• Journal of The Korean Society of Agricultural Engineers
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• v.61 no.5
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• pp.23-31
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• 2019

Crop response to weather and internal water pressure changes is more sensitive to crop water stress than soil water content. Recently, its implementation to optimal irrigation scheduling has been receiving much attention. This study was conducted to determine and compare the theoretical crop water stress index (CWSI) using meterological data and canopy temperature collected from three different irrigation treatments, which were Tr-1 plot (rainfed), Tr-2 plot (50% of daily evapotranspiration (ET) irrigated) and Tr-3 plot (75% of daily evapotranspiration (ET) irrigated). The readings of canopy temperature and CWSI were significantly different among irrigation treatment schemes. The average canopy temperatures and CWSIs of Tr-1 and Tr-3 plots were $34.6^{\circ}C$ and $32.6^{\circ}C$, 0.79 and 0.64, respectively. Solar radiation had the biggest correlation with CWSI (R=0.68) which was followed by wind speed, relative humidity and air temperature. Overall, the findings of this study indicated that canopy temperatures and CWSIs could be further used for irrigation scheduling for crop growth.

• Korean Journal of Agricultural and Forest Meteorology
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• v.15 no.3
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• pp.130-144
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• 2013

In this study, we examined the effect of high temperature of urban area on the physiological response of apple tree including the photosynthesis, shoot growth, and fruit quality of 'Fuji'/M.9 apple trees planted at Daegu urban area (DUA) and Gunwi rural area (GRA) for 2 years (2009-2010). During the apple growing season (April-October), the average air temperature of DUA was about $3.0^{\circ}C$ higher than that of GRA and the total rainfall of DUA was 130 mm more than that of GRA. During fruit enlargement stage (June-August), the number of days that recorded daily mean temperature of over $30^{\circ}C$ were ten on DUA in 2010, but there was no day when such temperature was experienced in 2009. Average air temperature of DUA during the maturation stage (September-October) was $19.8^{\circ}C$, which was $4.0^{\circ}C$ higher than that of GRA. The higher temperature of over $30^{\circ}C$ during fruit enlargement stage decreased the photosynthetic rate, shoot growth, fruit weight, and soluble solid content of 'Fuji'/M.9 apple tree. The moderate temperature of about $20^{\circ}C$ during maturation stage increased the photosynthetic rate and soluble solid content of 'Fuji'/M.9 apple tree, but decreased fruit red color. In regional comparison with GRA, photosynthetic rate of DUA was changed from lower before rainy season to higher after rainy season. Fruit weight was higher in DUA than that of GRA. However, fruit weight between DUA and GRA did not show the difference when accumulated days that recorded daily maximum temperature over $35^{\circ}C$ of DUA was increased. Compared to the GRA, soluble solid content of DUA was higher, but fruit red color of DUA was less. These results indicate that the poor red coloring is the most problematic in 'Fuji'/M.9 apple tree by global warming and urbanization.

• Journal of Korean Society of Forest Science
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• v.102 no.3
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• pp.420-427
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• 2013

This study was conducted to analyze growth characteristics and adaptability of poplar clones under the treatment of liquid pig manure. The average of survival rate was 33% better at control than the treatment under age of 5 years. But, tree height and DBH growth were higher at the treatment than control. Populus euramericana 'Eco28' showed the highest survival rate (97.9%) under the treatment. P. euramericana 'Eco28' and P. deltoides hybrid 'Dorskamp' could be selected as superior clones for height and DBH growth under the liquid pig manure treatment. The above-ground biomass production was also investigated when the poplar clones were 5 years old. The aboveground biomass under the liquid pig manure treatment was, on average. 52.6 ton/ha, which was 80% higher than control (29.1 ton/ha). P. euramericana 'Eco28' (73.6 ton/ha) and P. deltoides hybrid 'Dorskamp' (71.1 ton/ha) showed superior biomass production than other clones at the treatment of liquid pig manure. Based on survival, growth and demage traits, the adaptability of poplar clones to liquid pig manure treatment was estimated. P. deltoides hybrid 'Dorskamp' and P. euramericana 'Eco28' showed better adaptability to the treatment. P. nigra ${\times}$ P. maximowiczii '62-10' and P. koreana ${\times}$ P. nigra var. italic 'Suwon' were identified as poor adaptability clones.

