• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.2
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• pp.45-53
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• 2006

The objectives of this study are to determine the primary yield components responsible for yield differences in a subtropical environment of the Hunan province China and in a temperature environment of Honam province Korea. Field experiments were conducted in a subtropical environment in Hunan province China during 2002 and in a temperate environment in Honam province Korea during 2003. Seven rice cultivars were grown under optimum crop management in each experiment field. Yield, yield components and plant dry matter were determined at maturation. The highest yield (567 kg/10a) was produced at Honam province by Jinyou 207, a Chinese cultivar, The maximum yield at Hunan province was 453 kg/10a by Sanyou 63. On the average across cultivars, Honam produced 23% greater yields than Hunan. Sink size (spikelets per $m^2$) was responsible far these yield differences. Panicle number per $m^2$ was much greater at Honam.

• Horticultural Science & Technology
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• v.31 no.1
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• pp.50-55
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• 2013

The objective of this research was to investigate the impact of Ca fertilizer on the growth of mother plants, physiological disorders, and occurrence of daughter plants in propagation of 'Seolhyang' strawberry through plastic bag cultivation. To achieve this, chemicals of 1.125 mM $Ca(OH)_2$, 0.375 mM $MgCl_2$, 1.250 mM KCl were blended and designated to combined fertilizer (CF). Then, the effect was compared to the treatment of no Ca application (control) and a commercial fertilizer, CalMag (13-0-1.9-16-6:N-$P_2O_5$-$K_2O$-CaO-MgO), when those were applied every two weeks with controlled electrical conductivity (EC) of solution such as 0.6 or 1.0 $dS{\cdot}m^{-1}$. The number of plants showing Ca deficiency symptoms was the highest in control treatment, but those decreased significantly in CF or CalMag treatments. The differences between CF and CalMag in appearance of Ca deficient plants were not significant when two fertilizers were applied with same EC. The fresh and dry weights of mother plants were the greater in the treatments of CF or CalMag than those of control treatment. The treatments of 1.0 $dS{\cdot}m^{-1}$ of CF or CalMag were more effective than those of 0.6 $dS{\cdot}m^{-1}$ on the fresh and dry weight of the mother plants. The runner lengths in the treatment of 1.0 $dS{\cdot}m^{-1}$ of CF were the longest among the all treatments tested. The treatments of 1.0 $dS{\cdot}m^{-1}$ were more effective than those of 0.6 $dS{\cdot}m^{-1}$ of CF or CalMag in lengths and fresh and dry weight of runners. The fresh and dry weights of daughter plants were heavier in the treatments of CF than those of CalMag. Based on the above results, we concluded that the Ca deficiency in raising 'Seolhyang' strawberry can be lessened by the application of Ca containing fertilizers, but combined application of Ca, K and Mg was more effective than that of Ca alone for seedling production.

• Horticultural Science & Technology
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• v.29 no.1
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• pp.1-9
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• 2011

This study was performed to investigate the role of plant growth substances on the bulbing of cold type of garlic (Allium sativum L. cv. Uiseongmaneul) during long and short day conditions. The change in endogenous plant hormones such as abscisic acid (ABA), jasmonic acid (JA) and sugar contents in leaf blade and sheath was examined during the growth stage from bulb differentiation (starting at April 16) to bulbing (April 24 to May 18) in cold type of garlic. In the long day condition, ABA contents were higher than short day condition and ABA contents of leaf sheath were higher than leaf blade. ABA contents of growth stage in garlic were not changed during growth stage from April 16 to May 2, however it rapidly increased during bulbing (May 2 to May 18). On the other hand, endogenous JA contents in short day condition did not change in long day condition, it increased from April 16 to May 2. JA contents in the leaf sheath (33.85-62.04 $ng{\cdot}g^{-1}$ DW) were higher than leaf blade (15.39-30.04 $ng{\cdot}g^{-1}$ DW). These results showed that garlic bulb differentiation and bulbing was induced by JA in leaf sheath. In long day condition, total sugar contents in the leaf blade were increased from bulb differentiation (April 16) to bulbing (May 4) and it was decreased during bulbing (May 4 to May 18) while the total sugar content in leaf sheath were gradually increased from bulb differentiation (April 16) to bulbing (May 18). In conclusion, our results showed that there is a significant correlation between the bulb development of garlic and hormonal content in the leaf sheath.

