• Applied Biological Chemistry
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• v.43 no.4
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• pp.236-240
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• 2000

Correlations between mitochondrial respiration, glycolysis activity and overall growth activity of rice (Oryza sativa: cv. Dasan) seedlings during low temperature exposure were studied in order to provide insights into the underlying mechanism for the primary phase of chilling injury in plants. Among cellular membranes involved in energy metabolism, only the mitochondrial inner membrane showed not only physical phase transition at ca. $13^{\circ}C$, as monitored by ESR spin label, but also functional phase transition at the same temperature, as assessed by cytochrome c oxidase activity. The main regulatory enzyme of glycolysis, phosphofructokinase, in situ did not suffer phase transition of its activity at least in the $4{\sim}27^{\circ}C$ range. Low temperature caused a significant accumulation of glucose 6-phosphate (G6P) and fructose 6-phosphate (F6P), which disappeared almost completely on rewarming of the seedlings. Temperature profiles of the steady state levels of G6P and F6P revealed the inflection point appearing at around phase transition temperature of the mitochondrial membrane. The results conform to our previous proposition on the mechanism for the early stage events of chilling injury that the accumulation of glycolytic metabolites in cells due to metabolic imbalance at low temperature gives rise to an excess supply of electrons during rewarming period, which, in turn, results in overproduction of active oxygen in mitochondria.

• Food Science and Preservation
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• v.20 no.2
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• pp.151-157
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• 2013

This study was conducted to investigate the effect of mature stages on quality of Rafito tomatoes (Lycopersicon esculentum Mill.) during storage at low temperature. Tomatoes grown in greenhouse were harvested at three different mature stages (turning, pink, and red), packaged with a 30-${\mu}m$-thick polyethylene film, and then stored at 5 and $10^{\circ}C$, respectively. The changes in firmness, soluble solids content (SSC), titratable acidity (TA), colour, lycopene content, decay, and chilling injury were measured on a weekly basis. After three weeks of storage, chilling injury and decay were found to have individually occurred at 5 and $10^{\circ}C$, respectively. As there was little change in quality at $5^{\circ}C$, it was concluded that red tomatoes could maintain their good quality for two weeks. The normal postharvest ripening was inhibited in the turning and pink tomatoes during storage at $5^{\circ}C$. The turning and pink tomatoes showed improved quality after two-week storage at $10^{\circ}C$. In particular, the turning fruits showed the highest firmness throughout the storage period. Furthermore, the red colour, SSC/TA, and lycopene content of the turning fruits reached the same levels as with the red fruits after two-week storage at $10^{\circ}C$. These results suggest that red tomatoes should be stored at $5^{\circ}C$ to inhibit decay, and that the optimum temperature for early-harvested tomato (turning and pink) is $10^{\circ}C$ for the ripening process after harvest.

• Korean Journal of Weed Science
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• v.32 no.1
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• pp.35-43
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• 2012

The objective of this research was to confirm the difference in physiological responses to environmental stresses such as chilling, high temperature, NaCl, and chemical stress (paraquat) in Protox inhibitor resistant-transgenic rice (MX, PX, and AP37) and its non-transgenic counterpart (WT). Transgenic and non-transgenic rice plants were exposed to a chilling temperature of $5^{\circ}C$ for 1 day or a high temperature of $45^{\circ}C$ for 4 days and allowed to recover at $25^{\circ}C$ for 6 days after the chilling treatment or 8 days after the high temperature treatment. Leaf injury, shoot fresh weight, porphyrin biosynthesis substances, and chlorophyll content were investigated in transgenic and non-transgenic rice at 6 days after 0.5% and 1% NaCl treatments or at 5 days after 0~300 ${\mu}M$ paraquat treatments. No significant difference in leaf injury and shoot fresh weight were observed between transgenic and non-transgenic rice during chilling and recovery. Plant height and shoot fresh weight were also similar between transgenic and non-transgenic rice during the high temperature and recovery period (0~5 days). However, plant height and shoot fresh weight in transgenic rice line MX and PX were lower than in non-transgenic rice at 6 days for recovery. Leaf injury, chlorophyll, and Mg-Proto IX ME contents had no significant difference between transgenic rice and non-transgenic rice after NaCl treatment, but Proto IX content for AP37 and shoot fresh weight for PX and AP37 in 0.5% NaCl treatment were significantly reduced compared with non-transgenic rice. There was no difference in leaf injury and shoot fresh weight when comparing transgenic rice and non-transgenic rice after paraquat treatment. Although transgenic rice and non-transgenic rice showed a little difference at a particular measurement period in certain environmental stresses, there was generally no difference in physiological responses between transgenic rice and non-transgenic rice.

