• Journal of Soil and Groundwater Environment
• /
• v.6 no.4
• /
• pp.51-59
• /
• 2001

Column and box tests were performed to investigate the removal efficiency of NAPL using the surfactant enhanced flushing In heterogeneous medium. Homogeneous Ottawa sand and heterogeneous soil were used to verify the increase of remediation efficiency for the surfactant enhanced flushing in column test. Box tests with two different heterogeneous sub-structure were performed to quantify the capability of the surfactant enhanced flushing as a remediation method to remove NAPL from the heterogeneous medium. Two different grain size sand layers were repeated in the box to simulate the heterogeneous layer formation and the modified fault structure was built to simulate the fault system in the box. O-xylene as a LNAPL and PCE as a DNAPL were used and oleamide as a non-ionic surfactant. The maximum NAPL effluent concentration with 1% oleamide flushing in the homogeneous column test increased about 460 times compared to that with only water flushing and about 250 times increased in the real soil column test. In heterogeneous medium, the maximum effluent concentration increased about 150 times in 1% oleamide flushing and most of NAPL were removed from the box within 8 pore volume flushing, suggesting that the removal efficiency increased very much compared to in only water flushing. Results investigated the capability of the surfactant enhanced remediation method to remove NAPL even in heterogeneous medium.

• Korean Journal of Weed Science
• /
• v.31 no.2
• /
• pp.134-145
• /
• 2011

The objectives of this study were to investigate fitness difference in growth and rice yield in herbicide-transgenic rice overexpressing Myxococcus xanthus and Arabidopsis thaliana protoporphyrinogen oxidase (Protox) genes and non-transgenic rice. We also aimed to determine whether these fitness differences are related to ALA synthesizing capacity, accumulation of terapyrroles, reactive oxygen species, lipid peroxidation, and antioxidative enzymes at different growth stages of rice. Plant height of the transgenic rice overexpressing M. xanthus (MX) and A. thaliana (AP37) Protox genes at 43, 50, and 65 days after transplanting (DAT) was significantly lower than that of WT. Number of tiller of PX as well as MX and AP37 at 50 and 65 DAT was significantly lower than that of WT. At harvest time, culm length and yield of MX, PX and AP37 and rice straw weight of MX and AP37 were significantly low compared with WT. The reduction of yield in MX, PX, and AP37 was caused by spikelets per panicle and 1000 grain weight, ripened grain, spikelets per panicle, 1000 grain weight, and ripened grain, respectively. On the other hand, 135 the reduction of yield in MX, PX, and AP37 was also observed in another yearly variation experiment. The reduction of rice growth in MX, PX, and AP37 was observed in seedling stage as well as growth duration in field. There were no differences in tetrapyrrole intermediate Proto IX, Mg-Proto IX and Mg-Proto IX monomethyl ester, reactive oxygen species ($H_2O_2$ and ${O_2}^-$), MDA, antioxidative enzymes (SOD, CAT, POX, APX, and GR) and chlorophyll between transgenic lines and wild type, indicating that accumulated tetrapyrrole intermediate and other parameters were not related to growth reduction in transgenic rice. However, ALA synthesizing capacity in MX, PX, and AP37 at one day after exposure to light and 52 DAT was significantly lower than that of WT. Further study is required to elucidate the mechanisms underlying the growth and yield difference between transgenic and WT lines.

• Korean Journal of Microbiology
• /
• v.49 no.1
• /
• pp.30-37
• /
• 2013

This study was carried out to assess the spatial and tidal effects on the water quality in the lower reaches of Taewha River, Ulsan, Korea and to understand the environmental factors affecting winter algal bloom in the river. From May, 2010 to January, 2011, water samples were collected at five locations (New Samho Bridge, Old Samho Bridge, Mungjung Stream, Taewha Bridge, and Mungchon Bridge) along the river at high and low tides of spring tide. We measured environmental parameters including salinity, dissolved oxygen (DO), biological oxygen demand (BOD), chemical oxygen demand (COD), chlorophyll a (Chl a) and various nutrient concentrations. Salinity increased towards the downstream direction. Average values of Chl a concentrations ranged $10-26mg/m^3$ at high tide and $11-53mg/m^3$ at low tide depending on sampling locations. It was noteworthy that there were strong increases in Chl a concentrations during the November 21 to December 22 sampling period especially at the Taewha Bridge. At the location, Chl a concentrations were measured as $138-296mg/m^3$ for the period; Rhodomonas lacustris of class Cryptophyceae was the dominant algal species. Chl a concentrations at the Taewha Bridge were positively correlated with such parameters as salinity, BOD, DO, COD, pH, and T-N, and negatively correlated with temperature and $NO_3{^-}$-N. On the other hand, at the Mungchon Bridge the highest concentration of Chl a was $55mg/m^3$ on August 25, and Chl a concentrations were positively correlated with $NH_3$-N, T-N, $PO_4{^{3-}}$-P, T-P, and heterotrophic plate counts. The results suggested that water quality in the lower Taewha River fluctuated a lot with the sampling locations and the patterns of algal blooms were different between Taewha Bridge and Mungchon Bridge sampling locations.

