• Food Science and Preservation
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• v.10 no.3
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• pp.261-266
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• 2003

We investigated the efficacy of heat shock treatments to improve storage quality of green red pepper. Green red pepper were stored at 10$^{\circ}C$ for 4 weeks after no treatment (control) or hot water dips at 50-65$^{\circ}C$ for 10s. Treatments at 65$^{\circ}C$ generally caused high levels of heat injury on the surface of fruit. The hot water dips had no effect on firmness, Hunter ‘a’ and ‘b’ values and viable cell count by 3 weeks of storage. But color of fruit changed toward darker and redder direction and firmness was decreased by heat treatment at 4 weeks of storage. The contents of capsaicin and dihydrocapsaicin were not caused significant influence by different heat treatment, were decreased through the storage. The optimal hot water dip condition for maintaining fruit quality after prolonged storage was found to be 55$^{\circ}C$ for 10s, which can lead to reduced chilling sensitivity of green red pepper.

• Journal of Bio-Environment Control
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• v.17 no.4
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• pp.325-329
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• 2008

This study was conducted to compare the postharvest physiological characteristics of 2 paprika cultivars; 'Special', 'Fiesta' grown in 2 regions: Chuncheon(plain region) and Hwacheon(semi-high land region), and by 2 cultural methods; soil and hydroponic(rock wool culture). Respiratory rate of paprika fruit was higher in soil culture, and ethylene production was higher in Chuncheon region of both cultivars. As the thickness of fruit flesh showed thicker in Hwacheon region and hydroponic culture, the firmness of fruit was in proportion to thickness. Vitamin C content was higher in red-cultivar, 'Special'. and in Chuncheon region. Soluble solids was higher in 'Special', but there was no different between cultural regions. The fruit of both cultivars was grown smaller in Chuncheon region, and the fruit shape of 'Fiesta' progressed faster in soil culture. The surface color of fruit was higher in Hwacheon, and although there was no significantly different between cultural method, both cultivars grown by hydroponics was shown vivid color. As above results, for the long term circulation and high quality of fruit, paprika may be cultivated by hydroponics in high-altitude region.

• Horticultural Science & Technology
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• v.31 no.4
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• pp.437-446
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• 2013

This study was conducted for three years (2007, 2009, and 2010) to investigate the changes in fruit quality during maturation, and the quality and storage ability of fruits harvested at different times of 'Fuji' apple in Daegu region with a high air temperature during the fall season. Changes in apple fruit quality during the maturation period were investigated from 120-135 days to 183-198 days after full bloom. In comparing quality and storage ability of fruits harvested at different times, fruits harvested more than 180 days after full bloom were used. During the maturation period, poor coloring was the problem for 'Fuji' apple in Daegu region by the high air temperature about $20^{\circ}C$. In comparing quality of fruits harvested at different times, the soluble solid contents and hunter a value were increased by the extended harvest time. Fruit weight during harvest was not affected by different harvest time, while the fruit firmness and titratable acidity during harvest were decreased critically when the freezing damage happened. Ethylene production, fruit firmness, and titratable acidity during cold storage for twenty weeks did not differ according to the different harvest time. Soluble solid contents of fruits harvested at 216 days after full bloom in 2009 were similar at the time of harvest and cold storage. For fruits harvested at 201 days after full bloom, soluble solid content during cold storage was higher than during harvest time. However fruit firmness, soluble solid content, and titratable acidity after cold storage of fruit harvested after freezing damage was lower than those of the fruit harvested before freezing damage. The results show that the extended harvest time of 'Fuji' apples about 2-4 weeks from 180-200 days after full bloom in area with above-air temperature during fall season was seemed to be beneficial to enhancing soluble solid contents and fruit red color, but harvesting after the middle of November was dangerous because minimum air temperature began to fall under $-3.0^{\circ}C$.

