• Korean Journal of Agricultural Science
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• v.18 no.2
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• pp.104-113
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• 1991

This experiment was conducted to find the effect of calcium salts on the inhibition of 'Campbell Early' grape(Vitis labruscana B.) berry absicission induced by ethephon. Ethylene evolution, berry abscission rate, and fruit quality were examined. Several mineral contents were determinded in the berries and morphological changes of cells in abscission zone were also studied. 1. Calcium acetate($4.4-8.8g/{\ell}$) and calcium hydroxide($2.2-8.8g/{\ell}$) completely inhibited berry abscission when applied with ethephon 1,000 ppm while calcium chloride was less effective. 2. Ethylene evolution in the berries treated with ethephon alone reached to maximum peak one day after application. However, that peak in the treatment of ethephon with calcium acetate occurred 3 hours after application. 3. No decrease of ethylene production capacity was observed in the ethephon solution even when held up to 36 hours after preparation but the effect on berry abscission was significantly reduced. In contrast, ethylene production of the solution prepared with calcium acetate was greatly decreased along with the increase of holding time. The effect of calcium acetate in aged solution on the inhibition of berry abscission was not altered. 4. There were no differences in mineral contents such as Ca, Mg, and K between the berries sprayed with ethephon 500 ppm or not. Additional calcium accumulation was not found in the skin, flesh, and petiole of clusters sprayed with 3 kinds of calcium salts (1.5 g net Ca per liter) respectively when analyzed 2 weeks before maturity. 5. Ethephon (1,000 ppm) alone induced the development of abscission layer in petiole but those applied with calcium acetate (0.05 M) did not develop any distinct abscission layer 3days after treatment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.15
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• pp.145-153
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• 1974

Five different levels of Ethephon were treated on tobacco cultivar yellow Special A and Coker and harvested for curing. Changes in dehydration properties, yellowing, chlorophyll, nicotine, sugar and starch contents during the processes of curing were studied in order to justify feasibility of adoption an idea of 3-stage-curing method instead of the 5-stage. Ethephon-treated-tobacco leaves showed marked degradation of chlorophyll, greater dehydration and greater reduction in nicotine contents while little change in either sugar, starch and other chemical components. They showed also shorter hours of curing period allowing possible curing response at a relatively low temperature than those without treatment. Thus they undergo only 3 stages of flue-curing processes, yellowing, calor-fixing and vein-drying, and need 72 hours to finish curing, but the ordinary leaves need 100 hours for it.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.4
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• pp.309-314
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• 1990

A pot experiment was carried out to find the effects of chemicals and its application time on the sterility and other agronomic characters of rice. Two rice cultivars, Samgangbyeo, a Tongil type, and Chuchungbyeo, a japonica type rice were treated with maleic hydrazide (6000ppm), ethephon (6000ppm) and GA3 (10ppm) at five different growth stages. The application times of chemicals were comprised of two different stages of stem elongation and booting and panicle emerging stage. Grain sterility and panicle length were measured for panicles per pot. Culm length was measured for pot basis. MH induced complete grain sterility in rice, but caused severe plant damage (phytotoxicity) ; restricted spike emergence and drying out of plant leaves, sheath and panicles. Ethephon induced 50-60% grain sterility in rice with the least in plant damage. GA3 was not effective in inducing grain sterility in rice, but it increased culm length. The earlier application of chemicals, the higher sterility was induced. Both MH and ethephon reduced culm length and grain yield. Also observed was the varietal response in the occurrence of to chemicals Samgangbyeo showed the higher response to chemicals than Chuchungbyeo.

• Journal of Bio-Environment Control
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• v.7 no.2
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• pp.130-138
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• 1998

This experiment was conducted to study the effect of ethephon(100mg.L$^{-1}$ ) and calcium carbonate (10000mg.L$^{-1}$ ) on the acceleration of peel coloration of ‘Miyagawa Early’ Satsuma Mandarin in the plastic house. The foliar application treatments were conducted once. twice or 3 time at intervals of 15 days from degreening of the fruit apex. Peel coloration of a value by spraying ethephon ＋ clef-non was increased with treatment frequency. The a/b values ran similar to this trend. As a result of this, peel coloration was accelerated by foliar application of ethephon ＋ clef-non. Glucose and fructose did not differ significantly among foliar application frequencies. Sucrose and total sugar increased as foliar application frequency increased, but there was no significant di(ference among foliar application frequency group. The brix values were higher than 12˚BX in all treatments. However, a distinct difference between the control Brix value and the values for the treatment groups was found only in the level 3 frequency group.

