• Korean Journal of Soil Science and Fertilizer
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• v.7 no.2
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• pp.99-105
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• 1974

According to the content of sugar and starch of each positional leaf sheath and internode at heading and 4 weeks after it using IR667-Suwon 214 (high yielding var. having tropical Indica parantage) and Jinheung (local leading var. temperate Japonica) rice grown in various cultivation seasons the suitability of grouping into the high sugar type (sugar>starch), sugar, tendency (increasing tendency in sugar content), high starh type (starch>sugar) and starch tendency (increasing tendency in starch) in carbohydrate metabolism was reexamined as follows. 1. Sugar tendency appeared strongly in IR667 than Jinheung, internode than leaf sheath, late season cultivation than early season, 4 weeks after than heading and high temperature than low temperature. Thus at heading, leaf sheath and internode of Jinheung in early and late season cultivation were high starch type, and lower internode in early season cultiattion and leaf sheath and internode in late season for IR667 were high sugar type. In very late season all internodes of both varieties except 1st internode of Jinheung at heading were high starch type. At four week after heading all leaf sheaths except 1st and 4th one of Jinheung and all internodes were high sugar type. High sugar type was intensified 4 weeks after heading in leaf sheaths than in internodes of IR667 in early season and of both varieties in late season. 2. The upper three leaf sheaths and internodes seem to work in the same way for carbohydrate translocation. Among them upper ones showed sugar tendency at heading and starch tendency 4 weeks after heading and it was clear in Jinheung. 3. The later the cultivation season, the higher the carbohydrate content (sugar+starch), and such tendency was clear 4 weeks after heading and in IR667, suggesting teanslocation inhibition by low temperature. 4. Grain filling rate (weight increase per day) was more rapid in early season cultivation and IR667 took shorter days to reach maximum rate. 5. The later the cultivation season, the greater the percent contribution of carbohydrate before heading to yield and it was always greater in IR667, a leaf sheath type. 6. Sugar and starch ratio appears to be determined principally by metabolic characteristics of variety according to growth process and secondly but considerably by environmental factors.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.3
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• pp.242-248
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• 1992

This study was carried out to investigate the effects of root-zone temperature in hydroponics on the plant growth and nutrient uptake of lettuce(Lactuca sativa L), tomato (Lycopersicon esculentum Mill), and cucumber (Cucumis sativus L). Respiration rate in roots increased with increase in root-zone temperature. At $10^{\circ}C$ of root-zone temperature, respiration rate in lettuce root was higher than those in tomato and cucumber. Increasing rate of root respiration in tomato with increase in root-zone temperature was greater than those in lettuce and cucumber. The lowest dry weight and leaf area of the crops studied were obtained at $10^{\circ}C$ of root-zone temperature, but they were not different between 20 and $30^{\circ}C$. Increase in root-zone temperature generally resulted in increase in T/R ratio and net assimilation rate. At the low root-zone temperature, root growth and leaf area of tomato and cucumber were severely affected. Relative growth rates of lettuce and cucumber were also greatly reduced by the low root-zone temperature. Contents of N, P, K, Ca, and Mg in the crops increased as root-zone temperature increased from 10 to $20^{\circ}C$, whereas only Ca content in tomato and cucumber increased with increase in root-zone temperature to $30^{\circ}C$. Remarkably low contents of P and Mg in the crops were found at the low root-zone temperature. Inhibition of plant growth and nutrient uptake due to low root-zone temperature was much greater in cucumber than in lettuce and tomato.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.2
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• pp.66-71
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• 2003

This study was carried out to obtain basic data for selecting the applicable crops in reclaimed land and to provide guidelines for the rotation between paddy and upland cropping. Field experiment was conducted with six summer crops(garland chrysanthemum, young radish, small radish, kale, lettuce, red lettuce) at Dae-Ho reclaimed experiment plots in Dangjin province. Dry weights and plant heights of harvested crops were measured and soil chemical properties were analyzed. Plant height and dry weight decreased significantly with increasing soil saturation paste extract electrical conductivity(ECe) and sodium adsorption ratio(SAR). The threshold ECe of salt inhibition for six crops was less than $1dS\;m^{-1}$ for young radish and kale, greater than $4dS\;m^{-1}$ for garland chrysanthemum, and greater than $6dS\;m^{-1}$ for small radish, lettuce, and red lettuce. At higher ECe that inhibits crop growth, with every increase in $1dS\;m^{-1}$, dry weight index decreased by 3.35 for kale, 3.92 for small radish, 3.98 for young radish, 4.66 for lettuce, 7.57 for garland chrysanthemum, and 8.45% for red lettuce, respectively. The ECe causing 50% reduction of dry weight index was $18.9dS\;m^{-1}$ for small radish, $17.3dS\;m^{-1}$ for lettuce, $15.4dS\;m^{-1}$ for kale, $12.0dS\;m^{-1}$ for red lettuce, $11.3dS\;m^{-1}$ for young radish, and $11.0dS\;m^{-1}$ for garland chrysanthemum. Among the tested 6 summer crops through field experiment and in-situ survey, kale was proved to be a favorable vegetable crop at reclaimed tidal land.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.2
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• pp.160-165
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• 2012

