• Journal of Bio-Environment Control
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• v.10 no.2
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• pp.118-119
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• 2001

This experiment was carried out to examine the effects of foliar applications of 100 mg.L$^{-1}$ ethephon mixed with different calcium formulae (10,000 mg.L$^{-1}$ Clef-non, 2,000 mg.L$^{-1}$ Cell-bine, 2,000 mg.L$^{-1}$ Hicalux, and 2,000 mg.L$^{-1}$ calcium acetate monohydrate) on the rind coloration, defoliation and fruit quality of satsuma mandarin cultivated in the plastic greenhouse. Foliar applications of ethephon alone or in mixture with either Clef-non, Cell-bine, Hicalux or calcium acetate monohydrate demonstrated that increased 'a'value of peel chromaticity as compared to the control. The treatments encouraged fruit colour and allowed the harvest date to be predicted. The defoliation ratio decreased considerably by foliar applications of ethephon mixed with Cell-bine or Hicalux. The sugar content of fruit increased by 1.6, 1.54, and 1.54$^{\circ}$Bx with the foliar applications of ethephon, ethephon+Clef-non, and ethephon+Cell-bine, respectively. With the foliar applications of ethephon in mixture with Cell-bine, fruit coloration was accelerated. defoliation was delayed, and fruit quality was improved.

• Korean Journal of Plant Resources
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• v.36 no.5
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• pp.517-526
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• 2023

The harvest time of the late-ripening 'Fuji' apple (Malus × domestica) is variable, depending on the coloration of the fruit skin. Ethephon, a plant growth regulator, promotes the ethylene production and induces physiological responses associated with fruit maturation in climacteric fruit crops, such as apples. This study aimed to investigate the effect of ethephon treatment on fruit characteristics after fruit enlargement, with the objective of proposing an economical and stable harvest control method for 'Fuji'/M.26 apples. Fruit characteristics were assessed at 10-days intervals following the application of 100 mg/L ethephon and mixture of 100 mg/L ethephon and 0.5% CaCl₂ at 145 days after full bloom (DAFB). Starch contents of ethephon-treated (ET) and ethephon with CaCl₂-treated (EC) apples began to decrease from 155 DAFB, and the starch contents of ET and EC at 10 days before harvest were similar to those of control at harvest time. Red coloration of fruit skin in EC was lower compared to ET but higher than control. The average fruit firmness was low in ET, while the control and EC exhibited similar levels of firmness. Fruit sugar acid ratios did not show significant differences between treatments. However, the titratable acidity of EC was significantly lower than that of the control at 10 days before harvest. Moreover, fruit sugar acid ratio of ET and EC at 10 days before harvest in 2021 was similar to their sugar acid ratio at harvest time. Therefore, it was thought that fruit maturation and skin coloration could be accelerated by 10 days from the harvest time through the combined treatment of 100 mg/L ethephon and 0.5% CaCl₂ at the end of fruit enlargement in 'Fuji'/M.26.

• Journal of Plant Biology
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• v.20 no.2
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• pp.77-82
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• 1977

The inhibiotory effect of ethphon on the flowering in Lemna perpusilla 6746 was shown to be related to sucrose concentrations and dilution factors of Hutner's medium. When grown in 1/10-strength Hutner's medium under 10(14) cycles, the plants have been completely inhibited in the floral induction by ethephon (>5ppm) in the presence of sucrose (>20 mM) in the meduim. However, in a less diluted Hutner's medium (1/2-strength), the inhibition of flowering by ethephon was observed to be partially diminished by sucrose at a high concentration (30mM), while a low concentration of sucrose enhanced the inhibitory effect of ethephon in flowering. As inductive dark periodswere extended, the effects of both compounds were partially nullified. Since no significant amount of ethylene possibly released in ethephon decomposition in the medium was detected, the inhibitory effect of ethephon in flowering was postulated to be exerted only through ethylene production within the plants. Plants were incubated in 10 ppm ethephon-containing medium during either dark or light periods, singly or periodically. The most effective single treatment with ethephon was observed during the 4th dark period, when formation of floral stimulus was assumed to be completed beyond a critical level. This postulation can be partially supported by a fact that the plants should be exposed to at least more than four consecutive 10(14) cycles for flowering.