• Journal of the Korean Society of Tobacco Science
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• v.16 no.1
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• pp.64-68
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• 1994

The present experiments were conducted to investigate some of the factors affecting the number of haploids derived from anther culture of Nicotiana tabacum. Anther - donor plants grown under controlled environment room at 3$0^{\circ}C$ yielded more haploid than room at 18, 25 and 26-22-18$^{\circ}C$ in anther culture. Donor plants starved of fertilizer yielded more haploids as compared to those of the well fed with fertilizer in anther culture. Pretreatment of exercised flower bud at 5$^{\circ}C$ was shown to be more effective in anther culture than pretreatment at 7 and 1$0^{\circ}C$, and the optimum temperature and period of pretreatment were 4 or 6 days at 5$^{\circ}C$.

• Korean Journal of Agricultural and Forest Meteorology
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• v.7 no.2
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• pp.148-155
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• 2005

An accurate prediction of blooming date is crucial for many authorities to schedule and organize successful spring flower festivals in Korea. The Korea Meteorological Administration (KMA) has been using regression models combined with a subjective correction by forecasters to issue blooming date forecasts for major cities. Using mean monthly temperature data for February (observed) and March (predicted), they issue blooming date forecasts in late February to early March each year. The method has been proved accurate enough for the purpose of scheduling spring festivals in the relevant cities, but cannot be used in areas where no official climate and phenology data are available. We suggest a thermal time-based two-step phenological model for predicting the blooming dates of spring flowers, which can be applied to any geographic location regardless of data availability. The model consists of two sequential periods: the rest period described by chilling requirement and the forcing period described by heating requirement. It requires daily maximum and minimum temperature as an input and calculates daily chill units until a pre-determined chilling requirement for rest release. After the projected rest release date, it accumulates daily heat units (growing degree days) until a pre- determined heating requirement for flowering. Model parameters were derived from the observed bud-burst and flowering dates of cherry tree (Prunus serrulata var. spontanea) at KMA Seoul station along with daily temperature data for 1923-1950. The model was applied to the 1955-2004 daily temperature data to estimate the cherry blooming dates and the deviations from the observed dates were compared with those predicted by the KMA method. Our model performed better than the KMA method in predicting the cherry blooming dates during the last 50 years (MAE = 2.31 vs. 1.58, RMSE = 2.96 vs. 2.09), showing a strong feasibility of operational application.

• Journal of the Korean Society of Food Science and Nutrition
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• v.6 no.1
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• pp.1-8
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• 1977

The sample persimmons were obtained from the of Yung-am Kun, Korea on October 24, and November 9, 1973. These persimmons were kept at room temperature overnight, then packed and stored on the following day at $0^{\circ}C$ and $85{\sim}100%$ humidity. Seven experimental items were studied : 1. control, 2. packing with excelsior in wooden boxes, 3. packing with rice hull in wooden boxes, 4. packing in bags of 0.03 mm polyethylene membrane, 5. packing in bags of 0.06 mm polyethylene membrane, 6. packing in bags of 0.08 mm polyethylene membrane, 7. packing in sealed desiccators. The dimension of polyethylene bags were $14{\times}28cm$ and three persimmons were packing in each bag. The results are as follows: 1. The persimmons both in polyethylene bags and in desiccators lost only 1 % or less of weight, while in control (1) packing with excelsior (2) or with rice hull (3) the loss was 6-7 % in weight after $2{\sim}3$ months. The persimmons became visibly shriveled and spongy-like in it's texture when it lost 5 % of weight. 2. Carbon dioxide content within the polyethylene bags and desiccators rapidly increased during the early storage period, and reached 5 % (in 0.03 mm polyethylene bags) to 50 % or more (in desiccator) after 1 month. In the polyethylene bags of 0.08 mm and desiccator, the carbon dioxide accumulated to a dangerous level and the persimmon showed physiological damage in a longer storage period. 3. The advance of after-ripening and deterioration of persimmon sealed in the polyethylene bags was slower than that in open bags when moved out to room temperature from the chilling and the polyethylene bags of 0.06 mm retarded the after-ripening most effectively. 4. On the basis of these results, a temperature of $0^{\circ}C$, relative humidity of almost $85{\sim}100%$ and combinations of 5 % oxygen and $5{\sim}8%$ carbon dioxide seem to be the optimum condition for the storage of persimmon (Teabong-Si). The most successful method of storing was to pack them in polyethylene bags of 0.06 mm and then to store them at $0^{\circ}C$.

