• Horticultural Science & Technology
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• v.29 no.3
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• pp.217-223
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• 2011

This study was conducted to examine the effect of several pretreatments and holding solutions on the vase life and quality of cut Polygonatum odoratum var. pluriflorum for. variegatum stems native to Korea. Postharvest foliar spray of 200 $mg{\cdot}L^{-1}$ $GA_3$ or 200 $mg{\cdot}L^{-1}$ BA + 200 $mg{\cdot}L^{-1}$ $GA_3$ markedly extended the vase life of cut stems of Polygonatum odoratum var. pluriflorum for. variegatum. These treatments maintained high chlorophyll contents as compared with the control (distilled water) during senescence of cut stems. Postharvest pretreatment (dipping) with 100 $mg{\cdot}L^{-1}$ $GA_3$ or 3% sucrose + 200 $mg{\cdot}L^{-1}$ 8-hydroxyquinoline sulfate (HQS) + 100 $mg{\cdot}L^{-1}$ $GA_3$ for 16 hours extended vase life of cut stems 2.5 times as long as nontreated control. Holding solution of 2% sucrose + 200 $mg{\cdot}L^{-1}$ HQS + 100 $mg{\cdot}L^{-1}$ $GA_3$ significantly extended vase life by 3.5 times and increased fresh weight as compared with control. $GA_3$ were very effective on preventing leaf yellowing of cut Polygonatum odoratum var. pluriflorum for. variegatum stems. Postharvest foliar spray of 200 $mg{\cdot}L^{-1}$ $GA_3$ or holding solution of 2% sucrose + 200 $mg{\cdot}L^{-1}$ HQS + 100 $mg{\cdot}L^{-1}$ $GA_3$ markedly extended vase life and improved quality of cut stems of Polygonatum odoratum var. pluriflorum for. variegatum.

• Journal of the Korean Society for Marine Environment & Energy
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• v.10 no.3
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• pp.127-137
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• 2007

To confirm whether or not the Electrochemical Disinfection System (EDS) meet with the D-2 regulation established by IMO (International Maritime Organization), the biological treatment efficacy of the EDS was assessed using three groups of natural marine plankton (bacteria, $10-50\;{\mu}m$ and $>50\;{\mu}m$ sized organisms). Influent water was passed through the EDS under the flow velocity ($23.8\;m^3/hr$) and test design was consisted of control (no treatment) and experimental (10 ppm and 30 ppm) condition for total residual chlorine (TRC). And the biological condition of the influent water followed the standards established by the guidelines for the approval of ballast water management systems. The disinfection efficacy of the $10-50\;{\mu}m$ sized organisms (phytoplankton) was assessed by three kinds of measurements using photomicroscope, epifluorescence microscope and fluorometer (fumer Designs 10-AU). After being passed through the EDS, all motile phytoplankton lost their motility under photomicroscope, the colour of chlorophyll fluorescence fumed from red into green under epifluorescence, and the high chlorophyll fluorescence (Expt. 1: 6.95, Expt. 2: 7.11) detected by fluorometer decreased into value not detected. These results indicated phytoplankton community was totally killed after electrochemical disinfection treatment. Survivorship of the larger organisms than $50\;{\mu}m$ was determined based on the appendage's movement under a stereomicroscope. Natural assemblage collected from ambient seawater was killed shortly after being passed through the EDS, whereas some Artemia remained alive. However, no live Artemia was found after 24 hour further exposure to each TRC concentration (10 and 30 ppm) under darkness. After electrochemical treatment, the target bacteria such as aerobes, coliform and Escherichia coli were completely killed on the basis of CFU (colony forming unit) on Petrifilm plate ($3\;M^{TM}$) after 48 hr incubation. Moreover, no regrowth was found in the three groups of plankton during five days under additional exposure to the treated water. These results indicated that the disinfection efficiency of the EDS on the three groups of plankton satisfy D-2 regulation.