• Korean Journal of Food Science and Technology
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• v.15 no.4
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• pp.409-413
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• 1983

Vitamin and mineral composition of ethephon treated tomatoes were studied, and the results are summarized as follow: 1. Ascorbic acid, carotene (total and beta-carotene), thiamin and riboflavin contents in tomato fruits were not adversely affected by ethephon treatment 1 week before harvest, and these results were consistent for two consecutive years. Riboflavin content of tomatoes in 1979 was significantly higher than that in 1978, and this difference could be due to enviornmental factors. 2. Mineral content in tomato fruits were not significantly affected by ethephon treatment 1 week before harvest. Calcium and manganese contents in treated tomatoes significantly varied from year to year.

• Korean Journal of Agricultural Science
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• v.10 no.1
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• pp.74-83
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• 1983

In order to examine the relationship of fruit abscission and ethylene evolution in 'Jojuro' and 'Imamuraaki' pear trees, the thinning chemicals, ${\beta}$-naphthalene acetic acid (NAA), O, O-dimethyl-O-(3-methyl-4 nitrophenyl) posphorothioate (MEP), 1-naphthyl N-methyl carbamate (carbaryl), and 2-chloroethyl phosphonic acid (ethephon) were applied. Concurrently the effect of calcium acetate on the control of fruit abscission were examined when calcium acetate was added to ethephon and carbaryl. 1. All the applied chemicals (MEP, NAA, carbaryl and ethephon) was effective to abscise fruits in 'Jojuro', and MEP and carbaryl in 'Imamuraaki's. 2. The application of ethephon increased the ethylene evolution but other chemicals did not increase it. 3. There were no significant differences in total sugar contents of fruits by MEP, NAA, carbaryl and ethephon treatments. 4. When the calcium acetate was added to the ethephon and carbaryl, the thinning effects were offsetted. 5. The rate of defoliation due to ethephon treatment was controlled by addition of calcium acetate at 0.1~0.25 M. It was clarified that fruit abscission induced by thinning chemicals except ethephon was not directly related to ethylene production and that degree of fruit thinning can be regulated by addition of calcium acetate to thinning chemicals.

• Journal of agriculture & life science
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• v.44 no.3
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• pp.1-6
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• 2010

The influence of sodium hypochlorite and ethephon on the germination of narrow-leaved purple coneflower (Echinacea angustifolia) was investigated. Treatment of seeds with ethephon (1 mM) for 2 h followed by soaking in 0.525% sodium hypochlorite greatly increased germination (>90%). The treatment of seed with a combination of sodium hypochlorite and ethephon shortened number of days required to reach 50% of the final germination ($T_{50}$) from 4.2 days in control to 1.1 days. Seedlings grown from ethephon-treated seeds had shorter and thicker hypocotyls and roots with higher dry weights compared to the control. The same trend was observed during seedling emergence from soil. Ethephon treatment longer than 2 h resulted in weaker seedlings, probably due to leaf senescence. Anthocyanin content in seedling leaves increased linearly from 0.04 mg/g fresh weight in control to 3.72 mg/g fresh weight in 24 h treatment as the time of seed exposure to ethephon increased. Seed treatment with bleach and ethephon may well be practiced to facilitate the establishment of E. angustifolia in the field.

• Horticultural Science & Technology
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• v.31 no.1
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• pp.38-49
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• 2013

Prohexadione-calcium (Pro-Ca), ethephon and transient water stress were evaluated in a factorial design, as potential inhibitors of early-season shoot growth of high density orchard management of apple (Malus domestica Borkh.) trees. In the experiment, water stress was imposed to one-half of the 7-year-old 'Golden Delicious'/M.9 apple trees in each of 5 blocks, by stopping irrigation for 3 weeks between 35 and 56 days after full bloom (AFB). Within each whole unit, the following Pro-Ca and ethephon treatments were randomly allocated at $2{\times}2$ factorial: a) 0 or 250 $mg{\cdot}L^{-1}$ a.i. Pro-Ca applied at 28 days AFB and b) 0 or 300 $mg{\cdot}L^{-1}$ a.i. ethephon applied twice (35 and 71 days AFB). All trees were hand thinned to king flowers prior to treatments. Vegetative shoot growth was markedly reduced by Pro-Ca, with its effect being obvious within 14 days after application, while ethephon and water stress treatments were less effective. Pro-Ca had no effect on fruit set and yield but slightly increased fruit size. Ethephon substantially reduced the fruit size and yield but had no effect on fruit set. Water stress reduced fruit set, fruit size and yield. With regard to fruit quality, Pro-Ca did not influence fruit shape, flesh firmness and soluble solids contents (SSC) but slightly reduced titratable acidity. Ethephon had no effect on fruit shape but increased firmness, SSC and acidity, while water stress did not influence these fruit quality attributes. Dry weight of dormant spur buds was reduced by both Pro-Ca and water stress, while increased by ethephon. The larger dormant buds led to the larger spur flowers at the tight cluster stage the following spring. Return flowering was promoted only by ethephon, especially on previous season's shoots. There were no significant interactions between Pro-Ca and ethephon or water stress on most variables observed in this study.

