• Journal of Biosystems Engineering
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• v.25 no.6
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• pp.511-516
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• 2000

The strength of the connecting joint of boxthorn(Lycium chinense Mill) fruits to tree twigs was determined experimentally at several pulling angles(0$^{\circ}$, 15$^{\circ}$, 30$^{\circ}$,45$^{\circ}$and 60$^{\circ}$) and at different harvesting seasons from August to November 1999 using an universal testing machine. The detachment force of mature fruits of boxthorn decreased as the pulling angle increased and varied with the harvesting season. The detachment force however did not gradually decreased as the harvesting season advanced due to difference of maturity of fruits from one harvesting season to another. Among three varieties of boxthron Cheongyang gugija Cheongyang native and Cheongyang ＃2, the maximum detachment force was 1.24 N at the pulling angle of zero degree. The highest detachment forve(1.29 N) of mature fruits of boxthorn appeared at the harvesting season of August, 1999.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1997.05a
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• pp.1-4
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• 1997

멜론(Cucumis melo L.)은 서아프리카, 중근동, 인도, 중국등이 원산지로 알려져 있으며 유럽형 넷트멜론과 동양계 무넷트멜론으로 크게 분류되고 있다. 우리나라는 삼국시대부터 동양계멜론인 참외가 주로 재배되어 왔으나, 최근 국민소득수준의 향상과 더불어 고급 과채류에 대한 선호도가 높아짐에 따라 넷트 멜론의 재배가 증가되고 있는 추세이다. (중략)

• Horticultural Science & Technology
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• v.17 no.3
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• pp.341-343
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• 1999

Quality of 'Niitaka' pear fruit was evaluated by instrumental and sensory analysis in relation to storability. Fruits harvested at commercial maturity were stored in a common storage room or in a cold storage at $2^{\circ}C$. During storage, fruits were sorted by instrumental measurement of soluble solid content (SSC) and flesh firmness. Then, overall acceptability was evaluated by organoleptic test. Critical storage period was determined by sensory evaluation index for different storage methods. After 60 days of storage, eating quality was acceptable when flesh firmness was higher than $3.3kg/8mm{\emptyset}$. As for soluble solid contents, high eating quality was obtained when pear fruit contained soluble solids higher than $13.0^oBrix$. In 'Niitaka' pears, however, changes in soluble solid content seemed not to be an appropriate parameter to determine storability since SSC increased during both common and cold storage. Data of organoleptic test and postharvest changes in flesh firmness suggested that storability of 'Niitaka' pear fruit seemed to be 30 days in a common storage and 120 days in a refrigerated storage.

• The Plant Pathology Journal
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• v.17 no.5
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• pp.300-304
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• 2001

Apple is the most economically important fruit in Korea. The suspected viroid disease of dapple apple was found in apple fruits cultivated in Kyungpook province. Symptoms begin in mid-July as small circular spots, which stand out against the background color on the young fruit. Dappling of the fruit becomes more intense and easier to detect as the fruit approaches maturity; the affected spots remain yellowish as the fruit matures. no leaf or bark syndromes have been associated with this disease. The infected fruits are downgraded considerably during quality grading. The low molecular weight RNA containing viroid RNA molecules were extracted from the peels of the apples with dapple symptoms. The RNA molecules were extracted from the apples using Qiagen column chromatography. The purified RNAs were used for the synthesis of cDNA with RT-PCR. The PCR products were then ligated into a pGEM-T Easy vector, cloned and sequenced. The sequence of the viroid RNA molecule shows 331 nucleotides with one base difference ("G" insertion between the position of 133 and 134) compared with that of the Apple scar skin viroid (ASSVd) reported by Hashimoto and Koganezawa in Japan. This is the first report on the occurrence of the ASSVd in apple trees cultivated in Korea, as well as the identification of a new Korean strain of the ASSVd.the ASSVd.