• The Korean Journal of Malacology
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• v.29 no.1
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• pp.51-63
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• 2013

To assess the effect of environmental factors on the sustainability of cultured production shellfish, we investigated the habitat characteristics of tidal flat (Namhae-po in Taean). We measured the physiochemical parameters (temperature, salanity, pH, dissolved oxygen and nutrients) and the geochemical characteristics (chemical oxygen demand, ignition loss, C/N ratio and C/S ratio). Surface sediments were collected from several site of tidal flat to examine the geochemical characteristics of both the benthic environment and heavy metal pollution. The grain size for research area of tidal flat were similar at the ratio of silt and clay in comparison with the other site of it. The C/N ratio was more than 5.0, reflecting the range arising from the mix of marine organism and organic matter. The C/S ratio (about 2.8) showed that survey area had anoxic or sub-anoxic bottom conditions. The enrichment factor (Ef) and index of accumulation rate (Igeo) of the metals showed that those research areas can be classified as heavily polluted, heavily to moderately polluted, or more or less unpolluted, respectively. Adult surf clam (Mactra veneriformis) density was highest at St. 2 (middle part of the Namhae-po), on the other hand, surf clam spat density was highest at St. 3 (lower part of the Namhae-po). Heavy rain, terrigenous suspended clay with fresh water from neighboring agricultural land, and severe high air temperature during summer could be thought as detrimental causes of spat and adult mortality in Namhae-po tidal flat. We suggested that the growth of shellfish in the tidal flat was effected by the various environmental conditions, so an improvement in the cultured method was needed.

• Korean Journal of Plant Resources
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• v.19 no.1
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• pp.1-7
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• 2006

This study was conducted to determine chemical compounds and antioxidant in Aruncus dioicus. Further, effects of cultural practices such as the shading conditions on the general compounds, essential oils and antioxidants. The chemical compounds and antioxidant activity of edible extracts on the shading cultivation and harvesting time were measured by crude fiber, pigments, higher fatty acids, essential oils and DPPH free radical scavenging ability and activities of SOD and POD in edible shooting parts of Aruncus dioicus. The contents of crude fiber, total chlorophyll and total carotenoids in extracts of edible shooting by shading cultivation and later harvesting were higher than those of non-shading cultivation and early harvesting. Phenolic compounds such as benzoic acid were identified as the aromatic compounds in the edible extracts of Aruncus dioicus. The contents of azulene, benzaldehyde and linalool among those compounds on the cultivation conditions increased in shading cultivation. $IC_{50}$ values of DPPH free radical scavenging activities were high from 6.644 to $14.499{mu}g/m{\ell}$ in extracts of edible parts and those of edible shooting parts was high such as edible shooting cultivated by 60% shading, 30% shading and non-shading, respectively. The activity of POD and SOD in seeds was lower than that of edible shooting and that by shading cultivation was high in extracts cultivated by non-shading. POD activity of extracts on harvesting time was high in earlier harvesting but SOD activity was low. The numbers of isozyme pattern of POD and SOD in seedling showed 7 bands and 3 bands, respectively, especially, bands of POD and SOD in the first year-growing plant did not show and show a difference according to plant positions, respectively.

• The Korean Journal of Pesticide Science
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• v.9 no.1
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• pp.70-80
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• 2005

To evaluate the exposure of molinate in agricultural environment and its effect against the non-target crop in air, this experiment was conducted to elucidate volatilization characteristics of molinate in aquatic condition and to determine critical concentration of molinate in the air causing phytotoxicity to Chili pepper. Cumulative volatilized rate of molinate from water was 22.7% at $35^{\circ}C$ for water temperature and 20 L/min for air velocity while 3.2% at $25^{\circ}C$ and 10 L/min within 47 hour after applied under closed system, respectively. The molinate concentrations in air above 60 cm height from soil surface of valley and open paddy rice field were reached the highest value of 18.17 and $11.59{\mu}g/m^3$, respectively within 24 hours after applying granular formulation at dose rate of molinate 150 g/1,000 $m^2$. However, their concentrations were drastically diminished to around 0.18 and $0.51{\mu}g/m^3$ level in 20 days after application, which volatilization pattern were similar to both regions. Also, the concentration of molinate in air above 60 cm height from soil surface was distributed higher 2 times than that above 180 cm height. Meanwhile, a phytotoxic symptom against the nearby chili pepper was revealed within three days after applied and molinate was detected $0.004{\sim}0.006$ mg/kg level from severe damaged leaves. The dose and exposure relations of molinate in the air against the non-target crop was also investigated in lab trial. The phytotoxic symptom, shriveled leaves, of the chili pepper was encountered by exposing two days with concentration of $13.6{\mu}g/m^3$, three days with $6.8{\mu}g/m^3$ or four days with $3.4{\mu}g/m^3$. The symptom was still recovered within four weeks after the plants had received fresh air. On the other hand, the phytotoxic response through root uptake of the herbicide in water culture was relatively insensitive, in which the symptom is observed ten days with the concentration of 300 ${\mu}g/L$.

