• Food Science and Preservation
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• v.4 no.1
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• pp.53-59
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• 1997

Physicochemical properties affecting on the quality of Citrus unshiu Marc. var miyagawa and C. unshiu Marc. var, okitsu according to cultivation area in Cheju were investigated. Linear correlations (r>0.9) were showed between fruit size and peel thickness. There were much difference between cultivation areas in soluble solids of C. unshiu Marc. var. okitsu. The difference were not so much in soluble solids and acid contents of citrus fruits produced at same area below 65mm of fruit diameter, but the quality of large size fruits were inferior. Brix/Acid ratio could not be index for quality evaluation, because of individual deviation. Soluble solid content of citrus fruits produced in south Cheju was higher than that produced in north Cheju. Acid content and Brix/Acid ratio of citrus fruits produced in south Cheju was lower than that produced in north Cheju. The quality of C. unshiu Marc. var. miyagawa clad not so much difference between cultivation area, but the difference of quality were recognized significantly in C. unshiu Marc. var. okitsu.

• Journal of Bio-Environment Control
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• v.32 no.4
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• pp.475-483
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• 2023

This study was conducted to determine the optimal irrigation starting point by analyzing tree growth, physiological responses, fruit quality, and productivity in peach orchards. Seven-year-old 'Kawanakajima Hakuto' peach trees were used in an experimental field (35°49'30.4"N, 127°01'33.2"E) located within the National Institute of Horticultural and Herbal Science located in Wanju-gun, Jeollabuk-do. The irrigation starting point was set with four levels of -20, -40, -60, and -80 kPa from June to September 2022. While there were no significant differences in increase of trunk cross-section area and leaf area among treatments, shoot length and diameter decreased in the -80 kPa and -20 kPa treatments. The photosynthetic rate measured in August was highest for -60 kPa (17.7 μmol·m^-2·s^-1), followed by -40 kPa (15.6 μmol·m^-2·s^-1), -20 kPa (14.5 μmol·m^-2·s^-1) and -80 kPa (14.0 μmol·m^-2·s^-1). SPAD value measured in May and August was lower in the -80 kPa and -20 kPa treatments than in the -60 kPa and -40 kPa treatments. The harvest date reached three days earlier in the -20 kPa treatment compared to other treatments. The fruit weight was highest in the -60 kPa (379.1 g), followed by -40 kPa (344.0 g), -80 kPa (321.0 g) and -20 kPa (274.9 g). Firmness was the lowest in the -20 kPa treatment. The soluble solid content was highest in the -60 kPa treatment (13.3°Bx).The ratio of marketable fruits was highest in the -60 kPa treatment (50.7%) and lowest in the -80 kPa treatment (23.4%). In conclusion, we suggest that setting the irrigation starting point at -60 kPa could improve the fruit quality and yield in peach orchards.

• The Korean Journal of Community Living Science
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• v.20 no.1
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• pp.61-69
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• 2009

This study was conducted to examine the chemical composition of kiwifruit skin, and to est its anti-microbial activities and cytotoxicities, thus, exploring ways for the economic utilization of kiwifruit skin. Four varieties of kiwifruit were examined: Daeheung, Bidan, Haegeum No.1 and Hayward. Vitamin C content in the fruit skins of Bidan, Daeheung, Haegeum No.1 and Hayward were 72.44, 67.22, 62.51 and 61.44mg/100g, respectively. Total amino acids content in the fruit skins of Bidan, Haegeum No.1, Hayward and Daeheung ere 808.31, 706.02, 629.07 and 464.83mg/100g dry weight, respectively. K and Ca content ere $17.20-45.70{\mu}g/mL$ and $4.58-10.15{\mu}g/mL$. While, other inorganic matter contents were below $4.89{\mu}g/mL$. Anti-microbial activity of kiwifruit skin extracts, in terms of the diameter of inhibition zone when tested against five gram positive and three gram negative microbial trains (even in the concentration of 2,000mg/L), was less than 14.1mm. The hyperplasia inhibition of lung cancer cells by methanol extracts from Bidan and Haegeum No.1 using concentrations of 800mg/L were 27.7% and 14.5%, however, those from Daeheung and Hayward were below 3% Consequently, it will be useful to know that kiwifruit skin can be added to processed goods which demand for higher concentrations of vitamin C, amino acids, K and Ca.