• FLOWER RESEARCH JOURNAL
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• v.19 no.1
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• pp.22-29
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• 2011

The experiment investigated effect of duration, temperature, and light condition during chilling treatment on growth and flowering of four Campanula species in a factorial experiment. Two parent species, Campanula punctata Lam. var. rubriflora Mak. and C. Punctata Lam., and their two $F_1$ hybrids, C. punctata Lam. ${\times}$ C. punctata Lam. var. rubriflora Mak. ('Jiknyeo') and C. punctata Lam. var. rubriflora Mak. ${\times}$ C. punctata Lam. ('Gyeonu'), were used. Plants were cultured in vitro for five weeks at $25^{\circ}C$ under about $75{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD before being chilled at 4 or $25^{\circ}C$ for 3, 6, or 9 weeks under a darkened or lighted (about $10{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD) condition. After chilling treatment, plants were transplanted to 10 cm pots filled with a commercial growing medium and were transferred to environment-controlled growth chambers and subsequently to a greenhouse to observe their reproductive growth. Growth of all species and flowering of a $F_1$ hybrid 'Jiknyeo' were affected by duration, temperature, and light condition during chilling treatment. The greatest growth and survival percentage were observed in C. punctata Lam. var. rubriflora Mak. The survival percentage was greater when plants were chilled in a lighted than darkened condition, whereas it decreased when plants were chilled more than six weeks in vitro. Among the four species tested, flowering was observed only in a $F_1$ hybrid 'Jiknyeo' with 62.5% flowering plants when it was chilled at $25^{\circ}C$ for three weeks under a lighted condition. Percent flowering plant was affected by duration, temperature, and light condition during chilling treatment. Three-week chilling at $4^{\circ}C$ under a darkened condition significantly reduced days to flowering. These results suggest that the low temperature requirement for flowering is not qualitative but quantitative in Campanula species. Further experiment with more number of plants is necessary to ascertain this conclusion.

• FLOWER RESEARCH JOURNAL
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• v.19 no.2
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• pp.89-95
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• 2011

This study was conducted to improve commercial quality of cut spray chrysanthemums 'Charming Eye' and 'Pink Pride' bred in Korea by foliar application of daminozide, suppressing excessive elongation of peduncle caused by high temperature in greenhouse. Applications were made at two floral-bud-developmental stages and concentrations used were 0, 500, 1000, and $2000mg{\cdot}L^{-1}$. As for 'Charming Eye', cut flower length, peduncle diameter, stem diameter, flower bud diameter, and the number of flower buds did not show any significant difference among all treatments including control. However, the suppressing effect of peduncle elongation, widening angle of flower cluster arrangement on apical part, and increasing parallel flower buds in stage I showed better than those in stage II regardless of daminozide concentration. As for 'Pink Pride', cut flower length, peduncle diameter, and stem diameter did not show any significant difference among all treatments including control but angle of flower cluster on apical part increased compared to control as daminozide was sprayed at stage I and II except $2,000mg{\cdot}L^{-1}$ daminozide-sprayed at stage II. The number of flower buds and flower bud diameter showed the greatest increment through $1,000mg{\cdot}L^{-1}$ daminozide-sprayed at stage I and did the least values as sprayed with $2,000mg{\cdot}L^{-1}$ daminozide at stage II. Daminozide also gradually reduced peduncle length in a concentration-dependant manner but elongation of peduncle foliar-sprayed at stage I showed the more suppressing effect than that at stage II. Increasing the number of parallel flower buds showed the best results when sprayed with $2,000mg{\cdot}L^{-1}$ at stage I. In conclusion, we recommended that foliar spraying with $500-1,000mg{\cdot}L^{-1}$ daminozide at stage I and foliar spraying with $1,000-2,000mg{\cdot}L^{-1}$ daminozide at stage I improved cut flower quality of 'Channing Eye' and 'Pink Pride', respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.4 no.1
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• pp.13-19
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• 1971

