• Journal of Bio-Environment Control
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• v.10 no.2
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• pp.111-117
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• 2001

This experiment was conducted to elucidate the effects of foliar application of monopotassium phosphate on the acceleration of ind color and fruit quality of Satsuma mandarin cultivated in the plastic greenhouse. The 'a'value of peel chromaticity increased seasonably with the increasing frequency of foliar application of monopotassium phosphate, but became gradually irresponsive as the fruit approached to harvesting time. Glucose content increased with the number of foliar applications so did the fructose content. Content of reducing sugars tended to increase with the number of foliar applications by 0.32 to 0.41%.mL$^{-1}$ juice in treatment sof ive or more applications. Sucrose content increased gradually with the increasing number of foliar applications, but there was no significatn difference among treatments. Total sugar also increased with the increasing number of foliar applications Generally, the soluble solid level is considered to be representative of fruit quality. Sugar content increased with the number of foliar application up to 5 times in which sugar content increased by 0.93$^{\circ}$Bx as compared to the control. The fruit acidity of the treatment plots decreased as compared to that of the control, but there was no significant difference in fruit acidity among foliar application times.

• Korean Journal of Plant Resources
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• v.36 no.5
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• pp.490-495
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• 2023

This study was conducted to investigate the growth and fruit characteristics of recently introduced or bred varieties in Korea and to review domestic adaptability. As for the sprouting rate among cultivars, 'Stella' was the highest at 91.6%, followed by 'My Heart' (78.3%), 'IFG-6' (77.3%), and 'Hongju Seedless' (73.2%). As for the flower incidence rate by cultivar, 'Stella' was the highest at 113.5%, and 'IFG-6' had a lower flower incidence at 45.3% compared to other cultivars. The diameter of shoots was less than 11.0 mm in the other three cultivars except for 'Hongju Seedless', and 'Hongju Seedless' was the thickest at 12.5 mm and 'Stella' was the thinnest at 9.6 mm. The berry weight of 'My Heart' was 11.3 g, heavier than other cultivars, followed by 'Stella', 'IFG-6' and 'Hongju Seedless'. Soluble sugar content at harvest time by cultivar was about 19.0°Bx or higher, with 'IFG-6' having the highest level of 20.2°Bx, followed by 'My Heart', 'Stella', and 'Hongju Seedless'. Acidity was the lowest in 'My Heart' at 0.39%, followed by 'IFG-6', 'Stella' and 'Hongju Seedless'. As for the coloring, in the case of 'My Heart', the skin color did not change to red even after the harvest season, therefore the grapes were irregularly colored, so it was judged that the development of cultivation technology to enhance the coloring was necessary.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.186.2-187
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• 2003

에틸렌 작용억제제인 1-MCP(1-methylcyclopropene) 처리에 따른 토마토의 선도연장효과를 검정하기 위해 본 연구는 수행되었다. 토마토“슈퍼도태랑(Supermomotaro)”품종을 Mature green 단계에서 수화한 다음 1-MCP를 2$0^{\circ}C$에서 250, 500, 및 1000ppb 의 농도로 4시간 동안 처리후 온도 2$0^{\circ}C$, 90% RH 조건에 저장하면서 에틸렌 발생, 호흡량 및 품질특성 변화를 조사하였다. 토마토의 에틸렌 발생은 모든 처리구에서 저장 2일째 급등하는 경향을 보였는데, 1-MCP 처리구는 무처리에 비해 그 급등정도가 낮았으며, 호흡량 또한 1-MCP 처리에 의해 효과적으로 억제되었다. 특히 처리 2일 후부터 무처리에 비해 2배정도 낮은 호흡량을 나타냈다. 과피의 착색진행 정도를 Hunter color의 적색도“a”값으로 비교한 결과, 무처리는 2일부터 6일까지 빠르게 증가하였지만 1-MCP 처리구는 그 증가 속도가 낮았으며, 처리농도가 높을수록“a”값의 변화가 적은 경향을 보였다. 또한 황색도“b”값의 비교에 있어서도 1-MCP 처리구가 무처리에 비해 그 변화가 적었다. 경도는 무처리에서 2일 후에 급격히 감소하는데 비해 1-MCP처리에서는 4일까지 그 감소 폭이 적었으며, 1-MCP처리 농도별 차이는 크지 않았다. 부패과 발생은 무처리와 500ppb 처리에서 비슷한 수준이었으며, 1000ppb 처리에서는 오히려 무처리에 비해 부패율이 높아 고농도 처리에 의한 장해로 판단되었다. 그러나 250ppb 처리는 무처리에 비해 부패율이 적게 나타났다.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.306-312
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• 1998

