• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.4
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• pp.94-99
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• 2009

The purpose of this study was to utilize hydroculture by the vital means of the improvement of indoor relative humidity. This experiment employed a search of the effect of Scindapsus aureus and Syngonium podophyllum that are generalized for hydroculture foliage plant by a difference of volume ratio, pot media and plants species. In the case of Scindapsus aureus, relative humidity was high for growth chamber in which plants presented as opposed to control growth chambers in which there were no plants. Although relative humidity was 25% in control chamber, there was an increase of 40% at a 2% volume ratio, 45% at a 3% volume ratio and 50% at a 5% volume ratio. The relative humidity of Syngonium podophyllum was 40% at a 2% volume ratio, 44% at a 3% volume ratio and 46% at a 5% volume ratio, while the control treatment was 25% relative humidity in hydroculture. Both the control treatment and hydroball pot in a hydroball container were high at first. As time progressed, artificial soil pots in water containers was similar when housed within the control chamber by about 45% relative humidity. Hydroball pots in water container had about 30% relative humidity. Ardisia pusilla of hydroball poIt in hydroball container had about 38% relative humidity.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.102.2-103
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• 2003

This studies were investigated the occurrence of Sclerotinia rot by Sclerotinia Sclerotiorum at the lettuce field in Uiryeong-Gun, Gyeongsangnam-Do and were isolated the most effective microorganism for the biological control to the pathogen, S. sclerotiorum YR-1 strain from diseased soil and lettuce leaves. For the pathogenicity test, the most suitable inoculmn density of YR-1 strain was selected as the mycelial suspension of 40m1 showing disease incidence of 80％, and the symptom showed as same as at the fields, the leaves and stem had rotten and developed white downy mycelial at the diseased lesion on the leaves and stems, and produced black and irregular sclerotinia. On the PDA dual test, about 300 isolates were examined the antifungal activity to the pathogen, YR-1 strain, and among them, A-2, A-7, and RH-4 strain were selected most effective antagonistic bacteria. At pots test, the control value of A-7 strain showed the highest value as 85％ which was more effective than that of others in a growth chamber. For the promotion of control effect, the selected 3 isolates were spayed on the lettuce leaves as a sole and/or mixed treatments in a growth chamber, the mixed treatment of A-7 and RH-4 strain showing the control value of 90％ was most effective than that of sole treatment with A-7 or RH-4 strain showing the control value of 80％, respectively and mixed treatment with A-2 and A-7 strain and A-2, A-7 and RH-4 strain. In addition, 3 bacteria re-isolated from diseased soils, and all of the selected 6 isolates investigated the control effect at pots in a growth chamber, According to the results, A-7 and Pro-EB 15 strain showed the control value of 91.0％ and 90.1％ respectively, and they were selected most effectual antagonistic bacteria to control lettuce sclerotinia rot and identified as the Bacillus mojanuinensis by 16s RNA analysis. This is the first report on the biological control using by B. mojanvinensis to the lettuce Sclerotinia rot.

• Korean Journal of Environmental Biology
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• v.29 no.4
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• pp.373-378
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• 2011

