• Title/Summary/Keyword: Phosphate

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Determination of optimum fertilizer rates for barley reflecting the effect of soil and climate on the response to NPK fertilizers (기상(氣象) 및 토양조건(土壤條件)으로 본 대맥(大麥)의 NPK 시비적량결정(施肥適量決定))

  • Park, Nae Joung;Lee, Chun Soo;Ryu, In Soo;Park, Chun Sur
    • Korean Journal of Soil Science and Fertilizer
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    • v.7 no.3
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    • pp.177-184
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    • 1974
  • An attempt was made to determine simple and the most reasonable fertilizer recommendation for barley utilizing the present knowledge about the effect of soil and climatic factors on barley response to NPK fertilizer in Korea and establishing the critical contents of available nutrients in soils. The results were summarized as follows. 1. The relationships between relative yields or fertilizers rates for maximum yields from quadratic response curves and contents of organic matter, available $P_2O_5$, exchangeable K in soils were examined. The trend was more prospective with relative yields because of smaller variation than with fertilizer rates. 2. Since the relationship between N relative yields and organic matter contents in soils was almost linear over the practical range, it was difficult to determine the critical content for nitrogen response by quadrant methods. However, 2.6%, country average of organic matter content in upland soils was recommended as the critical point. 3. There showed a trend that average optimum nitrogen rater was higher in heavy texture soils, colder regions. 4. The critical $P_2O_5$ contents in soil were 96 or 118 ppm in two different years, which were very close to the country average, 114 ppm of $P_2O_5$ contents in upland soils. The critical K content in soil was 0.32 me/100g, which was exactly coincident to the country average of exchangeable K in upland soils. 5. According to the contents of avaiiable $P_2O_5$ and exchangeable K, several ranges were established for the purpose of convenience in fertilizer recommendation, that is, very low, Low, Medium, High and very High. 6. More phosphate was recommended in the northern region, clayey soils, and paddy soils, whereas less in the southern region and sandy soils. More potash was recommended in the northern region and sandy soils, whereas less in the southern region and clayey soils. 7. The lower the PH, the more fertilizers were recommended. However, liming was considered to be more effective than increas in amount of fertilizers.

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The Protective Effects of Ethanol Extract of Wild Simulated Ginseng on Carbon Tetrachloride Induced Acute Hepatic Injury in Mouse (사염화탄소 유발 급성 간독성 생쥐모델에서 산양삼 에탄올 추출물의 간 보호 효과)

  • Lee, Soo-Min;Park, Sun-Young;Jang, Gi-Seuk;Ly, Sun-Yung
    • Journal of Nutrition and Health
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    • v.41 no.8
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    • pp.701-710
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    • 2008
  • The wild simulated ginseng (WSG) has been effectively used in folk medicine as a remedy against hepatic disease, hypertension and arthritic disease. However, there is still lack of scientific proof about its antioxidant capability. The present study has been conducted to evaluate the protective role of the WSG ethanol extract in the CCl4-induced oxidative stress and resultant hepatic disfunction in ICR mice. The electron donating abilities and IC50 of WSG etnanol extract were 76.86 ${\pm}$ 1.06% and 33.3 ${\mu}g$/mL (that of ascobic acid was 16.5 ${\mu}g$/mL), respectively. Total antioxidant status of WSG extract was 2.13 ${\pm}$ 0.06 mmoL/mg, while the values of ascorbic acid and BHT were 3.63 ${\pm}$ 0.06 and 3.12 ${\pm}$ 0.02, respectively. ICR mice (aged 3weeks) were fed for 4 weeks on AIN-93M diet and had free access to food and water. The animals were divided into three groups: normal group (intraperitoneally (i.p) injected with PBS at 100 ${\mu}L$/mouse), group C; CCl4-induced and without any treatment. (i.p injected only PBS, 100 ${\mu}L$ /mice), group G; CCl4-induced and treated with WSG (i.p injected with 5 mg WSG extract per mouse, suspended in 100 ${\mu}L$ phosphate buffer). After the i.p. injection of WSG or PBS (5 times for 7weeks), all mice were administered CCl4 in olive oil at the last day of the experiment, except for normal group. The normal group was administered only olive oil. Determination of plasma triglyceride, total cholersterol, fasting glucose and GPT activity was performed using automatic blood analyzer. To evaluate the protective effect against the oxidative stress, DNA fragmentation and TBARS were determined in blood leucocytes and RBC and hepatocyte, respectively. Body and organs weights and food intake did not show significant differences among the groups. Blood total cholesterol of group G was similar to that of normal group, which was the lowest in group C. The fasting blood glucose level was the highest in normal group (205.20 ${\pm}$ 135.24), which were decreased in group C (134.2 ${\pm}$ 79.31) and group G (126.48 ${\pm}$ 77.05). TBARS values in a red blood cell and hepatic tisuue homogenate were lower in group G comparing to the group C. DNA% in tail, tail length (TL) and tail moment (TM) of blood leucoocytes showed the highest values in group C (20.11 ${\pm}$ 2.47, 17.36 ${\pm}$ 2.58, 94.11 ${\pm}$ 12.29) and they were significantly diminished in group G (9.63 ${\pm}$ 1.19, 7.04 ${\pm}$ 1.50, 38.64 ${\pm}$ 7.60). In conclusion, wild simulated ginseng might be a protective agent against the oxidative stress.