• Korean Journal of Agricultural Science
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• v.19 no.1
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• pp.16-27
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• 1992

To determine a potential of new sludge fertilizer for horticultural crops, comparative studies between commercial fertilizers (Jandibiryo and Wonyebokbi) and sludge fertilizer (Sludgebiryo) were made through examining the growth responses on zoysiagrass (Zoysia japponica Steud.) and several horticultural plants. 1. The pH of new sludge fertilizer remained near 6.5 regardless the particle size. The solubility of elements was highest in phosphorus, followed by nitrogen and potassium in the order. Especially, desorption of potassium was continued up to 48 hrs after solubilization. 2. There was an increase in shoot number per plant, length of stolon and rhizome, and root weight as well as clipping yield of zoysiagrass in the treatment of large size Sludgebiryo compared to small one and Jandibiryo. 3. Regardless the size of fertilizers, Sludgebiryo increased flower numbers in salvia (Salvia officinalis L. 'Hatzazz') compared to Wonyebokbi, although the difference was not great, However, leaf area and fresh weight of plant were more increased in Wonyebokbi application. 4. Flower diameter of marigold (Tagetes erecta L. 'Inca') was slightly increased in Sludgebiryo application, but the average number of lateral shoots and fresh weight per plant were significantly increased in the treatment of Wonyebokbi application. 5. Sludgebiryo effectively increased the length of both main and lateral shoots, number of flowers and weight of shoot in vinca (Vinca rosea L. 'Little Linde'), but root growth of plant was higher in Wonyebokbi application. 6, No differences between Wonyebokbi and Sludgebiryo were found in promoting the growth of leaves of perilla (Perilla frutescens Hara 'Yubsil' ), but chlorophyll content and seed weight were slightly higher in the application of Wonyebokbi compared to Sludgebiryo. In conclusion, the effectiveness of Sludgebiryo for horticultural plants was almost equal to commercial fertilizers such as Jandibiryo or Wonyebokbi. Expecially, Sludgebiryo appeared to effective on the growth of zoysiagrass, and the increase of flower size and numbers in flower crops. Results indicate that new-made Sludgebiryo can be recommended for turfgrass culture, and the flower crops in which quality depends on flower number and flower size.

• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.305-311
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• 2012

To investigate the influence electrical conductivity (EC) of nutrient solution and light intensity on growth of red leafy lettuce, fresh and dry weights, number of leave, chlorophyll concentration and production efficiency were evaluated through nutrient film technique system. The levels of EC were 0.5, 1.0, 1.5, 2.0, 3.0, and $6.0dS{\cdot}m^{-1}$, and those of light intensity were 120, 150, and $180{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Under photoperiod of 16 h/day, the temperature was maintained in the range of $20{\sim}25^{\circ}C$. Planting density was $10{\times}10cm$ (100 plants/$m^2$). When red leafy lettuce were grown in the EC range of $0.5{\sim}1.5dS{\cdot}m^{-1}$, the fresh and dry weights decreased as the EC levels and light intensity were lowered, however, Hunter's a value showed no significant differences among the treatments of EC and light intensity levels (Ex. 1). The fresh and dry weights and production efficiency ($g{\cdot}FW/kw$) were the highest in the treatment of $3.0dS{\cdot}m^{-1}$ and $180{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ when crops were grown under the EC range of EC $1.5{\sim}6.0dS{\cdot}m^{-1}$ (Ex. 2). But the fresh and dry weights, number of leaves, and production efficiency of $2.0dS{\cdot}m^{-1}$ were the highest when the light intensity was $180{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ (Ex. 3). The SPAD value increased gradually as EC levels were elevated. From the above results, we concluded that optimum levels of EC and light intensity were $2.0dS{\cdot}m^{-1}$ and $180{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, respectively, for production as well as production efficiency of red leaf lettuce in plant factory.

