• Horticultural Science & Technology
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• v.31 no.6
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• pp.687-699
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• 2013

This study was conducted to examine the effect of grafted peppers (Capsicum annuum) on different rootstocks on fruit quality. Three pepper cultivars, 'Nokkwang', 'Saengsaeng Matkkwari', and 'Shinhong' were grafted onto five commercial rootstocks that are known to be resistant to Phytophtora blight. Non-grafted or auto-grafted peppers were used as controls. Grafted plants were grown during two consecutive harvest periods by semi-forcing culture (April to August) and retarding culture (September to March the subsequent year). Full size green fruits were harvested and weighed weekly from June to August (Semi-forcing culture) and from December to March of the subsequent year (Retarding culture). The fruit size, weight, flesh thickness, and firmness were measured every month. Total marketable yield was not significantly influenced by either auto-graft of 'Nokkwang', 'Saengsaeng Matkkwari', and 'Shinhong' of pepper or grafted with the five commercial rootsctocks. By contrast, grafting influenced the apparent fruit quality of peppers. Fruit characteristics differed depending on the rootstock cultivars. However, the fruit characteristics of rootstock did not affect the fruit characteristics of scion grafted onto that rootstock. Fruit characteristics in each treatment differed among harvest time (first, second, and third harvest). Fruit quality parameters were also different as affected by the harvest period. In conclusion, apparent quality and textural property of pepper fruits were influenced by not only grafting with different rootstocks but also by the harvest period and harvest time. Accordingly, rootstock/scion combination, the scion variety and the harvest period must be carefully chosen to get the desired optimal fruit quality.

• The Journal of Natural Sciences
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• v.4
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• pp.161-177
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• 1991

This experiment was carrid out to investigate the effect of organic fertilizer and plant growth regulators application on the growth and quality of tomato. The results are summarized as follows. 1. Plant height of tomato was recorded highest when chemical fertilizer plus organic fertilizer was applied, and did not have significant effects in number of leaf. But stem diameter was positively effected by chemical plus organic fertilizer application than chemical fertilizer alone. 2. Flower formation, flower weight, anther weight and ovary weight were generally increased by organic fertilizer application. 3. Fruit-set and number of flower were significantly increased by organic fertilizer application. 4. Deformity fruit was the lowest rate at chemical plus organic fertilizer application when it was 14.7 percent, and it was increased by chemical fertilizer application. 5. Days of ripening was slightly delayed by organic fertilizer application and also flowering date shortened by chemical fertilizer application. 6. Plant growth regulators had positive effects on number of flower, flower weight, anther weight, and ovary weight, and variations of their effect by cluster were apparent. 7. Fruit-set was increased by 2,4-D 10ppm and BA 20ppm treatments but was decreased by treatments of Ethephon 10ppm and control. 8. By the BA 20ppm and 2,4-D 10ppm treatments, the rate of deformity fruit was decreased and fruit ripening date was also shortened.

• Horticultural Science & Technology
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• v.30 no.2
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• pp.158-161
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• 2012

The influence of lysophosphatidylethanolamine (LPE) on anti-senescence of melon leaves and the change in fruit quality during the storage at low temperature were studied. In most of the crops, freshness of leaves is important factor for characteristics of fruits, such as sugar contents, color, and firmness. Melon ($Cucumis$ $melo$ L. cv. Prince) plants were sprayed with LPE at 5 and 3 weeks before commercial harvest. In upper part, LPE treatment showed slight high number of fresh leaf compared to no treatment (None). However, in lower part, LPE resulted in apparent inhibition effect on senescence, showing that lower side of melon plant kept fresh upon LPE application up to about 30%. The SSC of melon treated with LPE was similar to that of fruit from None at harvest. There was no change in soluble solids content (SSC) for all treatment during the storage at $7^{\circ}C$. There were no significant differences in firmness of mesocarp from melons given different treatments at harvest. The firmness of mesocarp from melon treated with LPE was higher than none after 2 weeks storage. The electrolyte leakage means for melon treated with LPE did not differ significantly from the means at initial storage after 2 weeks storage among the treatments. None increased 57% from its initial electrolyte leakage during storage. These results suggest that the application of LPE may have potential to inhibit senescence of leaves and maintain fruit quality during the storage in melon.

