• Horticultural Science & Technology
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• v.31 no.5
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• pp.648-651
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• 2013

A new cultivar 'Daewang' strawberry was developed by the National Institute of Horticultural & Herbal Science for forcing culture in 2010. The cultivar 'Daewang' was originated from the cross between 'Maehyang', a high firmness cultivar and 'Wongyo 3111', a high sugar content in 2006. The cultivar shows erect plant type, vigorous growth habit, early flower bud differentiation with 12-15 flowers per cluster from planting on healthy nursery. Fruits of 'Daewang' are conical type having a bright red skin color, and 16-17 g in an average weight. 'Daewang' is suitable for forcing culture as time required for dormancy breaking ranged between 50 and 100 hours. This cultivar has excellent taste for high sugar/acid ratio as sugar content of $11.1^{\circ}Brix$, acidity of 0.39% with abundant texture and can be harvested by late spring because the fruit firmness of 'Daewang' was $18.2g{\cdot}mm^{-2}$ that was about $7.9g{\cdot}mm^{-2}$ higher than $10.3g{\cdot}mm^{-2}$ of 'Akihime' cultivar. But although total yield is not significantly different from 'Akihime' cultivar, its marketable yield is remarkably higher than that of 'Akihime' cultivar. Disease and pest resistance of 'Daewang' have a tendency to sensitive powdery mildew, anthracnose and spotted spider.

• Korean Journal of Breeding Science
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• v.42 no.4
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• pp.374-380
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• 2010

In order to select excellent cross parents in strawberry breeding, 11 varieties were self-pollinated and tested their progenies. Among the 11 varieties, 'Akihime', 'Maehyang' and 'Seolhyang' showed superior in plant vigor, disease resistance and yield. Combining ability was tested using 15 progenies obtained from crosses between 3 selected varieties as seed parents and 5 varieties as pollen parents. Plant vigor was the strongest when 'Akihime' was used as a seed parent while ripening time tended to the fastest when 'Seolhyang' as a seed parent. Average fruit weight of the crosses 'Seolhyang' ${\times}$ 'Tochiotome', 'Seolhyang' ${\times}$ 'Geumhyang', 'Seolhyang' ${\times}$ 'Wongyo 3111' and 'Akihime' ${\times}$ 'Wongyo 3111' were above 18 g for marketable fruits. Fruit hardness was superior at crosses of 'Maehyang' as a seed parents to other crosses combinations, especially 'Maehyang' ${\times}$ 'Tochiotome'. Soluble solid contents (SSC) was not significantly different among cross combinations. The best cross combination for marketable yield was 'Akihime' ${\times}$ 'Wongyo 3111', followed by 'Seolhyang' ${\times}$ 'Geumhyang', 'Maehyang' ${\times}$ 'Geumhyang', 'Akihime' ${\times}$ 'Tochiotome', in order.

• Journal of Bio-Environment Control
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• v.20 no.3
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• pp.227-232
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• 2011

The processing techniques are need to use the non-marketable paprika fruit because paprika that is difficult crop for cultivation and produced easily non-marketable fruits, such as physiological disorder fruit, malformed fruit, and small size fruit. This study was carried out to investigate the proper active modified atmosphere packaging (MAP) condition for enhancing the storability of fresh-cut paprika fruit. The fresh-cut paprika (cv 'Score', seminis) put into $7cm{\times}0.7cm$ size and packed them in 20 g bags. The active MAP and vacuum treated paprika fruits were packaged with LLDPE/Nylon, EVOH, Tie film, and injected partial pressures of $CO_2$ and $O_2$, and $N_2$ in the packages immediately after sealing to treat active MAP. The ratio of $CO_2$, $O_2$, and $N_2$ of active MAP conditions were 0 : 20 : 80 (air), 5 : 5 : 90, 30 : 10 : 60, 10 : 70 : 20 and vacuum treatment did not contain any gas. The passive packaging treated paprika packaged with $40{\mu}m$ ceramic film. After 7 days of storage at $9^{\circ}C$, the fresh weight decreased less than 2% in all treatments, and showed lower in 5 : 5 : 90 ($CO_2:O_2:N_2$) active-MAP treatment and higher in vacuum treatment than other treatments. The $CO_2$ and $O_2$ concentration in packages did not change remarkably in active-MA treatments except 30 : 10 : 60 active-MAP treatment that showed sharply decreased $O_2$, concentration and increased $CO_2$ concentration at $1^{st}$ day of storage at $9^{\circ}C$. The ethylene concentration in package was the highest in 30 : 10 : 60 active-MAP treatment and the lowest in the passive MAP treatment that packaged with gas permeable film during $9^{\circ}C$ storage for 7 days. The 30 : 10 : 60 active-MAP treatments were not proper condition to storage fresh-cut paprika. The visual quality was maintained higher in 0 : 20 : 80 (air), 5 : 5 : 90, and 10 : 70 : 20 active MAP treatments and passive MAP treatment than others and the firmness, off-odor, and electrolyte leakage was investigated at 7th day of storage at $9^{\circ}C$. The 5 : 5 : 90 and 10 : 70 : 20 active-MAP treatment showed higher firmness and lower off-odor than other treatments after $7^{th}$ day of storage at $9^{\circ}C$. In addition, the electrolyte leakage was reduced less than 20% at 0 : 20 : 80 (air), 5 : 5 : 90, 10 : 70 : 20, and passive MA treatments. Therefore, 10 : 70 : 20 ($CO_2:O_2:N_2$) and 0 : 20 : 80 (air) might be recommended for proper active MAP conditions.