• Korean Journal of Medicinal Crop Science
• /
• v.15 no.3
• /
• pp.194-198
• /
• 2007

Yield and ginsenoside contents of ginseng (Panax ginseng C. A. Meyer) is affected by light intensity and quality, and the color and the thickness of PE shading net when PE net is utilized for shading material. This study was carried out to investigate the effect of light quality on root yield and ginsenoside contents off-year-old ginseng by using polyethylene shading net with each blue and yellow color, Spectral irradiance under blue and yellow shading net showed the peak at 498 nm and 606 nm, respectively, which made distinct difference in light quality. Heat injury ratio of blue shading net was increased distinctly more than that of yellow shading net in summer season because of higher transmitted quantum (23%)and air temperature (0.3 $^{\circ}$C) in blue shading net than those of yellow shading net. Chlorophyll content and leaf area under yellow shading net were higher than those of blue shading net, and its heat injury ratio was lower than those of blue. These effects may led to 48% higher increase of root yield under yellow shading net than that under blue shading net. The content of total ginsenoside in taproot was not significantly differed between blue and yellow shading net, while the content in lateral and fine root was significantly increased in blue shading net compared to yellow shading net. PDM ratio of blue shading net showed more significant increase in lateral root than that of yellow shading net. All of Rb$_1$/Rg$_1$ ratio in three parts of root under blue shading net was higher than that of yellow shading net, but there were no significant increase in the ratio of lateral root.

• Journal of Bio-Environment Control
• /
• v.13 no.4
• /
• pp.226-232
• /
• 2004

This experiment was conducted to investigate the effect of night and daytime temperatures on growth and yield of paprika 'Fiesta' and 'Jubilee' under soil culture experiment in the vinyl houses during the 2003 and 2004 season. Total fruit yield was greater in 'Fiesta' than 'Jubilee' Marketable yield was not different between two cultivars, due to lower $\%$ marketable fruits in 'Fiesta'. mean Fruit weight was not different between two cultivars. Difference of yield between cultivars was due to fruit number, harves time and root condition. It was caused by cracked fruits to decrease $\%$ marketable fruits. Total yield was greater in nighttime temperature of $18^{\circ}C\;than\;15^{\circ}C$ and marketable yield was considerably greater because of $\%$ marketable fruits was higher. Mean fruit weight was slightly greater in nighttime temperature of $15^{\circ}C\;than\;18^{\circ}C$. Difference of fruit yield in treatments of nighttime temperature was due to fruit number and harvest time. There was not significant difference of yield between daytime temperature of $28^{\circ}C\;and\;31^{\circ}C$, but in $34^{\circ}C$, total and marketable yields were the least and mean fruit weight was the smallest because of decreased $CO_2$ concentration in the house, accerated vegetative growth, and the least chlorophyll content. There were no significant difference in photosynthetic rate, transpiration rate, maximal photochemical efficiency and antioxidant enzyme activities of all temperature treatments in this experiment. However it was clear that a little difference in error range of these results affects the source of crops in any case. It was not acknowledged that compensation effect by high temperature in daytime to the low temperature treatment in nighttime.