In order to establish the method of improving ill drained paddy soil where the accumulation of absorption inhibitor is worried in the earlier stages of rice growth, proper soil is selected and an field experiment is designed having treatments such as lime materials, none sulfate fertilizers, boron and straw etc. The data of yield and plant analysis in different stages of rice growth is eveluated and discussed to obtain following summaries. (1) Significant yield increase was made by the treatment of lime materials such as slacked lime or wollastonite powder, materials inhibiting the activity of microorganisms such as boron and of none sulfate fertilizers lacking inhibitor producing sources. (2) The crop scientifice causes of decreasing yield are the decreasing the number of panicles per hill, grains per panicle and the weight of grains. (3) The plant nutritional causes of decreasing yield are the lowering of nitrogen content throughout the life, phosphate content since young premodia formation stage of plant and the decreased content of magnesium, calcium and silicate in straw at harvesting stage. (4) The causes of lowering the content of various elements in rice plant grown in ill drained paddy soil are suggested as root damage by producing and accumulating absorption inhibitors such as organic acids and hydrogen sulfide etc, from the following observed facts; (a) In young premodia formation stage, attaining to the maximum production and accumulation of absorption inhibitor, the phosphate accumulation in plant was smaller in the phosphate plots than without phosphate plots and much higher in the neutralized plots by adding lime materials. (b) In the plots of straw addition, the potassium content in plant at the young premodia formation stage is very low probabley due to root damage by absorption inhibitor produced from the process of straw decomposition but higher at the stage of harvesting probably due to the immetabolic negative absorption of damaged roots. (c) The effect of boron, known as the inhibitor of microorganism activity to decompose organic matter, is apparent. (d) The effect of nonsulfate fertilizer treatment, having no source of producing inhibitor such as hydrogen sulfide, was significant. (e) All the yield components, decided around the young premodia formation stage attaining to the maximum inhibitor concentration in soil and minimum root activity, are significantly decreased.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.2
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• pp.101-107
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• 2005

To investigate the effect of pyroligneous acid liquor (PAL) on the maturity of pig manure compost, PAL was treated to the compost piles. The treatments included applications of 100 and 300 times diluted PAL in addition to the control. The compost piles were stirred in three times at the 1st, 10th, and 25th day of composting. Temperature in the compost pile of control treatment increased from 28 to $60^{\circ}C$ within 10 days and remained nearly at the level until 30th day, then it began to decrease. On the other hand, temperature of the PAL-100 and PAL-300 treatments reached 65 to $70^{\circ}C$ within 8 days and became stabilized until 30th day, then the temperature decreased to about $28^{\circ}C$. However, the temperature of control was stabilized approximately at the 40th day. Initially, the pH of control treatment dropped from 8.2 to slightly above pH 8.0 during 4th day, but that of the PAL-100 treatment declined to 7.8. Among treatments, pH value of PAL-100 treatment was the lowest, which was about 7.3 after becoming stabilization. Also the germination index (GI) was increased at all treatments. The C/N ratio range of PAL-100 treatment was better balanced than others and was at 24.3. Moreover the round paper chromatogram of extracted solution of compost of PAL-100 treatment was the sharpest and clearest among treatments. The GI values of control, PAL-100, and PAL-300 in 60 days of composting were about 108, 120, and 118 in germination test using chinese cabbage, respectively. It can be concluded that the addition of diluted PAL solution is effective in composting of pig manure.

• Journal of Bio-Environment Control
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• v.28 no.2
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• pp.178-184
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• 2019

