• Korean Journal of Childcare and Education
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• v.8 no.5
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• pp.231-252
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• 2012

This study examined the influence of job stress and personal resources (hardiness, optimism) of child counselors on their burnout and work engagement. For the study, 171 child counselors were surveyed. The main effects of job stress and personal resources on burnout and engagement were tested using hierarchical multiple regression analysis. The findings of this study were as follows: First, the study showed that both job stress and personal resources were related to burnout and work engagement. Specially, job stress was more closely related to burnout, whereas personal resources were more closely related to work engagement. Second, hardiness as personal resources reduced the level of burnout in child counseling. Third, although job stress negatively affected the level of work engagement, personal resources (hardiness, optimism) were relevant predictors of work engagement. Hardy and optimistic child counselors are less likely to experience burnout, they are more likely to experience vigor, dedication, and absorption on their job. Based on the results of this study, the practical implications for child counselors were discussed.

• Journal of Korean Society of Forest Science
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• v.99 no.2
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• pp.244-250
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• 2010

The aim of this study was to investigate relationship among seed viability and enzymes activities involved in scavenging reactive oxygen species (ROS), especially, superoxide dismutase (SOD), glutathione reductase (GR), and catalase (CAT). In other respects, osmopriming has been demonstrated to reinvigorate aged seeds. Various viabilities of seeds that were ranged from 80 to 100% of germination rate could be produced using osmopriming and accelerated aging treatments. Priming treatment of Pinus thunbergii seeds for 3 days at $15^{\circ}C$ with a polyethylene glycol solution at -1.2 MPa improved their subsequent germination at $25^{\circ}C$. Accelerated aging (3, 6, 9, and 12 days at $41^{\circ}C$ and 100% relative humidity) decreased seed germination percentage depending on aging treatment duration. Electrolyte conductivities of seeds were measured as assay of membrane integrity. The conductivity from electrolyte leakage of P. thunbergii seed was also correlated with seed germinability. Conductivity for control seeds that had 95% of germination percentage was 3.48 ${\mu}S\;g^{-1}$, but jumped as doubled (7.98 ${\mu}S\;g^{-1}$) in 12-day-aged seed that had 80% of germination percentage. Our results demonstrate that aging of P. thunbergii seeds is associated with changes in the electrolyte leakage, lipid peroxidation, and antioxidant defense system. Priming of aged seeds progressively restored the initial germinative ability and resulted in a marked decrease in the levels of MDA and conductivity of seed leachate. These effects of priming were also well recovered of GR and CAT activities in aged seed. The improved seed quality by priming treatment appears at least partly attributable to reduced lipid peroxidation, resulting from enhanced antioxidative enzyme activities that are suggesting the antioxidant defense systems play a key role in seed vigor.

• Journal of Plant Biotechnology
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• v.6 no.4
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• pp.221-227
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• 2004

Protocol was established for production of virus free healthy seeds using meristem ($0.3-0.5\;\cal{mm}$ in size) culture and field management under net house condition in tomato. The isolated meristem was found well established in MS liquid medium containing $0.1\;\cal{mg}\;1^{-1}\;of\;GA_3$. For shoot and root development either from primary meristem or from nodal segment of meristem derived plants, semisolid MS medium having $0.5\;\cal{mg}\;1^{-1}$ of IBA was found most effective. The elimination of the studied viruses (ToMV, CMV, ToLCV) in meristem-derived plants was confirmed by DAS-ELISA test. For field management of the virus eradicated meristem-derived plants, use of net house was found very effective measures to check viral vector visit and eventually infection. The meristem-derived plants were vigor and high yielder than the native seed derived plants and produced healthy seeds. Due to stop vector visit, no viral symptoms were observed in both $R_1\;and\;R_2$ plants cultivated in net house condition. Starting of viral infestation was observed in $R_2$ generation when they were planted in open house condition without control of vector visit. Therefore, for management of viral diseases, use of virus free meristem derived plantlets and their subsequent cultivation in soil under net house condition without using any vector killing insecticide can be recommended for producing healthy seeds in tomato. The developed protocol for environmentally healthy tomato seed production in Bangladesh may be used in the countries having similar tropical like environment conducive for viral vector visit.