A field study was conducted at Miryang in 2011 to evaluate differential sensitivity of six rice cultivars, three Indica${\times}$Japonica rice (long grain, cv. Hanareumbyeo, Hanareum2, Dasanbyeo) and three Japonica rice (short grain, Nampyung, Ilpumbyeo and Junamjosaeng) cultivars, to benzobicyclon, mesotrione+pretilachlor (MP) and butachlor (control) in transplanting rice and their treatment influences on rice yield. All Indica${\times}$Japonica rice cultivars exhibited susceptible to both benzobicyclon and MP as reflected by higher visual injury and carotenoid biosynthesis inhibition when compared with Japonica rice cutlivars. The percentage of foliar chlorosis of Indica${\times}$Japonica rice was only 0.9~4.7% for benzobicyclon at 13 days after treatment (DAT) and 30.3~64.4% for MP at 5DAT but it increased rapidly to 88.4~91.2% at 12~20DAT. However, most of the Japonica cultivars are tolerant to bezobicyclon and MP. There was no visible leaf chlorosis but carotenoid biosynthesis was slightly inhibited. Based on relative carotenoid content reduction of benzobicyclon and MP to butachlor, the Indica${\times}$Japonica rice showed 4.6~15.6 fold higher compared with the Japonica rice. The heading date of the injured rice plant was delayed by 3 days and panicle number per square meter and ripened grain ratio were reduced as compared with the control treatment of butachlor. Rice yield of the Indica${\times}$Japonica rice cultivars treated with benzobicyclon and MP was reduced by 7~10%, 3~5%. respectively. The result indicates that rice cultivars vary in tolerance to HPPD-Inhibiting herbicides and Indica${\times}$Japonica rices were more susceptible than the Japonica rices to MP and benzobicyclon. Rice yield of the Indica${\times}$Japonica rices was also significantly reduced by the those herbicide treatments.

• The Korean Journal of Pharmacology
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• v.32 no.1
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• pp.39-49
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• 1996

In the present study, we observed change in intracellular $Ca^{2+}$$([Ca^{2+}]_i)$ as measured with the fluorescent $Ca^{2+}-indicator$ fura-2 in association with force development of the rat basilar arteries during activation by$K^+$ depolarizing solution and U46619, a thromboxane analogue, in the absence and the presence of calcitonin-gent related peptide (CGRP). CGRP (30 and 100 nM) caused a concentration-dependent inhibition of U46619-induced contraction with decrease in $[Ca^{2+}]_i$, whereas it did not exert any effect on the $K^+$ (90 mM)-induced contraction and increase in $[Ca^{2+}]_i$, Further, $[Ca^{2+}]_i-force$ relationships were determined by plotting the ratio of $F_{340}/F_{380}$ $([Ca^{2+}]_i)$ as a function of the force induced by U46619, and the results were compared with those obtained in the presence of CGRP. The curves obtained in the presence of CGRP (30 and 100 nM) were significantly moved to downward without right shift of the curves suggesting that CGRP inhibited the U46619-induced contraction only by mediation of reduction in $[Ca^{2+}]_i$ with out any change in the sensitivity of contractile apparatus to $Ca^{2+}$. The CGRP-induced attenuation of $[Ca^{2+}]_i$ and force development was significantly inhibited under pretreatment with CGRP $(8{\sim}37)$ fragment (100 nM), a CGRP1 receptor antagonist. Both the reduced contraction and reduction in $[Ca^{2+}]_i$ caused by CGRP were fully reversed by pretreatment with charybdotoxin (100 nM) and iberiotoxin (100 nM), large conductance $Ca^{2+}-activated$ $K^+$ channel blockers, but not by apamin (300 nM), a small conductance $Ca^{2+}-activated$ $K^+$ channel blocker, and glibenclamide ( 1 ${\mu}M$), an ATP-sensitive $K^+$ channel blocker. In conclusion, it is suggested that the CGRP1 receptor, upon activation by CGRP, are coupled to opening of $Ca^{2+}-activated$ $K^+$ channel and cause to decrease in $[Ca^{2+}]_i$, thereby leading to vasodilation of the rat basilar artery. However, it is not defined that the mechanism underlying vasodilation whether the $K^+$ channel blockers, charybdotoxin and iberiotoxin directly block the CGRP receptors and that CGRP-evoked relaxation is dependent on the cyclic AMP or $K^+$ channel opening or both actions.

