 no.1
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• pp.23-26
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• 2006

One of micropropagation methods was investigated by using a multiple-shoots protocol. Multiple shoot formation was obtained from excised axillary buds of Hypericum erectum on half-strength or basal MS medium supplemented with TDZ or BA. The optimal combination of shoot multiplication for the production of more shoots with a suitable size was MS medium supplemented with $0.005\;mg{\cdot}L^{-1}$ TDZ (6.5 adventitious shoots per node). In vitro rooting was carried on half-strength MS medium with $1\;mg{\cdot}L^{-1}\;GA_3\;and\;0.5\;mg{\cdot}L^{-1}$ IBA treatment. In addition, the rooted cuttings were showed a better root growth in the greenhouse and survived in more than 90%. The results show that the species can be micropropagated effectively by the application of axillary bud culture systems.

• Korean Journal of Weed Science
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• v.15 no.2
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• pp.141-147
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• 1995

Glyphosate(N-[phosphonomethyl]glycine) applied to the assimilate-exporting leaves or sprayed to the whole plants of tomato(Lycopersicon esculentum Mil var. Moneymaker). Glyphosate induced the rapid accumulation of shikimic acid within 24 h. The accumulation of shikimic acid companied with chlorophyll loss in meristematic leaves, i.e. apical leaves. The chlorosis was acropetal in apical region of young growing leaf. The degradation of chlorophyll seems to be a secondary or tertiary effect of glyphosate. However, the level of shikimic acid accumulated was reduced except for roots and apical leaves from 5 days after treatment. The accumulating levels are considerably differed through the applicated regions. The level of shikimic acid is highest at the apical meristem 4 days after the application to 3rd old leaf.

• Journal of Plant Biotechnology
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• v.29 no.1
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• pp.25-29
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• 2002

The study was carried out to establish an efficient protocol for shoot organogenesis and plant regeneration from stem explant cultures of Lycopersicon esculentum cv. Micro-Tom. The regenerated shoots obtained from stem explant cultures on solid MS medium containing the different concentrations of BAP. The highest number of shoots (5.3) per explant and shoot growth (0.7 cm) was obtained on MS medium containing 4.0 mg/L BA. The additions of AgNO$_3$ and putrescine substantially improved the shoot regeneration frequency, at the optimal concentration of 7 mg/L and 50 mg/L respectively. The regenerated shoots (about 1 cm) were normal and could be easily rooted with 0.1 mg/L IBA treatment. The rooted plants were hardened and transferred to vermiculite with a 92% survival rate where they grew normally.

• Korean Journal of Plant Tissue Culture
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• v.27 no.3
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• pp.169-173
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• 2000

A 1,183bp cDNA, AmA1, encoding the seed storage protein of Amaranthus hypochondriacus was isolated by reverse transcriptase-polymerase chain reaction (RT-PCR) and characterized. AmA1 gene was subcloned into plant binary vector under Cauliflower Mosaic Virus (CaMV) 35S promoter and nopaline synthase terminator (3'NOS). The recombinant binary vector was used to transform Nicotiana tabacum using Agrobacterium tumefacien -mediated transformation procedure. Shoots were induced on MS medium with 0.1 mg/L NAA, 1.0 mg/L BA, 100 mg/L kanamycin and 250 mg/L cefotaxime. Transgenic plants were selected on rooting medium based on MS medium containing 200 mg/L kanamycin and 250 mg/L cefotaxime without phytoregulators. The presence of AmA1 gene in the transgenic plants was confirmed by PCR followed by DNA hybridization. The expression of AmA1 gene in the transgenic plant was observed by RT-PCR method.

• Journal of Life Science
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• v.17 no.5 s.85
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• pp.641-645
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• 2007

We conducted a seed germination screening under saline conditions to identify salt tolerance(sto) mutants with ethyl methane sulfonate(EMS) mutagenesis seed pool. During the screening, we identified three mutant lines that seemed to confer elevated salt tolerance in high concentrations of NaCl. At 175 mM NaCl, germination rate of sto42-14 mutant(one of the EMS salt tolerance mutants) was 7-fold higher than that of wild-type plants. Interestingly, sto42-14 mutant exhibited insensitivity to high glucose concentration and growth inhibition to gibberellin. Our results suggest that sto42-14 is involved in salt stress tolerance as well as in glucose and gibberellin response in Arabidopsis.

• Current Research on Agriculture and Life Sciences
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• v.20
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• pp.65-70
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• 2002

This study was conducted to investigate allelopathic potential of various crosses of rice cultivars using their inhibitory effect on barnyardgrass growth under field conditions, and to determine PAL activity and phenolic compounds involved in phenylpropanoid pathway from selected crosses of rice cultivars. Under field conditions, Kouketsumochi, Woo co chin yu possessed higher allelopathic potential inhibiting over 90% of barnyardgrass growth. Crosses of Kouketsumochi/Woo co chin yu, Dongjinbeyo/Kouketsumochi, Dongjinbeyo/Woo co chin yu showed over 80% inhibitory effects on barnyardgrass growth. The highest PAL activity, $63.46{\mu}kats/kg$ proteins was detected in Kouketsumochi which is the most important enzyme in phenylpropanoid pathway and also higher PAL activity in crosses with Kouketsumochi. Content of cinnamate was $2.64{\mu}g/g$ f.w. in Kouketsumochi which was 2 to 5 times higher than other rice cultivars tested, indicating that higher PAL activity resulted in more cinnamate. The similar trends in cinnamate content and PAL activity were observed in crosses of rice cultivars with Kouketsumochi.

• FLOWER RESEARCH JOURNAL
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• v.19 no.1
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• pp.37-41
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• 2011

This experiment was carried out to find an optimum shading level for the growth of root and shoot, and to find the effect of shading level after August on the induction and growth of inflorescence of Phalaenopsis hybrid. The shading levels were 50%, 60%, 70%, 80% and 90% of natural light($1200{\mu}molm^{-2}s^{-1})$. The $CO_2$ uptake, transpiration rate, carbohydrate content, fresh weight and dry weight of Phalaenopsis hybrid were higher at 50-60% level than the others. But, it was diminished when the shading level was increased from 70% to 90%. Inflorescence length, the number of inflorescence and flower per plant all increased under 50-60% shading level and the day needed for the flowering after treatment decreased. Especially, the induction of inflorescence was depressed and flowering is not occurred under 90% during experiment period. These results suggest that the optimal shading level for the growth of Phalaenopsis including inflorescence was founded to be 50-60% in the season of light intensity and amount of sunshine decrease after august.

• Korean Journal of Plant Resources
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• v.13 no.2
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• pp.124-130
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• 2000

In an effort to produce high quality Angelica gigas NAKAI in the southern area of Korea, a variety of mulching materials were used to prevent withering during the summer. The experimental results are summarized as follows. Soil water content and temperature under various mulching materials were higher than those without mulching, in all the cases studied. Among various mulching materials P. E.(polyethylene) mulching material showed the highest effect. The appearance of weeds was the lowest when using the black P. E. mulching, while growth of weeds was the greatest when using transparent mulching. Growth and development of the plant were better with P. E. mulching than straw mulching or no mulching, allowed for more and bigger leaves. The bolting rate was about 2∼5%, with a slightly larger value under P. E. mulching. Under P. E. mulching, probably due to good physical properties of the soil the number of roots was large, and the length and diameter were good. Active growth of roots under P. E. mulching resulted in a yield increase of the plant. The black P. E. mulching material showed a prominent effect on suppression of weed growth, and the black P. E. material was considered to be the most recommendable among various P. E. mulching materials when there is a lack of labor.