• Journal of Forest and Environmental Science
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• v.30 no.1
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• pp.120-125
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• 2014

Halophytes are plants of saline habitats that grow under conditions that may vary in extremes of temperatures (freezing to very hot), water availability (drought to water logging) and salinity (mild to almost saturation). Halophytes may also face sudden micro-environmental variations within their habitats. In this study, we examine some of the factors that determine the ability of seeds of Artemisia fukudo to germinate when conditions are optimal for seedling growth and survival. Germination percentage was the highest at 77.5% when treated in 0% seawater and seedling growth was best in 0% seawater plug cell tray. Physiological quality (chlorophyll contents) and mean germination time were best in the condition in which seeds were treated with 0% seawater (control). Germination performance index in the control group showed the highest value to 3.8. Seedling growth, seedling vigor index in the length of seedling growth andthe relative growth rate were the highest values of 0.76 cm, 1.43, 0.0099, respectively.

• Journal of Forest and Environmental Science
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• v.30 no.1
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• pp.62-70
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• 2014

The principle purpose of this research is to figure out whether the inhalation of Wood Essential oil (Chamaecyparis obtusa) affect not only human beings' concentration for surroundings but also change as to status of feelings. total number of subjects for this experimental are determined to be 66 (men 44 and women 22) among 85 adults who agreed to participate in this experiment after excluding 19 participants who were not able to smell scent due to flu and nasal inflammation. After both experimental group and control group being measured referring to their status of mood such as concentration, depression, vigor, fatigue, confusion, tension and anger, the experimental group is offered to get a piece of cotton that includes Wood Essential oil and they are asked to inhale it for 5 min. On the other hand, control group is offered to wait for the experimental group finishing inhaling wood Essential oil for 5 min. After 5 min, the status of mood from both groups were measured again. simultaneously, I conducted a survey targeting experimental group to see what their preferences are like regarding scent of wood essential oil. The experiment shows that the status of experimental group's concentration is improved about 0.94 point when compared to control group's. Moreover, Total mood disturbance is lower than control group's. Therefore it is proved that the inhalation of wood Essential oil alleviates overall status of mood. according to the analyses result of favor to scent for wood essential oil from experimental group, some of them who were positive got much better improvement when it comes to concentration and far more relieved on their feelings than those who weren't. Based from this result, it is definitely confirmed that there is a Phytoncide's psychophysiological effect which transcends the Placebo Effect generated by Phytoncide's positive image.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.5
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• pp.373-380
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• 2004

The production of sweet (su) and super sweet corns (sh2) has been economically feasible in Korea in recent years. Major factors limiting super sweet corn production are low germination and low seedling vigor. Since seed quality is closely related to seed maturity, the optimum harvest time for the seed production of sweet and super sweet corns was studied and the quality of seeds with varying maturities was investigated in 2001 and 2002 cropping seasons. The parents of the sweet corn seeds were Hybrid Early Sunglow and 'Golden Cross Bantam 70' and those of super sweet corn were Xtrasweet 82 and 'For­tune'. Seeds were harvested at 21, 28, 35, 42, 49, and 56 days after silking (DAS). As the seeds developed, seed weight of sweet corn increased and the seed moisture content decreased faster than that of super sweet corn. Germination rates of sweet corn seeds harvested 21 and 28 DAS at $25^{\circ}C$ and emergence rates in the cold soil test were significantly lower than those of seeds harvested after 42 DAS in both years. Although the germination rates of super sweet corn seeds with varying maturities showed similar patterns as sweet corn seeds at $25^{\circ}C$, the emergence rate of super sweet corn seeds in cold soil test continuously increased with seed maturity. This suggests that seed quality of super sweet corn should be tested in a cold soil test to estimate field emergence. As the seeds developed, leakage of total sugars and electrolytes from the both sweet and super sweet corn seeds decreased up to 42 or 49 DAS. The $\alpha-amylase$ activities of both sweet and super sweet corn seeds increased with seed maturity from 21 to 35 or 49 DAS depending on genotype and year. The optimum harvest time for the seed production of sweet corn was 42 DAS and 49 DAS for super sweet corn considering emergence rate and plumule dry weight in the cold soil test, leakage of sugars and electrolytes from the seeds, and $\alpha-amylase$ activity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.1
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• pp.25-29
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• 2004