• Research in Plant Disease
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• v.8 no.4
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• pp.215-219
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• 2002

Fruit rot of pomegranate (Punica granatum) caused by Coniella granati were observed in several farmer's fields in Gwangdo-myon, Tongyeong City, Gyeongnam Province, Korea. The symptoms occurred on fruit with rotting then eventually dropping and mummification. The colony color of causal fungus was whitish on potato dextrose agar. Conidia were single celled, pale brown or olive in color at maturity, straight or slightly curved fusiform in shape, and were 10.3~17.4$\times$2.8~4.0 ${\mu}{\textrm}{m}$ in size. Conidiogenous cell were hyaline, branched only at the base aseptate, elongate, phialidic, enteroblastic and 12.4~1.4$\times$2.8~3.6 ${\mu}{\textrm}{m}$ in size. Pycnidia were black in color and globose in shape and 124.6~228.4 ${\mu}{\textrm}{m}$ in size. Optimum temperature for mycelial growth was $25^{\circ}C$. On the basis of mycological characteristics and pathogenecity test on host plants, the fungus was identified as Coniella granati. This is the first report on the fruit rot of pomegranate caused by Coniella granati in Korea.

• Journal of Sericultural and Entomological Science
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• v.43 no.2
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• pp.99-103
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• 2001

Daeseongppong, Daebungppong, Daeokppong were bred, and Shingwangppong was selected among the recommended mulberry varieties of the grown silkworm, in order to meet the increasing the interest about the mulberry fruit, The major characteristics of the mulberry fruits were also studies. The chromosome number of Daeseongppong, Daebungppong and Daeokppong are 2n=56 recognized autotetraploid, and that of Shingwangppong is 2n=42 as a triploid. Seed forming rate of Daeseongppong, Daebungppong, and Daeokppong are more than 58%, but that of the Shingwangppong is very low with 6.7%. Concerning the single fruit weight, Daeseongppong is 4.05g, Daeokppong 3.38g, Daebungppong 2.99g which belonged to big fruit group. However Shingwangppong is medium as 2.28g. The sugar contents of Shingwangppong, Daeokppong, Daebungppong, Daeseongppong are 14.8%,13.7%,13.1% and 12.7% respectively. The sugar/acidity rate of them are above 21. The fruit maturity of Shingwangppong is early, those of Daebungppong, Daeokppong are medium and that of Daeseongppong is late. Yielding Potentiality of Daebungppong is high, those of Daeseongppong, Shingwangppong are comparatively high, and that of Daeokppong is moderate. In the case of cold hardiness, those of Shingwangppong, Daeokppong, Daebungppong are comparatively good, that of Daeseongppong is weak slightly.

• Horticultural Science & Technology
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• v.31 no.2
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• pp.135-140
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• 2013

This experiment was conducted to find the effects of a $GA_3$ and thidiazuron (TDZ) on seedless rate, harvest time, fruit cracking and fruit quality in 'Kyoho' grapes over two years from 2008 to 2009. In 2008, fruit clusters were dip treated with $GA_3$ $25.0mg{\cdot}L^{-1}$ twice at full bloom (FB) and 14 days after full bloom (DAFB) in a combination with TDZ 0 or $2.5mg{\cdot}L^{-1}$. Berry seedless rate and berry enlargement were slightly improved only when TDZ was added to the second $GA_3$ treatment at 14 DAFB, compared to $GA_3$ + TDZ treatments at both FB and 14 DAFB. However, berry cracking rate was significantly increased by any plant growth regulator (PGR) treatments compared to non treatment. In 2009, $GA_3$ at $12.5mg{\cdot}L^{-1}$ and $25.0mg{\cdot}L^{-1}$ was dip treated twice at FB and 14 DAFB while TDZ $2.5mg{\cdot}L^{-1}$ was treated only at 14 DAFB. Berry cracking rate was depended on the concentration of $GA_3$ applied. The higher concentration at $25.0mg{\cdot}L^{-1}$ significantly increased berry cracking rate while the lower concentration at $12.5mg{\cdot}L^{-1}$ had no effect. Also, the addition of TDZ to $GA_3$ $25.0mg{\cdot}L^{-1}$ at 14 DAFB, substantially decreased the cracking rate to the level of untreated control. Although all PGR treatments advanced fruit maturity, the most significant advance occurred when TDZ was added to $GA_3$ $12.5mg{\cdot}L^{-1}$ only at the second dip. Considering the overall aspects related to fruit maturity and quality, we concluded that the double applications of $12.5mg{\cdot}L^{-1}$ $GA_3$ at FB and 14 DAFB with addition of $2.5mg{\cdot}L^{-1}$ TDZ only at 14 DAFB was appropriate to produce about 400-500 g size of seedless 'Kyoho' grape cluster having 35-40 berries.