• Horticultural Science & Technology
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• v.33 no.4
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• pp.501-510
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• 2015

In this study, we investigated the onset and release of endo-dormancy under natural conditions by observing bud break characteristics in 'Fuji' apple trees using water cuttings. Through examinations of bud break rate and days to bud break, we found that the endo-dormancy of 'Fuji' apple tree continues for 70 d from 165 to 255 d after full bloom (DAFB), from late October to early January of the following year. In addition, within 20 d of first bud break, based on a final bud break rate of 60% or more, we able to identify the timing of the changeover from para-dormancy to endo-dormancy, and endo-dormancy to eco-dormancy. Analysis of the chilling requirement during the endo-dormancy period revealed that chilling accumulation up to 255 DAFB to release endo-dormancy amounted to 666 and 517 h based on the CH and Utah models, respectively. Observation of internal changes in the bud during endo-dormancy showed that flower bud differentiation begins from mid-July, and t ime of inflorescence o f the disk f lower is a vailable to f ind. The f lower buds subsequently developed slowly but steadily during endo-dormancy and in the following year in February, the developmental stage of each organ had progressed. Moreover, the flower buds of 'Fuji' apples were mostly healthy during the dormancy period, but some exhibited necrosis of flower primordium, due partial cell damage from the formation of ice crystals rather than a direct effect of the low temperature. Flower buds were formed in both the axillary buds of bourse shoots and terminal buds of spurs, but lower bud differentiation was observed for the terminal buds of spurs at rate of about 65% of total buds, which was directly related to the bud size and shoot diameter.

• Journal of the East Asian Society of Dietary Life
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• v.10 no.3
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• pp.222-228
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• 2000

The experiment was conducted to investigate the physico-chemical characteristics of vacuum and aerobically packed meat from Elk deer weighing 170 $\pm$ 10kg of 28 to 30 months old, chilled at 4$^{\circ}C$for 10days. The moisture content, crude protein, crude fat and crude ash in deer loin were 74.46%, 22.11%, 1.27% and 1.13%: the leg parts had 75.47%, 22.68%, 1.58% and 1.27%, respectively. The decrease in moisture content was greater in aerobic packaging than in vacuum packaging. The lysine content of loin and leg parts were 2,380mg% and 2,270mg% and the glutamate content of loin and leg parts were 4,145mg% and 3,987.5mg% respectively. On the whole, the loin contained more amino acids than leg part. Of the mineral contents, phosphorus, potassium and sodium were present in large amounts and mineral content was decreased with longer chilling period. The leg parts contained more potassium, sodium, phosphorus, zinc, magnesium and calcium than loin parts. In conclusion, vacuum packaging is considered more advantageous in preventing meat color change and microbial deterioration for consumers interest.

• The Journal of Korean Obstetrics and Gynecology
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• v.20 no.3
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• pp.238-245
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• 2007

Purpose: In postpartum period, women are very weak and liable to various diseases. So postpartum care is very important. But excessive heating and sweating cause postpartum diseases. Methods: The patient in this case, 37 years-old female was in Kyunghee University East-West neo medical center for 8days(27th/Oct/2006 - 3rd/Nov/2006). Her chief complains when she was admitted in the hospital were sweating, chilling, and mild dizziness. These symptoms were caused by excessive heating and sweating. We thought that her condition was deficiency of Qi. After giving her the therapies with herb medicine, acupuncture and moxibustion, her symptoms got almost disappeared and her condition got better. Results: After the oriental medical treatment, the clinical symptom of postpartum disease was improved. Conclusion: This case study shows that excessive heating and sweating cause postpartum diseases and the oriental medical therapy is effective in treating postpartum disease. And the guideline of postpartum care is needed.

• International Journal of Industrial Entomology and Biomaterials
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• v.25 no.2
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• pp.159-162
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• 2012

The Chinese windmill butterfly, Atrophaneura alcinous, is an important butterfly for exhibition in butterfly garden. The objective of this study was to determine the effect of temperature on A. alcinous in the laboratory. Development of A. alcinous reared on leaves of Aristolochia contorta was investigated at five constant the laboratory condition (20, 22.5, 25, 27.5 and $30^{\circ}C$) and at relative humidity of 60% with a photoperiod of 14:10 (L:D). Temperatures have been suggested as an important determinant of developmental rate, lifespan and mortality in invertebrates. As the temperature increased, the length of the developmental period gradually decreased. The developmental time (pupation) from egg hatching to pupation was respectively 25.8, 23.6, 19.6, 15.5, and 12.9 days at the temperatures of 20, 22.5, 25, 27.5 and $30^{\circ}C$. And pupation was respectively 40.0, 30.0, 63.4, 50.0, 23.3% at the temperatures of 20, 22.5, 25, 27.5 and $30^{\circ}C$. The developmental threshold temperature estimated for egg-to-pupae was 10.8, with a thermal constant of 230.4 degree-days. Therefore, the optimal developmental temperature for A. alninous was determined to be $25^{\circ}C$. To compare the effects of the total duration of chilling on the termination of diapause, larvae were subjected to a temperature of $8^{\circ}C$ from 60 to 120 days. The rate of termination of diapause was significantly higher at 60 days compared to other incubation period.