The responses of soybean seeds were evaluated to accelerated aging and gamma irradiation with regard to germination, seed leakage, seed leachate component and dry weight of hypocotyl and primary root of the germinating seed. Accelerated aging significantly reduced the final germination rate while gamma irradiation increased the final germination rate. Furthermore, the interactive effects occurred that the final germination rate of 5-day aged seeds increased considerably in response to 4 Gy of gamma irradiation. The extent to which the electrolyte was leaked from the seeds (conductivity) was significantly affected by accelerated aging and showed a close negative correlation with the germination rate. Gamma irradiation, however, did not significantly affect the electrical conductivity of seed leachate. The accelerated aging significantly increased the concentrations of the particular electrolytes leaked from the seeds while the gamma irradiation did not affect those concentrations. Of the electrolytes leaked from the seeds, Ca and Mg showed relatively lower concentrations while K showed greater concentrations than others. Moreover, N and P showed similar responses to aging treatment. Aging treatment significantly affected dry weight (DW) of hypocotyls and primary root. Also, gamma irradiation decreased DW of hypocotyls and primary root, particularly for 8 Gy associated with 5 days aging treatment. The data were discussed in terms of the relationships of seed vigor with aging treatment and gamma irradiation.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.192-192
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• 2017

Direct-seeding cultivation of rice is increasing in Asia instead of transplanting system, because of its lower cost and operational simplicity. Low-temperature germinability (LTG) and anaerobic germinability (AG) are important characters for breeding of varieties for wide-spread adoption of direct-seeding cultivation in rice. This study was performed to characterize LTG and AG of seven rice varieties and identify varieties with strong germinability on both low-temperature and anaerobic conditions. The mean germination rate and germination vigor of seven varieties were 51.7% and 6.0 under low-temperature condition, respectively. Among these varieties, Cheongcheongjinmi and Hwanggeumnodeul had the highest germination rate of 80%, indicating that Cheongcheongjinmi and Hwanggeumnodeul have a good LTG. In anaerobic conditions, the germination rate and coleoptile length for all varieties were 47.6% and 3.2 cm, respectively. Of them, the highest germination rate and coleoptile length were observed in Subo and Hopum, respectively, suggesting that these two varieties are tolerant to anaerobic during germination stage. Molecular characterization by SDS-PAGE revealed that the protein patterns differed at 50 kDa, 40 kDa, and 22 kDa between low-temperature and anaerobic conditions. Varieties identified as good LTG or AG in this study may be used for developing new direct-seeding rice cultivars through pyramiding these traits in the breeding program.

• The Plant Pathology Journal
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• v.19 no.3
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• pp.181-183
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• 2003

Corky root symptoms caused by Pyrenochaeta lycopersici were observed on the roots and stem base of tomato plants in Korea. Symptoms on infected plants typically appeared as stunting and generally lacking vigor, and infected plants die back from the foliage tips after fruits have set. Brown lesions appearing with bands around the roots were characteristic symptoms of the disease. The lesions become swollen and cracked along the length of the root with corky appearance. Based on cultural and morphological characteristics, the fungus from the diseased plants was identified as Pyrenochaeta lycopersici. Pycnidia were solitary, globose to subglobose, brown to black, darker around the neck region, and measured 173-215 $\mu\textrm{m}$ in diameter with septate setae up to 102-132$\times$6.5 $\mu\textrm{m}$. Conidia were hyaline, unicellular, and 4.2-4.7$\times$l.5-2.0 $\mu\textrm{m}$ long. Optimum temperature for mycelial growth of the p. lycopersici isolates ranged from $20^{\circ}C$ to $25^{\circ}C$. Fifteen isolates off lycopersici were tested for pathogenicity to susceptible and tolerant cultivars of tomato plants by artificial inoculation. Three isolates of P. lycopersici induced typical corky root discoloration on susceptible tomato cultivars but not on tolerant tomato. This is the Erst report in Korea of tomato corky root disease caused by P. lycopersici.

• Research in Plant Disease
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• v.12 no.3
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• pp.294-297
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• 2006

Leafy lettuce(Lactuca sativa L.) is one of the most important vegetable crops in Korea, cultivated throughout the year in greenhouses. During the autumn of 2005, powdery mildew of lettuce that is a new disease caused by Podosphaera fusca occurred in several plantings grown in plastic houses near Suwon in central Korea. Further survey on commercial fields of the plant in central and southern Korea revealed its widespread occurrence and severe losses. Infections occur on upper part of mature leaves often cause leaf distortions, withering, and reduced vigor and growth. Among 184 greenhouses surveyed 121 were infested by the disease and 52 showed over 10% infection rate. Yields were greatly reduced by the disease reaching only 59% compared to healthy plants. About 60% leaves of infected plant were not marketable and fresh weight of the leaves was 73.6% compared to healthy leaves. Total yield of the greenhouses infested by the disease ranged from $100{\sim}140kg$, while it was 260 kg in a non-infested greenhouse at one time harvest. Since the disease represents a threat to safe cultivation of leafy lettuce in Korea, environmentally-friend control strategies should be urgently developed.