Free sugar, organic acid, naringin, hesperidin and inorganic elements change of six varities of Cheju citrus fruits; Citrus natsudaidai, C. grandis, C. platymamma., C. sudachi, C. aurantiun and C. unshiu Marc. var. miyagawa by harvest date were investigated. Changes in free sugar of citrus fruits on the different harvesting stages and varieties showed a little differencies. The content of sucrose, glucose and maltose in citrus juice were $44.9{\sim}66.0%,\;15.7{\sim}25.7%\;and\;17.5{\sim}30.1%$, respectively. As the fruits were matured, free sugar was increased, but organic acid was decreased gradually. The major organic acids from the fruit juice were citric acid, malic acid and oxalic acid. Citric acid content exceeded 90%, oxalic acid ranged less than 3.58% and malic acid ranged $0.98{\sim}9.45%$ in total organic acids. Both naringin and hesperidin content showed markedly high in immature fruits, and in rind compare to fruit juice. Naringin and hesperidin content decreased as peel coloration progressed. It was estimated that fully matured fruits would be useful for making processed products, which lead to less turbity and less bitterness.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.440-447
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• 2014

For this analysis, canopies of slender-spindle 'Hongro'/M9 apple trees were divided into 4 positions: upper, lower, exterior, and interior parts. The photosynthetic rate was highest in the external part of the upper canopy of the tree, where it was 4.5 times higher than in the internal part of the lower canopy. This difference was closely associated with differences in light penetration based on canopy position. Analysis of leaf growth characteristics showed that the leaves situated in the internal part of the canopy were larger and thinner than those in the external part of the canopy. The difference in leaf thickness was mainly due to thickness of the primary layer of palisade tissues (68.5 and $110.3{\mu}m$ for internal and external leaves, respectively). Fruit weight and quality were closely related to the extent of light penetration. Fruit weight, soluble solid content, and red skin color were higher in the fruits from the external part of the canopy. Thus, fruit maturity was delayed in the internal part of canopy. The fruit skin and wax layer were thicker in fruits from the internal canopy than in those from the external canopy. Therefore, our results indicate a need for improved light penetration in internal parts of the canopy and for split harvesting depending on maturity at different canopy positions.

• Journal of agriculture & life science
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• v.46 no.6
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• pp.9-15
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• 2012

This study was conducted to increase grape quality by treating plant growth regulator (PGR) in 'Campbell Early' grape. Foliar application of gibberellic acid ($GA_3$) at $5mg{\cdot}L^{-1}$ on flower cluster of 'Campbell Early' grape at 3-5 unfolded leaf stage effectively increased columella length, berry weight, soluble solid contents and promoted skin color development. Foliar application of $20mg{\cdot}L^{-1}$ abscisic acid (ABA) mixed with $5mg{\cdot}L^{-1}$ of $GA_3$ on flower cluster of 'Campbell Early' grape at 3-4 unfolded leaf stage effectively increased skin anthocyanin contents without any detrimental effects on berry enlargement and columella growth. Foliar application of $2.5mg{\cdot}L^{-1}$ thidiazuron mixed with $5mg{\cdot}L^{-1}$ of $GA_3$ on flower cluster of 'Campbell Early' grape at 3-4 unfolded leaf stage effectively increased fruit quality indices such as higher soluble solid contents and less titratable acidity.

• Korean Journal of Agricultural Science
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• v.40 no.2
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• pp.107-113
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• 2013

We tested fruits quality and skin coloration of two pear cultivar 'Wonhwang' and 'Whasan' produced by bagging with different kinds of paper bags in the Cheonan area, Chungnam Province, Korea. The fruits were bagged at 35, 45, 55 or 65 days after full bloom (DAFB) with 3 kinds of double layer paper bag which consisted of grey color, yellow color and newspaper for outer layer. The great extent of light interruption was observed in grey colored outer paperbag among three kinds of paperbag which showed only 0.46% of lowest light transmittance when compared with 43.7% and 40.0% of yellow paper and newspaper, respectively. The development of skin redness ($a^*$) increased with the delay of bagging time in two pear cultivars. But the fruits treated at 65 DAFB showed uneven coloration and excessive development of redness which represented low fruit external appearance value. Uniform flesh firmness was attained at the fruits bagged with grey outer color paperbag regardless of bagging time, although the fruit quality indices including soluble solids and titratable acidity did not change significantly by using different kind of fruit bags and bagging time in two pear cultivar. Based on our results, it was explained that the grey-colored fruit bag had positive effect on the development of skin coloration without any detrimental effect on fruit quality factors in 'Wonhwang' and 'Whasan' pears.