• FLOWER RESEARCH JOURNAL
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• v.17 no.4
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• pp.231-236
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• 2009

This study was conducted to identity the effect of plant growth retardants such as paclobutrazol, ethephon, uniconazole and daminozide by drenching on growth of Datura suaveolens 'Orange Star'. Datura suaveolens 'Orange Star' treated with the growth retardants except ethephon was gradually shortened in proportion to the treated concentration of growth retardants. Especially, uniconazole treatment dramatically short ed stem height and width of plant, diminished leaf width and length and also shortened the days to flowering, and increased flowering times per year. On the contrary, ethephon treatment showed the opposite affect such as higher plant width and plant height, increased days to flowering, and decreased the number of flower times. Dwarfing by plant growth retardants in Datura suaveolens 'Orange Star' was effective in orders of uniconazole, daminozide and paclobutrazol.

• Korean Journal of Agricultural Science
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• v.12 no.1
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• pp.1-16
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• 1985

This experiment was conducted to study sex expression and subsequent changes in protein and peroxidase after three cultivars of cucumber plants were treated with ethephon and gibberellin. The three cultivars of cucumber used in this study included 'Sayeup' (monoecious type), 'Sinrokdadaki' (gynoecious type), and 'Seonghowon' (intermediate type). The ethephon at 250 ppm and gibberellin at 100 ppm were treated at the 2-leaf and 4-leaf stages, and subsequent sex expression and changes in protein contents, peroxidase activities and isoperoxidase banding patterns by disc polyacrylamide gel electrophoresis were studied. The results can be summarized as follows: 1. Ethephon treatment slightly increased number of pistillate flowers and significantly decreased number of staminate flowers in the three cultivars, while gibberellin treatment significantly increased number of staminate flowers in both gynoecious 'Sinrokdadaki' and intermediate 'Seonghowon' and did not increase number of staminate flowers in monecious 'Sayeup' 2. There were some differences among three cultivars in protein contents, protein banding and isoperoxidase banding patterns of seeds and germinating seeds. However, it was not obvious to differentiate monoecious from gynoecious cultlvars by these characters. 3. Protein contents in the leaves. and stem apex after ethephon and gibberellin treatment increased gradually at the 2-leaf stage, but decreased at the 4-leaf stage. Protein contents in stem apex at the 4-leaf stage without treatment were much higher in 'Sinrokdadaki' and 'Seonghowon' than in monoecious 'Sayeup'. Protein contents in the stern apex at the 4-leaf stage were increased in the ethephon-treated monoecious 'Sayeup' and decreased in 'Sinrokdadaki' and 'Seonghowon' compared with untreated plants. 4. Peroxidase activities in the leaves and stem apex gradually decreased at the 2- leaf stage, but increased at the 4-leaf stage. Peroxidase activities in stern apex at the 4-leaf stage were significantly increased by ethephon treatment. 5. The number of protein bands in the three cuitivars after treatment gradually decreased in leaves and stem apex at the 2-leaf stage, but increased in the 4-leaf stage. The protein banding pat terns of stern apex of the ethephon-treated monoecious 'Sayeup' at the 4-leaf stage were gradually shifted to the banding.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.757-761
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• 2010

This research was conducted to investigate effect of ethephon on fruit enlargement and coloring of 'Fuyu' persimmon ($Diospyros$ $kaki$). At 7 weeks after ethephon treatment, fruit weight and diameter became significantly heavier and longer in 80 and $100mg{\cdot}L^{-1}$ than the other concentrations of ethephon. Fruit peel hardness decreased with increasing ethephon concentration. The decreased levels were apparent with the treatments beyond $40mg{\cdot}L^{-1}$ at the beginning, and then with those beyond $60mg{\cdot}L^{-1}$. Hunter $a^*$ and $Chroma^*$ of fruit peel treated with ethephon over $20mg{\cdot}L^{-1}$ were significantly higher compared to those with control ($0mg{\cdot}L^{-1}$), but there were no significant differences among those with the ethephon treatments over $20mg{\cdot}L^{-1}$. The increased levels of the $Chroma^*$ were apparent with the treatments beyond $60mg{\cdot}L^{-1}$ at the beginning and then with those of 20 and $40mg{\cdot}L^{-1}$. ${\beta}$-Carotene and lycopene contents of fruit peel were higher with the ethephon treatment beyond $40mg{\cdot}L^{-1}$. Although the ethephon application at 20 and $40mg{\cdot}L^{-1}$ had no effects on fruit enlargement, but fruit coloring was advanced by 2 weeks with the application at $40mg{\cdot}L^{-1}$.

