• Journal of Bio-Environment Control
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• v.20 no.1
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• pp.33-39
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• 2011

This experiment was carried out to understand the characteristics of inorganic ion uptake of strawberries to establish a labor saving, environmentally sound closed hydroponic system. Nitrate nitrogen is absorbed in the perlite and granule rockwood with the almost same rate and in the cocopeat with a little bit higher concentration. At the early growth stage, phosphate was absorbed in comparatively high rate, but it is gradually declining to $4me{\cdot}L^{-1}$ in the three treatments except for reused medium. Four treatments showed different absorption rates for potassium, respectively, however, it became $3{\sim}5me{\cdot}L^{-1}$ gradually. But there was few sign to absorb potassium in the reused medium. High concentration of calcium was absorbed in the cocopeat medium and the lowest absorption rate in the granule rockwool, and it turned out to be $2{\sim}3me{\cdot}L^{-1}$ absorption concentration rate in the perlite. All three treatments showed $1me{\cdot}L^{-1}$ at the average absorption concentration rate of magnesium. Iron showed high absorption rate but it showed steadily 1~2 ppm absorption rate. Results of this experiment will be utilized for developing the new substrates for strawberry closed hydroponic system.

• Korean Journal of Soil Science and Fertilizer
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• v.9 no.2
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• pp.71-76
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• 1976

Field experiments were conducted to study the effect of amendments such as lime and organic matter for mulberry trees on the newly reclaimed sandy loam soil for three years. The results are summarized as follows. 1. Compared to the N.P.K check plot with treatments, leaf yield was increased by 20 to 80%. Leaf yield was higher in the order of NPK+magnesia lime < NPK+compost > NK+fused phosphate NPK+green manure > NPK+barley straw> NPKplot. 2. Mulberry leaf yield showed high significant positive correlation with total weight and volume of root, length and number of wattles and the content of CaO or MgO in leaf respectively. 3. It is known that dead part sympom of top branch during cold season is associated with unbalance magnesium to potassium in mulberry leaf. It is estimated that such symptom was deminished when the ratio of $K_2O/MgO$ in leaf becomes 6.0 or higher. 4. In establishing a mulberry field on hilly reclaimed soil, application of magnesium and calcium with compost was essential but higher amount of potassium fertilizer should be followed in order to prevent dead part symptom of top branch of mulberry trees.

• Journal of Nutrition and Health
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• v.6 no.3
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• pp.37-45
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• 1973

The main character of the Korean diet has been found to be low in protein both quantity and quality and high in carbohydrate. The purpose of this survey was to study the amount of salt intake related to the dietary pattern in Korea. The nutrition survey was conducted in a mountainous farming area located in Auhchun-ri, Gaebuk-myon, Changsoo-gun, Chunbuk Province, February 14-19 in 1973 (7 days). The precise weighing method was used in evaluating the kinds of foods and nutrients intake for 24 households during a three day period. The physical examinations were performed by a doctor on 120 persons and a detailed biochemical test on both blood and urine was made on 42 persons over 40 years old. The results obtained are summarized as follows: (1) Average nutrients intake of an adult per day: calorie intake was 2,446 Cal and its components-protein(61.1g) was 10 percent, fat(12.9g) was 5 percent and carbohydrate(521g) contributed 85 percent of the total calories. Other nutrients-calcium (443mg), thiamine(1.09mg), riboflavin (0.90mg), niacin (14.4mg) and vitamin C (63.2mg) were lower than the recommended daily allowance but vitamin A(2,083 I.U.), iron(11mg) and phosphorous(998mg) were slightly higher than that. (2) To evaluate the nutritional deficiences, clinical examinations were conducted. Angular stomatitis was present in 16.7 percent of those examiners. No edema was found. The rate of osteoarthritis, hepatomegaly diseases appeared in 20 percent of the total subjects and the symptoms appeared highest among those Iron 50 to 59 years old. (3) The following chemical components of blood serum were analyzed and found to be within the normal range: glucose, blood urea nitrogen, uric acid, total protein, albumin, globulin, bilirubin, total cholesterol, inorganic phosphate, alkaline phosphatase, sodium, potassium, chloride, calcium and lecithine dehydrase. One case of each of the following were found: hyperglycemia, hypocholesterolemia, renal problem, hypoproteinaemia and diabetes mellitus, and two persons were classified as showing hypoglycemia and hyponaturemia. (4) The sodium content in urine was 199.6 mEq/L, potassium content was 24.6 mEq/L. The sugar, pH and specific gravity in the urine was shown to be normal.