• Journal of Bio-Environment Control
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• v.17 no.4
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• pp.319-324
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• 2008

The sweet pepper (paprika) is one of the most important exported vegetable crops in Korea. This study evaluated the storability of sweet pepper fruits between 2 cultivars with different maturities under different storage conditions. The sweet peppers ('Special' and 'Fiesta') were grown in a rockwool hydroponic system, and harvested two different maturities: half-maturity and full-maturity levels. The sweet pepper fruits were stored in MA(non-ventilated) and non-MA(ventilated) conditions at 4 and $9^{\circ}C$ for 20 days. The storability of sweet pepper fruit was the highest in $4^{\circ}C$ MA conditions that remained 5% carbon dioxide and 10% oxygen during the storage. The ethylene concentration in MA condition showed $2{\sim}8{\mu}l/l$ regardless of storage temperatures, cultivars and maturities. The fruits packaged with non-ventilated film, showed lower weight loss, and higher firmness, and there was no different about decay ratio compared to the fruits packed ventilated film. The coloration of semi-matured fruit that colored 50% before storage progressed faster in non-ventilated packaging condition at $9^{\circ}C$, but their color did not changed as same as level of full-matured fruit. The electrolyte leakages and respiratory rate that estimated degree of chilling injury was highest in non-MA(ventilated) conditions of 'Special' full matured fruit placed at room temperature for 3 days following storage at $4^{\circ}C$ for 20 days. It may be suggested that sweet pepper fruit packed sealed (non-ventilated) film and stored at non-chilling temperature can be maintained better quality for long term storage.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.497-503
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• 2018

A strawberry variety 'Arihyang' was derived as an artificial cross between 'Tochiotome' and 'Seolhyang' in 2014. The seedling and line selections were conducted from 2014 to 2015. Preliminary and advanced yield trials of '14-5-5,' which was the final selected line, were conducted from 2015 to 2017. 'Arihyang' is suitable for forced cultivation and has strong plant vigor, uniformly large-sized fruit, and a high yield compared to those of the check variety, 'Seolhyang' and 'Maehyang.' Especially, vitamin C was at a significant level, which was approximately 15% higher than that of 'Seolhyang.' The average number of flowers per first flower cluster was 10.5, which could reduce the labor of thinning fruit. Its fruit has a conical shape, dark red color, and glossy skin. The fruit was of good quality but has recommendations for harvest at the fully ripened stage. 'Arihyang' has intermediate resistant to phytophthora crown rot, but is susceptible to powdery mildew, gray mold, anthracnose, and fusarium wilt. It is reguired to manage major diseases and pests using optimum cultivation techniques and chemical control.

• Journal of Bio-Environment Control
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• v.20 no.3
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• pp.211-215
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• 2011

This study aimed to determine optimum leaves per shoot in 'Campbell Early' grape through investigating changes of fruit quality after veraison 70~75 berries of first cluster and 35~40 berries of second cluster at 30 days after full bloom. Soluble solids content (SSC) increased dramatically during 28 days after veraison and afterwards it was stabilized. 15 leaves per shoot treatment showed fast increase of SSC from early veraison and reached to over 16.0oBx at 28 days after veraison. No considerable increase of SSC were occurred on either 5 or 0 leaves per shoot treatments after veraison. Titratable acidity (TA) was decreased continuously during 28 days of berry ripening in the all treatments. In 15 leaves per shoot treatment, TA decreased fast during first 7 days after veraison and continuously decreased to 0.5% by harvest time. While, 5 and 0 leaves per shoot treatments showed TA decrease slightly only at the early veraison. Hunter L and b values of 15 leaves per shoot treatment decreased fast during first 7 days of veraison, and gradually decreased by 14 days, whereas Hunter a value increased fast during the first 7 days from veraison. Total anthocyanin content in 15 leaves per shoot treatment increased fast from 7 days of veraison and the increase became slow after 28 days of veraison. Other treatments showed no significant difference from veraison to harvest time.