• Journal of Ginseng Research
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• v.3 no.2
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• pp.105-112
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• 1979

Effect of gibberllin on the breaking of bud dormancy of root and growth of aerial parts were investigated under laboratory and field condition for the prolongation of shoot growth duration, shortening of fruit bearing age and the increase of root yield. Drop application of GA (0.5ml of 50ppm) on rhizome of one year old root broke bud dormancy better than by low temperature. Soaking for one hour of one year old roots which wintered in the field in GA (50-200ppm) greatly accelerated the emergence of new buds while kinetin was only effective at low level (50ppm). GA substantially increased stem length in early stage and petiole length later on while kinetin increased stem diameter. Under the field condition with polythylene film tunnel (PET) in early spring the soaking in GA (50ppm for 1 hour) of rhizome of 4 year old root with replanting and dropping GA (50ppm, 1ml) on rhizome without replanting brought earlier emergence (29days) in comparison with that in the usual field. PET alone caused 14 day-early emergence. GA increased the length of stem and petiole only in early stage and replanting decreased only petiole length in later stage. Soaking in GA with replanting caused the Pronounced decrease in peduncle length, percentage of (ruin set and dry weight of reproductive organ (fruits and peduncle). Dropping without replanting showed significant decrease only in dry weight of reproductive organ. Fruit maturing was 20 days earlier than in usual held with little difference between GA and PET. It is well expected that GA could be used for early emergence of bud, shortening of root dormancy period, thinning of fruit and higher root yield according to application amount and methods.

• Research in Plant Disease
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• v.14 no.2
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• pp.134-137
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• 2008

A strain of Cucumber mosaic virus(CMV) was isolated newly from sweet pepper(Capsicum annuum var. angulosum) showing necrosis with large necrotic spots on fruits and vein banding with malformation on leaf at Cheongdo area in Gyeongsangbukdo. The new strain was designated as a CMV-NP and the shape of virus particles was isometric of 26 nm in diameter from the sweet pepper fruit by Dip method. The strain of CMV-NP was identified genetically by VC/RT-PCR. CMV-NP could infect systemically on the 9 indicator plants including Cucumis sativus, but it could infect locally on Chenopodim amaranticolor and C. quinoa. CMV-NP induced the specific symptoms of necrotic rings on the inoculated and the upper leaves of N. rustica and Tetragonia expansa. On Cucumis sativus, the large chlorotic ring and vein chlorosis were produced on the upper leaves. CMV-NP had no virulence on Datura stramonium.

• Korean Journal of Plant Resources
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• v.8 no.3
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• pp.265-274
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• 1995

Characteristics of vegetative spur leaf, spur bud, fruiting supr leaf and flowering in relation to canopy position was investigated on order to promote better spur bud and flower bud differentiation on Citrus junos. There was no difference in vegetative spur leaf characteristics among directions. Vegetative spur leaf number and leaf area showed no difference between top and bottom position. There was no difference in spur bud size among directions, but spur bud at top was larger than that at bottom. Specific leaf weight of vegetative spur was mostly influenced by light interception, and leaf dry weight per spur average leaf dry weight, spur bud length and diameter had also a very high correlation with light interception rate. Shading and GA treatment in spur bud and flower bud differentiation was ineffective than natural light. Fruit thinning enhanced fruit quality as well as flower bud differentiation through an increase of leaf number per fruit, over 40 in Citrus junos.

• Horticultural Science & Technology
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• v.32 no.6
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• pp.781-787
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• 2014

The effects of elevated temperature and $CO_2$ concentration on vine growth and characteristics of fruits of three-year-old 'Campbell Early' grapevine were investigated. The treatment groups consisted of a control group (ambient temperature and $390{\mu}L{\cdot}L^{-1}\;CO_2$), an elevated temperature group (ambient temperature + $4.0^{\circ}C$ and $390{\mu}L{\cdot}L^{-1}\;CO_2$), an elevated $CO_2$ group (ambient temperature and $700{\mu}L{\cdot}L^{-1}\;CO_2$), and an elevated $CO_2$/temperature group (ambient temperature + $4.0^{\circ}C$ and $700{\mu}L{\cdot}L^{-1}\;CO_2$). The average shoot length was 312.6 cm in the elevated $CO_2$/temperature group, which was higher than the other groups; with 206.2 cm in the control group and 255.6 cm and 224.8 cm in the elevated temperature group and elevated $CO_2$ group respectively. However, the shoot diameter showed a tendency of decreasing in the elevated temperature and elevated $CO_2$/temperature groups. The equatorial diameter of berries was increased in the higher carbon dioxide concentration, and the soluble solid content was the highest in the elevated $CO_2$ group, with $14.6^{\circ}Brix$ among all treatment groups and the lowest in the elevated temperature group ($13.9^{\circ}Brix$). The harvest date was approximately 11 d earlier in the elevated $CO_2$/temperature group and 4 to 2 days earlier in the elevated $CO_2$ group and elevated temperature group, respectively. Regarding the rate of photosynthesis and transpiration during the growth period, higher photosynthetic rates were observed in the elevated $CO_2$ group and the elevated $CO_2$/temperature group during the early stage of growth; however the photosynthetic rate was reduced dramatically in summer, which was contrary to transpiration.