Variation in Cartenoid Pigment and lipids of the Arkshell, (Anadara broughtonii) according to the Environmental Factors of the Growing Area (서식환경요인에 따른 피조개육의 Carotenoid색소와 지질성분의 변화)

  • Ha, Bong-Senk;Kang, Dong-Soo;Kim, Yung-Gwan;Kim, Kui-Shik
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.18 no.1
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    • pp.71-92
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    • 1989
  • The seasonal variations of environmental sea water, arid carotenoid and lipid composition of reddish muscle tissue of arkshell, Anadara broughtonii in Chungmu and $Y{\check{o}}su-area$ were investigated. In the sea water, pH value, salinity, electrical conductivity of Chungmu and $Y{\check{o}}su-area$ were similar tendency, but water temperature in annual average at Chungmu-area was about $2^{\circ}C$ higher than that of $Y{\check{o}}su-area$. The concentration of nitrite-nitrogen, ammonia-nitrogen, phosphate-phosphours at Chungmu-area were slightly higher than those at $Y{\check{o}}su-area$. Meanwhile the concentration of silicate-silicious at $Y{\check{o}}su-area$ was about 2 times higher than that of Chungmu-area. The bacterial density of the sea water was ranged from 3.6 to 93/100ml for coliform and 3.0 to 15/100ml for fecal colifrom at Chungmu-area, but the coliform was ranged 7.3 to 150/100ml and the fecal coliform was ranged 3.6 to 20/100ml at $Y{\check{o}}su-area$. Among the coliform, 8.9% Escherichia coli, 33.9% Citrobacter freundii, 41.1% Enterobacter aerogenes groups were classified and 16.1% was not identified. In the hemoglobin content of reddish muscle tissue of arkshell, one from Chungmu-area was ranged from 1.1 to 2.5 g /dl and one from $Y{\check{o}}su-area$ was ranged from 1.7 to 4.4 g /dl. In total carotenoid content, 0.80 to 1.28mg/100 g muscle was in Chungmu-area and 0.45 to 0.99mg/100 g muscle was in $Y{\check{o}}su-area$. Among the carotenoid compositions, pectenolone content was 63.0% in annual average from Chungmu area and 59.6% from $Y{\check{o}}su-area$, 6.5% from Chungmu area and 18.9% from $Y{\check{o}}su-area$ in ${\beta}-carotene$, 9.9% from Chungmu-area and 9.1% from Yosu-area in pectenoxanthin, 11.2% from Chungmu-area and 5.2% from $Y{\check{o}}su-area$ in diatoxanthin monoester were observed. In the seasonal variation for the major carotenoids, the content of pectenolone was continuously incresedbefore spawning period and showed the maximum in July, but decresed after spawning period. Diatoxanthin monoester was gradually incresed during all growing period from March to next January. And ${\beta}-carotene$ was decresed before spawning period and showed the maximum in July but incresed after spawning period. The major fatty acids of total lipid and fractionated lipid classes from total lipid namely neutral-, glyco- and phospholipid were $C_{16:0},\;C_{18:1},\;C_{22:6},\;C_{20:2},\;C_{18:2},\;C_{20:5}\;and\;C_{18:3}$ acid in the muscle tissue of arkshell. The content of neutral lipid showed about 2 times higher than polar lipid in the muscle tissue of arkshell from both Chungmu and, $Y{\check{o}}su-area$. The content of total and neutral lipid was decresed during spawning period. In the seasonal variation for fatty acid compositions, the content of polyenenoic acid in total and neutral lipid was decresed and saturated acid was incresed. On contrary, polyenoic acid in glyco and phospholipid was incresed and saturated acid was decresed during spawning period from July to September. The sterol composition in total lipid were mainly consisted of cholesterol, campesterol, brassicasterol and ${\beta}-sitosterol$. Especially, the rate of content in cholesterol showed decrese during spawning period butcampesterol showed increse from March to November.