• Food Science and Preservation
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• v.22 no.1
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• pp.91-99
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• 2015

This study investigated the phenolic compounds of must and wine supplemented with different concentrations (0% (no added stems), 1%, 2%, 3%, and 5%) of fruit stems during winemaking using Muscat Bailey A (MBA) grapes. The red color, and total anthocyanin, total polyphenol, and tannin contents of the must and wine significantly (p<0.05) increased with increasing added amounts of grape fruit stems, while the volatile acid content decreased with increasing added amounts of grape fruit stems. Catechin (8.16~23.08 mg/L), gallic acid (2.32~3.28 mg/L), trans-resveratrol (1.38~3.27 mg/L), and ferulic acid (1.51~1.59 mg/L) were detected in the must and wine via HPLC. The bioactive substance contents increased with increasing added amounts of grape fruit stems, except for ferulic acid. The DPPH $IC_{50}$ activity was higher in the wine (12 mg/L) with 5% grape fruit stems than in ascorbic acid (67 mg/L). These results suggest that the fruit stems of MBA grapes can be used as functional materials for winemaking.

• Korean Journal of Environmental Agriculture
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• v.41 no.4
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• pp.328-334
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• 2022

BACKGROUND: The low temperature at flowering period break the balance between vegetative and reproductive growth of apple tree. Summer pruning has been used to control vegetative growth. So, this study was conducted to investigate the effect of summer pruning time on shoot growth and fruit quality of 'Fuji'/M.9 apple trees damaged by the low temperature at flowering period. METHODS AND RESULTS: The following treatments were applied to tree : a) control (no summer pruning), b) pruned 26 June, c) pruned 30 July, d) pruned 28 August, and e) pruned 26 September. The summer pruning significantly increased light penetration and fruit red color by reducing the total shoot growth compared with control. And the summer pruning control the outbreak of apple valsa canker. But the summer pruning at the end of June increased regrowth of shoot and pruning weight compared with the summer pruning at the end of August. The summer pruning at 30 July had the highest fruit weight, but return bloom was the highest in the summer pruning at 28 August. CONCLUSION(S): These results indicated the optimum summer pruning time of 'Fuji'/M.9 apple trees damaged by the low temperature at flowering period were the end of August.

• Journal of Bio-Environment Control
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• v.28 no.1
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• pp.55-65
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• 2019

The effects of stigma removal from floral organ and treatment of auxin on those regions were evaluated on the fruit growth and quality in strawberry (Fragaria ananassa Duch.). The removal of stigma reduced the fruit weight, fruit length, and fruit width, while fruit growth declined as the number of removed stigma increased. The removal of stigma also resulted in reduced fruit firmness, sugar content, and total anthocyanin content, and decreased value of Hunter a for red color and increased value of Hunter b for yellow. The number of seeds deceased as the regions of removed stigma increased. The treatment of auxin on the region of removed stigma improved fruit size, while it reduced fruit firmness, sugar content, and anthocyanin content. The delay in fruit ripening was observed from both stigma removal and auxin treatment. The incidence of malformed fruits increased as the regions with removed stigma increased. The treatment of auxin also promoted fruit malformation.

• Korean Journal of Agricultural Science
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• v.49 no.3
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• pp.421-430
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• 2022

Crop load management in apple trees is important for achieving optimum productivity and crop value. Hence, we investigated the influence of different crop loads on the fruit quality, mineral content, and yield of the 'RubyS' apple variety. After 4 weeks of full bloom, the crop load was adjusted by hand thinning to different (5, 10, and 15 fruits·cm^-2) trunk cross-sectional areas (TCSA), representing low, medium, and high crop loads. The low crop load increased the fruit size and weight, the development of the red-blushed area, and the peel color a^* at harvest; however, it reduced the total number of fruits·tree^-1 and yield compared with that of the other crop loads. The medium crop load improved the fruit weight, flesh firmness, and soluble solids content and reduced the fruits·tree^-1 but did not affect the fruit size and yield. However, there were no significant differences in the titratable acidity and starch index among the crop loads. The fruit mineral content (phosphorus and potassium) was higher in the low and medium crop loads compared to the high crop load. However, the nitrogen, calcium, and magnesium contents in the fruits were not affected by the crop loads. Overall, this study suggests that a low crop load improves the fruit size and weight, but its effect on the quality and fruit mineral content is similar to that of a medium crop load. Therefore, the optimum crop load level for the 'RubyS' apple trees was approximately 10 fruits·cm^-2 TCSA.

