• Journal of Bio-Environment Control
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• v.16 no.4
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• pp.358-364
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• 2007

This study was carried out to investigate the effect of phosphorus concentrations in fertilizer solution on growth and development of nutrient deficiency in leaf perilla (Perilla frutesens). The nutrient concentrations in above ground plant tissue, petiole sap and soil solution of root media were also determined. Phosphorus deficiency resulted in a slow growth, lustreless leaves, suffused purple tining in older leaves and falling prematurely. Elevation of P concentrations in fertilizer solution increased the crop growth at 75 days after transplanting. The fresh weight in 0, 0.5 and 4.0 mM treatments were 0.48 g, 9.28 g, and 25.5 g, respectively, and dry weights were 0.06 g, 1.46 g and 4.13 g, respectively. The P concentrations in above ground plant tissue and petiole sap in 4.0 mM treatment were 1.78% and $2.040mg{\cdot}kg^{-1}$, respectively, at 75 days after transplanting. The soil P concentration in 4.0 mM treatment was $1.26mg{\cdot}kg^{-1}$ when it was determined by the 1:2 (sample:water) method. These results indicated that P concentrations higher than 0.3% in above ground plant tissue, $900mg{\cdot}kg^{-1}$ in petiole sap, and $0.57mg{\cdot}kg^{-1}$ in soil solution should be maintained to ensure proper growth of leaf perilla (Perilla frutesens).

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.225-231
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• 2009

'Nokkwang' green pepper plants were grown in soil system (silty loam with pH 6.5) under the greenhouse, to determine the effects of subsurface drip irrigation (SDI) and subsurface drip irrigation plus aeration (SDIA) into root zone comparing with conventional surface drip irrigation (DI) in terms of water use efficiency, soil properties, and growth and fruit yield. Two drip lines per crop row were layed on the soil surface in DI system, buried at a depth of 20cm below the soil surface in SDI system, and also buried at a depth of20cm below the soil surface and aerated for 3minutes a hour during the daytime ($08:00{\sim}19:00$) by a air compressor in SDIA system. A automatic irrigation with starting point of -20kPa and ending point of -10kPa based on soil moisture contents was applied by controllers and electronic vacum soil moisture sensors. Reduction in soil moisture contents was delayed in SDI and SDIA, compared to DI. Irrigation amount applied in pepper cultivation was around 30% less in SDI than in DI. Electric conductivity and nitrate nitrogen content in the surface soil grown green pepper were significantly lowered in SSDI and SDIA, compared to DI. Better development of root system was observed in SDIA and SDI than in DI. Results showed that pepper fruit yield increased by 30% in SDIA and 22% in SDI in comparision with DI.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.240-245
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• 2010

The objective of this study was to determine the effect of different height of drainpipe and growing media soilless cultivated cut rose in container culture. Two experiment were to examine the effect of the drainpipe height and media composition on yield and quality of cut rose, Four different drainpipe height (0, 3, 6, 9 cm) were treated to determine of optimal container type. Yield was the highest at 3 cm drainpipe height, but quality was not significantly affected by drainpipe height. Survival rate of rose was 100%, 100%, 92%, and 92%, respectively. Two different drainpipe height (0, 3 cm) and 7 media composition (pure coir and pelite, and mixed with two media 3 : 1, 2 : 1, 1 : 1, 1 : 2, 1 : 3 v/v) was treated to determine of media composition related to drainpipe height. The supply of nutrient solution was controlled by the signal of water potential at -5 kPa using frequency domain reflectometry (FDR) sensor in mixed coir with pelite 3 : 1, 1 : 1, 1 : 3 (v/v), respectively. Irrigation frequency reduced in high ratio of coir media and 3 cm height of drainpipe. Quality of cut rose except for flower weight and yield until 2nd harvest was not significantly affected by drainpipe height, but yield after 3rd was higher at 3 cm than 0 cm height of darinpipe. In the media composition, yield and qulity of cut rose was increased at high ratio of coir media.

