• Korean Journal of Plant Tissue Culture
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• v.21 no.6
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• pp.357-362
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• 1994

Chitinases and $\beta$-1,3-glucanases are believed to be important in defending plane against pathogens. Here, we investigated the expression of chitinase(s) in Arabidopsis thaliana cell suspension culture system in response to ethephon (2-chloroethyl phosphonic acid) which produces ethylene or a microbial elicitor, a bacterial pectin-degrading enzyme, $\beta$-1, 4-endopolygalactronic acid Iyase (PGA Iyase), treatment. Chitinase activity was measured either by radio chemical assay using $^3$H-labeled regenerated chitin as substrate or western blot analysis using antibody raised against tobacro chitinase(S). With 1 mg/mL of ethephon or 100 m units/mL of elicitor treatment, maximum levels of activity were reached after 48h. We also investigated distribution of chitinase activity in seedlings, leaves, and root of A. thaliana and found that root have the highest chitinase activity.

• Journal of Ginseng Research
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• v.27 no.4
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• pp.188-194
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• 2003

Rust-spot on North American ginseng roots (Panax quinquefolius L.) is considered a physiological, not a pathological disorder. Ginseng rust-spot starts as an orange spot on the surface of the root and may spread forming a sunken, round to irregular lesion. 5 mm in diameter. Pieces of root, 7 mm in length and containing a rust-spotted lesion, were embedded in agar and sectioned using a vibratome. These sections and hand sections, cut with a two-sided razor blade, were examined using fluorescence microscopy. The 4-5 cell layers of the periderm were destroyed in the area of the lesion and orange substance:, were deposited in and around the lesion. Sections stained with vanillin-HCI and viewed using bright field microscopy confirmed that the orange substances were phenolic compounds. Scanning electron micros-copy showed that the periderm had pulled away from the root, or was completely destroyed, in the area of the lesion. The smooth surface of the lesion indicates the deposition of phenolic compounds in surrounding cells as a wound response. Roots sprayed or dipped in ethephon (1500 mgㆍL$^{-1}$ ) developed rust-spots, more so at 21$\pm$2$^{\circ}C$ than at 3$\pm$0.2$^{\circ}C$. Roots held at 21$\pm$2$^{\circ}C$ were yellowish and developed white cell proliferations. Comparable control roots also developed rust-spots likely due to the high undecomposed organic matter content of the incubation soilless mix.

• Korean Journal of Environmental Agriculture
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• v.30 no.4
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• pp.402-408
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• 2011

BACKGROUND: Effect of various light wavelength and plant defense molecules were evaluated on the hardness and the contents of free amino acid including ${\gamma}$-aminobutyric acid (GABA) in soybean sprouts. METHODS AND RESULTS: Germinating soybean seeds were treated with various single wavelength of light (380, 440, 470, and 660 nm) or without light at $25^{\circ}C$ for six days. Soybean seeds were also treated with stress-signaling molecule ethephon or $H_2O_2$ at the same time. Soybean sprouts treated with 470 nm substantially raised the hardness almost two times than the control. The free amino acid contents were higher in 470 nm and $H_2O_2$ treated soybean seeds than the control. Nutritionally beneficial GABA contents were increased by the treatments of 470 nm, 440 nm, ethephon, and $H_2O_2$. CONCLUSION: These results suggest that the hardness and the contents of amino acids can be regulated by stimuli, which stimuli could be composed of various wavelength and plant defense molecules. Especially, single wavelength 470 nm illumination has the effect of increasing GABA contents with increased hardness.