• Plant Biotechnology Reports
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• v.4 no.2
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• pp.139-148
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• 2010

Jatropha curcas L. (Physic nut) is a commercially important non-edible oil seed crop known for its use as an alternate source of biodiesel. In order to investigate the morphogenic potential of immature embryo, explants from four developmental stages were cultured on medium supplemented with combinations of auxins and cytokinins. It was found that the size of embryo is critical for the establishment of callus. Immature embryos (1.1-1.5 cm) obtained from the fruits 6 weeks after pollination showed a good response of morphogenic callus induction (85.7%) and subsequent plant regeneration (70%) with the maximum number of plantlets (4.7/explant) on Murashige and Skoog's (MS) medium supplemented with IBA (0.5 $mg\;l^{-1}$) and BA (1.0 $mg\;l^{-1}$). The above medium when supplemented with growth adjuvants such as 100 $mg\;l^{-1}$ casein hydrolysate + 200 $mg\;l^{-1}$ L-glutamine + 8.0 $mg\;l^{-1}$ $CuSO_4$ resulted in an even higher frequency of callus induction (100%). Plant regeneration (90%) with the maximum number of plantlets (10/explant) was achieved on MS medium supplemented with 500 $mg\;l^{-1}$ polyvinyl pyrrolidone + 30 $mg\;l^{-1}$ citric acid + 1 $mg\;l^{-1}$ BA + 0.5 $mg\;l^{-1}$ Kn + 0.25 $mg\;l^{-1}$ IBA. It was observed that plantlet regeneration could occur either through organogenesis of morphogenic callus or via multiplication of pre-existing meristem in immature embryos. The age of immature embryos and addition of a combination of growth adjuvants to the culture medium appear to be critical for obtaining high regeneration rates. Well-developed shoots rooted on half-halfstrength MS medium supplemented with 0.5 $mg\;l^{-1}$ IBA and 342 $mg\;l^{-1}$ trehalose. The rooted plants after acclimatization were successfully transferred to the field in different agro-climatic zones in India. This protocol has been successfully evaluated on five elite lines of J. curcas.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.3
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• pp.722-728
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• 2005

The DNA topoismerase I inhibitor ${\beta}-lapachone$, the product of a lapacho tree (Tabebuia avellanedae) from South America, activates a novel apoptotic response in a number of cell lines. In the present report, we investigated the effects of ${\beta}-lapachone$ on the growth of human lung in human non-small-cell-lung-cancer A549 cells. Upon treatment with ${\beta}-lapachone$, a concentration-dependent inhibition of cell viability and cell proliferation was observed as measured by hemocytometer counts and MTT assay. The ${\beta}-lapachone-treated$ cells developed many of the hallmark features of apoptosis, including membrane shrinking, condensation of chromatin and DNA fragmentation. These apoptotic effects of ${\beta}-lapachone$ in A549 cells were associated with a marked induction of pro-apoptotic Bax expression, however the levels of anti-apoptotic Bcl-2 expression were decreased in a dose-dependent manner. Accordingly, elevated amount of cyclin-dependent kinase inhibitor p21 expression accompanied by up-regulation of tumor suppressor p53 was observed. By RT-PCR analyses, decrease in gene expression level of telomerase reverse transcriptase and telomeric repeat binding factor were also observed. Thus, these findings suggest that ${\beta}-lapachone$ may be a potential anti-cancer therapeutics for the control of human lung cancer cell model.

• Journal of Korean Society of Forest Science
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• v.103 no.2
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• pp.189-195
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• 2014

Basic leucine zipper (bZIP) protein is a regulatory transcription factor that plays crucial roles in growth, development and stress response of plant. In this study, we isolated a PagbZIP1 gene that belonged to Group SE3 of bZIP from Populus alba ${\times}$ P. glandulosa, and investigated its expressional characteristics. The PagbZIP1 is 844 base pairs long and encodes a putative 144-amino-acid protein with an expected molecular mass of 16.6 kDa. The PagbZIP1 has two conserved domains including the basic and leucine zipper portions. Southern blot analysis revealed that two copies of the gene are presented in the poplar genome. PagbZIP1 was specifically expressed in the root and suspension cells. Moreover, the expression of PagbZIP1 was induced by drought, salt, cold and ABA. Therefore, our results indicated that PagbZIP1 might be expressed in response to abiotic stress through the ABA-mediated signaling pathway in poplar.

• Journal of the Korea Organic Resources Recycling Association
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• v.26 no.4
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• pp.11-19
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• 2018