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.273-279
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• 2009

This study was conducted to identify optimal concentrations of N (nitrogen) and K (Potassium) fertilizers on growth, yield and quality of melon (Cucumis melo. L) when they were grown with a fertigation culture in a greenhouse. Three strength (S) levels of fertilizers, including 1 S, 1/2S, and 1/4S were supplied N and K nutrients as using a trickle irrigation system. When the strength level of fertilizers was increased from 1/4S to 1 S, the level of EC (electronic conductivity) in soil was increased. Soil-water tension was ranged between -15 and -20kPa until fruit setting stage, whereas it was ranged between -45 and -50kPa in the later growth stages. In results, N fertilizer had effects on fruit yield and quality. A higher fruit yield was observed when plants were supplied with 1 S and 1/2S level of N fertilizer. The highest yield of marketable fruit, about 5,086kg/10a, was also observed when plants were supplied with 1/2S N fertilizer. A higher net index and sugar content of fruit was observed in the treatments of 1/2S and 1/4S level of N fertilizer compared to 1 S level. In contrast, there was no statistic difference in the yield and quality with three levels of K fertilizer. Results indicate that the 1/2S level for N and 1/4S level for K fertilizer are effective and optimal for the melon plants grown under the fertigation culture in terms of increasing fruit yield and quality and reducing the cost of fertilizers.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.217-222
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• 2010

Bark is a general medium for potted Cymbidium in Korea, but it is difficult to shake off or eliminate the medium from the roots before exporting the potted plants. This working process can injure the roots and then deteriorate plant marketability. This study was carried out to select the optimum medium easier to eliminate from the roots instead of bark and the optimum amount of applied fertilizer to improve the plant growth. Cymbidium young plants 'Honey Hot' and 'Desert Look' were planted in pots with bark, cocochip, and peatmoss. The plants were treated with 2, 4, and 6 g of slow release fertilizer. The plant growth characteristics were investigated in the first and second years during production period of three years. The medium characteristics and mineral nutrient content of the leaves were also examined in the second year. In the first year, the plant growth of 'Desert Look' was improved in all peatmoss treatments more than bark. 'Honey Hot' showed the highest plant growth values in the bark treatment. In the second year, the plant growth of the two cultivars was improved in peatmoss. Cocochip treatments showed the lower plant growth values than bark and peatmoss in the first and second year. There was no significant difference among fertilizer amounts in all the media. The higher CEC values of peatmoss medium resulted to higher capacity to hold more nutrients than bark, and the nutrient retention of the peatmoss improved the plant growth. The higher K and Ca contents in the leaves would contribute to improve the plant growth. Consequently, it would be possible to use peatmoss instead of bark for Cymbidium young plants, but there must be always attention to appropriately water the medium and manage the moisture.

• Journal of Bio-Environment Control
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• v.23 no.2
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• pp.95-108
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• 2014

The objective of this study is to develop the plastic greenhouse models which are structurally safe under the weather condition of Seongju and have the dimensions suitable for oriental melon cultivation as well. To grasp the structural features of greenhouses in Seongju, the field survey was conducted on 406 farmhouses which included 2,068 greenhouses. The field survey showed that the roof shape of arch type accounted for the highest rate, but recently even span or peach type became more popular and the width and height of greenhouse tended to increase as the period of use was short. The relationship of the width, ridge height and eaves height were established based on field survey data. Using climate data of Gumi adjacent to Seongju, the regressions were determined for the design wind speed and design snow depth depending on recurrence period. To design the greenhouse models against weather disasters in Seongju, the optimal design loads are 23.7 cm of snow depth and $33.8m{\cdot}s^1$ of wind speed. As the design results, four models of single-span greenhouse, two models of double-span greenhouses including extension were developed.

• Parasites, Hosts and Diseases
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• v.56 no.4
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• pp.341-349
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• 2018

The infection status of Centrocestus armatus metacercariae (CaMc) was broadly surveyed in freshwater fishes from major river systems in the Republic of Korea (Korea) during 2008-2017. A total of 14,977 fishes was caught and examined by the artificial digestion method. CaMc were detected in 3,818 (97.1%) (2,114 Z. platypus: 96.1% and 1,704 Z. temminckii: 98.4%) out of 3,932 Zacco spp. examined and their density was 1,867 (2,109 in Z. platypus and 1,567 in Z. temminckii) per fish infected. The prevalences with CaMc were high, 93.7-100%, in Zacco spp. from all surveyed areas. However, their densities were more or less different by the surveyed areas and fish species. They were most high in Nakdong-gang in Gyeongsangnam-do (4,201 in average), and followed by Geum-gang (2,343), Nakdong-gang in Gyeongsangbuk-do (1,623), Han-gang (1,564), Tamjin-gang and Yeongsan-gang (1,540), streams in the east coast (1,028), Seomjin-gang (488) and Mangyeong-gang (170). In another species of rasborinid fish, Opsariichthys uncirostris amurensis, CaMc were detected in 222 (74.8%) out of 297 ones examined and their density was 278 (1-4,480) per fish infected. CaMc were also detected in total 41 fish species except for the rasborinid fish, Z. platypus, Z. temminckii and O. uncirostris amurensis. Conclusively, it was confirmed that among the 3 species of rasborinid fish, Z. platypus and Z. temminckii are highly prevalent and O. uncirostris amurensis is moderately prevalent with CaMc. Additionally, we could know that variety of fish species act as the second intermediate hosts of C. armatus in Korea.

