• Korean Journal of Medicinal Crop Science
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• v.4 no.1
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• pp.64-67
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• 1996

This experiment was carried out to obtain the information on seed dormancy, germinability during storage in wasabia japonica Matsum. $GA_3$ 100ppm+BA 10ppm was more effective than $GA_3$100ppm alone in breaking the dormancy. Storage of seeds pretreated with growth retardants (CCC, Uniconazol) seemed to be a useful method for preventing germination during storage. The stratification was an effective storage method to germinate the seeds for sowing them in fall.

• Korean Journal of Weed Science
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• v.12 no.1
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• pp.39-45
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• 1992

This experiment was conducted to evaluate the effect of gibberellin biosynthesis retardants as used by rice lodging inhibitors on the gibberellin antagonism, auxin interation, ethylene evolution and growth of second crops. Results obtained can be summarized as follows. Inabenfide, paclobutrazol and uniconazole markedly inhibited the epicotyl elongation of mung bean. Inhibiting effect of epicotyl by these chemicals was markedly stimulated by gibberellic acid, thus showing clear antagonism between these chemicals and gibberellic acid. Significantly large number of roots were formed in the mung bean cuttings which were rooted in the paclobutrazol and uniconazol of 1 ppm. The higher the concentration, the more the number of roots forms. It was guessed that these effect was closely related with auxin. Ethylene evolution was a little stimulated in the leaf of rice under the treatment of inabenfide, paclobutrazol and uniconazole at earlier stage(5 DAT), however it was suppressed at later stage(10, 30 DAT) at higher concentration. The effect of gibberllin biosynthesis inhibitors to second crops retarded tomato plants without influencing the height of barley. The treatment of paclobutrazol and uniconazol which is triazole-type more severely inhibited than that of inabenfide which is isonicotinanilide-type. The more the concentration, the less the height of tomato plants.

• Fire Science and Engineering
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• v.33 no.2
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• pp.9-19
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• 2019

Experiments on the combustion characteristics of untreated wood specimens and those treated with four types of silicone compounds were carried out using a cone calorimeter according to the ISO 5660-1 standard. 3-Aminopropyltrimethoxysilane (APTMS), 3-(2-aminoethylamino) propylmethyldimethoxysilane (AEAPMDMS), and 3-(2-aminoethylamino) propyltrimethoxysilane (AEAPTMS) were used as the silane compounds. The flame retardants were synthesized with sodium silicate and amino silane compounds. The measured time to ignition after combustion at an external heat flux of $50kW/m^2$ was 9 s to 11 s. Time to ignition was marked with a delayed value in the 3 s to 5 s range. The peak heat release rate ($HRR_{peak}$) was reduced by 5 to 20% compared with the uncoated specimen, and AEAPMDMS showed the highest initial fire risk. The total heat release (THR) was decreased by 1 to 22%. Compared to the untreated specimen, the fire performance index (FPI) of the specimens coated with silicone sol compounds increased by 1.5 to 2.2 fold. The fire growth index (FGI) of the AEAPMDMS specimen was increased by 30% and the others were decreased by 93 to 94%. Therefore, the fire risk of wood coated with silicone compounds was improved in terms of the heat risk properties.

• Journal of Life Science
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• v.32 no.1
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• pp.70-77
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• 2022

Endocrine disrupting chemicals (EDCs) have been attracting significant attention in modern society, owing to the increased incidence rate of various diseases along with population growth. EDCs are found in many commercial products, including some plastic bottles and containers, detergents, liners of metal food cans, flame retardants, food, toys, cosmetics, and pesticides. EDCs have a hormonal effect on the human body, which disrupts the endocrine system, notably affecting sexual differentiation and normal reproduction, and can trigger cancer as well. Recently, the association between neurological diseases and EDCs has become a hot topic of research in the field of neuroscience. Considering that EDCs negatively affect not only neuronal proliferation and neurotransmission but also the formation of the neuronal networks, EDCs may induce neurodevelopmental disorders, such as autism spectrum disorders and attention-deficit/hyperactivity disorder as well as neurodegenerative diseases, including Parkinson's disease and Alzheimer's disease. In light of these potentially deleterious outcomes, important efforts have been underway to minimize the exposure to EDCs through appropriate regulations and policies around the world, but chemicals that have not yet been associated with endocrine disrupting properties are still in wide use. Therefore, more epidemiological investigations and research are needed to fully understand the effects of EDCs on the nervous system.

• Horticultural Science & Technology
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• v.29 no.3
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• pp.165-171
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• 2011

Plant growth retardants reduce the plant height by inhibiting stem elongation in Lilium davuricum. To investigate the plant hormones related to stem elongation, we sprayed 50 $mg{\cdot}L^{-1}$ diniconazole to young plants of L. davuricum and quantified the contents of endogenous gibberellic acids (GA) and abscisic acid (ABA). In GA biosynthesis, L. davuricum had not only the early C-13 hydroxylation ($GA_{19}{\rightarrow}GA_{20}{\rightarrow}GA_1$) pathway resulting in $GA_1$ as the active form but also the non C-13 hydroxylation (NCH, $GA_{12}{\rightarrow}GA_{24}{\rightarrow}GA_9{\rightarrow}GA_4$) with $GA_4$ as the active form. However, the main pathway was NCH because $GA_4$ concentration of 55 $ng{\cdot}g^{-1}$ dry wt was much higher than $GA_1$ content of 0.23 $ng{\cdot}g^{-1}$ dry wt in control plant. Diniconazole inhibited GA biosynthesis through NCH pathway from its early stage. $GA_{12}$ content decreased by diniconazole up to 6% level of that of control and this effect continued to $GA_4$. Diniconazole reduced $GA_{12}$ content by 12.7 $ng{\cdot}g^{-1}$ dry wt, whereas that of control plant was 213.8 $ng{\cdot}g^{-1}$ dry wt. ABA content decreased up to one third of control by diniconazole application. From the contents of endogenous $GA_4$, $GA_1$, and ABA in this study, we could conclude that diniconazole reduces the plant height by inhibiting $GA_4$ biosynthesis in L. davuricum.