• Food Science and Preservation
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• v.20 no.1
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• pp.14-22
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• 2013

The effects of the initial storage temperature and the PA film packaging on the extension of the shelf-life and the improvement of the postharvest storage quality of muskmelons were studied during their storage. Their storage quality was tested as follows: PA-film-wrapped muskmelons, stored at $2^{\circ}C$ or $7^{\circ}C$ for 30 days after their harvest, were kept at $10^{\circ}C$ for 27 days (total: 57 days). On the fifth day of storage at $10^{\circ}C$ (35th day overall), the weight loss reached 6.4% in the 7-control. However, the 2-PA showed the smallest loss of 2.2%. The soluble solids content and the acidity that were measured before the storage were $10.8^{\circ}Brix$ and 0.26% in all the groups. After 27 days of storage at $10^{\circ}C$ (on the 57th day overall), the values were highest in the 2-PA group with $9.7^{\circ}Brix$ and 0.15%, respectively. Microorganisms were not detected at first; but on the fifth day of storage at $10^{\circ}C$ (35th day overall), their values were 3.87 and 2.68 log CFU/g in the seven-control and the 2-PA, respectively. In other words, the 2-PA was found to be more effective in inhibiting microbial proliferation. In relation to sensory properties such as appearance, flavor, sweetness and chewiness, the 2-PA was superior to the other groups and was found to be most effective in improving the storability of muskmelons. In conclusion, it was found that low-temperature injury and fast storage quality deterioration did not occur in film-wrapped muskmelons that were stored at $2^{\circ}C$ for 30 days after they were harvested.

• Korean Journal of Medicinal Crop Science
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• v.15 no.6
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• pp.367-370
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• 2007

To make the soil moisture proper is the important factor in the seedbed cultivation of Yangjik for producing a good quality of ginseng seedling. This study was carries out to investigate the effect of soil moisture on photosynthesis and yield of ginseng seedling under the different condition of the soil moisture, such as $100{\sim}400$ mbar. Photosynthesis rate was decreased gradually by the reduction of soil moisture, and in particular it was decreased distinctly under the lower condition of soil moisture, such as $300{\sim}400$ mbar. Photosynthesis rate in air temperature of $30^{\circ}C$ was decreased more distinct than that of $25^{\circ}C$, Light saturation point of leaves was at the quantum of $600{\mu}mol/m^3/s$ at $25^{\circ}C$ while it was decreased by $300{\mu}mol/m^3/s$ at $30^{\circ}C$ according to the increase of air temperature. Respiration rate was increased by the increase of quantum, and decreased by the reduction of soil moisture. Respiration rate under the condition of high quantum was increased regardless of air temperature, but it was decreased distinctly under the condition of low soil moisture and high air temperature, such as 400 mbar at $30^{\circ}C$. There were a gradual decrease by the reduction of soil moisture in leaf length, leaf width, chlorophyll content, and water content of leaves, but heat injury ratio was increased distinctly by the reduction of it. Total root weight, root weight per plant, the yield of usable seedling were decreased by the reduction of soil moisture, and optimal content of soil moisture to produce a good quality of seedling was 63% of field capacity or 18.9% in absolute soil moisture content.

• Korean Journal of Weed Science
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• v.3 no.1
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• pp.105-110
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• 1983

In order to select the effective herbicides on polyethylene film mulching culture of galic (Allium sativum L) for weed control in early and low temperature condition, several experiments were conducted at the Chungbuk Provincial Office of Rural Development from 1978 to 1982. The dominated weed in the open field was Chenopodium album (98.1%), and there were many Rvrippa globosas (39.7%), and Dtgitaria sanguinalis (34.3%) in the polyethylene film mulching culture. Effective herbicides in polyethylene film culture were alachlor EC, pendimethalin EC, oxyfluorfen EC, and acifluorfen EC. After the 15th May, metabenzthiazuron WP and prometryne WP for the gramineous weeds were effective. There was a little chemical injury on acifluorfen EC application, but not another influence on the yield. With the effective herbicides application in the polyethylene film mulching culture, yield (22-23%) and profits (26.84) to the nonmuiching culture were increased. Increase of yield (20%) and profits (56%) in black opaque polyethylene film mulching culture compared with the conventional culture was possible.