• Journal of Plant Biotechnology
• /
• v.32 no.1
• /
• pp.23-29
• /
• 2005

Shoots of balloon flower (Platycodon grandiflorum A. DC.) derived from in vitro germinated seeds were cultured on MS medium containing $0.1\;\cal{mg/L}$ NAA under various photosynthetic photon flux (PPF) 33, 66, and $99\;{\mu}mol\;m^{-2}s^{-1}$ with or without membrane filter. Number of air exchanges per hour (NAEH) of the culture vessel with membrane filter on the lid was $4.9 h^{-1}$ and that without membrane filter was $0.1 h^{-1}$ Plantlets grown in $4.9 h^{-1}$ NAEH showed greater growth than in $0.1 h^{-1}$ NAEH. According to increase of PPF, plantlets growth decreased in $0.1 h^{-1}$ NAEH while it increased in $4.9 h^{-1}$ NAEH. At the same PPF, fresh weight and sugar content in plantlets in $4.9 h^{-1}$ NAEH were above 1.9, 2.0 times higher than those in $0.1 h^{-1}$ NAEH, respectively. Also they were enhanced in $4.9 h^{-1}$ NAEH by increase of PPF whereas no significance in $0.1 h^{-1}$ NAEH. The percentage of water content of plantlets in $4.9 h^{-1}$ NAEH was $4.2\~5.5\%$ lower than those in $0.1 h^{-1}$ and no difference in PPF. The content of total chlorophyll in plantlets in $4.9 h^{-1}$ NAEH was higher $0.27\~0.79\;\cal{mg/g}$ F.W. than that in $0.1 h^{-1}$ NAEH. By increase of PPF, it was decreased in $0.1 h^{-1}$ NAEH while had no significant difference in $4.9 h^{-1}$ NAEH. Guard and subsidiary cells of leaves in $4.9 h^{-1}$ NAEH were more developed than in $0.1 h^{-1}$ NAEH. Especially, in $99\;{\mu}mol\;m^{-2}s^{-1}$ leaves in $0.1 h^{-1}$ NAEH had undeveloped subsidiary cells and wide open stomata whereas those in $4.9 h^{-1}$ NAEH had well-developed subsidiary cells.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.19 no.2
• /
• pp.109-124
• /
• 2014

In order to understand the carbon cycle in the Amundsen Sea of the Southern Ocean, the export fluxes of particulate organic carbon from the euphotic zone to deep water estimated using ${\psi}$/${\psi}$ disequilibrium method. Seawaters in 14 water columns were collected during February and March 2012, and analyzed for total and dissolved ${\psi}$, and particulate organic carbon. Total ${\psi}$ activities in the water column showed deficiency and excess relative to those of ${\psi}$ depending on the water depth. Deficiency of total ${\psi}$ in the euphotic zone showed mirror images both with chlorophyll-a and fluorescence, and was consistent with the loss of nitrate, which indicated the effect of biological activity. In addition, deficiency of total ${\psi}$ from deep water was associated with the increase of total dissolvable Fe/Mn concentration. Excess total ${\psi}$ activity presented below the euphotic zone might be related to particulate ${\psi}$ concentrated in this water depth. Mean export flux of ${\psi}$ estimated using the steady state model was $867{\pm}246dpmm^{-2}day^{-1}$. Mean export flux of particulate organic carbon, which were estimated by the product of total ${\psi}$ flux and ratio of POC/${\psi}$ ($7.08{\pm}4.27{\mu}molCdpm^{-1}$) in the sinking particles, was $5.9{\pm}3.9mmolCm^{-2}day^{-1}$. These fluxes were similar levels to those in the Weddell Sea during February and March 2008. Export ratios (ThE) relative to the primary production in the euphotic zone were in the range of 3-54% (av. 28%).

• Horticultural Science & Technology
• /
• v.30 no.6
• /
• pp.664-672
• /
• 2012

As an artificial light source, light-emitting diode (LED) with a short wavelength range can be used in closed-type plant production systems. Among various wavelength ranges in visible light, individual light spectra induce distinguishing influences on plant growth and development. In this study, we determined the effects of monochromatic LEDs on leaf shape index, growth and the accumulation of phytochemicals in a red leaf lettuce (Lactuca sativa L. 'Sunmang') and a green leaf lettuce (Lactuca sativa L. 'Grand rapid TBR'). Lettuce seedlings grown under normal growing conditions ($20^{\circ}C$, fluorescent lamp + high pressure sodium lamp, $130{\pm}5{\mu}mmol{\cdot}m^{-2}{\cdot}s^{-1}$, 12 hours photoperiod) for 18 days were transferred into incubators at $20^{\circ}C$ equipped with various monochromatic LEDs (blue LED, 456 nm; green LED, 518 nm; red LED, 654 nm; white LED, 456 nm + 558 nm) under the same light intensity and photoperiod ($130{\pm}7{\mu}mmol{\cdot}m^{-2}{\cdot}s^{-1}$, 12 hours photoperiod). Leaf length, leaf width, leaf area, fresh and dry weights of shoots and roots, shoot/root ratio, SPAD value, total phenolic concentration, antioxidant capacity, and the expression of a key gene involved in the biosynthesis of phenolic compounds, phenylalanine ammonia-lyase (PAL), were measured at 9 and 23 days after transplanting. The leaf shape indexes of both lettuce cultivars subjected to blue or white LEDs were similar with those of control during whole growth stage. However, red and green LEDs induced significantly higher leaf shape index than the other treatments. The green LED had a negative impact on the lettuce growth. Most of growth characteristics such as fresh and dry weights of shoots and leaf area were the highest in both cultivars subjected to red LED treatment. In case of red leaf lettuce plants, shoot fresh weight under red LED was 3.8 times higher than that under green LED at 23 days after transplanting. In contrast, the accumulation of chlorophyll, phenolics including antioxidants in lettuce plants showed an opposite trend compared with growth. SPAD value, total phenolic concentration, and antioxidant capacity of lettuce grown under blue LED were significantly higher than those under other LED treatments. In addition, PAL gene was remarkably activated by blue LED at 9 days after transplanting. Thus, this study suggested that the light quality using LEDs is a crucial factor for morphology, growth, and phytochemicals of two lettuce cultivars.