• Journal of Bio-Environment Control
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• v.19 no.1
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• pp.49-54
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• 2010

The study was conducted to compare the postharvest physiology and storability of fresh cut paprika fruits classified by normal, blossom end rot(BER), and misshapen (or knots) fruit. Some disordered paprika fruits that were produced frequently during high temperature season in highland, were sorted out to non-marketable products. These fruits are mostly wasted, but some of them may be used for fresh cut. The respiration rate of fresh cut paprika fruits was lower and ethylene production rate was higher in normal fruits than in disordered fruits, but there was no significant difference. The fresh-cut paprika fruits were stored in MAP conditions at $4^{\circ}C$, $9^{\circ}C$ and room temperature in 25 ${\mu}m$ and 50 ${\mu}m$ thickness ceramic film packaging. The fresh weight of fresh cut paprika fruits decreased below to 1.1% regardless of fruit types, but the fresh weight loss increased in thinner packaging materials and lower storage temperatures. There were not significant different carbon dioxide and oxygen contents in MAP of all fruit types, while $4^{\circ}C$ storage temperature treatment and 25 ${\mu}m$ thickness ceramic film treatment had lower carbon dioxide and higher oxygen contents. Moreover, the carbon dioxide and oxygen contents were changed rapidly at 9 days in $4^{\circ}C$ storage and at 6 days in $9^{\circ}C$ storage when the visual quality of fresh cut decreased dramatically. The ethylene concentration of packages was below 7 ${\mu}l{\cdot}l^{-1}$ in all treatments during storage, while the treatments of thinner packaging material and lower storage temperature showed lower ethylene concentration. The fresh cut of disordered fruits showed less visual quality than normal fruit treatment in both $4^{\circ}C$ and $9^{\circ}C$ storage temperatures, but there was no significant difference. The value of $4^{\circ}C$ treatment that measured 12 days in storage was higher than $9^{\circ}C$ treatment that measured 9 days in storage. The results suggest that the disordered fruits may be used to fresh cut product without any concerns that they will decreased the value of commodities more quickly than the fresh cut made of marketable paprika fruits. As the fresh cut paprika fruits stored in MAP condition, the more effective storage temperature is $4^{\circ}C$ that may have induced chilling injury a whole fruit of the paprika.

• Journal of Bio-Environment Control
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• v.21 no.3
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• pp.186-191
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• 2012

Experiments were conducted to investigate the effect of fertigation (fertilizer-added irrigation) on soil EC (electrical conductivity), nitrogen and calcium content in soil, vine growth and fruit yield of oriental melon (Cucumis melo L. var. makuwa Mak.). Soil EC was increased with the frequency of fertigation (Yamazaki's solution for melon, 900 L/1,000 plants, each time) up to $0.8dS{\cdot}m^{-1}$ as compared to that of conventional irrigation ($0.2dS{\cdot}m^{-1}$). Ca content in soil also increased in fertigation fields. Vine dry weigh (20 days after planting) was significantly increased in fertigation plot. Markedly increases in marketable fruit yield and lower rate of off-shape fruit were recorded with the increase in fertigation frequency. Mean fruit weight and soluble solids contents ($^0Brix$) in fruit were not affected by fertigation. Fresh weight loss during storage was significantly higher in fruits harvested from 2 times fertigation (09:00 and 18:00) plot than conventional irrigation and the 1 time fertigation ones.

• Journal of Bio-Environment Control
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• v.7 no.2
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• pp.151-158
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• 1998

This study was carried out to evaluate the effect of substrates and nutrient solution supplying methods in the media culture using perlite and its mixtures with rice hull, carbonized rice hull. cocopeat on the growth and fruit qualify of hydroponically grown cucumber. Three substrates. Perlite(70%) +rice hull(30%) perlite(70%) +carbonized rice hull(30%) and perlite(70%)＋cocopeat(30%) were compared with perlite medium. Supplying methods of nutrient solution were composed of drip irrigation, modified drip irrigation(covered with cheesecloth between drip hose and substrate) and mist system Leaf area of cucumber Plants was lowest in perlite medium while it was highest in mixture of perlite and cocopeat. NAR was higher in the plot of mixture with cocopeat. and same trend was observed in LAI and CGR. T/R ratio was higher in Perlite and perlite mixture with rice hull. Fruit Yields increased in the plot of modified drip irrigation system. When perlite mixture with rice hull used as a substrate. mist system was recommended. Perlite mixture with carbonized rice hull was observed favored in conventional drip irrigation system. Marketable yield and the number of fruit per plant increased and the malformed fruit decreased in the plot of modified drip irrigation system with the mixtures of Perlite and cocopeat.