• Asian Journal of Turfgrass Science
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• v.19 no.2
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• pp.131-140
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• 2005

This study was conducted to compare cold tolerances and growth rates of 5 basic species, commercial lines, and breeding lines of zoysiagrass. Total 41 zoysiagrasses were tested at the northern part (Jeokseong-myeon) and the middle part (Cheonan) of South Korea. Cold tolerance (survival rate during winter), growth rate, green-up speed, and density data were collected visually. Four types of zoysiagrasses (Z. matrella, Z. tenuifolia, USm, and S4M2) with genetic characteristics of Z. matrella died during winter cold, while the others survived. Midium leaf type zoysiagrasses, such as Anyang1, Samdeock1, Anyang2, SJ21, and Pyeongdong, with genetic characteristics of both Z. sinica and Z. macrostachya showed vigorous growth rate one year after planting at the northern part (Jeokseong-myeon). Twenty nine ($70.7\%$) zoysiagrasses showed vigorous growth rate, but the other twelve ($29.3\%$) zoysiagrasses died by cold and drought condition at the middle (Cheonan) part of S. Korea. Anyang2, AJ9-7, Samdeock1, Samdeock2, Samdeock3, and Zenith-C showed vigorous growth rate even though cold and drought environmental condition were artificially provided at these region. But, SJ2-19, NSm, 88Mey, 88Mey-7S, 88Mey-9S, SJ2l-10, ASm, and DBm which did not die at the northern part, showed serious injury at the middle part of S. korea. From this results, we can conclude that drought is as important factor as low temperature for zoysiagrasses during winter.

• Journal of Chest Surgery
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• v.37 no.2
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• pp.113-118
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• 2004

The studies on cryopreserved arterial allograft have been focused on cooling methods, pre-treatment, cryoprotectant agents, and preservation temperature. But recently, several studies have reported that thawing methods also play an important role in the occurrence of macroscopic and microscopic cracks. This study was designed to investigate the cell injury after thawing, using a rabbit model to clarify the effect of thawing methods on cryopreserved arteries. Material and Method: Segments of the rabbit aorta were obtained and divided into 3 groups (n=60) according to whether the specimens were fresh (control, n=20), cryopreserved and rapidly thawed (RT) at 37$^{\circ}C$ (n=20), or cryopreserved and subjected to controlled, automated slow thawing (ST)(n=20). Cell damage was established using the TUNEL method and the morphological changes were also evaluated. Result: In the group that was rapidly thawed, the expression of TUNEL (＋) cells increased significantly more than in the slowly thawed group. In addition, the endothelial denudation, microvesicles and edema were significant in the rapidly thawed group compared with those changes in the slowly thawed group. Conclusion: Our study suggests that the rapid thawing method may be one of the major causes of cellular damage and delayed rupture in cryopresewed arterial allografts. The expression of TUNEL (＋) cells and structural changes were significantly low in the slowly thawed group, which might have contributed to the improvement of graft failure after transplantation.

• Journal of Plant Biotechnology
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• v.32 no.3
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• pp.151-159
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• 2005