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Nature of Suppressiveness and Conduciveness of Some plant pathogens in Soils (토양내(土壤內) 식물(植物) 병원균(病原菌)의 발병억제(發病抑制) 및 유발성질(誘發性質))

  • Shim, Jae-Ouk;Lee, Min-Woong
    • The Korean Journal of Mycology
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    • v.18 no.3
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    • pp.164-177
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    • 1990
  • This study was carried out to obtain some useful data for increasing an effective ginseng production. There was a direct relationship (r=0.2645) between spore germination of Fusarium solani and soil pH, and (r=0.315) between Cylindrocarpon destructans and soil pH. On the other hand, there was a direct relationship (r=0.19) between relative hyphal growth of Rhizoctonia solani and soil pH. There was a direct relationship (r=0.21) between number of total bacteria and F. solani, (r=0.37) between actinomycetes and F. solani and (r=0.20) between celluloytic bacteria and F. solani. However, there was an inverse relationship (r=-0.20) between number of total fungi and F. solani. There was a direct relationship (r=0.24) between number of actinomycetes and R. solani. Each ginseng pathogen-suppressive soil screened was 40 in F. solani, 20 in C. destructans and 9 soil samples in R. solani among 146 soil samples, respectively. The mean contents of K, Ca and Mg were fairly lower in each ginseng pathogen-suppressive soil than conducive soil, whereas Na were somewhat lower. The mean contents of organic matter were over 2 times higher in each ginseng pathogen-suppressive soil than conducive soil. The mean contents of phosphate were fairly lower in F. solani and R. solani-suppressive soil than conducive soil and, on the other hand, were somewhat higher in C. destructans-suppressive soil than conducive soil. The mean soil pH was somewhat lower in each ginseng pathogen-suppressive soil than conducive soil. The mean contents of sand were about 2 times higher in each ginseng pathogen­suppressive soil than conducive soil, whereas silt and clay were somewhat lower. The microbial numbers of total bacteria, total fungi and celluloytic fungi were higher in F. solani-suppressive soil than conducive soil, whereas actinomycetes and celluloytic bacteria were lower. Each microbial number of total bacteria or total fungi indicated a significant difference (p=0.05) between F. solani­suppressive and conducive soil, and the microbial number of actinomycetes was a highly significant difference (p=0.01) between F. solani-suppressive and conducive soil. The microbial numbers of total bacteria, total fungi, actinomycetes and celluloytic fungi were higher in C. destructans-suppressive soil than conducive soil, whereas celluloytic bacteria were about 2 times lower. On the other hand, the microbial numbers of total fungi were higher in R. solani-suppressive soil than conducive soil, whereas total bacteria, actinomycetes, celluloytic bacteria and celluloytic fungi were lower. Fourteen of 16 F. solani-suppressive soils tested were suppressive to ginseng root rot, whereas fifteen of 16 C. destructans-suppressive soils were suppressive. Ginseng root rots of ginseng disease-suppressive soils were in the range of 1.0-17.4% in F. solani-suppressive soil and 0.2-20.4% in C. destructans-suppressive soil, respectively.