• Journal of Environmental Science International
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• v.26 no.3
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• pp.381-392
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• 2017

The present study aimed to investigate the effects of low temperature on the growth, yield, quality, and biologically active compounds of strawberry and obtain basic information for developing a technology for stable growth of strawberry in greenhouses. Growth of strawberry, including leaf number, area, and length, plant height, and dry weight was better at the optimum growth temperature of $20^{\circ}C$ than at a lower temperature of $15^{\circ}C$. At the low temperature of $15^{\circ}C$, the cultivar 'Maehyang' was more tolerant and displayed better growth rate than 'Seolhyang'. At $15^{\circ}C$, the fruit production per week and fruit weight was lower than that at $20^{\circ}C$. In contrast, fruit length and diameter were not significantly different between the two growth temperatures. Growth temperature also did not affect the fruit color index, Hunter L, a, b value, or fruit firmness. However, the sugar content of strawberries grown at $15^{\circ}C$ was higher by 0.8 and 1.5 Brix for 'Seolhyang' and 'Maehyang', respectively, than of those grown at $20^{\circ}C$. There was no difference in the content of fisetin, a biologically active compound, for 'Seolhyang' at both growth temperatures, however, the fisetin content of 'Maehyang' was higher at $20^{\circ}C$ than at $15^{\circ}C$. Cinchonine and ellagic acid content of 'Seolhyang' was higher at $20^{\circ}C$ than at $15^{\circ}C$, whereas that of 'Maehyang' was higher at $15^{\circ}C$ than at $20^{\circ}C$. Quercetin content showed no significant differences with respect to growth temperature, however, it tended to increase at $20^{\circ}C$. The cinnamic acid content of 'Seolhyang' was higher at $15^{\circ}C$ than at $20^{\circ}C$, whereas that of 'Maehyang' increased at $20^{\circ}C$. Collectively, the biologically active compounds of strawberry were affected by growth temperature. Moreover, the content of these compounds tended to increase at $20^{\circ}C$, the optimum growth temperature, rather than at the sub-optimal growth temperature of $15^{\circ}C$.

• Journal of Bio-Environment Control
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• v.1 no.2
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• pp.169-174
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• 1992

This experiment was carried out to investigate the possibility of practical use of intermittent soaking system(ISS) in hydroponicaly growing tomato. There were four treatments which were NFT, Aeroponics, and ISS with 10 and 15 minute soaking intervals. 1. Plant height is highest in NFT, but main root length is longest in ISS. While stem diameter and leaf number were not significantly difference. 2. Fresh and dry weight were heavier in NFT than those of other systems at early growth stage, but the heavier in ISS system, the growth more develop. 3. In 43 days after treatment, the number of flowerlet was largest in aeroponics, and then ISS and NFT in order. Fruit weight per plant was also heaviest in aeroponics. 4. Average yield per plant were 1929.1g in aeroponics, 1475.2g in ISS with 10 minute soaking interval, 1276.2g in NFT and 1084.8g in ISS with 15 minute soaking interval. 5. Average fruit number per plant were 11.0 in aeroponics, 9.7 in NFT, 8.3 in ISS with 15 minute soaking interval, and 7.7 in ISS with 10 minute soaking interval. Average fruit weight were 192.9g in aeroponics, 172.4g in ISS with 10 minute soaking interval, 134.0g in NFT and 126.0g in ISS with 15 minute soaking interval. 6. Average fruit length was longer in aeroponics and ISS with 10 minute soaking interval than in the NFT and ISS with 15 minute soaking interval. Average fruit width was similarly wider in NFT, aeroponics and ISS with 10 minute soaking interval than in ISS with 15 minute soaking interval.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.19 no.1
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• pp.7-10
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• 2013

A packaging system integrated in primary and secondary packages to deliver consumers fresh peach in the produce supply chain was designed and its effectiveness on quality preservation was tested. The master packaging system was designed to contain 6 individual polypropylene film (PP, $30{\mu}m$ thickness) packages of 300 g peach fruit inside $35{\mu}m$ thick low density polyethylene (LDPE) bag located in a corrugated paperboard box. As a variable to attain the desired package atmosphere around the fruit during cold storage and subsequent retail display at higher temperature, different numbers (1, 3 and 7) of microperforations in $59{\mu}m$ diameter were tested on the individual PP packages. As control treatment, six fruits were placed without wrapping in a corrugated paperboard box. During the storage at $5^{\circ}C$, the control and individual packages were periodically separated from the box or master package, moved to the simulated retail shelf conditions of $20^{\circ}C$ and then stored for 3 more days with package atmosphere and fruit quality being measured. The package with 7 microperforations was the best in the ability to attain beneficial MA of 6~10% $O_2$ and 11~19% $CO_2$ around the fruit during the chilled storage at $5^{\circ}C$ and simulated retail display at $20^{\circ}C$. Packages with smaller number of microperforations resulted in anaerobic atmosphere at the low temperature storage and/or the subsequent high temperature display. Compared to control, all the treatments with master packaging system gave better retention of fruit firmness with significantly less weight loss.