• FLOWER RESEARCH JOURNAL
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• v.17 no.4
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• pp.303-307
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• 2009

The purpose of this study was to investigate the effects of ethephon, paclobutrazol, and uniconazole on the flowering of potted Yarrow (Archillea millefolium). Each plant growth regulator was sprayed two times before stem elongation period of yarrow. The tallest was 45.7 cm at $1000mg{\cdot}L^{-1}$ ethephon and the shortest was 11.1 cm at 20 uniconazole. Uniconazole delayed flowering and decreased the number of flowers. Both uniconazole at 20 ppm and paclobutrazol at 200 ppm decreased the number of florets to 90.0% and 43.6% of control, respectively. In ethephon, number of florets was increased 34.1% compared with control. In addition, ethephon and paclobutrazol increased the number of mean auxillaly flowers to 28.6% and 23.5% of control, respectively. On the other hand, uniconazole decrease the number of auxillary flowers to 55.3%. Thus, paclobutrazol was recommended as a suitable plant growth regulator for yarrow pot plant production.

• Korean Journal of Agricultural Science
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• v.21 no.2
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• pp.81-91
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• 1994

This study was conducted to find a potential effect of ethephon or dichlorprop spray on the fruit growth and maturation in 'Niitaka' pears. Chemicals were applied between June 10 to 24 (7-9 weeks after full bloom). Ethephon in the range from 25 ppm to 100 ppm, and dichlorprop from 20 ppm to 40 ppm reduced the fruit size regardless application time and concentration. The fruit growth was more inhibited at the higher concentrations in both chemicals. Flesh firmness was more rapidly decreased in the fruit treated by both chemicals. Firmness at harvest was lowest in the treatment of 100 ppm ethephon. The climacteric increase of ethylene synthesis occurred earlier in the fruit treated by ethephon or dichlorprop regardless application concentrations and the maximum peak of ethylene production was rugher. Total phenolics significantly reduced in fruits treated with ethephon. However, the contents of soluble solids and acid were not affected by ethephon or dichlorprop treatment. Ground color was changed rapidlys by the treatments resulting in the early maturation of fruit. Optimum maturity of fruit was shortened 2-3 days by ethephon and 3-4 days by dichlorporp when maturity was determined on the basis of ground color development and firmness.

• Korean Journal of Food Science and Technology
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• v.7 no.4
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• pp.194-199
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• 1975

The physiological and chemical investigations to explain the after-ripening processes in got green pepper fruit were carried out by treating the fruit with ethephon either alone or with phenylalanine. The studied metabolic changes in fruit during after-ripening period was carbon dioxide and oxygen concentration in interior of the pepper fruit, total carotenoid, ${\beta}-carotene$, total sugar, and free reducing sugar in pepper fruit. These metabolic changes were explained inrelation to the color enhancement judged by the color score to explain the after-ripening processes. Ethephon treatment at 500 ppm significantly accelerated color enhancement as compared to the control and further ethephon treatment increased the number by 20 percent which was not possible in control during same after-ripening period. The oxygen concentration in interior of the pepper fruit during after-ripening period was increased in control when the color score (color enhancement) increased rapidly. However, with ethephon treatment, the oxygen concentration was decreased when the color score increased. Although total and free reducing sugar content were decreased during the after-ripening period total carotenoid and ${\beta}-carotene$ content was increased by 50 and 200 percent, respectively, over control. Also the capsaicin contents was increased by 20 percent by ethephon treatment over control. Although phenylalanine treatment did not affect the capsaicin content, capsaicin content tended to be increased by phenylalanine treatment when treated with ethephon. Acknowledgements: This work was supported by funds from Korean Traders Scholarship Foundation.