• Journal of Bio-Environment Control
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• v.10 no.1
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• pp.36-41
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• 2001

This experiment was carried out to investigate temperature distribution in the double layer plastic greenhouse and chilling injury to watermelons grown during a cold season. Temperatures on eastern and western sides were about 6.2% and 14.7%, respectively, lower than that of central section in a south-north oriented greenhouse. Daily mean temperature in the northern part was about 1-2$^{\circ}C$ higher than that in the southern part of the greenhouse. In terms of vertical temperature distribution inside the greenhouse, temperature at ground surface was approximately 1$^{\circ}C$ lower during the day and 0.5$^{\circ}C$ higher during the night than that in the upper part, 2m from the ground surface. Leaf mould medium kept higher ground temperatures as compared to sandy soil, red clay soil, and in the northern and southern sides as compared to the central part of the greenhouse. A symptom of chilling injury on leaves was upward curling, followed by chlorosis and necrosis. A severe symptom of chilling injury to plants was the breakdown of vascular bundles. Root growth was more susceptible than stem or leaf growth to low temperatures. At 3$0^{\circ}C$, main and lateral roots grew vigorously, while lateral root growth was inhibited at 22$^{\circ}C$ and root growth was stopped at 14$^{\circ}C$ and 6$^{\circ}C$. Small and puffy fruits with dark green surface were produced at low temperatures. In cold season cultivation of watermelons, it is suggested that plants be transplanted in the central part and train to sides of the greenhouse in order to reduced chilling injuries.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.14
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• pp.97-109
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• 1973

1. The relatively lower prehardening temperature was more effective on increase of the hardiness of the intermediately hardy varieties than the higher one but either the extremely hardy or nonhardy varieties did not respond to the temperature as much as the intermediate types. 2. Five degree Centigrade was generally more favorable than $2^{\circ}C$ on hardening of the plants, especially when frozen at higher temperature for shorter duration. 3. It appears that photoperiod during prehardening and hardening did not play so important role as temperature on the hardiness. 4. The higher the soil moisture content, the higher the frost injury occurred. 5. Application of nitrogen increased markedly the hardiness and % DM of the plants. Percentage of dry matter of young seedlings might be used as an easy and rough criterion for evaluating hardiness since there was a highly significant regression of varietal frost injury on the %DM. 6. Four days appeared to be enough for hardening of plants although the plants increased gradually the hardiness as duration of hardening extended. Dehardening of the plants at relativity higher temperature took place rapidly within one to four days. 7. Under this controlled environment, freezing at about $-8^{\circ}C$ for 24 hours seemed the best for the purpose of evaluating the hardiness to low temperature. 8. It is believed that assessment of frost injury should be done at least one week after freezing. Some varieties showed strong ability to recover from the damage as recovery period was extended. 9. As a whole, Cd 80 and 83 were the most hardy and followed by Cappelle and Maris Otter. Four. winter oats varieties and Jufy I belonged to the intermediate type while the other three spring varieties were nonhardy at all. Peniarth was comparable with Maris Otter in hardiness. S 147 appeared the least hardy among the winter oats varieties. 10. It is evident that water-soluble carbohydrate content is associated with the hardiness to some extent but not primary factor involved in hardiness.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.3
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• pp.201-210
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• 1990

This study was carried out to determine the effect of mixture of hymexazole and metalaxyl(Tachigarace) on the growth and reducing low temperature injury in rice seedlings. The amount of mixture of hymexazole and metalaxyl (Tachigarace) applied to reduce low temperature injury was 0, 9, 18 and 36mgr per pot (5${\times}$15${\times}$10cm) by soil incorperation befor sowing. Aging seedling was investigated on the growth responses by the application of 0.36gr mixture of hymexazole and metalaxyl (Tachigarace) per tray (30${\times}$60${\times}$3cm) after cutting of leaf at 35 day-old seedling. Rice seedlings treated with mixture of hymexazole and metalaxyl (Tachigarace) were better in the growth of top and roots, dry weight, erecting and rooting abilities than untreated seedlings. The effective amount of mixture of hymexazole and metalaxyl (Tachigarace) to increase erecting and rooting abilities was 18 mgr per pot. Under low temperature treatment, 12$^{\circ}C$, the leaf discoloration and dead leaf percent of rice seedlings were markedly decreased in the seedlings treated with mixture of hymexazole and metalaxyl (Tachigarace) as compared with untreated seedlings. The more amount of mixture of hymexazole and metalaxyl (Tachigarace) upto 36mgr per pot, the more effective on the low temperature injury in the seedling. The effect of mixture of hymexazole and metalaxyl (Tachigarace) to reduce low temperature damage in rice seedlings was mainly due to decreasing less physiological activities on the expanding leaf area and rooting, transpiration, stomatal diffusion and chlorophyll content of the leaves and oxygen consumption of the roots. Plant height, top dry weight and leaf area of aging seedlings were increased with mixture of hymexazole and metalaxyl (Tachigarace) treatment and leaf cutting as compared with untreated seedling and intact leaf, respectively. The ratio of missing hill of aging seedling was increased with increasing the period of growing seedling and was decreased due to leaf cutting, whereas the effect of mixture of hymexazole and metalaxyl (Tachigarace) application was not observed. Rooting ability of aging seedlings was decreased with lengthening of the period of raised seedling and was increased with mixture of hymexazole and metalaxyl (Tachigarace) treatment and leaf cutting.