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Effects of High Glucose and Advanced Glycosylation Endproducts(AGE) on the in vitro Permeability Model (당과 후기당화합물의 생체 외 사구체여과율 모델에 대한 역할)

  • Lee Jun-Ho;Ha Tae-Sun
    • Childhood Kidney Diseases
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    • v.10 no.1
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    • pp.8-17
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    • 2006
  • Purpose : We describe the changes of rat glomerular epithelial cells when exposed to high levels of glucose and advanced glycosylation endproducts(AGE) in the in vitro diabetic condition. We expect morphological alteration of glomerular epithelial cells and permeability changes experimentally and we may correlate the results with a mechanism of proteinuria in DM. Methods : We made 0.2 M glucose-6-phsphate solution mixed with PBS(pH 7.4) containing 50 mg/mL BSA and pretense inhibitor for preparation of AGE. As control, we used BSA. We manufactured and symbolized five culture dishes as follows; B5 - normal glucose(5 mM) + BSA, B30 - high glucose(30 mM) + BSA, A5 - normal glucose(5 mM) + AGE, A30 - high glucose(30 mM) + AGE, A/B 25 - normal glucose(5 mM) + 25 mM of mannitol(osmotic control). After the incubation period of both two days and seven days, we measured the amount of heparan sulfate proteoglycan(HSPG) in each dish by ELISA and compared them with the B5 dish at 2nd and 7th incubation days. We observed the morphological changes of epithelial cells in each culture dish using scanning electron microscopy(SEM). We tried the permeability assay of glomerular epithelial cells using cellulose semi-permeable membrane measuring the amount of filtered BSA through the apical chamber for 2 hours by sandwich ELISA. Results : On the 2nd incubation day, there was no significant difference in the amount of HSPG between the 5 culture dishes. But on the 7th incubation day, the amount of HSPG increased by 10% compared with the B5 dish on the 2nd day except the A30 dish(P<0.05). Compared with the B5 dish on the 7th day the amount of HSPG in A30 and B30 dish decreased to 77.8% and 95.3% of baseline, respectively(P>0.05). In the osmotic control group (A/B 25) no significant correlation was observed. On the SEM, we could see the separated intercellular junction and fused microvilli of glomerular epithelial cells in the culture dishes where AGE was added. The permeability of BSA increased by 19% only in the A30 dish on the 7th day compared with B5 dish on the 7th day in the permeability assay(P<0.05). Conclusion: We observed not only the role of a high level of glucose and AGE in decreasing the production of HSPG of glomerular epithelial cells in vitro, but also their additive effect. However, the role of AGE is greater than that of glucose. These results seems to correlate with the defects in charge selective barrier. Morphological changes of the disruption of intercellular junction and fused microvilli of glomerular epithelial cells seem to correlate with the defects in size-selective barrier. Therefore, we can explain the increased permeability of glomerular epithelial units in the in vitro diabetic condition.