• Horticultural Science & Technology
• /
• v.28 no.4
• /
• pp.574-579
• /
• 2010

Waste nutrient solution (WNS) that was the drained nutrient solution of Horticultural Research Institute of Japan for culture tomato in perlite hydroponics showed $1.9-2.4dS{\cdot}m^{-1}$ of EC and 5.7-7.1 pH from April to July. Although ${NH_4}^+-N$ concentration of WNS decreased remarkably, the other nutrients did not change significantly, as compared with supplied solution. There were no significant differences in plant height, stem diameter, and the other growth characteristics of tomato plants grown by 2 fertigation nutrient solutions; BHF (Bountiful Harvest Fertilizer, 10% of N, 13% of $PO_4$, 13% of K, 0.05% of B, 0.05% of Zn, and 0.0023% of Cu that made in Korea) and Megasol (11% of N, 8% of $PO_4$, 34% of K, 0.032% of Mn, 0.002% of B, 0.048% of Fe, 0.0122% of Zn, and 0.0023% of Cu that made in Belgium.); however, the chlorophyll content of tomato leaf was highest in WNS. The fresh and dry weight of tomato plants were higher in 3 fertigation treatments than irrigation of tap water, while there were no significant differences in fresh and dry weight among the 3 fertigation treatments. The mineral content of tomato leaf also did not show any differences among the 3 fertigation treatments and any regular tendency in all minerals. Total yield, fruit weight and fruit numbers of tomato were higher in WNS, followed by Megasol, BHF and control, although there were not any difference among the 3 fertigation nutrient solution treatments. BER(blossom-end rot)of tomato fruits decreased in fertigation treatments, especially, fruits grown in WNS and BHF showed lower BER. However, the transpiration rate of leaf was higher in control, followed by BHF, WNS and Megasol, The fruit size and soluble solids content was higher in 3 fertigation nutrient treatments than control. These results suggest that WNS can be used for fertigation solution in tomato because yield and quality of tomato fruit grown in WNS fertigation treatment were similar to those in 2 fertigation nutrient solutions treatments(BHF, Megasol).

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.41 no.4
• /
• pp.465-474
• /
• 1996

The study was carried out to determine the proper concentration of plant growth regulator, kinetin on alleviating copper toxicity for two rice cultivars of seed germination. The results were as followings : Soaking treatment of kinetin 10$^{-3}$ M increased the germination rate of both cultivars, Ilpumbyeo and Hyangmibyeo 1 by 92% and 88% as compared with copper treatment (60ppm). But the soaking treatment effect of plant growth regulator, kinetin was not recognized at the kinetin 10$^{-4}$ M and 10$^{-5}$ M. Chlorophyll content of both rices was higher than that of Hyangmibyeo 1. Copper content of Ilpumbyeo was higher in leaf than in seed part. At the 3 days after treatment of copper 60ppm, both cultivars of treatment of kinetin 1O-3M showed the somewhat thin bands at the 35 and 40kDa compared with others. A new protein band pattern was only appeared to kinetin 1O-3M at approximately 54.4kDa(M. W) at the 7 days after treatment of copper 60ppm in llpumbyeo cultivar, SOD activity of copper 60ppm treatment increased in 3DAT, but there were no significant differences in 5 and 7DAT of two cultivars. Free proline contents of copper 60ppm treatment in llpumbyeo were remarkably increased about 4.996$\mu$M. In particular, free proline content of kinetin l0$^{-3}$ M in Ilpumbyeo was 5.008$\mu$M in 3DAT. In case of Hwangmibyeo 1, free proline content of copper 60ppm was 5.825$\mu$M compared with an untreated control showing 2.34l$\mu$M. The effects of kinetin treatment were recognized to promote the root growth and germination rate under copper toxicity(60ppm) condition in both cultivars.