• Journal of Practical Agriculture & Fisheries Research
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• v.23 no.1
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• pp.67-80
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• 2021

We analyzed the effect of planting site (elevation: high, middle, low) and temperature condition of orchard on the frost injury occurrence and storage characteristics of persimmon (Diospyros kaki cv. 'Fuyu) fruits under an early fall frost at two orchards, Changwon (A) and Changnyeong (B), Gyeongsangnam-do Korea. Also, the fruits picked at Nov. 5 and Nov. 20 were MA stored to investigate the quality and chilling injury of fruits. On 2-way factor analysis, both planting elevation and orchard factor had not a significant effect on fruit characteristics (weight, firmness, soluble solid), while planting elevation factor did on the skin color (hunter 'a')(p<0.05). A fruit skin coloration at orchard A was faster than that at orchard B. At low elevation of orchard B, 2% fruits were frost injured at harvest season. On LDPE film MA storage with the fruits harvested at Nov. 5 and Nov. 20, the fruits at orchard A had higher fruit firmness than those of orchard B during storage. In addition, the 73% (orchard A) and 85%(orchard B) fruits harvested at Nov. 5 showed no chilling injury 80 days after storage. However, At harvest of Nov, 20 (after incidence of frost), only the 14% fruits of orchard B had no the chilling disorder 80 days after storage, even though 76% fruits at orchard A did.

• Applied Biological Chemistry
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• v.34 no.2
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• pp.162-167
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• 1991

In an attempt to explore the mechanistic aspects of chilling injury in plants and their defensive measures against the low temperature stress, the time sequential measurements of pyruvate, superoxide radicals$(O_{\overline{2}})$ and antioxygenic enzymes during whole period of injury-inducing treatment were performed using mostly rice seedlings. Pyruvate was substantialy accumulated in leaf tissues during the exposure period to $5^{\circ}C$ of the seedlings ; the relative extent of the accumulation was increased with increasing time of the cold treatment. When the cold-treated plants were translocated to ambient temperature$({\sim}25^{\circ}C)$, the accumulation started to dissipate, concomitantly accompaning a remarkable increase in the $O_{\overline{2}}$ level of tissues. Superoxide dismutase(SOD) and catalase were also activated during post-chilling period, although they showed a considerable lag time for activation. In contrast, glutathione peroxidase, another antioxygenic enzyme in cells, was not activated at all by preceding cold treatment of plants. The uptake of exogenous $O_{\overline{2}}$ by the roots of rice seedlings resulted in increase in the activities of SOD and catalase in root tissues. The supply of $H_2O_2$ to plan st brought about the activation of catalase in situ, while failing to exert any effect on the activation state of glutathione peroxidase. The results obtained in this work suggest that pyruvate accumulation in cells is the direct cause of the overproduction of $O_{\overline{2}}$ and thereby other toxic activated oxygen species, and that SOD and catalase may play a crucial role in the protection of plant cells against active oxygen-mediated chilling injury.

• Journal of Bio-Environment Control
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• v.21 no.1
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• pp.50-56
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• 2012

This study was conducted to extend the postharvest life of eggplant ($Solanum$ $melongena$ L.) by modified atmosphere packaging using a OPP bag with 1-MCP to evaluate the alleviation effects of that treatment on external chilling injury during at low temperature. 1-MCP treatment at the level of $1.0{\mu}L{\cdot}L^{-1}$ were very effective in delaying the progress of surface bronzing of eggplant during 10 days of storage at $8^{\circ}C$, but not significant at $1^{\circ}C$. Also, the treatment of 1-MCP at the levels of $0.1{\sim}1.0{\mu}L{\cdot}L^{-1}$ are beneficial to complement low temperature storage and maintain quality indices such as higher firmness and lower weight loss than untreated control even at a critical low temperature 4 to $8^{\circ}C$. The treatment of carbon dioxide using dry ice (DI, 5 g/3 fruits) significantly promoted chilling injury of eggplant stored at $4^{\circ}C$, symptoms were appeared from 3 days after treatment and combination treatment of 1-MCP did not block the development of chilling injury symptom. Meanwhile, single treatment of $CO_2$ absorber (CA, 5 g/3 fruits) or combination treatment with 1-MCP at the level of $1.0{\mu}L{\cdot}L^{-1}$ prevented effectively the external and internal chilling injury at $4^{\circ}C$ during 6 days and 15 days of MAP storage, respectively. Results suggest that 1-MCP and carbon dioxide absorber treatments delay fruit deterioration and are beneficial to broaden storage temperature of eggplant fruits.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.s02
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• pp.34-44
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• 1989