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Soil properties in Panax ginseng nursury by parent rock (모암별 인삼묘포지의 토양특성에 관한 연구)

  • Min, Ell-Sik;Park, Gwan-Soo;Song, Suck-Hwan;Lee, Sam-Woong
    • Korean Journal of Agricultural Science
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    • v.30 no.1
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    • pp.31-40
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    • 2003
  • A research has been done for growing characteristics of Korean ginseng in Geumsan of Chungnam Province. It had been made to determine the transitional element concentrations of the rocks, divided by biotitic granite(GR) and phyllite(PH). The physical and chemical properties of their weathering soils and ginseng nursery soils were analyzed. The texture in the GR weathering and ginseng nursery soils were sandy clay, and the texture of the PH weathering and ginseng nursery soils were heavy or silty clay. The bulk densities of the GR and PH weathering soils were $1.21{\sim}1.32g/cm^3$ and $1.26{\sim}1.38g/cm^3$, respectively. Also, the bulk densities of the GR and PH ginseng nursery soils were $1.02{\sim}1.10g/cm^3$, respectively. The pH (4.80) of the GR weathering soil were lower than the pH of the PH(5.34) weathering soil. The pH in the 2 year and 4 year-ginseng nursery soil of the GR were 4.39 and 4.40. In addition, those of the PH were 5.24 and 5.34, respectively. The difference in pH of the two nursery soils could be from the pH difference between the two parent materials. The organic matter contents of the GR weathering soils(0.24%) were higher than those of the PH(1.02%) weathering soils. The organic matter of the 2 and 4 year-ginseng GR nursery soils were 0.87% and 1.52%, and of the PH nursery soils were 2.06% and 2.96%, respectively. The total nitrogen contents of the GR weathering soils were 259.43ppm and of the PH weathering soils were 657.22ppm. Those of 2 and 4 year-ginseng GR nursery soils were 588.04ppm and 657.22ppm and those of the PH nursery soils were 1037.72ppm and 1227.96ppm, respectively. The nitrate and ammonium contents of the GR weathering soils were the extremely small, and those of the PH weathering soils were 6.7ppm and 9.94ppm. Those of 2 year-ginseng GR nursery soils(223.09ppm and 26.96ppm) were higher than those of PH(19.46ppm and 8.23ppm) nursery soils. And those of 2 year-ginseng PH nursery soils(14.22ppm and 16.84ppm) were lower than those of PH(306.93ppm, 34.21ppm) nursery soils. The difference was due to fertilizer types and more deposits of nitrate after oxidation of ammonium. The phosphate contents of the GR and PH weathering soils were 14.41ppm and 38.60ppm. Those of GR 2 and 4 year-ginseng nursery soils were 46.89ppm and 102.44ppm and those of the PH nursery soils were 147.04ppm and 38.60ppm. The cation exchange capacities of the GR weathering soils were 12.34me/100g and those of the PH weathering soils were 15.40me/100g. Those of 2 and 4 year-ginseng GR nursery soils were 15.80me/100g and 7.70me/100g and those of PH nursery soils were 12.14me/100g and 12.83me/100g. All of exchangeable cation($K^+$, $Ca^{2+}$, $Mg^{2+}$, $Na^+$) contents in the nursery soils were higher than those in the weathering soils. The $SO_4{^2-}$ contents of the weathering soils in both of the GR(5.98ppm) and PH(9.94ppm) were higher than those of the GR and PH ginseng nursery soils. The $Cl^-$) contents of the GR and PH weathering soils were a very small and those of the nursery soils(2-yr GR: 39.06ppm, 4-yr GR: 273.43ppm, 2-yr PH: 66.41ppm, 4-yr PH: 406.24ppm) were high because of fertilizer inputs.

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Studies on Direct Sowing-Dry Paddy Rice Culture in the Middle Part of Korea (중부지방에 있어서의 수도건답직파재배 기술체계확립에 관한 시험연구)

