• Korean Journal of Soil Science and Fertilizer
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• v.12 no.2
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• pp.99-107
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• 1979

The properties, land use and genesis of the Jang-weon series, Planosol-like soils, distributed in Cheong-do area were investigated. Planosol-like soils in Korea have been believed unsuitable for perennial crops but 34.6% (594ha) of the Jang-weon soils in Cheongdo-gun are used for perennial crops such as apples, persimmons, peaches, mulberry etc. With productivity more or less equal to alluvial soils. The reason for high productivity and a working hypothesis for the genesis of the fragipan is suggested with discussion.

• The Korean Journal of Pesticide Science
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• v.17 no.1
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• pp.6-12
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• 2013

Methoxyfenozide and novaluron were sprayed with single and triple treatments separately on peach during cultivation period. Samples were collected over 14 days, 8 times in total (0, 2, 4, 6, 8, 10, 12, 14 days). Methoxyfenozide and novaluron were extracted with acetone and partitioned with dichloromethane, and analyzed by HPLC/DAD. Method Quantitation Limit (MQL) were both 0.005 mg/kg, average recoveries of methoxyfenozide at two fortification levels of 0.05 and 0.25 mg/kg were determined $92.7{\pm}2.9%$ and $102.8{\pm}3.1%$, and novaluron were $98.2{\pm}4.8%$ and $96.7{\pm}9.0%$, respectively. The biological half-life of methoxyfenozide was about 4.41 days at single treatment, and 4.24 days at triple treatments. The biological half-life of novaluron was about 14.81 days at single treatment, and 14.50 days at triple treatments. Dissipation of pesticides on peach was influenced by growth dilution effect. In case of application of methoxyfenozide and novaluron following guidelines on safe use of pesticides, the final residue level was predicted to be lower than Maximum Residue Limit (MRL).

• Horticultural Science & Technology
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• v.30 no.1
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• pp.42-49
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• 2012

This experiment was conducted to find out the effects of nitrous oxide ($N_2O$) on the postharvest quality of 'Janghowon hwangdo' peach fruits. Fruits were harvested at commercial maturity for marketing in late September, and treated with 70% $N_2O$ + 20% $O_2$ + 10% air, 80% $N_2O$ + 20% $O_2$, and 90% $N_2O$ + 10% $O_2$ for 48 h, and then stored at $15^{\circ}C$. No significant treatments for soluble sugar and titratable acidity contents were detected. However, good appearance and taste in peach fruit were maintained better in 80% $N_2O$ treatment than in air treatment. The treatment with 90% $N_2O$ had negative effects on weight loss and taste because of rotting by anaerobic fermentation. 80% $N_2O$ treated fruit had significantly higher fungus (Botrytis cinerea) growth inhibition of saprogenic approximately than air treatment until 12 days of storage. The browning and rotting at surface of peach were also retarded when peaches were treated with 80% $N_2O$ before they were artificially wounded. The activity of polyphenol oxidase (PPO) was inhibited about 80% in peach of 80% $N_2O$ treatment compared with in air treatment. The result showed that 80% $N_2O$ treatment was able to extend the shelf life of peach fruits through maintaining taste and inhibition of softening and browning by rotting and wounding during storage.

• Horticultural Science & Technology
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• v.30 no.1
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• pp.1-5
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• 2012

This study was conducted to elucidate the cause of micro-cracking in the exocarp of 'Jinmi' peach (Prunus persica). through the microscopic observation of fruit skin development in 4 varieties such as 'Jinmi', 'Kanoiwa Hakuto', 'Kawanakajima Hakuto', and 'Yumyeong'. Micro-cracking was noted in 59.1% of 'Jinmi', 30.6% of 'Kanoiwa Hakuto', 21.5% 'Kawanakajima Hakuto' and 6.4% of 'Yumyeong', respectively. The development of intercellular spaces, which increased rapidly with the fruit development, was easily observed at 69 days after full bloom. Histological studies revealed that the number of outer epiderm cell layers of 'Jinmi' was smaller than that of the other three cultivars, and thinner than the 'Kawanakajima Hakuto' and 'Yumyeong'. Moreover, 'Jinmi' exhibited smaller and flatter shapes in the sub-epidermal cell layer than those of the 'Kawanakajima Hakuto' and 'Yumyeong' at harvest season. Therefore, these results suggest that micro-cracking of 'Jinmi' fruit skin was due to poor-developed outer epidermis and well-developed intercellular spaces just under exocarp as compared with other varieties.