Our aim was to investigate the genotoxicity of ambient air in the Krak$\acute{o}$w area after Fukushima Nuclear Power Plant (NPP) accident and compare with results from Chernobyl fallout. For the detection of ambient air genotoxicity the technique for screening gene mutation frequency in somatic cells of the $Tradescantia$ stamen hairs ($Trad$-SH assay) was used. Since 11th of March 2011 (Fukushima NPP accident), several pots containing at least 15 shoots of bioindicating plants were exposed to ambient air at 2 sites in the Krak$\acute{o}$w surrounding area, one in the city center, and about 100 pots in a control site (in the glasshouse of the Institute of Nuclear Physics) Continuous screening of mutations was performed. Progenies of 371,090 cells exposed were analyzed. Mutation frequency obtained in the first 10 days has shown a mean control level (GMF*100=$0.06{\pm}0.01$). At scoring period related to influence of a potential Fukushima fallout, a significant increase of gene mutation frequencies above the control level was observed at each site in the range, 0.10~0.33 depending on the location, (mean value for all sites GMF*100=$0.19{\pm}0.05$) that was associated with a strong expression of toxic effects. In the reported studies following the Chernobyl NPP accident monitoring $in$ $situ$ of the ambient air genotoxicity was performed in the period since April $29^{th}$ till June $3^{rd}$ 1986 also with Trad-SH bioindicator. In general, mutation frequency increases due to Chernobyl fallout(GMF*100=$0.43{\pm}0.02$) were corresponding to fluctuation of radioactivity in the air reported from physical measures, and to published reports about increase in chromosome aberration levels. Although, recent data obtained from monitoring of the ambient air quality in the Krak$\acute{o}$w and surroundings are lower when compared to results reported after Chernobyl NPP accident, though results express a significant increase above the control level and also are corresponding with increased air radioactivity reported from physical measurements. Statistically significant in comparison to control increase in gene mutation rates and more prolonged than that after Chernobyl fallout increase of GMF was observed during the period following the Fukushima NPP failure.

• Journal of Soil and Groundwater Environment
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• v.6 no.4
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• pp.25-40
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• 2001

In order to investigate the degree of heavy metal pollution, 280 urban gully-pot sediments were collected from 13 localities in eastern part of Seoul. The uncontaminated stream sediments were also studied for comparison. A series of studies have carried out concerning the physicochemical characteristics of the sediments and the distribution of Cd, Co, Cr, Cu, Ni, Pb, and Zn. Total metal concentrations of gully-pot sediments and uncontaminated stream sediments were analyzed using acid extraction. After predigestion with $NHO_3$, the sample was digested with mixed acid ($NHO_3$-$HClO_4$). The gully-pot sediments were characterized by very high concentrations of Zn, Cu, Pb and Cr, indicating an anthropogenic contribution of these metals to the sediment chemistry Heavy metal concentrations in the gully-pot sediments were 1-329 times higher than the mean content of metals in the uncontaminated stream sediments, depending on the metals. In particular, the highest mean concentrations of Zn, Cu, Pb and Cr were noticed in the gully-pot sediments from Yeouido, Junggu, Junggu, and Dongdaemungu, respectively. The mean value of total Zn concentration in the business and commercial areas is 2-3.5 times higher than that in industrial areas. This suggests that Zn is mainly derived from automobiles (rubber of automobile tires). The mean concentrations of Cu and Cr are significantly high in the commercial and industrial areas, indicating that industrial activities may cause the accumulation of Cu and Cr in the sediments. The Pb level in gully-pot sediments is comparatively low, due to the use of unleaded gasoline in automobiles since 1987.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.1
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• pp.29-34
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• 1987

This experiment was designed to find out the effects of soil conditioner, Polyacrylamide (PAM) and Bitumen, on the changes of soil aggregate properties and crop yields. The soil conditioners were treated at the rates of 0.5% and 1% to sandy loam and silty clay loam soils. The aggregate stability, wetting angle, mean weight diameter and air permeability were analyzed. Pot experiments were carried out to investigate the soybean growths and soil property changes after the soil conditioners were sprayed to surface soils. Soil aggregate stability was increased remarkably by the soil conditioner, PAM and Bitumen, treatments. PAM was more effective in sandy loam than silty clay loam, but Bitumen was better in silty clay loam. Wetting angle of the soil was changed slightly by PAM treatment, but it was greatly changed to hydrophobic by Bitumen treatment. Air permeability, water infiltration rate and moisture retention of the soils were increased by surface application of soil conditioners, PAM and Bitumen. The growths of soybean in conditioner applicated pots were better than those of untreated pots from early stage, and the yields were increased 6-13%.