• Journal of Ginseng Research
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• v.29 no.2
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• pp.71-79
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• 2005

In vitro studies using detached inflorescences with peduncles were conducted to investigate flower abscission agents in North American ginseng (Panax quinquefolius L.). Of the nine compounds studied only three, ammonium thiosulphate (ATS), abscisic acid (ABA) and ethephon induced abscission. Anilazine, benzyladenine, carbaryl, gibberellic acid, napthaleneacetic acid and thidiazuron did not induce abscission. ATS dip treatments did not induce abscission but the spray treatments induced $60.5\%$ abscission at $1500\;mg{\cdot}L^{-1}$ and $33.1\%$ at $3000\;mg{\cdot}L^{-1}$. Severe chlorophyll loss occurred on all inflorescences treated with ATS. Both ABA dip treatments and a $250\;{\mu}mol{\cdot}L^{-1}$ spray treatment caused abscission $(40\%)$ without adverse effects, and timing of ABA application was important. Because ABA was only significant in the dip treatments, ABA may not be a practical option for field use on ginseng. Ethephon sprays induced more abscission as the season progressed and as the concentration increased. As the dip concentrations of ethephon increased, the abscission rate decreased and the health of the inflorescences declined. The $1500\;mg{\cdot}L^{-1}$ spray of ethephon gave consistent abscission results over the glowing season with little phytotoxicity. Treatment with the competitive ethylene inhibitor 1-methylcy-clopropene (1-MCP) suggested that flower abscission was due to the liberation of ethylene from the breakdown of ethephon.

• Journal of Microbiology and Biotechnology
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• v.3 no.4
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• pp.238-243
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• 1993

In the suspension cultures of Eschscholtzia californica, phytohormone effects showed that alkaloid production was increased by IAA treatment without kinetin in both volumetric and specific way. Kinetin, however, suppressed alkaloid accumulation. Addition of ethephon inhibited cell growth. However, it enhanced the alkaloid production significantly in both volumetric and specific way. IAA promoted alkaloid production during elicitation. The highest alkaloid accumulation was observed at 5 $\mu$ M of IAA. Ethephon also enhanced alkaloid production during elicitation. The highest alkaloid formation was observed at 460 mg/l of ethephon with elicitation. Elicitation with ethephon, however, altered cell growth and the pattern of benzophenanthridine alkaloids production.

• Korean Journal of Agricultural Science
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• v.40 no.2
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• pp.79-86
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• 2013

We investigate the effect of preharvest spray of aminoethoxyvinylglycine (AVG), an inhibitor of ACC synthase activity, on fruit quality of 'Wonhwang' pear (Pyrus pyrifolia Nakai). And the effects were compared with ethephon which releasing ethylene to elucidate treatment efficacy of ethylene biosynthesis inhibitor on Asian pears. Chemicals were sprayed on 30 days before harvest with AVG (75 and 150 mg/L) and ethephon (100 mg/L), respectively. Highest flesh firmness during 21 days of shelf-life at $25^{\circ}C$ after 30 days of cold storage was attained in the fruit treated with 150 mg/L AVG (26.5N) when compared with untreated control (16.7N), while the fruits treated with 100 mg/L ethephon completely lost their marketability within 14 days of shelf-life by mass drop of firmness down to 11.6N. Low incidence of physiological disorders including pithiness and core browning were attained at the fruits treated with 150 mg/L AVG when we compared with untreated control. No occurrence of mealiness found in the fruits treated with AVG but ethephon treated fruits showed 36.4% during 14 days of shelf-life. Consequently, AVG spray at the concentration of 150mg/L on Asian pear 'Wonhwang' fruit regarded as useful preharvest management approach for keeping quality during marketing period after simulated exportation.