• The Korean Journal of Pesticide Science
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• v.12 no.3
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• pp.291-294
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• 2008

The Streptomyces padanus isolate TH04, isolated from mummified peaches, showed strong antifungal activity to Monilinia fructicola. The inhibition activity of the isolate TH04 to mycelial growth and spore germination at 1% concentration of sub-antifungal powder made from culture suspension (CS) was ranged from 79.8% to 81.0% and from 73.9% to 75.8% to M. fructicola four strains, respectively. In the test of antifungal activity in mixed culture of the isolate and M. fructicola, inhibition rate was 7.5%, 86.8% and 94.0% in 0.01, 0.1, and 1% concentration of CS containing bacterial cell of the isolate, respectively. On apples (cultivar; Fuji), the control values of the isolate TH04 crude filtrates (0.1 and 1%) were 85.9% and 100%, respectively. The results suggest that the isolate TH04 indicate development possibility as biocontrol agent of brown rot caused by M. fructicola with the study on delivery method and fermentation condition to produce an antifungal compound.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.11
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• pp.6646-6651
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• 2014

This study was carried out to find the social welfare effects of agricultural outlook information service for fruit in Korea. The goals of an agricultural outlook information service are to improve the efficiency of the agricultural product market, and stabilize the farmer's income and consumer price. This paper introduces the results of econometric analysis for the effects of social welfare benefits. According to the results of econometric analysis for the citrus industry, the effects of the social welfare benefits were estimated to be 15,228 million KRW on apples (ratio of the total revenue, 1.5%), 3,154 million KRW on pears (ratio of the total revenue, 1.8%), 1,936 million KRW on peaches (ratio of the total revenue, 0.9%), 5,211 million KRW on grapes (ratio of the total revenue, 1.0%), 44,976 million KRW on citrus (ratio of the total revenue, 5.4%), and 2,590 million KRW on sweet persimmon (ratio of the total revenue, 0.8%) in 2012.

• The Korean Journal of Food And Nutrition
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• v.27 no.2
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• pp.219-224
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• 2014

To increase the shelf-life of domestic peach, peaches were treated with hot air ($46^{\circ}C$) for 0~9 hours and the changes in the major components contents and antioxidative activities were investigated. Ascorbic acid content of the control and hot air treatments were 13.81 mg% and 11.73~14.16 mg% respectively, however, there was no significant difference between them. The contents of polyphenols of the control and hot air treatments were 22.64 mg% and 19.03~23.19 mg% respectively, but there was no significant difference between them. The contents of polyphenols of the control were slightly lower than those of hot air treatments during storage. Also the contents of flavonoid were not significantly different among the control and hot air treatments. The detected free sugars of the control and hot air treatments were fructose, glucose, maltose and sucrose. Among the free sugars detected, sucrose content was the highest and free sugar content did not change during storage periods. Furthermore, antioxidative activities were not different among the control and hot air treatments.

• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.573-577
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• 2013

To extend the shelf-life of the domestic peach, a low dose UV-C irradiation (0~3.0 $kJ/m^2$) was treated and the changes of the major chemical components were investigated. The contents of polyphenols in UV-treated peaches were higher than that of control with the highest at 0.25 $kJ/m^2$ UV treatment. The contents of polyphenols of control and UV treatments were slightly reduced by storage period. The contents of flavonoid were not significantly different among the control and UV treatments. Detected free sugars of the control and UV treatments were fructose, glucose, maltose and sucrose. Sucrose content was higher than that of other free sugars and free sugar content increased during storage. And free sugar content was not significantly different between the control and UV treatments. The free amino acid content of the control and UV treatments were 115.38 mg% and 95.92~120.94 mg% respectively, but there was no significant difference between the control and UV treatments.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.531-537
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• 2000

The simple microgel electrophoresis of single cells, a 'comet assay', on fruit seeds enabled the rapid identification of irradiated fruits by comparing the intact non-irradiated cells and the damaged cells of irradiated fruits. Grapes and plums were irradiated with 0.1, 0.5, 0.7, 1.0 kGy and strawberries, peaches, apples, and nectarines were irradiated with only 1.0 kGy. Seeds were isolated, crushed, and the suspended cells were embedded in an agarose layer. After lysis of the cells, they were subjected to microgel electrophoresis for 2 minutes, and then stained. The DNA radiation-induced fragmentation of all the fruits stretched and migrated out of the cells forming a tail toward the anode giving the appearance of a comet, while the undamaged cells appeared as intact nuclei without tails. Grape and plum seeds irradiated at 0.5 kGy and higher showed significant increases in tail length. With increasing the irradiation doses, longer extention of the DNA from the nucleus toward the anode was observed. Strawberry, peach, apple, and nectarine seeds irradiated with 1.0 kGy also showed the longer tails than non-irradiated ones. DNA comet assay as a rapid and inexpensive screening technique could be an officially validated method for the detection of irradiated fruits.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.3
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• pp.364-371
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• 2009

The effect of gamma irradiation ($0.5{\sim}2$ kGy) on the microbiological, physicochemical and sensory properties of peaches was investigated during 6 day storage at $20{\pm}3^{\circ}C$. Total aerobic bacteria, yeasts and molds significantly decreased with increasing dose level. In Hunter's color values, L-values decreased and a- and b-values increased with increment of irradiation dose level. Hardness significantly decreased with increment of irradiation dose level whereas pH, soluble solid, and total polyphenol contents increased with increment of irradiation dose level. DPPH (1,1-diphenyl-2-picrylhydrazyl) radical-scavenging activity of irradiated peach was higher than that of control and its activity increased with increment of irradiation dose level. Vitamin C content was not affected by irradiation. In sensory test, overall acceptabilities of irradiated samples were higher than those of control. These results suggest that gamma irradiation on peach was effective for microbiological safety while improving the antioxidant activity, but not good on color and texture of peach.