• Horticultural Science & Technology
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• v.33 no.4
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• pp.492-500
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• 2015

Our previous report demonstrated successful isolation of soil-borne bacteria that suppressed the potential of Rhizoctonia solani AG2-2 (IV) causing turfgrass large patch disease when applied to Korean lawngrass (Zoysia japonica). The current study aimed to uncover the mechanisms of this antagonism of Rhizoctonia solani and to define culture conditions for the isolated microbes. We found that two Bacillus isolates, I-009 and FRIN-001-1 strains, produced cellulase and siderophore, but not chitinase, while the Pseudomonas YPIN-022 strain was found to release only siderophore, implying that three antagonistic bacteria commonly interrupt Fe uptake by the large patch pathogen. The I-009 and FRIN-001-1 isolates grew best at 35 and $30^{\circ}C$ in growth medium of pH 5 to 8 for 32 and 28 h, respectively, while optimum growth for the YPIN-022 strain was found at $35^{\circ}C$ at pH 5 to 9 for 24 h. Good growth of I-009 and YPIN-022 over 24 h was obtained in M9 minimal medium supplemented with 1% sucrose, 0.5% yeast extract and 0.1% potassium chloride. FRIN-001-1 grew well in M9 medium with 1% mannitol, 0.5% yeast extract and 0.1% potassium phosphate dibasic.

• Journal of Sericultural and Entomological Science
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• v.23 no.2
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• pp.50-54
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• 1982

This investigation was conducted to know the present conditions of the the chemical components in the soils and chemical fertilizer rates applied in the Yuyu village located Sanne myun, Buan gun, Jeonbug province. Total silkworm rearing farms in this village were 54 and 47 of them were chosen at random. Average fertilizer rate applied in this village was 40.8-13.7-13.9kg/10a as N-P$_2$O$\_$5/-K$_2$O. Farmers seemed to stress too much to nitrogen fertilizer. Available P$_2$O$\_$5/ in soils was below 7ppm (by Bray No. 1 method). However, 47% of the farms applied phosphate fertilizer less than 11kg/10a. The average of exchangeable K in soils was 0.68me/100g. Nine of the farms applied potassium fertilizer more than 20kg/10a and 7 farms of them had the soils contained above 0.4me/100g as the potassium content. The average soil pH was 5.3. All of the soils were below than pH 6.5. Exchangeable Ca and Mg were 3.62 and 0.83me/100g, respectively. The average lime requirement was 269kg/10a. The average organic matter content was 2.55% and for 72% of the total farms, organic matter content was below than 3%.

• Journal of Nutrition and Health
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• v.41 no.6
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• pp.539-549
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• 2008

This study was conducted to examine food and nutrient intakes of weekday and weekend with 329 high school boys residing in Seoul using the 3-day food record. Frequency for breakfast skipping was the highest as compared with lunch and dinner skipping. Frequencies for breakfast and lunch skipping were significantly higher in weekend than weekday (p<0.05). The daily average food, vegetable food and animal food intakes were 1,327.6 g, 800.5 g, and 425.8 g, respectively. Total food and vegetable food intakes of weekday were significantly higher than weekend(p<0.05). The dietary variety score(DVS) was 20.5 in daily average, 23.3 in weekday and 15.1 in weekend, which showed significantly higher in weekday than weekend(p<0.05). The daily averages of energy, protein, fat and carbohydrate intake were 2244.9 kcal, 89 g, 72.6 g, and 311.2 g, respectively. Fat intake was significantly lower and carbohydrate, fiber, phosphate, iron, sodium, potassium, vitamin A, niacin, folate, and vitamin C intakes were significantly higher in weekday than weekend (p<0.05). The percentages of energy intake from carbohydrate, protein, and fat were 55.4%, 15.8%, 28.8% in daily average, 56.8%, 15.8%, 27.4% in weekday and 53.6%, 15.8%, 30.7% in weekend, respectively. The percentages of energy intake from carbohydrate in weekday and weekend were below 60%, and that from fat was above 27% in weekday and weekend. Carbohydrate intake was significantly higher and fat intake was significantly lower in weekday than weekend(p<0.05). Energy intakes of daily average, weekday and weekend were above 83% as compared with estimated energy requirement(EER). Intakes of dietary fiber, calcium, potassium, vitamin C, riboflavin and folate were below 75% as compared with adequate intake(AI) or recommended intake(RI). Mean adequacy ratios(MAR), an index of overall dietary quality were 0.78 in daily average, 0.80 in weekday and 0.75 in weekend. MAR of weekend showed significantly lower than weekday(p<0.05). This study revealed that the overall nutrient intake status was worse in weekend than weekday among high school boys.