• Horticultural Science & Technology
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• v.29 no.3
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• pp.224-231
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• 2011

Effects of 1-methylcyclopropene (1-MCP) treatment and controlled atmosphere (CA) storage was analyzed for the export quality of 'Fuji' apples after 8-month storage. Apples were harvested from two orchards located in different regions at relatively late stage of maturity for long-term storage. Fruit were treated with 1 ${\mu}L{\cdot}L^{-1}$ 1-MCP and then stored in $0^{\circ}C$ air or CA with 1.5 kPa $O_2$ and < 1.0 kPa $CO_2$ for 8 months. To simulate poststorage export process such as 2-week refrigerated container shipment plus 7-day local distribution, fruit were put in $0^{\circ}C$ air storage for additional two weeks and then on the shelf for 7 days at $20^{\circ}C$. Both the 1-MCP treatment and CA storage reduced respiration and ethylene evolution after storage and shipping simulation, and successfully maintained titratable acidity and flesh firmness even after the export process. In 'Fuji' apples harvested after adequate stage of maturity for long-term storage, however, 1-MCP treatment alone seemed not to be satisfactory for the maintenance of sensorial fruit texture for export market. CA storage or 1-MCP treatment/CA storage combination program should be applied for lately harvested 'Fuji' apples exported after eight months storage.

• Food Science and Preservation
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• v.21 no.4
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• pp.468-472
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• 2014

The effect of pre-storage treatments was investigated to control the occurrence of fruit skin stain in 'Niitaka' pears. The incidence of fruit skin stains was significantly reduced when the fruits were stored in paper bags with a yellow inner color, compared to when they were stored in paper bags with blue and red inner colors. Additionally, the pear fruits that were harvested seven days earlier than their optimum maturity date developed less fruit skin stains in cold storage and retained their quality. Storage in polyethylene (PE) bags did not control the occurrence of fruit skin stains as effectively as did bag-free storage or storage in calcium-coated bags. The dipping of the pear fruits in a chlorine dioxide and calcium solution was highly effective in reducing the fruit skin stains compared to when they were not dipped or when they were dipped only in distilled water. In particular, a 1,500 times diluted solution of sodium dichloroisocyannurate (NaDCC) reduced the incidence of fruit skin stains and the size of the lesions. No stain was observed on the skin of the fruit with a water content lower than 67.7% (w/v) during its storage. In conclusion, packaging pear fruits in bags with an inner calcium coat and dipping them in a chlorine dioxide, calcium, or NaDCC solution can effectively reduce their skin stains during their storage.

• Korean Journal of Agricultural Science
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• v.37 no.2
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• pp.209-216
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• 2010

In order to understand the effects of a single or combined treatments of 1-MCP($1{\mu}L/L$) and $CO_2$(100%) on the firmness of melting type peach fruit(cv. Chunjungdo), fruit were harvested at commercial maturity and examined physiological changes including flesh firmness during 10 days of shelf-life. Firmness loss of fruit was delayed by both single and combined treatments of 1-MCP and $CO_2$. The treatment of 1-MCP was more effective than $CO_2$ treatment but no additive effective on firmness retention was found in the combined treatment. The upsurge of ethylene evolution occurred 5 days of shelf-life in air treated control but ethylene evolution gradually increased in fruit treated by 1-MCP and 1-MCP+$CO_2$. The suppression of ethylene evolution seemed stronger in $CO_2$ treatment. The respiration of fruit significantly inhibited up to 10 days except control where climacteric increase of respiration was found at 10 days of shelf-life. A molecular shift of pectic polymers(an increase of chelator soluble pectins and decrease of water soluble pectins) was induced by both 1-MCP and $CO_2$ treatments. An increase of water soluble pectins was coincident with firmness loss. The delay of firmness loss seemed to be associated with the migration of calcium to wall matrix, especially pectins, resulting in the increase of wall bound calcium. The polygalacturonase activity was significantly reduced by 1-MCP alone 1 day after treatment and increased to similar level of activity 5 days after treatment compared to other treatment except air treated control whereas pectin methylesterase activity seemed not to be affected by both 1-MCP and $CO_2$ treatments. Thus, the molecular shift of pectic polymers appeared not to be related with pectin methylesterase. Further study is required to clarify the softening mechanism associated with molecular shift of pectic polymers and the inter- or intra-cellular movement of calcium ions induced by postharvest treatments of 1-MCP and $CO_2$.