• Journal of Applied Biological Chemistry
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• v.54 no.3
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• pp.206-213
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• 2011

Hepatoprotective effects of Monascus pilosus mycelial ethanol extract (MPME) were examined in high-fat diet induced-obese rats. The rats were randomly divided into 2 groups; normal control (NC) and a high-fat and high cholesterol diet group (HFC). The HFC diet group was fed a 5L79 diet supplemented with 15% lard and 1% cholesterol for 3 weeks for induction of obesity. And then, the rats were divided into 4 groups (n=5); the NC, a HFC diet obesity control group (HF), 0.5% MPME supplemented HFC diet group (MPM), and 2% conjugated linoleic acid (CLA) supplemented HFC diet group for 7 weeks. Whereas the daily weight gain of NC and HFC groups were 3.48 g and 4.48 g, respectively, those of MPM and CLA were 3.09 g and 4.38 g, respectively. Furthermore, activity of serum alanine and aspartic aminotransferase in HF was markedly higher than those of NC group, but, the activity in MPM and CLA was significantly lower than HF. Hepatic reduced glutathione content in MPM and CLA was higher than HF. On the contrary, hepatic lipid peroxide content in MPM and CLA was significantly lower than HF. In conclusion, although the precise mechanisms of the hepatoprotective effects of the MPME in this study are unknown, our study provides experimental evidence that MPME may prevent obesity and hepatic damage by high-fat and high cholesterol diet via inhibition of lipid absorption and induction of reactive oxygen spices scavenging enzyme such as superoxide dismutase.

• Korean Journal of Environmental Biology
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• v.20 no.1
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• pp.73-77
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• 2002

The effect of salicylic acid (SA) on C $d^{2+}$ - induced physiological toxicity in Commelina communis was investigated. 3- weeks old Commelina communis was transferred to and grown in Hoagland solution in the presence or absence of 100 $\mu$M C $d^{2+}$ and SA for 3 weeks. In the treatment of C $d^{2+}$ + SA, the length of stem was increased to 0.7 cm for 3 weeks (C $d^{2+}$, 2.1cm; control, 7.2 cm). C $d^{2+}$ + SA reduced total chlorophyll content up to 86%, and changed chlorophyll a/b ratio below 1.6. C $d^{2+}$ + SA also reduced about 40-78% of water potential, but C $d^{2+}$ increased 16-39% from 1 week to 3 weeks. C $d^{2+}$ + SA also inhibited 27% of Fv/Fm, but in case of C $d^{2+}$, Fv/Fm was not changed. The treatment of C $d^{2+}$ + SA showed about 37-58% inhibition of photosynthetic activity when measured at various light intensity (500-1000 $\mu$mol $m^{-2}$ $s^{-1}$ ). In the case of C $d^{2+}$ treatment, photosynthetic activity was inhibited to 12-15%. Similar effect was found in terms of stomatal conductance. Therefore, it could be concluded that the treatment of C $d^{2+}$ + SA into plant decrease or block various physiological activities and lend to die by double effects of both chemicals.cts of both chemicals..

• Korean Journal of Ecology and Environment
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• v.43 no.1
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• pp.136-141
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• 2010