• Korean Journal of Food Science and Technology
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• v.23 no.2
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• pp.188-191
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• 1991

A study was carried out to investigate the control effect of sodium and potassium phosphates, sodium citrate and three different salts mixtures on kimchi fermentation when they were added into half-fermented kimchi in the concentration range of $0.001{\sim}0.01\;M$. The salts mixtures added were sodium phosphates mixture(CA-A), addition of $NaNO_2$, Ca-EDTA and BHA to CA-A(CA-B) and substitution of BHA with sodium citrate in CA-B. The results showed that sodium phosphates and sodium citrate significantly inhibited the kimchi fermentation while potassium phosphate had little effect. The order of control effect was $Na_3PO_4-Na_2HPO_4-sodium\;citrate-NaH_2PO_4-K_2HPO_4-KH_2PO_4$. Among the salts mixtures, CA-A showed the most reducing effect in the fermentation rate followed by CA-C and CA-A. The mixture of CA-C could extend the time of holding pH $4.2{\sim}4.4$ by approximately 6 times at $4{\sim}25^{\circ}C$ when it was compared to control. The microbial growth study of total and Leuconostoc mesenteroides also showed a very significant decrease in their numbers.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.3
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• pp.223-228
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• 2013

The calcium-activated $K^+$ ($BK_{Ca}$) channel is one of the potassium-selective ion channels that are present in the nervous and vascular systems. $Ca^{2+}$ is the main regulator of $BK_{Ca}$ channel activation. The $BK_{Ca}$ channel contains two high affinity $Ca^{2+}$ binding sites, namely, regulators of $K^+$ conductance, RCK1 and the $Ca^{2+}$ bowl. Lysophosphatidic acid (LPA, 1-radyl-2-hydroxy-sn-glycero-3-phosphate) is one of the neurolipids. LPA affects diverse cellular functions on many cell types through G protein-coupled LPA receptor subtypes. The activation of LPA receptors induces transient elevation of intracellular $Ca^{2+}$ levels through diverse G proteins such as $G{\alpha}_{q/11}$, $G{\alpha}_i$, $G{\alpha}_{12/13}$, and $G{\alpha}s$ and the related signal transduction pathway. In the present study, we examined LPA effects on $BK_{Ca}$ channel activity expressed in Xenopus oocytes, which are known to endogenously express the LPA receptor. Treatment with LPA induced a large outward current in a reversible and concentration-dependent manner. However, repeated treatment with LPA induced a rapid desensitization, and the LPA receptor antagonist Ki16425 blocked LPA action. LPA-mediated $BK_{Ca}$ channel activation was also attenuated by the PLC inhibitor U-73122, $IP_3$ inhibitor 2-APB, $Ca^{2+}$ chelator BAPTA, or PKC inhibitor calphostin. In addition, mutations in RCK1 and RCK2 also attenuated LPA-mediated $BK_{Ca}$ channel activation. The present study indicates that LPA-mediated activation of the $BK_{Ca}$ channel is achieved through the PLC, $IP_3$, $Ca^{2+}$, and PKC pathway and that LPA-mediated activation of the $BK_{Ca}$ channel could be one of the biological effects of LPA in the nervous and vascular systems.

• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.327-335
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• 2012

Nutrient uptake of each part of grapevine in the new grapevine cultivars (Jinok, Hongisul) was analyzed for making standard of annual fertilizations at four years. One year grown diploid cultivar 'Jinok' was showed more vigorous growth of root than other cultivar. Annually total nutrient of grapevine was absorbed with the same ratio of three major nutrients (Nitrogen, Phosphate, and Potassium). However about 30% of total absorbed nutrient of 3~4 year grown grapevine was distributed bunches. Potassium was measured as major nutrient in the bunch, accumulated in the peel and flesh (about 1% of D.W.). Magnesium was mainly accumulated in the petiole (about 1% of D.W.). Calcium has accumulated in the leaf (about 0.95% of D.W.), that concentration in this part was similar concentration of nitrogen (about 1.25% of D.W.). Nutrient requirement of four year grown 'Jinok' (N; 55.5 g, P; 7.7 g, K; 42.0 g, Ca; 34.6 g, Mg; 11.1 g) required less fertilizers than 'Campbell Early' (N; 57.4 g, P; 7.9 g, K; 44.4 g, Ca; 37.3 g, Mg; 12.2 g) needed. 'Hongisul' required less fertilizers compared to other grapevine cultivars, but cultural practice system for production of grape should be develop to improve their poor bud burst and fruit set.

• Korean Journal of Soil Science and Fertilizer
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• v.13 no.4
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• pp.99-105
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• 1981

To find the relationship between the adequate amount of soil chemical components and ginseng growth including root weight, 49 farmer's red ginseng field from the main ginseng growing area were studied intensively. 1. The ranges of soil chemical component of high yield ginseng field were 8.9 to 14.5 me/100g of CEC 1.5 to 3.5% of organic matter, 45 to 257 ppm of available phosphorus, 0.34 to 0.55 me/100g of potassium and 0.002 to 0.012 of K/P ratio respectively. 2. Higher content of organic matter, CEC, exchangeable potassium and higher rate of K/P were observed in soils of ginseng field with high yield than in soils of low one. The CEC content in soil was positively correlated with the plant growth, and available phosphate content in soil was negatively correlated with yield of ginseng root. 3. There was highly positive significant correlation between root yield of ginseng and K/P ratio of ginseng soil. Similar result also observed between root yield of ginseng and K/P ratio of upper part of ginseng plant.