The stability of rice cultivation in Korea is largely depended on climatic conditions, especially, low temperature at the period of early growth stage and after heading. The improvement of cold tolerant varieties and appropriate cultural practices in rice are very effective to minimize the cold damage. This paper is summarized the mechanism and counterplans of cold injury of rice plants. The paddy area having commonly cold injury in Korea is approximately 15, 522ha in 1,709 sites on the national scale. The cold damage at seedling stage in nursery bed appeared to poor germination, leaf discoloration, dead seedlings and seedling rot ect.. At the vegetative stage, the decreased tiller number due to poor rooting and the delayed heading caused by slow growth and panicle differentiation are commonly showed. The cold injury at early reproductive stage appeared to the degeneration of spikelets and rachis - branches, while that at meiosis stage showed to increased sterility due to poor development of pollen and shortened panicle length with delaying heading, therefore the grain yield is largely decreased. The cold damage at heading and ripening stages showed to poor pollination and fertilization, low panicle exsertion, poor grain filling and finally grain quality became low. To minimize the cold injury to rice plants by low temperature, following counterplans would be recommonded ; Improvement of the cold toelrant rice varieties for the regions of midmountains and alpines. Raising healthy seedlings at upland nursery beds and by using of growth regulators such as ABA, Fuchiwang and Tachiace. Soil improvement and organic matter application to reduce cold damage by increasing water and fertilizer holding capacities in the paddy field having commonly cold water and in the place where cold damage is regularly occurred. Appropriate fertilization for raising healthy rice plants to tolerate under low temperature condition. Water management to increase water temperature in the paddy such as depth watering, round channels and polyethylene tubes around the field. Establishment of the optimum cultivation time of rice based on minimum, mean and maximum temperatures at different regions with appropriate rice varieties.

• Korean Journal of Agricultural Science
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• v.41 no.2
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• pp.75-83
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• 2014

Recently, a quick drop of air temperature in plastic film houses by adverse weather conditions leads to the occurrence of low temperature damages to growing crops. Chilling injury, defined as a variety of growth restriction occurring below the optimal temperature, is one of environmental factors strongly affecting crop growth and yield. Low temperature causes the restricted evapotranspiration, reduced mineral uptake (P > K > $NO_3{^-}$), and an increase in electrolyte leakage such as K. Despite being different with plant species, an accumulation of soluble carbohydrates such as glucose, fructose, sucrose and starch under chilling condition is well known. A variety of environmental stresses are known to cause oxidative damage to plants either directly or indirectly by triggering an increased level of production of reactive oxygen species (ROS), and, to combat the oxidative damage, plants have the antioxidant defense systems comprising of enzymes, SOD, POD, CAT, GPX and APX, and non-enzymes, ascorbate, gluthathione, ${\alpha}$-tocopherol, phenolic compounds, carotenoid and flavonoids. The aim of this review is to provide basic information to build chilling-indicators and optimal nutrition management under adverse temperature conditions as broadly considering mineral uptake, carbohydrate metabolism and antioxidative defense system.

• Applied Biological Chemistry
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• v.15 no.3
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• pp.187-192
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• 1972

The qualitative and quantitative changes in RNA in terms of RNase activity of rice plants subjected to the chilling temperature were studied. The total RNA level increased at the early stage and thereafter decreased continuously while the progress of the chilling injury. The change of total RNA was mainly dependent upon the change of ribosomal RNA with soluble RNA less changed. Parallelism between total RNA level and RNase activity was observed at the early stage of chilling injury, while the inverse relationship of RNA RNase was seen in the later stage. Our observations indicate that synthetic function of RNase may be more closely related to ribosomal RNA than soluble RNA.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.22 no.2
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• pp.23-26
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• 1977

In order to test cold tolerance of rice plants 16 varieties were treated at day/night temperature of 10/5$^{\circ}C$ at the 2nd, 4th, and 6th leaf stages. Indica$\times$japonica varieties were more sensitive to low temperature than a japonica variety. Among indica$\times$japonica varieties, "Tongil", "Suweon ＃251", and "Suweon ＃277" were less sensitive to low temperature compared to other indica$\times$japonica varieties tested. The 4th leaf stage was more sensitive to low temperature than 2nd and 6th leaf stages. than 2nd and 6th leaf stages.