• Food Science and Preservation
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• v.16 no.4
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• pp.459-462
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• 2009

'Fuyu' (Diospyros kaki L.) is an important sweet persimmon cultivar, and the fruits are often stored in a modified atmosphere after harvesting in South Korea. However, blossom-end browning and darkening of fruit often occur after harvest or during storage, which decreases fruit quality in the fresh fruit market. High fruit calcium concentration would reduce oxidation of phenolic compounds in the cytoplasm such oxidation is responsible for fruit browning. This study investigated the effects of soluble calcium fertilization and foliar application, and indole-3-butyric acid (IBA) fertilization on fruit quality and browning. Trees received one of the following five treatments: 1) control (no calcium or IBA); 2) calcium fertilization (Ca FG, 2 mL per tree); 3) calcium foliar application (Ca FA, 2 mL); 4) calcium and IBA fertilization (Ca+IBA) 5) IBA fertilization (IBA, 2 mL. Fruit calcium concentration was highest in trees treated by Ca FA, and lowest in control trees. Generally, fruit calcium concentration was high in the stem end but low in the blossom end, which usually first develops fruit-browning symptoms. There were no apparent differences in fruit qualities such as firmness, soluble solid content, and weight among treatments. Fruit browning occurred at frequencies of about 14%, 20%, and 50% on Ca FA, Ca FG, and control trees, respectively. Therefore, the improved fruit calcium level seen when trees received Ca or IBA application tended to prevent fruit browning, which increased fruit quality and storage properties.

• Journal of the Korean Society for Nondestructive Testing
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• v.28 no.3
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• pp.279-284
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• 2008

The firmness of fruit is one of the most important quality factors and is highly correlated to the elastic modulus. In this study, the ultrasonic transmission method was applied to evaluate the elastic modulus of the apple. In order to transmit and receive the ultrasonic wave through the whole apple, the ultrasonic measurement setup consisted of ultrasonic pulser, two specially fabricated ultrasonic transducers for fruit and digital storage oscilloscope. Ultrasonic parameters such as ultrasonic wave velocity, apparent attenuation, and peak frequencies were analyzed. The elastic modulus of apple was measured by using compression test apparatus. The correlations between ultrasonic parameters and elastic modulus were analyzed. A multiple linear regression model describing the relationship between elastic modulus and ultrasonic parameters was proposed.

• Journal of Biosystems Engineering
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• v.24 no.3
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• pp.243-252
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• 1999

The damage caused in the processes and distributions after harvesting the fruits and vegetables is attributed to the mechanical factors such as compressive and impact forces. Compression tests of biological materials provide an objective method for determining the apparent modulus of elasticity and mechanical properties which are significant in quality evaluation and control, and them maximum allowable compressive forces for minimizing mechanical damage. This study was performed to determine the mechanical properties of apple and pear, and to investigate effect of specimen shapes on the mechanical properties of them. A computer program was developed for measuring the mechanical properties and analyzing the data obtained from the measurement. Compression tests on the sample were performed with then replications at each treatment and at 25 mm/min loading rate. Mechanical properties of the apple was generally shown the higher value than those of the pear, and it was though that data obtained form the cylindrical specimen removed from the sample was more reliable than from the specimen cut in half.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.6
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• pp.1882-1888
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• 2008

Effects of 1-MCP(1-methylcyclopropene) on the postharvest life and fruit quality of cucumber 'Baekdadaki' were investigated. Cucumber were held at room and cold chamber($10^{\circ}C$) treated with several concentrations of 1-MCP. Physico-chemical characteristics such as fresh weight and firmness were greatly varied during storage, and the treatment with I-MCP(500ppb) showed the minimal loss of the values at harvest. The peel b value representing a senescence process was higher investigated in 1-MCP(250 and 1,000ppb treatment, and led to the apparent yellowing and softening after cold storage for 15 days. 1-MCP(500ppb) showed lower decay rate and better marketability of cucumber than other treatments after cold storage for 15 days. The respiration rate was higher found in cucumber treated with 1-MCP(250ppb) than in other treatment. Ethylene evolution was most detected in cucumber treated with 1-MCP(1000ppb) after room storage for 6 days. 1-MCP did not affect the production of ethylene in cucumber during room and cold storage.