Injury caused by reactive oxygen species (ROS), known as oxidative stress, is one of the major damaging factors in plants exposed to environmental stress. Chloroplasts are specially sensitive to damage by ROS because electrons that escape from the photosynthetic electron transfer system are able to react with relatively high concentration of $O_2$ in chloroplasts. To cope with oxidative stress, plants have evolved an efficient ROS-scavenging enzymes such as superoxide dismutase (SOD) and ascorbate peroxidase (APX), and low molecular weight antioxidants including ascorbate, glutathione and phenolic compounds. To maintain the productivity of plants under the stress condition, it is possible to fortify the antioxidative mechanisms in the chloroplasts by manipulating the antioxidation genes. A powerful gene expression system with an appropriate promoter is key requisite for excellent stress-tolerant plants. We developed a strong oxidative stress-inducible peroxidase (SWPA2) promoter from cultured cells of sweetpotato (Ipomoea batatas) as an industrial platform technology to develop transgenic plants with enhanced tolerance to environmental stress. Recently, in order to develop transgenic sweetpotato (tv. Yulmi) and potato (Solanum tuberosum L. cv. Atlantic and Superior) plants with enhanced tolerance to multiple stress, the genes of both CuZnSOD and APX were expressed in chloroplasts under the control of an SWPA2 promoter (referred to SSA plants). As expected, SSA sweetpotato and potato plants showed enhanced tolerance to methyl viologen-mediated oxidative stress. In addition, SSA plants showed enhanced tolerance to multiple stresses such as temperature stress, drought and sulphur dioxide. Our results strongly suggested that the rational manipulation of antioxidative mechanism in chloroplasts will be applicable to the development of all plant species with enhanced tolerance to multiple environmental stresses to contribute in solving the global food and environmental problems in the 21st century.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1007-1016
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• 2003

Garlic was stored at 4, 8, and $12^{\circ}C$ to investigate the development of green discoloration. Green discoloration developed after 7 day of storage ar $4^{\circ}C$, while it developed after 15 day of storage at 8 and $12^{\circ}C$. The effect of maleic hydrazide fertilization on green discoloration of garlic was not observed. Green discoloration of garlic was accelerated by gamma-radiation treatment. The addition of cysteine did not prevent green discoloration, which decreased the commercial value of the garlic due to the presence of white specks on the surface. When 3% ascorbic acid was added to the garlic, green discoloration developed in 6 and 24 hr at room temperature and $4^{\circ}C$, respectively. The tendency of garlic to discolor was also investigated at various storage temperatures. Discolored garlic stored for 30 day at low temperatures was conditioned at $20{\sim}45^{\circ}C$ for 20 day. The green discoloration of garlic conditioned at 20 and $25^{\circ}C$ did not disappear in 20 day, but disappeared in 20 day when conditioned at $30^{\circ}C$. The L, a, and b values of garlic conditioned at 35, 40, and $45^{\circ}C$ for 4 day were similar to those of normal garlic. Conclusively, our results indicated that the best method for suppressing green discoloration was conditioning discolored garlic at $35^{\circ}C$ for 4 day.

• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.2
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• pp.77-83
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• 2021

Rye (Secale cereal L.) is the most tolerant to abiotic stress including low temperature, drought, and unfavorable soil conditions among the winter cereals. Rye is the rapid growth of early spring results from increasing areas for the use of the forage and green manure in the middle part of Korea. "Jungmo2509", a rye cultivar was developed by the National Institute of Crop Science (NICS), RDA in 2014. It was developed from a cross between "Olhomil", a self-compatible cultivar, and "Synthetic II", a self-incompatible line. "Jungmo2509" is an erect plant type and of a middle size, with a green leaf color, a yellowish-white colored culm, and a yellowish brown-colored, small-size grain. The heading date of "Jungmo2509" was April 23, which was 5 days later than that of "Gogu", respectively. But "Jungmo2509" showed greater resistance to lodging compared to that of the check cultivar, with similar to winter hardiness, wet injury, and disease resistance. "Jungmo2509" was a higher to than "Gogu" in terms of protein content (9.4% and 8.0%, respectively), total digestible nutrients (TDN) (55.7% and 55%, respectively). The seed productivity of "Jungmo2509" was approximately 2.08 ton 10a-1, which was 11% lower than that of the check. Almost all rye cultivars are out-crossing due to genes controlling incompatibility, but "Jungmo2509" is higher seed fertility (56%) than that of Gogu (0%). it has self-compatible genes. "Jungmo2509" is erect in plant type and resistance for lodging. Therefore, "Jungmo2509" can produce uniform seeds for processed grains of human consumption and utilize them as parents for breeding the rye hybrids with high forage yields.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.2
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• pp.149-154
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• 1992