Strawberry ($Fragaria{\times}ananassa$) is one of the most important and popular fruit crops in the world, and 'Sulhyang' is one of the principal cultivars cultivated in the Republic of Korea for the domestic market. The growth and flower induction in strawberry is the process which influences directly on fruit bearing and yield of this crop. In this study, effect of benzyladenine (BA), gibberellic acid ($GA_3$), and salicylic acid (SA) on growth and flower bud induction in strawberry 'Sulhyang' was investigated. The 3-week-old runner plants, grown in 21-cell propagation trays, were potted and cultivated in growth chambers with $25^{\circ}C/15^{\circ}C$ (day/night) temperatures, 70% relative humidity (RH), and light intensity of $300{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ photosynthetic photon flux density (PPFD) provided by white light emitting diodes (LEDs). The runner plants were treated with one of three concentrations, 0 (control), 100, and $200mg{\cdot}L^{-1}$ of BA, $GA_3$, or SA solution. The chemicals were sprayed two times on leaves of runner plants at an interval of two weeks. After 9 weeks the results showed that the application of all chemicals caused reduction of root length and chlorophyll (SPAD) content as compared to the control. The lowest chlorophyll (SPAD) content was recorded in plants treated with $GA_3$. However, the treatment of $200mg{\cdot}L^{-1}$ $GA_3$ promoted leaf area, leaf fresh weight, and plant fresh weight. The greatest flower induction (85%) and number of inflorescences (4.3 inflorescences per plant) were observed in the treatment of $200mg{\cdot}L^{-1}\;SA$, followed by $100mg{\cdot}L^{-1}\;SA$. Overall, results suggest that foliar application of $GA_3$ solution could accelerate plant growth, while foliar application of SA solution could induce hastened flowering. Further studies may be needed to find out the relationship between $GA_3$ and SA solutions treated in a combination, and the molecular mechanism involved in those responses observed.

• Journal of Wetlands Research
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• v.20 no.4
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• pp.295-303
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• 2018

Inland wetlands in the Republic of Korea provide key breeding and wintering habitats, while coastal wetlands provide nutrient-rich habitats for stopover sites for East Asia/Australasia Flyway(EAAF) migrants. However, since the 1960's, Korea has reclaimed these coastal wetlands gradually for agriculture and urban expansion. The habitat loss has rippled across global populations of migrant shorebirds in EAAF. To protect a similar loss, the United States, specifically Missouri, developed the moist-soil management technique. Wetland impoundments are constructed from levees with water-flow control gates with specific soils, topography, available water sources, and target goals. The impoundments are subjected to a combination of carefully timed and regulated flooding and drawdown regimes with occasional soil disturbance. This serves a dual purpose of removing undesirable vegetation, while maximizing habitat and forage for wildlife. Flooding and drawdown schedules must be dynamic with constantly shifting climate conditions. Korea's latitude ($N33^{\circ}25^{\prime}{\sim}N38^{\circ}37^{\prime}$) is comparable to Missouri ($N36^{\circ}69^{\prime}{\sim}N40^{\circ}41^{\prime}$); as such, moist-soil management could prove to be an effective wetland restoration technique for Korea. In order to meet specific conservation goals (i.e. shorebird staging site restoration), it is necessary to test the proposed methodology on a site that can meet the required specifications for moist-soil management. Moist-soil management has the potential to not only create key habitat for endangered wildlife, but also provide valuable ecosystem services, including water filtration.

• Korean Journal of Heritage: History & Science
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• v.51 no.1
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• pp.32-47
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• 2018

The purpose of this study is to examine the vegetation maintenance project that was conducted as a part of the Official Development Assistance (ODA) project for the historic site of Angkor, to analyze the aspects and characteristics of the project, and to derive implications for the establishment of future policies and strategies. First, the key words used in the vegetation maintenance project at the historic site of Angkor do not only refer to the concept of plants (and more specifically to 'trees') but also to the concept of heritage. In other words, the concept of heritage is not limited to architectural structures but is also intended to mean the vegetation and surroundings that form the historic site. Second, the expansion of the value of vegetation has contributed to the establishment of the basic principles of conservation based on the 'coexistence' between architectural structures and vegetation; here, vegetation has come to be recognized as an 'essential' element in the conservation of historic sites. Third, the range of vegetation maintenance has expanded from each tree to the surroundings of the temples, and vegetation maintenance came to adopt 'integrative' and 'active' directions to improve not only the growth environment of the vegetation but also the viewing environment experienced by visitors. This change means that it is necessary for the historic site maintenance project to comprehensively deal with the temples and their surrounding areas. Fourth, for the effective performance of the ODA project, the role of the International Coordinating Committee for the Safeguarding and Development of the Historic Site of Angkor (ICC-Angkor), under the influence of UNESCO, was expanded from an examination of the problems with the existing projects to a search for solutions to technical consultation and supervision. This implies that, in order to perform the ODA project in a way that is appropriate to the local conditions, it is important to reach gradual and phased agreements with ICC-Angkor.