  • Jai-Hyoun Lee
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.7 no.1
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    • pp.1-29
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    • 1969
  • Experiments on rice concerning it s varieties, fertilization, seedling dates and herbicides have been conducted to determine the most desirable method of direct sowing cultivation on dry paddy field land in the middle part of Korea. The results obtained at the Office of Rural Development of Choongnam Province are as follows:. 1. Sixteen different derivatives from the main varieties of low land rice were cultivated on a dry paddy field by the direct sowing method; at the same time, a few varieties were tried adopting the common transplanting cultivation method. The yield and yield factors from these two groups were examined to give the following results: a) Compared to the common transplanting cultivation, the direct sowing method showed remarkably increased number of panicles while the number of flowers per panicle was shown to be significantly decreased. The maturing ratio was detected to be lowered. The yield horn them differed according to the different varieties : good yield was obtained from Hokwang while Norin #25 proved poor when compared with the common transplanting cultivation method. b) Among sixteen varieties tested, Sunsou, Norin #25, Jaigou, Hokwang, Palkueng and Gosi showed comparatively high yields, their yield being more than 325 kilograms per 10 Are, but Nampoong, Paldal, Nongkwang, Norin #29, Eunbangju #101 and Shiro gane showed less yield, their yield being less than 271 kilograms per 10 Are, the relations between the yield and the yield factors can be summarized as follows; Number of varieties and their rice yield. 1) The varieties which were great in the, number of panicles and high in yield=Jaigoun, Hokwang Palkueng and Gosi. 2) The varieties which were low in the number of panicles and high in yield=Sounsou and Norin #25. 3) The varieties which were great in the number of panicles and poor in yield=Eunbangju #101 and Sirogane. 4) The varieties which were poor in the number of panicles and poor in yield: Nampung, Paldal and Norin #29. Number of flowers per panicle and yield. 1) The varieties which were great in the number of flowers per panicle and high in yield: Sounsou, Norin #25 and Gosi. 2) The varieties which were poor in the number of flowers per panicle and high in yield ; Jaigoun, Hokwang and Palkueng. 3) The varieties which were great in the number of flowers per panicle and poor in yield: Paldal and Nampung. 4) The varieties which were poor in the number of flowers per panicle and poor in yield: Norin #29. Eunbangju #101 and Sirogane. Maturing ratio and yield. 1) The varieties which were high in the maturing ratio and high in yield: Jaigoun, Sounsou, Norin #25 and Palkueng. 2) The varieties which were low in the maturing ratio and high in yield: Hokwang and Gosi. 3) The varieties which were early maturing rat io and low in yield: Hokwang and Gosi. 4) The varieties which were late maturing ratio and poor in yield: Eunbangju #101, Nampungand Sirogane 1, 000 grain weight and yield. 1) The varieties which were heavy in 1, 000 grains weight and high in yield=Norin #25 and Hokwang. 2) The varieties which were light in 1, 000 grains weight and high in yield=Sounsou and Jaigoun. 3) The varieties which were heavy in 1, 000 grains weight and poor in yield=Nongkwang and Eunbanju. 4) The varieties which were light in 1, 000 grains weight and poor in yield=Norin #29 and Sirogane. 2. The experiment on fertilization showed that the most desirable amount to be given per 10 Are was 10 kilograms of Nitrogen, 5 kilograms of phosphate and 6 kilograms of potassium; and when the Nitrogen given exceeded 8 kilograms, its effect was better when given in amsll consecutive (split) amounts, while the maturing ratio and the number of the flowers per panicle increased when Nitrogen was given in large amount during the later stage of growth of rice. 3. The experiment on the date and amount of seedling showed that the tested variety, Sunsou gave the best results when planted on the days between 25 April and 10 May. Eight liters per 10 Are were preferable if planted early and 12 liters per 10 Are if planted late. The reason why the later planting gave a lower yield was that the number of flowers per panicle was fewer. 4. The experiment on the irrigation for rice with direct sowing cultivation immersed in water showed that it was the most satisfactory when irrigated on 25th June, 55 days after its seedling, its plot giving the best yield. The plots 10th June and 15th July showed just as good results. However, irrigated later, than 15th July it showed lower yields. 5. Compared to the yield of the plot controlled by the common method, the yield from the plots treated with chemical herbicide such as LOROX, TOK, PCP, SWEP, Mo-338 on dry condition soil seemed poorer, but significant difference was not found statistically. On the other hand in the case where chemical herbicides such as TOK, Mo-338, Stam F-34 or ORDRAM were used after irrigation, the yield from the ORDRAM and TOK treated plots did not show significant differences compared to the common hand weed controling method, but those treated with chemicals other than the above showed a lower yield.