• Journal of Life Science
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• v.19 no.3
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• pp.390-396
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• 2009

In this study, extracts from S. officinalis were tested for antioxidative effects and inhibitory activities against $\alpha$-amylase, angiotensin converting enzyme (ACE) and xanthine oxidase (XOase). The content of total phenolic compounds in water, 60% ethanol, 60% methanol and 60% acetone extracts were 36.2, 42.7, 40.3 and 39.6 mg/g, respectively. In 60% ethanol extracts, the EDA by DPPH free radical scavenging test of S. officinalis was $66.3{\pm}2.2%$ at $200{\mu}g/ml$. The inhibition rate of ABTS was $97.6{\pm}0.1%$, the antioxidant protection factor was $2.26{\pm}0.63$ PF, and TBARS was $0.62{\pm}0.05$ (${\times}100{\mu}M$ in the control and $0.29{\pm}0.02$ (${\times}100{\mu}M$). Also in 60% ethanol extracts of S. officinalis, the inhibitory activity against XOase was 78% and was not shown to be against ACE. According to the $12.6{\pm}0.14\;mm$ of clear zone formed, the inhibition rate against $\alpha$-Amylase was 7.6% at $200{\mu}g/ml$ of phenolics content. Antimicrobial activities of 60% ethanol extracts of S. officinalis against Helicobacter pylori exhibited an inhibition rate of $12.5{\sim}66.1%$ according to the $10{\sim}15\;mm$ of clear zone at $50{\sim}200{\mu}g/ml$. The results suggest that the 60% ethanol extracts from Salvia officinalis L. will be useful as natural antioxidants and functional food sources.

• Journal of Life Science
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• v.20 no.9
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• pp.1345-1352
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• 2010

We investigated the effect of brown-rice vinegar (BRV) ingestion after strenuous Wingate tests on energy substrates during a 2 hr recovery period. For this, seven healthy male adolescents were chosen as subjects. They performed 3 Wingate tests to induce fatigue, after which they ingested brown-rice vinegar (BRV) drink and/or water as a control (CON) after 15 min of the test. Blood was obtained pre-exercise and 30 min, 60 min, and 120 min post-exercise, and blood glucose, lactate, free fatty acids, ammonia, and cortisol were analyzed. After 120 min of recovery period, the 4th Wingate test was conducted to calculate the power recovery ratio of the 3rd and 4th trials. Breathing frequency, oxygen saturation, and heart rate did not show significant changes. Blood glucose level was lower in CON than BRV after 120 min of recovery, and blood lactate and ammonia levels were lower in BRV at 60 and 120 min. The higher free fatty acids were found at 60 and 120 min in BRV. In addition, Wingate power recovery ratio of peak power and peak power/body weight was significantly higher in BRV compared to CON. These results suggested that BRV ingestion after strenuous exercise facilitates fatigue recovery. Therefore, BRV might be effectively used as an ergogenic aid for events in which competitors compete two or more times a day.

• Journal of Life Science
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• v.30 no.6
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• pp.542-549
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• 2020

A previous study reported that Ulmus macrocarpa Hance water extract (UME) can improve hyperlipid metabolism and the involvement of suppressed lipid synthesis through adenosine monophosphate-activated protein kinase (AMPK) pathway regulation was suggested. Further exploration of the lipid metabolism between liver and peripheral tissue was necessary to confirm that work, and so this study aimed to extend the possibility that UME can regulate serum lipids. After a 6-week in vivo trial of oral administration of UME to rats with induced hyperlipidemia, serum levels of triglyceride (TG) and total cholesterol (TC) were seen to decrease while HDL cholesterol increased. The UME administrations also decreased the TC and TG levels from the control in liver analysis. However, the suggestion that UME regulates the AMPK pathway to improve hyperlipid states through the suppression of hepatic lipogenesis seems to be only one part of the extract's effect. Indeed, serum concentrations of apolipoproteins A and B were returned to baseline levels of the control group in response to UME administration whilst the liver lipid content was much reduced; this cannot occur through the suggested suppression of hepatic lipogenesis alone. Therefore, a possible mechanism of UME could be that it improves blood circulation by modulating serum lipid levels through both the prior stimulation of lipid oxidation and the suppression of hepatic lipogenesis.