• Animal cells and systems
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• v.7 no.4
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• pp.337-343
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• 2003

Methyl jasmonate (MeJA) is a signal molecule in the activation of defense responses in plants. In this study, we isolated 15 MeJA-inducible genes by subtractive hybridization. These genes encode two myrosinase-binding proteins, five lipase-like proteins, a polygalacturonase inhibitor, a putative chlorophyll-associated protein, a terpene synthase, a dehydroascorbate reductase, an ascorbate oxidase, a cysteine protease, an O-methyltransferase, and an epithiospecifier protein. Northern analysis showed that most of the Chinese cabbage genes are barely expressed in healthy leaves, but are strongly induced by MeJA treatment. We also examined whether these MeJA-inducible genes were activated by ethethon, BTH, and Pseudomonas syringae pv. tomato (Pst), a nonhost pathogen of Chinese cabbage. The results showed that none of the MeJA-inducible genes was strongly induced by ethephon or by BTH. The genes encoding lipase-like proteins and a myrosinase-binding protein were weakly induced by Pst. Other MeJA-inducible genes were not activated at all by the pathogen.

• Journal of Ginseng Research
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• v.14 no.2
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• pp.122-125
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• 1990

Ethylene was released from leaf and fruit but root of Panax ginseng. Root callus showed higher ethylene release (ER) than fruit ER increased with leaf senesence. Fruit during ripening showed decreasing ER in the order of green stage, early stage of reddening and fully ripened stage. between leaves from the plant with fruits in different stages of ripening showed similar trend of fruit in ER but it was about 10 times higher in leaves than in fruits. Leaves of P. quinquefolius showed about 200 times higher ER than that of P ginseng on 22 July Fruits from the plant treated with ethephon showed higher ER after 109 days. Forty-five day-old seedlings grown with various growth regulators showed a significant decrease of stem length and significant increase of ER only in Uniconazole (0.1 ppm) and H-9 (0.0, 5 ppm) solution.

• The Plant Pathology Journal
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• v.26 no.4
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• pp.402-408
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• 2010

Plant matrix metalloproteases (MMPs) are a family of apoplastic metalloproteases closely related to human matrilysins. Up-regulation of Nicotiana benthamiana matrix metalloprotease 1 (NMMP1) expression by treatment with pathogens, ethephon and aging indicates that the gene is related to plant defense and the aging process through ethylene signaling. NMMP1 expression was higher than in normal growth leaves following infection with an incompatible pathogen Pseudomonas syringae pv. tomato T1 or a compatible pathogen P. syringae pv. tabaci and in aged leaves. Transient overexpression of NMMP1 in N. benthamiana leaves lowered the growth of P. syringae pv. tabaci. However, NMMP1-silenced leaves showed increased growth of P. syringae pv. tabaci. These data strongly suggest that NMMP1 in N. benthamiana is a defense related gene, which is positively regulated by ethylene.

• Korean Journal of Agricultural Science
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• v.9 no.2
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• pp.484-493
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• 1982

This study was conducted to clarify the effects of daminozide (butanedioic acid mono-(2,2 - dimethylhydrazide)) sprayed 2 days be fore harvest and floral preservative solutions on longevity, quality and ethylene production of 'Georgia' cut lily for prolonging vase life and improving quality of cut lily flowers. And also the relation between ethylene production and flower senescence of cut lily was studied. 1. Lilies held in silver nitrate ($AgNO_3$) at 25 and 50 ppm were increased in solution uptake, fresh weight, and flower longevity. The solution of 2.5% sucrose+50 ppm $AgNO_3$+200 ppm aluminum sulfate+10 ppm 6-benzylamino purine prolonged vase life and improved quality of cut lily flowers. 2. Lilies sprayed with 500 ppm daminozide 2 days be fore harvest and then held in the preservative solution (5% sucrose+50 ppm $AgNO_3$+150ppm 8-hydroxyquinoline) after harvest were significantly increased in fresh weight and vase life as compared with non-sprayed (control) flowers. 3. Ethylene production from cut lily was increased by ethephon ((2-chloroethyl) phosphonic acid) treatment. The flowers producing a lot of ethylene, however, were senesced slowly instead of rapid wilting. 4. The preservative solution markedly reduced ethylene production of cut lily but prolonged vase life for only a few days. 5. These results suggest that ethylene be one of the most important factors promoting flower senescence of cut lily, but it be very difficult to prolong vase life remarkably by only inhibition of ethylene production in cut lily.