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Situation of Fertilizer Industry in Korea (비료산업(肥料産業)의 현황(現況)과 문제점(問題点))

  • Lee, Yun Hwan
    • Korean Journal of Soil Science and Fertilizer
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    • v.15 no.1
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    • pp.34-48
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    • 1982
  • 1. Production and consumption of chemical fertilizers in Korea could be divided into five different phases of total imports, setting up fertilizer plants, self-sufficiency in production, net export, and diversification in compound fertilizers. Currently the nation has production capacity of 800 thousand M/T of nitrogen, 400 thousand M/T of phosphate ($P_2O_5$) and 200 thousand M/T of potash ($K_2O$). 2. Yearly consumption increased every year, since 1964, 28,000 M/T N, 7,700 M/T $P_2O_5$, and 7,500 M/T $K_2O$ until 1972, when the increase jumped by eight times for $P_2O_5$ and seven times for $K_2O$ for the following 3 years in anticipation of their short supply. Now total consumption has been more or less stabilized at the level of 450 thousand M/T N, 220 thousand M/T $P_2O_5$ and 180 thousand M/T $K_2O$ for the last 7 years. 3. Current operation rate of fertilizer plants is around 80% throughout the whole industry, after going through several different levels depending on demand at times. 4. Fertilizer export started in 1967 and reached a peak of 150 thousand nutrient ton in 1972, about 20% of total production, before temporarily stopping due to over-demand for next three years. The export resumed again in 1976 rise to the all time high of 670 thousand nutrient ton in 1980, almost half of total production, and then started to decline due to higher price of petroleum since then. 5. The decline in fertilizer export appears to be accelerated because several countries, in South-Eastern Asia, traditional export market for Korean fertilizers, started to build their own plants, since 1980, based on their raw materials of especially petroleum. 6. Current consumption in Korea is about 30 nutrient Kg per 10a, equivalent to that in Western European countries, partly due to new high-yielding rice varieties and extensive cultivation of fruit trees and vegetables. Additional fertilizer demand in future can be anticipated in reclaimed land for growing grass and forestry.

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Study on the Salt Tolerance of Rice and Other Crops in Reclaimed Soil Areas. -6. On the Effects of Increased N. P. K. Applications for Rice Plant in Reclaimed Salty Areas (간척지(干拓地)에서 수도(水稻) 및 기타작물(其他作物)의 내염성(耐鹽性)에 관(關)한 연구(硏究) -6. 염분간척지(鹽分干拓地)에서 수도(水稻)에 대한 N, P, K,의 증비효과에 관(關)하여)

