• Journal of the Korea Organic Resources Recycling Association
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• v.29 no.2
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• pp.15-23
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• 2021

This study was conducted to evaluate the field application of the developed recommendation system in organic rice (Oriza sativa L.) paddy and to investigate the mineral nitrogen content in soil and rice productivity. According to the developed system, hairy vetch (HV), rye+rapeseed oil cake (R+OC), rapeseed oil cake (OC) for only basal fertilization (OC-B), OC for split application (OC-S), pig manure compost (PMC), and chemical fertilizer (CHM) were applied to paddy soil at the rate of 107~133 kg N/ha. Results were followed, unhulled rice yield of OC-S (111%), OC-B (110), R+OC (106), HV (101), and PMC (96) were no significantly different with CHM (100). Also there was positive correlation (R²=0.803^*) between unhulled rice yield and cumulative inorganic N in soil. For nitrogen use efficiency of rice, OC-B, OC-S, and R+OC were not significantly different with CHM. In conclusions, the developed organic materials use recommendation system was effective for organic rice productivity. It could be useful for organic farmer to apply the organic materials use recommendation system for rice.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.6
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• pp.731-737
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• 1995

This experiment was carried out at National Crop Experiment Station in 1994 to obtain basic information of growth characters and yield of rice under various nitrogen split application methods on different soil textures in direct seeding on dry paddy. Hwaseongbyeo sown on April 27 by flat drill seeding, and irrigation was done at 3 leaf stage after seedling establishment. Number of seedling stand was 159~177 seedlings per $m^2$ regardless of soil texture and nitrogen application method. Number of panicle per unit area in loam was higher than in sandy loam, and it also was higher in top dressing plots, which were 3 times application at rate of 40-30-30% (3rd leaf stage -7th leaf stage -panicle initiation stage) and 4 times application 10-30-30-30%(basal-3rd leaf stage -7th leaf stage -panicle initiation stage), than in conventional method. Leaf colour, leaf area index and dry matter production at heading stage were highest at top dressing plots among the nitrogen application methods in both sandy loam and loam. Lodging index in top dressing plots increased by low breaking weight with long culm. There were field lodging of degree 3 in top dressing plots. Rice yield in sandy loam, loam increased by 7~9%, 6~9% in top dressing of nitrogen, respectively.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.11a
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• pp.236-237
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• 2005

An experimental study on the Hybrid Cooling Tower has been done having a rated capacity of 3RT. Counter flow type fill, cross flow type fill and hybrid-type fill which is combined with two type fills as previously stated having a height of 0.3m have been used in the 0.8m${\times}$0.4m${\times}$1.9m dimensional tower respectively. The heat exchanger is consisting of 2 or 3 rows. The relevant temperatures and the velocities were selected based on the typical Korean weather for the year round operation of the tower. The cooling capacity of the tower is explained with respect to varying air inlet velocities, wet-bulb temperatures, and air to cooling water volume flow rate ratio (L/G ratio). The capacity of the hybrid-type fill was much superior to other fills, but hybrid-type fill shows higher pressure drop.

• Korean Journal of Soil Science and Fertilizer
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• v.1 no.1
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• pp.13-26
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• 1968

To establish the most efficient method of nitrogen and phosphorus fertilization in paddy rice a series of internationally coordinated research using $N^{15}\;P^{32}$ isotopes were carried out from the year 1962 through 1967, supervised by the Joint FAO/IAEA Division of Atomic Energy in Agriculture under the auspicies of FAO, UN. In Korea College of Agriculture, Seoul National University had been participated in the Coordinated Research Programme from the year 1963 through the last year, arid the results obtained through the six years' researches are summarized as follows: 1. In the application of superphosphate broadcasting or placement at the surface of paddy as basal dressing was most efficient. 2. Split or late application of superphosphate did not affect the grain yield of the rice, but its efficiency in the rice plant uptake was less than in the case of basal dressing of whole amounts. 3. The contents of available soil phoshorus of the experimental sites in Korea were above 60 ppm, and the efficiency of phosphorus utilization of the rice from the fertilizer was approximately 10 per cent. The grain yield response of the rice to phosphorus application in Korea was rather small comparing to those of other countries. 4. The nitrogen uptake of the rice plants from the fertilizer was most efficient when the fertilizer was applied at the time of ear prime growth. However, the most efficient utilization of nitrogen did not necessarily accompany the maximum yield of the rice and basic application of adequate amount of nitrogen was required to secure proper number of panicles. 5. In the application of nitrogenous fertilizer shallow placement at 5 cm depth was most efficient. The effect of split application of nitrogen was not so noticeable. It seemed due to the fact that total application amount of nitrogen, 60 kg N/ha, was smaller than that of usual dosage in Korea. 6. The efficiency of nitrogen utilization of the rice from the fertilizer was about 40 percent in Korea, and the yield reponse of the rice plant to nitrogen application was remarkable comparing to those of other countries, showing the marked differences in the fertilizer efficiency and grain yield according to the application method. 7. The nitrogen uptake of the rice plant was not likely affected by the time and the rate of phosphorus application whereas the efficiency of phosphorus utilization was affected to some degree by the method of nitrogen application.