• Food Science and Preservation
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• v.17 no.1
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• pp.72-78
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• 2010

To develop a low-ethanol strawberry wine, the use of pectinase to improve the extraction yield of strawberry juice was investigated, and changes in physicochemical characteristics during ethanolic fermentation were assessed. The juice yield from strawberry fruit increased by 18.9% after Viscozyme L treatment (1,000 ppm, 30 min), compared with a control group, a greater increase than seen with other pectinases (17.5-18.7%). No significant quality differences were observed between control juice and juice prepared with enzyme treatment, indicating that neither physicochemical characteristics nor ethanol content during fermentation were affected by pectinase treatment. The major pigments of strawberry juice were cyanidin-3-glucoside and pelargonidin-3-glucoside, both of which are anthocyanins. The pigment level after enzyme treatment was slightly lower than that of the control group, at all fermentation times. We consider that the economics of strawberry wine manufacture may be increased by use of pectinase because juice level was increased, but no change in ethanol content or physicochemical characteristics was apparent.

• Korean Journal of Environmental Agriculture
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• v.32 no.2
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• pp.166-170
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• 2013

BACKGROUND: Persimmon growers have often tried various regimens of K fertilization to improve fruit quality. This experiment was conducted to determine the effects of K rates on concentration of inorganic elements in different tree organs and on fruit characteristics. METHODS AND RESULTS: Six-year-old non-astringent 'Fuyu' persimmons, grown in 50-L pots, were used. Total K amounts of 0 (no-application), 12, 25, 37, and 66 g were fertigated to a pot with KCl solution at 3-to 4-day intervals from July to September. The 0 K trees received no K fertilizer for the two previous years. Leaves, fruits, and shoots were sampled in November. K concentrations in leaves and shoots increased significantly by increasing K rate; leaf K, 0.49% for the 0 K, increased to 3.09% for the 37 g and 3.11% for the 66 g trees. Fruit K was notably lower for the 0 K, but there were no significant differences among the trees as long as they were supplied with more than 12-g K. In the trees with 0 K, leaf necrosis in the margin was apparent in June and the symptom progressed toward the midrib. Some leaves scorch-rolled from the margin in August. The greatest effect of K rates was on fruit size; it significantly increased to 181 g for the 12 g, 203 g for the 37 g, and 206 g for the 66 g compared with 150 g for the 0 K trees. However, K rates did not affect firmness and soluble solids of the fruits. The fruits of the 0 K trees were characterized by better coloration. CONCLUSION(S): The K-rate effect on inorganic elements depended on tree organs and fruit size was the major parameter to be affected by the K rates.

• Journal of Bio-Environment Control
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• v.30 no.3
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• pp.230-236
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• 2021

Changes in greenhouse temperature and solar radiation due to fogging and shading were monitored during hydroponics in high temperature in summer season. Experiment 1 consists of four treatments, namely, Control, Shading, Fogging, and Fogging + Shading based on sunny days August. For Experiment 2, two melon cultivars of 'Dalgona' and 'Sopoong gaza' were cultivated in summer of 2020 using Fogging + Shading with the best result for temperature reduction effect from Experiment 1. As a result of Experiment 1, the effect of Fogging + Shading on temperature reduction was apparent where the inside was about 4℃ (as the lowest temperature) lower than the outside. Fogging + Shading showed the inside was 2-4℃ lower than the outside, and Fogging or Shading treatments had little difference, compared to the Control where the internal temperature of greenhouse was 3-4℃ higher than the external. For solar radiation changes between greenhouse inside and outside, the internal change was in a similar pattern between Fogging and Control, and between Shading and Fogging + Shading, respectively. In case of the Fogging treatment (similar with the Control) only the effect of solar radiation reduction as influenced by plastic greenhouse covering materials was examined. The Fogging + Shading had a very similar change in solar radiation to the Shading. Based on these results, Experiment 2 was conducted in summer of 2020 and resulted in a temperature reduction effect of about 3.9℃ according as the inside of air-conditioned greenhouse was kept 32.4℃ when the maximum temperature of the outside reached 36.3℃ in August during the cultivation period. In addition, the quality of melon fruit was good (1.3-1.5 kg of fruit weight, 12.6-13.3 of soluble solids content. In the case of using Fogging + Shading cooling treatment, it can bring about the effect of reducing the temperature during the high temperature in summer, and normal growth of melon and fruit harvesting were possible.