  • Im, H.B.
    • Korean Journal of Soil Science and Fertilizer
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    • v.3 no.1
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    • pp.35-41
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    • 1970
  • The experiment was conducted at the salt concentration of 0.5% and 1% end of April, respectively, in low and high-salty and the non-salty areas of silt loam with the Nongkwang, rice variety. The factorial design with confounding blocks of 3 levels each of 10, 15 and 20 kg of N, 8, 12 and 16kg of phosphate and potash, respectively, per 10a was applied. 1. N applications increased by 1.5 and 2 times with the fixed amount of $P_2O_5$ and $K_2O$ (8kg/10a each) increased the proportion absorbed to the applications of N in both non salty and low-salty areas. It was observed that the absorption of Ca and Si was inhibited by either an increased treatment of N alone or combination with the other nutrients in the salty area. 2. In the non-salty area, an increased applications of standard amount of N, $P_2O_5$ and $K_2O$ respectively did not increased the yields. Doubling the application of $K_2O$ resulted in a decreased yield. 3. Applications of additional of 1.5 and 2 times the 10 kg of N per 10a increased the rice yields 12% and 21% respectively, in the low-salty area. An increased application of $P_2O_5$ and $K_2O$ failed to bring about an increased yield. 4. Increasing the application of N gave a significant increased in the yield of rice grain and 1.5 times of N applications were seemed profitable on the high-salty area. Although an increased applications $P_2O_5$ and $K_2O$ seemed to increase the yields of grain, no significant increase was observed. 5. An increased application of N increased the number of panicles up to 1.5 times the standard amount in the non-salty area, but no further increase resulted by doubling the application. The number of panicles was increased in proportion to the increased application of N in both low and high-salty areas. An increased application of $P_2O_5$ increase the number of panicles per unit area in each experimental plot while that of $K_2O$ had no effect but rather decreased the number. 6. The effect of an increased application of N decreased the weight of panicle in the non-salty area, but when the application was increased to 1.5 times or more an increased weight of panicle resulted in both salty areas. Doubling the application had approximately the same effect as 1.5 times the application. Increasing the applications of $P_2O_5$ and $K_2O$ had no effect on the panicle weight in the experimental plots. Increasing the applications of N, $P_2O_5$ and $K_2O$ did not effect the weight of 1,000 grains produced in the non-salty and salty areas. Increasing the application of N decreased the number of grains per panicle in the non-salty area but increased the number of grains per panicle in either salty areas. 7. The ratio of matured grains was highest in the low-salty area and the lowest in the high-salty area. An increased N applications decreased the ratio of matured grains in the non-salty area. No effect was observed in both low and high-salty areas. Increased the $P_2O_5$ and $K_2O$ application showed no effect on the ratio of matured grains in the experimental plots. 8. Increased applications of N, $P_2O_5$ and $K_2O$ was observed not to change the percentage of milling recovery in any experimental plots. Broken rice was increased equally by an increased application of N in the non-salty and salty areas but more remarkably so in the former. 9. Increased applications of N increased the straw production equally in the non-salty, low and high-salty areas. However, no increased production was observed from heavier applications of $P_2O_5$ and $K_2O$. Additional N applications reduced the rate of rough grain weight v.s. straw weight in the non-salty area but increased the ratios in both low and high-salty areas. Additional $P_2O_5$ and $K_2O$ had no effect with the ratio.

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Physico-Chemical Properties of Aggregate By-Products as Artificial Soil Materials (골재 부산물의 용토재 활용을 위한 특성 분석)

  • Yang, Su-Chan;Jung, Yeong-Sang;Kim, Dong-Wook;Shim, Gyu-Seop
    • Korean Journal of Soil Science and Fertilizer
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    • v.40 no.5
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    • pp.418-428
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    • 2007
  • Physical and chemical properties of the aggregate by-products including sludge and crushed dust samples collected from the 21 private companies throughout the country were analyzed to evaluate possible usage of the by-products as artificial soil materials for plantation. The pH of the materials ranged from 8.0 to 11.0. The organic matter content was $2.85g\;kg^{-1}$, and the total nitrogen content and available phosphate content were low as 0.7 percents and $12.98mg\;kg^{-1}$, respectively. Exchangeable $Ca^{2+}$, $Mg^{2+}$, $K^+$, and $Na^+$ were 2.29, 0.47, 0.02 and $0.05cmol\;kg^{-1}$, respectively. Heavy metal contents were lower than the limits regulated by environmental law of Korea. Textural analysis showed that most of the materials were silt loam with low water holding capacity ranged from 0.67 to 7.41 percents, and with low hydraulic conductivity ranged from 0.4 to $2.8m\;s^{-1}$. Mineralogical analysis showed that the aggregate by product materials were mostly composed of silicate, alumina and ferric oxides except calcium oxide dominant materials derived from limestones. The primary minerals were quartz, feldspars and dolomites derived from granite and granitic gneiss materials. Some samples derived from limestone material showed calcite and graphite together with the above minerals. According to the result, it can be concluded that the materials could be used as the artificial soil material for plantation after proper improvement of the physico-chemical properties and fertility.