• Journal of Bio-Environment Control
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• v.11 no.1
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• pp.12-17
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• 2002

Tn establish the criteria for appropriate seedling production method in the summer, the effect of container size and seedling age on the growth and yield were evaluated with tomato. The seedling quality was higher when seedlings were grown polyethylene in 9cm pots than in 72 cell plugs. Seedling quality increased with increase in seedling age in polyethylene pots, whereas seedling age did not affect seedling quality in plug trays. Fruits matured earlier on plants started from pot-grown transplants for a long duration than with plug tray-grown transplants for a shorter duration. Not only total yield in 4 months, but the early yield in the first 2 months, was higher with pot-nursed transplants than with plug tray-nursed transplants. With pot-grown transplants, The early yield in initial 2 months was the lowest in 25 day-old transplants, whereas there was no significant differences between 35- and 45-day-old transplants. Seedling age did not affect the cumulative yield for 3 months after the first harvest. With plug tray-grown transplants, the cumulative yield tar initial 3 months was the highest in plants grown for 35 days in the nursery, followed by 25 day and 45 day. However, there were no significant differences among seedling ages in the total yield.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.38 no.3
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• pp.202-208
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• 2002

Test fishing was carried out utilizing a coastal pot-fishing boat from IS March to 7 April 2002 and the results obtained are summarized as follows ; 1. Mean catches(Number of sea eels) according to the soak time of 3 hours, 6 hours and 12 hours were 44.6, 60.0 and 83.3, and CPUE(Number of catch / 10pots·hour) were 2.5, 1.7 and 1.1 respectively 2. Catch difference between over 24 hours and 48 hours was 11.3% and 3.3% between over 48 hours and 72 hours. 3. In the test fishing, by-catches were so low(1.5∼3%) until 12 hours of soaking time passed By-catches were increased according to the soaking time addition on the over 24 hours of soaking time. The bait effect for sea-eel seems to be diminished as soon as the casting started and there was big difference in proportion to bait size and freshness.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.47 no.4
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• pp.316-326
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• 2011

In this study, the entrapped number is investigated on the UV light with different illuminance to fluorescent bait cage for swimming crab in order to find the appropriate illuminance which has the best attraction effect of fluorescent bait cage for pots. In addition, preference to the light, arrival time and residence time at light area are compared and analyzed to fluorescent bait cage and non-fluorescent bait cage for American lobster at the UV light and ordinary light according to the illuminance condition. Pot with red non-fluorescent bait cage at the no lighting (<0.01lux), pot with blue fluorescent bait cage at the 20W UV lighting (0.16lux) and pot with blue fluorescent bait cage at the 30W UV lighting (0.22lux) were soaked for 6 hours and the entrapped number of swimming crab was examined. The mean entrapped number of swimming crab in pot with red non-fluorescent bait cage at the no lighting (<0.01lux) was 1.0, but the mean entrapped number of swimming crab in pot with blue fluorescent bait cages at the 20W UV lighting (0.16lux) and 30W UV lighting (0.22lux) were 1.4 and 0.4, respectively (P<0.05). The rate of preference to the blue fluorescent bait cage at the UV lighting shows 1.6-4.8 times higher than that of preference to the red non-fluorescent bait cage at the ordinary lighting. In addition, The rate of preference to the blue fluorescent bait cage at the UV lighting is higher when the illuminance of ordinary light is same as or is lower than that of UV light (P<0.05). However, the preference to the light depending on gender shows no significant difference (P>0.05). The arrival time to UV light area of lobster is shown as 1.2-2.4 times faster than that to ordinary light area. Generally, it is shown that arrival time to UV light area is faster than the arrival time to ordinary light area when the illuminance of ordinary light is the same as or lower than that of UV light (P<0.05). However, arrival time to the light area depending on gender shows no significant difference (P>0.05). The residence time at UV light area of lobster is 1.2-1.7 times longer than that at ordinary light area. The residence time depending on different illuminance of ordinary light and genders showed no significant difference (P>0.05).