• Journal of Bio-Environment Control
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• v.28 no.3
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• pp.218-224
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• 2019

This study was conducted to compare the effect of salicylic acid (SA), an ethylene biosynthesis inhibitor, and the 1-methylcyclopropene (1-MCP) fumigation, to prevent fruit quality deterioration and physiological disorders during the shelf-life of Korea's leading export grape variety 'Campbell Early'. The berries treated with SA after 1-MCP fumigation (1-MCP+SA) showed a higher firmness value and titratable acidity than single treatment of SA or 1-MCP. The rate of shattered berry was high as 41.7% for 100ppm ethephon spray, 40.8% for $25{\mu}M$ SA, and 38.2% for 1,000ppb 1-MCP, but showing only 18.7% when the SA was applied after 1-MCP fumigation. The ratio of short brushes less than 1mm was largest at 74.3% for ethephon treatment, while 1-MCP+SA treatment was found to have the longest brush length among all treatments, with a 2-4mm ratio of 22.8% and a 4-6mm ratio of 27.9%. The weight of rachis was found to be the lowest at 2.3g in the ethephon treatment, and the reduction of rachis weight loss per cluster by 1-MCP+SA treatment was evident. In addition, 1-MCP+SA treatment were effective in mitigating stem browning and berry decay during the 16-day storage period at $19^{\circ}C$ in this cultivar, so it is believed that they can be used as a practical post-harvest treatment in grape exportation.

• Korean Journal of Agricultural Science
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• v.18 no.1
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• pp.1-9
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• 1991

This experiment was aimed to develop possible methods to control the maturity of grape berries through the application of exogenous plant growth substances and physical treatments such as defoliation or girdling. 1. Chlormequat and paclobutrazol increased anthocyanin but did not affect soluble solids contents and maturity. Girdling enhanced maturation and solids accumulation whereas defoliation delayed maturity. Solids content of berries in defoliation treatment did not reach to the level of other treatments even when fully ripened. 2. Ripening of grapes is greatly delayed for 20 to 30 days by the application of auxins (2,4-D and fenoprop) compared to the untreated control. Uneven ripening of berries in those clusters was observed when the concentration of auxin was over 50 ppm. Thus, about 30% of berries remained green until the normal berries were overripened. 3. Gibberellin did not affect the maturity of grape berries but maturity was greatly delayed when GA was applied with auxins. Also, uneven coloration between berries was observed such as in the application of auxin alone. 4. Ethephon application combinded with calcium at veraison showed no effect on berry ripening but increased anthocaynin contents. It can be concluded that harvest time of 'Campbell Early' grapes can be effectively extended by delaying the maturity through the application of auxin.

• Korean Journal of Agricultural Science
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• v.7 no.1
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• pp.33-37
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• 1980

To clarify the influence of ethylene on flowering and senescence of carnation flowers and the treatment of the floral preservative solution for reducing their ethylene production, bud-cut carnations (Dianthus caryophyllus L. cv. Coral) were sprayed with/without 500 ppm ethephon [(2-chloroethyl) phosphonic acid] and then held in distilled water or preservative solution (5% sucrose+50 ppm $AgNO_3$+300 ppm 8-hydroxyquinoline). 1. Ethylene inhibited to bloom carnation flowers because of causing sleepiness. 2. Carnation flowers were led to senescence after a lot of ethylene was produced by them. Therefore, ethylene seems to act as a trigger of senescence in carnation flowers. 3. The features of senescence in carnation flowers were different in accordance with the amount of ethylene produced by the flowers. 4. Exposure to ethylene decreased fresh weight, flower diameter, and water uptake of carnations. 5. The floral preservative extended vase life markedly by inhibiting ethylene production of cut flowers. The flowers exposed to lots of ethylene, however, were not restored even though they were held in the preservative solution.