Buckwheat has been a popular favorite food crop in Korea for a long time. The objective of the study was to investigate the effects of climatic conditions and cultural methods on grain yields of summer buckwheat variety Sinnong 1 planted during the spring season in Suwon, Korea from 1989 to 1991. Frost minimum temperature of late April was -0.3$^{\circ}C$ in 1990 being very low as compared with 3.7$^{\circ}C$ of the normal year, and affected early growth of the seedlings emerging from the soil surface. In late May of 1990, the frost minimum temperature was 7.3$^{\circ}C$ being low as compared with 8.8$^{\circ}C$ of the normal year, and also induced cold injury to fertilization and grain filling. Total precipitation 374.5mm of mid and late June, 1990 provided serious damage to the grain filling and maturing buckwheat seeds and along with causing seed sprouting before harvest. However, the climates of 1989 and 1991 were very good for the growth and development of spring-sown buckwheats. When summer buckwheat cultivar Sinnong 1 was planted on April 20, 1989, its highest grain yields 268-292kg /10a were harvested from the plots of seeding rate 8kg /10a, drill seeding and polyethylene film mulching, and the mean grain yield of the plots was 238kg /10a in 1989, but 64.3kg in Suwon, and 40.2kg /10a in Muan in 1990. In 1991 maximum grain yield 277kg /10a was produced from the April 15 planted and vinyl-mulched plot, and 255kg /10a from the April 25 planted and non-mulched plot. Herbicide Alachlor-sprayed plots produced lower grain yields than no weed control and manual weeding plots. Mechanized drill-seeding saved 83～84% in planting hours as compared with manual broadcasting 21.6 hours /ha, and produced 9% more in grain yields from the two-season croppings of mechanized drill-seeding culture being 364kg /10a in total yields per year.

• Food Science and Preservation
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• v.18 no.4
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• pp.442-458
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• 2011

Among Cucubitaceae, melon (Cucumis melo) is one of the most diversified fruits, with various forms, sizes, pulps, and peel colors, In addition, it is a commercially important crop because of its high sweetness, deep flavor, and abundant juice. In the species, there are both climacteric and non-climacteric melons depending on the respiration and ethylene production patterns after harvest. Ethylene is also considered a crucial hormone for determining sex expression, Phytohormones other than ethylene interact and regulate ripening, There are some indices that can be used to evaluate the optimum harvest maturity. The harvest time can be estimated after the pollination time, which is the most commonly used method of determining the harvest maturity of the fruit. Besides the physiological aspects, the biochemical alterations, including those of sweetness, firmness, flavor, color, and rind, contribute to the overall fruit quality. These changes can be categorized based on the ethylene-dependent and ethylene-independent phenomena due to the ethylene-suppressed transgenic melon. After harvest, the fruits are precooled to $10^{\circ}C$ to reduce the field heat, after which they are sized and packed. The fruits can be treated with hot water ($60^{\circ}C$ for 60 min) to prevent the softening of the enzyme activity and microorganisms, and with calcium to maintain their firmness. 1-methylenecyclopropene (1-MCP) treatment also maintains their storability by inhibiting respiration and ethylene production. The shelf life of melon is very short even under cold storage, like other cucurbits, and it is prone to obtaining chilling injury under $10^{\circ}C$. In South Korea, low-temperature ($10^{\circ}C$) storage is known to be the best storage condition for the fruit. For long-time transport, CA storage is a good method of maintaining the quality of the fruit by reducing the respiration and ethylene. For fresh-cut processing, washing with a sanitizing agent and packing with plastic-film processing are needed, and low-temperature storage is necessary. The consumer need and demand for fresh-cut melon are growing, but preserving the quality of fresh-cut melon is more challenging than preserving the quality of the whole fruit.