This study was conducted to develop the manufacturing method of biochar using pruned stems of pear tree and its application effect on the crop growth and soil physico-chemical properties. In this study, biochar derived from pruned stems of pear tree at heating temperature of $300^{\circ}C$, $500^{\circ}C$ and $700^{\circ}C$ in heating times of 2, 3 and 4 hours, were tested in the changes of their chemical properties during biochar processing. The pH, Exch. K, Exch. Mg and cation exchange capacity (CEC) increased as the pyrolysis temperature increased during the production of biochar, and the change of these properties rapidly occurred at $500^{\circ}C$. However, as the pyrolysis temperature increased, ash content increased and total carbon (T-C), yield decreased. And the change of the properties in response to the heating time was not shown. It was thought that it would be desirable to set the production conditions of biochar at $500^{\circ}C$ for 2 hours in consideration of the change of chemical properties and the ash content and yield. And also, were conducted the experiments to establish manufacturing method of farm-made biochar using drum biochar manufacturing machine and investigate the application effects of biochar on the cultivation of chinese cabbage and tomato. Application of biochar derived from pruned stems of pear tree could enhance pH, organic matter (OM), total carbon (T-C) of soil. On the other hand, soil electrical conductivity (EC), NO3-N were lowered compared to the control which has no application. The bulk density, porosity and aggregate formation of soil were improved by biochar application. The fresh matter yields of chinese cabbage and tomato were significantly increased in proportion to the application rate of biochar. This study demonstrated the effect of the biochar derived from agricultural byproduct to be as a low cost potential soil ameliorant by physico-chemical properties in eco-friendly greenhouse cultivation.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.2
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• pp.124-131
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• 2010

This study was conducted to investigate the potentials for the forest restoration on reclaimed land by using willow trees (Salix koreensis Anderson) selected from a coastal reclaimed land made in inside of the Sihwa tide embankment. We first collected six individual willow trees that were the only tree species grown in the reclaimed land. Total 7 clones from cuttings of the collected trees and the control were grown in a greenhouse for two months prior to applying the different concentrations of NaCl solutions (0.0%, 0.1%, 0.5%, and 1.0%). One month after the NaCl application, the survival rates of clones from both the collected trees, and the control were significantly decreased in a NaCl dose-dependent manner. However, there was no significant difference between the collected trees and the control in terms of survival rate, hight and diameter of cuttings, and the numbers of leaves in greenhouse condition. In conclusion, the willow trees collected from the coastal reclaimed land showed no tolerance against NaCl compared to the control grown in ordinary soil, suggesting that further study is required to determine what the most important factor is to select salt tolerant tree species.

• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.1
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• pp.55-60
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• 2007

This study was conducted to find characteristics of photosynthesis for dwarf and street tree cultivars of Hibiscus syriacus L. Characteristics of growth and flowering on some cultivars were investigated. The photosynthetic capacity for the cultivars was also measured. Bulsae showed the best height increase; Soyang represented the lowest growth. Baektanshim ${\times}$ Kyungbuk1 had the largest number of branches and leaves. Sundeok and Bulsae were the best in terms of height and width of flower, Soyang showed the smallest flowers. According to the analysis of chlorophyll content (chlorophyll a, b, total) for the cultivars, there was little difference between Sundeok and Bulsae. Based on light response curves for cultivars, it was found that Baektanshim ${\times}$ Kyungbuk1 and Soyang had lower light compensation and light saturation points than Bulsae and Sundeok. Cultivars Baektanshim ${\times}$ Kyungbuk1 and Soyang were also low in dark respiration, photosynthetic capacity, and net apparent quantum yield. In conclusion, it is recommended that cultivars Baektanshim ${\times}$ Kyungbuk1 and Soyang might be used as a dwarf type due to photosynthetic capacity.

• Korean Journal of Agricultural and Forest Meteorology
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• v.13 no.3
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• pp.115-122
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• 2011

The impacts of elevated temperature and $CO_2$ were studied on the seedlings of Maackia amurensis and Viburnum opulus var. calvescens. The seedlings were grown in controlled-environment growth chambers with four combinations of temperature and $CO_2$ treatments: $25^{\circ}C$ + ambient $CO_2$ (400 ppm), $25^{\circ}C$ + elevated $CO_2$ (800 ppm), $30^{\circ}C$ + ambient $CO_2$ (400 ppm), and $30^{\circ}C$ + elevated $CO_2$ (800 ppm). Under elevated temperature and $CO_2$ concentration, the dry weight decreased in seedlings of M. amurensis, but increased in seedlings of V. opulus var. calvescens. In addition, the shoot to root (S/R) ratio in M. amurensis reduced but that of V. opulus var. calvescens increased under elevated $CO_2$ concentration. The S/R ratios of two tree species increased under higher temperature. M. amurensis represented lower carboxylation efficiency under higher temperature and $CO_2$ concentration and that of V. opulus var. calvescens showed lower values under the only higher temperature. Photosynthetic pigment content of in the leaves of M. amurensis was lower under higher $CO_2$ concentration and higher under the increase of temperature, but that of V. V. opulus var. calvescens decreased according to the increase of temperature. Chlorophyll a/b ratios of M. amurensis and V. V. opulus var. calvescens decreased obviously with the increase of $CO_2$ concentration and temperature, respectively. In conclusion, the growth and physiological responses under the environmental changes such as temperature and $CO_2$ concentration depend on the tree species. Therefore, more studies are needed to predict the response of each tree species against the climate changes.