• Korean Journal of Soil Science and Fertilizer
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• v.12 no.3
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• pp.141-151
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• 1979

To investigate the relationship between the effect of potassium basal and top dressing amount on rice plant under the limed condition, a pot experiment was conducted with Milyang 21, rice variety. Growing status, yield components and chemical component of rice, plant were determined and soils were analyzed along with the growing stages and obtained results are as follows. 1. Control treatment, without lime application shows a good vegetative growth as compared with lime treated one. However grain yield was higher in lime treated pot when potassium was applied as basal and top dressing. 2. There was no big difference between potassium applied and control treatment on growing status of nice plant until 20 days after transplanting. However in case of lime treated pot big difference were observed 20 days after transplanting resulting lower grain yield as compared with control treatment. This trend were severe in a lime treated treatment. 3. In control treatment, potassium basal dressing shows higher grain yield as increase the amount of basal dressing and the highest yield obtained in all basal potassium application treatment. However in case of lime treated pot when two-third of potassium were applied as basal dressing, potassium content of rice became lower at reproductive stage and resulted lower yield. When we applied all the potassium as a basal dressing, there were no differences as compared with control treatment in terms of grain yield. 4. The soil condition that affects potassium absorption disorder in rice plant such as unlimed condition, potassium application should be done as a basal dressing. However in limed condition that potassium absorption disorder occurs scarcely, and potassium content exists unsufficient amount in soil, large amount of potassium as basal dressing and the rest as top dressing are recommended. 5. The higher content of potassium in rice plant at the reproductive growing stage results heavier tillers as compared with lower one so that heavier tillers produce more grain yield. 6. At vigorous growing stage there was a positive correlation between electric conductivity of soil and amount of potasium absorbed by rice plant. This fact suggests that to obtain higher yield large amount of potassium top dressing at late of vegetative growing stage are necessary so that the content of potassium in rice plant will increase and results higher yield.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.499-506
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• 2014

This research was conducted to develop root media containing ground and aged pine bark (GAPB) and ground and raw pine bark (GRPB). After analysis of physico chemical properties, the pine barks were blended with peat moss (PM) or coir dust (CD) in various ratios to formulate 12 root media. Then, two out of 12 root media were chosen based on the physical properties for further experiments. The pre-planting nutrient charge fertilizers (PNCF) were incorporated into two root media and chemical properties were analysed again. The total porosity (TP), container capacity (CC), and air-filled porosity (AFP) of GAPB were 78.7%. 39.4%, and 38.3%, respectively, while those of GRPB were 74.7%, 41.2%, and 33.4%, respectively. The percentage of easily available water (EAW, from CC to 4.90 kPa tension) and buffering water (BW, 4.91-9.81 kPa tension) in GAPB were 12.7% and 8.5%, respectively, which were a little lower than the 13.5% and 8.8% in GRPB. The pH and EC were not different significantly, but cation exchange capacity was different between the two pine barks (GAPB: pH 5.26, EC $0.61dS{\cdot}m^{-1}$, CEC $15.7meq{\cdot}100g^{-1}$; GRPB: pH 5.19, EC $0.32dS{\cdot}m^{-1}$, CEC $9.32meq{\cdot}100g^{-1}$). The concentrations of exchangeable cations in GAPB were Ca 0.32, K 0.05, Mg 0.27 and $0.12cmol+{\cdot}kg^{-1}$, whereas those in GRPB were Ca 0.28, K 0.08, Mg 0.25 and $0.09cmol+{\cdot}kg^{-1}$. The concentrations of $PO_4$-P, $NH_4$-N and $NO_3$-N were 485.8, 0.62 and $0.91mg{\cdot}L^{-1}$ in GAPB and 578, 1.00 and $0.82mg{\cdot}L^{-1}$ in GRPB, respectively, when those were analyzed in the solution of the saturated paste. The TP, CC and AFP in the two selected media were 89.3 and 76.3, and 13.0% in PM+GAPB (8:2, v/v) and 88.2, 68.2 and 20.0% in CD+GRPB (8:2), respectively. The pHs and ECs were 3.8 and $0.24dS{\cdot}m^{-1}$ in PM+GAPB which were a little lower than 5.8 and $0.65dS{\cdot}m^{-1}$ in CD+GRPB. However, the pHs analysed before and after incorporation of PNCF in the two root media did not show large differences. This is because the solubility of dolomitic lime is very low, and the pH it is expected to rise gradually when crops are cultivated int he root media. The information obtained in this study should facilitate effective formulation of root media containing pine bark.