In situ experiments of Nutrient Enrichment Bioassays (NEBs) were conducted in the field along with in the laboratory to determine which nutrient limited phytoplankton growth as a indicator of primary productivity. For the NEBs, the water was sampled using a polyethylene-lined container and dispensed into 6 L water tank in the laboratory. The control (C, no nutrient spike) and six treatments of phosphorus (P), 2-fold phosphorus (2P), 4-fold phosphorus (4P), nitrate nitrogen ($NO_3$-N), 2-fold nitrate nitrogen ($2NO_3$-N), and phosphorus and nitrate nitrogen (P+$NO_3$-N) were set up in the lacustrine zone near the dam site, Daechung Reservoir in September, 2009 and analyzed the diel changes of total nitrogen (TN), total phosphorus (TP), and chlorophyll-$\alpha$ (Chl-$\alpha$) in the cubitainers. The short-term NEBs showed that algal response in the treatments spiked phosphorus (P, 2P, and 4P) were significantly (p < 0.05) greater than the response in the control (C), and nitrogen-spike. Also, the response in 4P-treatment was greater than those in the P- and 2P-treatments. In contrast, there was no significant differences (p > 0.20) between the $NO_3$-N and $2NO_3$-N treatment. The outcomes of the NEBs suggest that phosphorus limited the phytoplankton growth and nitrogen was not limited in this system. Furthermore, in the N + P treatments, the response was minimum, compared to all other treatments and the control, indicating that even if the system is evidently P-limited system, when added the nitrogen, the response showed the inhibition. Also, > 95% of observed long-term TN:TP ratios in the ambient water showed > 17, which is the criteria of P-limitation, supporting the P-limitation in the system. Overall, these results suggest that phytoplankton biomass near the dam is a direct linear function of P-loading near the watershed, if the phosphorus pool is mainly dissolved fraction.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.138-143
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• 2003

Total methanolic extract of Chrysanthemum coronarium L. var. spatiosum (Compositae) was revealed to have anti-hepatotoxic activity against galactosamine-induced toxicity on primary cultured rat hepatocytes. After successive partitioning with chloroform, n-butanol, and water, the chloroform fraction showed a significant inhibition activity of 51% at 50 ppm, compared with that of silybin, 45.9% at $100\;{\mu}M$. The chloroform fraction was subjected to silica gel column chromatography and yielded active CH-II, CH-V and CH-VI subfractions, and the anti-hepatotoxic activity of these subfractions were 47.6, 56.3, and 23.2%, respectively, at 50 ppm. Total glutathione contents of CH-II, CH-V, and CH-VI increased by 49.8, 43.9, and 47.5% of the control, respectively at 50 ppm, whereas that of silymarin was, 59.7% at $100\;{\mu}M$ after challenged with galactosamine. The ratio of (reduced glutathione) / (total glutathione) in CH-II, CH-V and CH-VI subfraction showed similar values of $0.86{\sim}0.87$ at 50 ppm, whereas that of silymarin was, 0.85 at $100\;{\mu}M$. The incorporation of $[^3H]-uridine$ uptake into RNA was not affected by these active subfractions.

• Tuberculosis and Respiratory Diseases
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• v.50 no.2
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• pp.158-170
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• 2001

Background : Although an oxidants and antioxidants imbalance has been considered in the pathogenesis of chronic obstructive pulmonary disease (COPD), there is a paucity of reports focussing on the smoking-induced changes of oxidants and antioxidants in COPD. Method : The concentration of antioxidants (ascorbic acid, uric acid, retinol, and $\alpha$- & $\gamma$-tocopherol) was measured in the serum and induced sputum of 30 healthy controls and 34 stable COPD patients using high performance liquid chromatography (HPLC). The inhibition of lipid peroxidation as an index of antioxidant capacity was measured in the serum by a TBA assay. Results : The serum concentration of ascorbic acid, $\alpha$-tocopherol, and retinol were significantly lower in the patients with COPD than in healthy controls ($484.8{\pm}473.3$ vs $1497.8{\pm}819.2\;pmol/L$, $48.38{\pm}17.34$ vs $73.96{\pm}26.29\;pmol/L$, p<0.001, and $9.51{\pm}8.33$ vs $15.01{\pm}5.88\;pmol/L$, p<0.05, respectively, mean$\pm$SD). However, there were little differences in the ascorbic acid and uric acid concentrations in the induced sputum between the COPD patients and the controls. The induced sputum to serum ratio of ascorbic acid was significantly higher in COPD patients compared with healthy control (0.375 vs 0.085, p<0.05). In the normal controls, the serum ascorbic acid concentration was lower in smokers than in nonsmokers ($1073{\pm}536$ vs $1757{\pm}845\;pmol/L$, p<0.05), but the level was still higher than that of the COPD patients (p<0.05). The serum retinol levels were correlated with $FEV_1$ in COPD patients (r=0.58, p<0.05). The products of lipid peroxidation were increased in normal smokers and COPD compared with norma1 nonsmokers ($115.56{\pm}19.93$ vs $120.02{\pm}24.56$ vs $91.87{\pm}20.71\;{\mu}mol/{\mu}mol$ Pi of liposome, p<0.05). Conclusion : Cigarette smoking may induce the dep1etion of serum antioxidants and this depletion of antioxidants is suggested to play a role in the pathogenesis of COPD.