• Journal of Plant Biotechnology
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• v.40 no.2
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• pp.79-87
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• 2013

The aim of this study was to establish plant regeneration from leaf explants of Sedum tosaense Makino, which is globally rare and endangered species. The leaf explants of S. tosaense were cultured on the MS medium supplemented with different concentration of BA and NAA for callus induction. Callus induction was showed the highest (100%) on MS medium containing $2.0mg{\cdot}L^{-1}$ BA and $1.0mg{\cdot}L^{-1}$ NAA. The highest number of shoots were regenerated when callus were cultured on MS medium containing $2.0mg{\cdot}L^{-1}$ BA and $1.0mg{\cdot}L^{-1}$ NAA for 5 weeks. The axillary bud were cultured on the MS media supplemented with combination of BA and NAA for in vitro propagation. The highest number of adventitious shoot (7.9 per explants) formed at $1.0mg{\cdot}L^{-1}$ NAA and $2.0mg{\cdot}L^{-1}$ BA. For rooting, MS medium supplemented with or without $2.0g{\cdot}L^{-1}$ activated charcoal was tested. The optimal results were observed using MS medium supplemented with $2.0g{\cdot}L^{-1}$ activated charcoal, on which 85.7 (No. of root), 4.6 cm (length of root). 1,200 ppm $CO_2$ and 350 ppm $CO_2$ were supplied for make certain the effects of $CO_2$ on pre-acclimatization by photoautotrophic culture. 1,200 ppm $CO_2$ treatment was established higher than 350 ppm $CO_2$ treatment. Soil acclimatization of in vitro plantlets was the best in mixture soil consisted of peat moss and perlite with 100% survival rate and they showed the maximum growth.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.779-787
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• 2011

This study was conducted to evaluate the usefulness of ground-based remote sensing for the estimation of rice yield and application rate of N-fertilizer during growing season. Dongjin-1, Korean cultivar of rice was planted on May 30, 2006 and harvested on October 9, 2006. Chlorophyll content and LAI (leaf area index) were measured using Minolta SPAD-502 and AccuPAR model LP-80, respectively. Reflectance indices were determined with passive sensors using sunlight and four types of active sensors using modulated light, respectively. Reflectance indices and growth rate were measured three times from 29 days to 87 days after rice plating and at harvesting day. The result showed that values of growing characteristics and reflectance indices were highly correlated. Growing characteristics to show significant correlation with reflectance indices were in order of followings: fresh weight > N uptake > dry weight > height > No. of tiller > N content. Chlorophyll contents measured by chlorophyll meter (SPAD 502) showed high correlation with nitrogen concentration (r=$0.743^{**}$), although the correlation coefficients between remote sensing data and nitrogen concentration were higher. LAI was highly correlated with dry weight (r=$0.931^{**}$), but relationship between LAI and nitrogen concentration (r=$0.505^*$) was relatively low. The data of CC-passive sensor were negatively correlated with those of the near-infrared. NDVI correlation coefficients found more useful to identify the growth characteristics rather than data from single wavelength. Both passive sensor and active sensor were highly significantly correlated with growth characteristics. Consequently, quantifying the growth characteristics using reflectance indices of ground-based remote sensing could be a useful tool to determine the application rate of N fertilizer non-destructively and in real-time.

• Korean Journal of Remote Sensing
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• v.37 no.5_2
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• pp.1245-1257
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• 2021

GOCI-II, succeeding the mission of GOCI, was launched in February 2020 and has been in regular operation since October 2020. Korea Institute of Ocean Science and Technology (KIOST) processes and produces in real time Level-1B and 26 Level-2 outputs, which then are provided by Korea Hydrographic and Oceanographic Agency (KHOA). We introduced current status of regular GOCI-II operation and showed future improvement. Basic GOCI-II products including chlorophyll-a, total suspended materials, and colored dissolved organic matter concentration, are induced by OC4 and YOC algorithms, which were described in detail. For the full disk (FD), imaging schedule was established considering solar zenith angle and sun glint during the in-orbital test, but improved by further considering satellite zenith angle. The number of slots satisfying the condition 'Best Ocean' significantly increased from 15 to 78. GOCI-II calibration requirements were presented based on that by European Space Agency (ESA) and candidate fixed locations for calibrating local observation area were. The quality management of FD uses research ships and overseas bases of KIOST, but it is necessary to establish an international calibration/validation network. These results are expected to enhance the understanding of users for output processing and help establish detailed plans for future quality management tasks.