• Korean Journal of Agricultural Science
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• v.38 no.1
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• pp.17-23
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• 2011

This research was conducted to investigate the influence of application rate of liming fertilizers on changes in soil chemical properties and growth of 'Red Madness' petunia in plug production. To achieve this, dolomite (DO) with 0, 1.0, 3.5, 8.0 or 13.0 $g{\cdot}L^{-1}$ and calcium carbonate (CC) with 0, 2.0, 2.5, 3.0, 3.5, or 4.0 $g{\cdot}L^{-1}$ were incorporated into peatmoss + vermiculite (1:1, v/v) during the root substrates formulation. The treatments of 3.5 $g{\cdot}L^{-1}$ of DO and 2.5 or 3.0 $gL^{-1}$ of CC had acceptable ranges of pH and EC in soil solution such as 5.6~6.2 and 0.7~1.0 $dS{\cdot}m^{-1}$, respectively. The faster rising of pH was observed in root media containing CC rather than those of DO. This indicates that the solubility of CC is higher than DO. The soil Ca concentrations in all treatments of CC were 1.8 times as high as those of DO. The treatments of 3.5 or 8.0 $g{\cdot}L^{-1}$ of DO had the highest soil Mg concentrations, but all treatments of CC had lower soil Mg concentrations than control treatment indicating that additional application of Mg fertilizers are required. The elevated application rate of DO or CC resulted in the increase of fresh and dry weight. But plant heights were not influenced by application of liming fertilizers. The results of tissue analysis showed that application of DO or CC influenced the $PO_4{^-}P$, Ca and Mg contents, but not influenced the contents of other nutrients such as N, P, Fe, Mn, Zn and Cu.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.1
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• pp.89-93
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• 1985

In order to develop the nutrient material for growing plants, tobacco leaf debris (T.L.D) that is a residual product of cigarette processing was carbonated at about 50% of its weight and neutralized its alkalinity by nitric and phosphoric acid. This material ($T.L.D+3N-HNO_3+1N-H_3PO_4$ (10:1:1), as a consequence, contained 4.1% of nitrogen, 2.1% of phosphte, and 6.6% of potassium in value of about pH 7. It was very effective on seedling growth to apply 1 Kg of nutrient material per 110 1 of bed soil as basic dressing because of containing not only quick-acting nitrate but also slow-releasing organo-nitrogen and sufficient potassium.

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.3
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• pp.199-203
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• 1990

Effect of a trial compound fertilizer for raising rice seedling in tray, was tested on varieties of Chucheongbyeo and Taebekbyeo and on soil media pH of 6.4 and 5.4. The trial product increased dry weight, number of leaves, and ratio of dry weight to plant height and decreased damping-off incidence. The soil media pH of 6.4. applied trial product, maintained pH 4.0 to 5.4 for seedling period, but the soil media pH of 5.4 was too lower. The nitrogen uptake by rice seedling in the trial product plot was lower at 15 days after seeding compared to the control of straight fertilizer application, but it was higher and 35 days after seeding, resulting in optimum rice seedlings.

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.2
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• pp.128-134
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• 1990

Croping pattern, fertilizer application, Soil chemical characteristics, plant nutritional condition and growth status were investigated in three major vinyl house farms near Yesan. Croping pattern changed from tomato to pumpkin due to tomato diseases such as wilting and blossom-end rot. Wilting seemed to be closely related with high EC, nitrogen and root cyst nematodes. Calcium deficiency seemed to be due to high potassium, EC in soil and high uptake of iron. Chinese cabbages in summer showed poor growth (80% inhibition) due to high EC(1.8mmho/cm) and easily got wenny root disease that might due to high phosphorus (1055ppm) in soil. Summer radish showed poor growth (50% inhibition) due to high EC(1.6mmho/cm), K and Mg resulting in base imbalance. Farmers used 5 kinds of compound fertilizer as basal application and one without P for top dressing. Urea and KCL were used for top dressing. Heavy application of livestock manure and chemical fertilizer for every crop made eutrophic even in subsoil.