• Journal of Bio-Environment Control
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• v.31 no.4
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• pp.384-392
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• 2022

The objective of this study was to estimated nitrogen content and chlorophyll using RGB, Hyperspectral sensors to diagnose of nitrogen nutrition in apple tree leaves. Spectral data were acquired through image processing after shooting with high resolution RGB and hyperspectral sensor for two-year-old 'Hongro/M.9' apple. Growth data measured chlorophyll and leaf nitrogen content (LNC) immediately after shooting. The growth model was developed by using regression analysis (simple, multi, partial least squared) with growth data (chlorophyll, LNC) and spectral data (SPAD meter, color vegetation index, wavelength). As a result, chlorophyll and LNC showed a statistically significant difference according to nitrogen fertilizer level regardless of date. Leaf color became pale as the nutrients in the leaf were transferred to the fruit as over time. RGB sensor showed a statistically significant difference at the red wavelength regardless of the date. Also hyperspectral sensor showed a spectral difference depend on nitrogen fertilizer level for non-visible wavelength than visible wavelength at June 10th and July 14th. The estimation model performance of chlorophyll, LNC showed Partial least squared regression using hyperspectral data better than Simple and multiple linear regression using RGB data (Chlorophyll R²: 81%, LNC: 81%). The reason is that hyperspectral sensor has a narrow Full Half at Width Maximum (FWHM) and broad wavelength range (400-1,000 nm), so it is thought that the spectral analysis of crop was possible due to stress cause by nitrogen deficiency. In future study, it is thought that it will contribute to development of high quality and stable fruit production technology by diagnosis model of physiology and pest for all growth stage of tree using hyperspectral imagery.

• Horticultural Science & Technology
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• v.29 no.6
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• pp.531-538
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• 2011

This study was carried out to investigate the influence of defoliation by Marssonina blotch (Diplocarpon mali Harada et Sawamura) on vegetative growth and fruit quality in 'Fuji'/M.9 apple tree. Soluble solid contents decreased when the defoliation percentage by Marssonina blotch was over 10% before the end of September, and fruit weight decreased when percentage of defoliation was over 30%. Fruit red color and starch contents tend to decrease as percentage of defoliation near the fruit increased. Return bloom, fruit weight, and shoot growth the following year tend to decrease as percentage of defoliation increased. Photosynthetic rate of healthy leaves in bourse shoot during the end of September was maintained about $10{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, effects in increasing fruit growth and soluble solid contents after the end of September. Photosynthetic rates for the damaged leaf, damaged area was over 50% on the leaf surface, while 30% of the photosynthetic rates of healthy leaf are without damage applied with Marssonina blotch at the end of September. The results show that the decrease of fruit quality in defoliation treatments may be caused by the decrease of starch contents in fruit, and that was caused by the photosynthetic rates of leaves near fruit was decreased by Marssonina blotch in the wake of August.

• Korean Journal of Plant Resources
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• v.35 no.6
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• pp.825-830
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• 2022

"Doha" is a new strawberry (Fragaria x ananassa Duch.) variety, which was released by the Highland Agriculture Research Institute in 2021. The "Doha" variety originates from a 2014 cross between "Saebong No. 3" and "Yeolha," both of which exhibited excellent ever-bearing characteristics, including continuous flowering and large fruits under long-day and high temperature conditions. This new cultivar was initially named "Saebong No. 13" after examining its characteristics and productivity during summer cultivation between 2015 and 2018. After regional adaptability tests, "Doha" was selected from "Saebong No. 13" as an elite cultivar. The general characteristics of "Doha" include spreading, elliptic leaves, and strong growth. The fruits are long and conical and of a red color. The plant height of "Doha" was similar to that of "Goha," but the number of leaves was lower. The number of flower clusters of "Doha" was 8.6, which was 2.8 fewer than that of the control variety, "Goha," with 11.4. The average fruit weight of "Doha" was 13.9 g, which was 4.9 g heavier than that of "Goha." The fruit hardness of "Doha" was 35.5 g·mm^-2, which was 9.4 g·mm^-2 harder than that of "Goha." The marketable yield of "Doha" was 26,971 kg·ha^-1, 125% more than that of "Goha" with 21,479 kg·ha^-1. The findings of this study suggest that "Doha" is a hard fruit and high-yielding variety of ever-bearing strawberries that could increase farming income when distributing to farmers.