• Journal of Bio-Environment Control
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• v.8 no.1
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• pp.67-73
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• 1999

This experiment was conducted to investigate the effect of thermokeeping bag with 30 and 45cm width on the growth, fruit quality and yield of oriental melon. Difference of the highest temperature was not observed but the lowest temperature of thermokeeping bag with 30cm and 45cm width was higher than that of control by 0.9$^{\circ}C$ and 1.8$^{\circ}C$, respectively The highest soil temperature of thermokeeping bag with 30cm and 45cm width was higher than that of control by 1.9$^{\circ}C$ and 9.9$^{\circ}C$, respectively and the lowest soil temperature of thermokeeping bag with 30cm and 45cm width was higher than that of control by 0.9$^{\circ}C$ and 1.2$^{\circ}C$, respectively. Growth characteristics in terms of stem length, leaf number, leaf area, fresh and dry weight, fruit weight, flesh thickness and soluble solid were higher as the width of thermokeeping bag was winder. Marketable yield per 10a of 30 and 45cm thermokeeping bag was higher 5.3% and 19.2% than that of control with 996.4kg per 0.1ha.

• Journal of Bio-Environment Control
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• v.15 no.4
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• pp.335-339
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• 2006

Effects of deficit irrigation by different soil moisture-based water potential on total soluble solids and fruit yields in fresh tomato were investigated. Amount of irrigation was saved about 11%, 25% and 41% at -20 kPa,-30 kPa and -40 kPa treatment compared to the -15 kPa treatment as a standard practice, respectively. Deficit irrigation with -30 kPa and -40 kPa treatment significantly increased total soluble solids by 11% and 24% at first truss compared to the -15 kPa treatment, with no significant loss of yield, respectively. However, deficit irrigation with -30 kPa and -40 kPa treatment significantly increased total soluble solids at second and third truss, but resulted in substantial yield loss compared to the standard practice. Total fruit yields at -30 kPa and -40 kPa treatment was decreased by 16.5% and 25.1% compared to the -15 kPa treatment. However, marketable fruits based on fruit size (150$\sim$250g) was increased by 27.8% at -30 kPa treatment compared to the -15 kPa treatment.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.351-355
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• 2010

This study was conducted to determine the relationship of larval density of tobacco cutworm, Spodoptera litura (Fabricius) to damage in greenhouse sweet pepper. Laboratory experiments, cage experiments by artificial release and field investigation were carried out in 2008. The leaf consumption rate increased greatly with larval development. The damaged leaves had several round or oval shape holes on the surface or lost certain parts of them, and the fruit damaged had a conspicuous hole on the surface or scar marks around the calyx. In the field investigation, fruit damage was highly correlated with larval densities and reached 3.5% damage at maximum. Cage experiments showed that numbers of non-marketable fruit increased as increasing larval densities released. The larval density at two weeks before harvest had a high relationship with the percentage of damaged-fruit at harvest. Corresponding larval density caused 1, 3, 5% of damaged-fruit was 0.2, 0.5, 0.8 larvae per plant, respectively.

• Horticultural Science & Technology
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• v.28 no.3
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• pp.515-518
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• 2010

'Gangha' is new strawberry ($Fragaria{\times}ananassa$ Duch.) cultivar, which was released by National Institute of Highland Agriculture, RDA, in 2008. In 2004, this cultivar was originated from a cross between 'Samahberi' and 'Elan' and showed excellent ever-bearing characteristics including continuous flowering habit, high yield under long-day and high temperature condition. It was named 'Saebong No.2' after examining its characteristic and productivity in summer culture from 2006 to 2007. Again, after two regional adaptability tests in 2008, 'Gangha' was selected as an elite cultivar. The general characteristics of 'Gangha' include semi-spreading type, middle vigor, elliptic leaf, and long cluster in growth. The fruit shape is oval and fruit color is red. Fruit quality had 1ow activity, hardness but high soluble solids contents. This average fruit weight of 'Gangha' is about 12.0 g and the marketable yield is relatively high because of more flower cluster appearance. It is resistant against powdery mildew, anthracnose, and fusarium wilt. 'Gangha' is suitable for summer culture using domestic consumption because it is shows continuous flowering habit, high yield, and fruit quality under long-day and high temperature condition.