• Magazine of the Korean Society of Agricultural Engineers
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• v.28 no.2
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• pp.31-41
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• 1986

Knowledge of the degree of yield reduction due to water stress at different crop growth stages in rice production is important for rational scheduling of irrigation during periods of insufficient water supply. Previous studies to determine the degree of yield reduction duo to water stress suffered from interruptions by rain during experiment. Also the findings did rot relate the degree of water stress to the soil water potential and water deficit status of rice plants. In this study, two years experiments were conducted using the high yielding rice varieties, an Indica x Japonica (Nampoong) and a Japonica variety(Choochung). These were grown in 1/200$^{\circ}$ plastic pots placed under a rainfall autosensing, sliding clear plastic roof facility to control rainfall interruptions. The results obtained were as follows. 1.The two varieties differed in the growth stage most sensitive to water stress as well as the degree of yield reductions. When rice plants were stressed to the leaf rolling score 4 and soil water potential of about - 20 bar at major crop growth stages which included heading, booting, non-effective tillering, panicle initiation and early tillering stages, the yield reductions in the Indica x Japonica variety were 58%, 34%, 27%, 22%, and 21%, respectively, whereas in the Japonica vairety they were 23%, 36%, 1%, 13% and 22%, respectively. This result show that the recommended drainage during non-effective tillering is valid only for the Japonica variety. Sufficient irrigation at booting, heading and early tillering stages are necessary for both varieties. 2.The two varieties showed visible wilting symptoms when the soil water potential dropped to about - 3.0 bar. The Japonica variety showed more leaf rolling than the Indica X Japonica. However, it had a higher retention of leaf water content and greater stomatal diffusive resistance. When the soil water potential dropped, the Japonica variety showed leaf rolling score (LRS) 1 at 0 soil-5. 0 bar and LRS 2 at 0 soil -6.0 bar while the Indica X Japonica showed LRS 1 at 0 soil - 5.5 bar and LRS 2at 0 Soil - 9.0 bar. The stomatal diffusive resistance was maximum at the second top leaf blade in both varieties at intermediate water stress of 0 soil - 4.5 bar. 3.The number of days that was required for the soil water potential to drop to-3. 0 bar and to - 20.0 bar after drainage of irrigation water from the 20cm deep silty clay loam soil in the pots were 6 and 13 days, respectively for booting stage, and 7 and 11 days, respectively for heading stage, 9 and 12 days, respectively for panicle initiation stage, and 12 and 19 days, respectively for early tillering stage. 4.Water stress during the early tillering stage recorded the longest delay in beading time, the largest reduction in panicle numbers and a substantial yield decrease of 20%. This calls for better water management to ensure the availability of water at this stage, particularly during drought periods. In addition, a reexamination of the conventional inter-drainage practice during the non-effective tillering stage is necessary for the high yielding Indica X Japonica varieties.

• The Korean Journal of Soil Zoology
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• v.8 no.1_2
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• pp.23-26
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• 2003

A neem based product, Suneem-G (granules) alone as well as in combination with urea was tested against root-knot nematode, Meloidogyne incognita, on okra (Abelmoschus esculentum) in clay pots of 20-cm-diameter, containing 2 kg sterilized soil, inoculated with 2,000 freshly hatched second stage juveniles (J$_2$) of M. incognita. Application of different dosages of Suneem-G with or without urea significantly reduced nematode population and incidence of galling on okra roots and increased vegetative plant growth compared with the untreated control. Suneem-G with urea was the most effective and its effect increased with the increase of dosage. Suneem-G 6 g＋urea 25 g per pot gave maximum plant growth and root gall reduction, as plants shoot and root lengths were increased by 84 and 58% and root galling was reduced by 58%, respectively. The lowest dosage of Suneem-G alone, 2 g per pot increased shoot and root lengths of plants by 25.7 and 17%, respectively, and reduced root galling by 24%. The lowest effect was recorded in the pots treated with 25 g urea alone; shoot and root lengths were increased and root galling was decreased by 14% each.