• Korean Journal of Soil Science and Fertilizer
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• v.7 no.2
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• pp.113-118
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• 1974

A study was carried out to investigate the effect of application time of fertilizer nitrogen on its rate of uptake and its distribution in rice plant. The rate of applied fertilizer was 100kg/ha, as a single application at transplanting time and four equal split applications of 25kg/ha was applied at transplanting time, 3 weeks after transplanting, 1 week before the primodial initiation stage of growth and at the flag leaf stage of growth, respectively. The ammonium sulfate was labelled with N-15, as 1% atom excess for single application and 4.4% atom excess for split applications. The results are sumarized as follows: 1. The effect of split application of nitrogen on yield was observed. The yield of brown rice of the single application at transplanting time was 3.1 ton/ha and the split application was 3.4 ton/ha. However, without nitrogen the yield was reduced to 1.9 ton/ha. 2. The number of grains per panicle and 1000 grains weight were increased as split application of nitrogen, but for the number of panicles per hill and maturing rate, the single application of nitrogen revealed favorable results. 3. The rate of uptake of applied fertilizer nitrogen showed a tendency that the efficiency of fertilizer nitrogen increased by top dressing. The rate of uptake of applied nitrogen as basal application, first top dressing, second top dressing and third top dressing was 28%, 33% 51% and 63%, respectively. 4. After shooting stage of the growth, nitrogen in straws transfered to grains. The nitrogen applied at flag leaf stage was absorbed by root and easily accumulated in grains rather than straw.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.1
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• pp.70-75
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• 2010

In Korea, standard N application level was amended from 110 to 90kg per ha for high quality rice production in 2005. So far, N application method, however, has not been considered for yield and quality based on changed standard N application level. Therefore, this experiment was conducted to find out more efficient N application method for improving rice quality or labor saving under the amended standard N application level with several varieties at three site (Suwon, Iksan, and Milyang) for two years from 2005 to 2006. Top dressing of N at 15 days before heading compared to the standard (25 days before heading) showed improved rice qualities such as 1000 grain weight and head rice ratio without changing rice yield and protein content of brown rice. In addition, there were no significant differences in yield and quality between different N split application of 70-0-30% and 50-30-20%, indicating that the former would be useful for labor saving without yield decrease and quality deterioration.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.6
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• pp.460-464
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• 2007

This study was carried out to elucidate the proper split application method of nitrogen fertilizer for early dry seeding culture of rice in Honam plain area from 1997 to 1998 in Korea. Dongjinbyeo was selected as rice variety for this experiment. The rate of $160kg\;ha^{-1}$ of nitrogen was split as 40-30-30% of total nitrogen at three different application time combination ; T1) basal-5th leaf-panicle formation(PF) stage, T2) 3rd leaf-5th leaf-PF, and T3) 3rd leaf-7th leaf-PF. The content of $NH_4-N$ in soil at 5th leaf stage was higher in top dressing plots(T2, T3) compared with basal application(T1), at 7th leaf stage it was most in top dressed at 3rd leaf and 5th leaf stage, but there was no difference at heading stage. Amount of nitrogen uptake and nitrogen use efficiency was higher in the order of T3, T2 and T1(basal application). Spikelet number per unit area was more in the order of T3, T2 and T1, but rate of ripened grain and 1,000 grain weight were not significantly different among three nitrogen split application methods. Milled rice yields were higher in top dressed plots compared with basal nitrogen application plots. From the results of this experiment, reasonable nitrogen split application method for early dry seeding culture of rice could be 40-30-30% of total nitrogen at 3rd leaf, 7th leaf and panicle formation stage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.21 no.2
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• pp.269-276
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• 1976

This experiment was conducted to find out how to increase efficiency of fertilizer nitrogen and how to change the weed population with different methods of nitrogen application. Mudball deep placement, at 10-12cm soil depth, produced significantly the highest grain yield within the application methods with same amount of nitrogen (60kg N/ha). It produced also same grain yield with conventional application methods, timely split application method, with 90kg N/ha. Basal application of nitrogen increased weed population and it showed higher dry weight of weed than top dressing methods at early growth stage of rice.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.5
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• pp.405-412
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• 1992

Growth characters of dry seeded paddy rice was studied at different levels of nitrogen(N) split application (basal : immediately after irrigation : 2 weeks after irrigation: 25 days before heading: heading stage with 10 : 20 : 30 : 20 : 20%, 20 : 30 : 20 : 20 : 10%, 30 : 40 : 0 : 20 : 10%, and 100% basal of slow release urea) in tillage and no-tillage systems. On May 17 in 1990, 6kg /10a of dry seeds of a breeding line of Milyang 95 was broadcasted and covered with a power tiller. Between tillage and no-tillage systems yield and its components, lodging related characteristics, and contents of cellulose, hemicellulose and lignin of culm base were similar. Leaf area index at heading stage was higher in tillage, but lodging index was lower compared with those in no-tillage plot. Culm length, effective tiller ratio, culm base weight, 1000-grain weight, harvest index in slow release N applied plot were higher compared with those in other N treatments. Grain yield of rice among levels of N split applications was similar in tillage, but it was higher in slow release N applied plot in no-tillage if 1kg /10a of additional N was applied as urea at panicle formation stage. At early growth stage N concentration and N uptake were lower in the slow release N applied plot, but higher after heading stage compared with other N treatments. The number of tillers was lowest in slow release N applied plot during the tillering stage, but the number of panicles per hill was similar to other N treatments.

• Archives of Plastic Surgery
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• v.42 no.3
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• pp.341-345
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• 2015

Background A tie-over dressing is the accepted method to secure skin grafts in order to prevent haematoma or seroma formation. We describe the novel application of a barbed suture tie-over for skin graft dressing. The barbs act as anchors in the skin so constant tensioning of the suture is not required. Methods From January 2014 to August 2014 we used the technique in 30 patients with skin defects requiring split-thickness or full-thickness grafts. Patient demographics, clinicopathological details and graft outcome were collected prospectively. Results The majority of cases were carried out for split-thickness skin grafts (n=19) used on the lower limb (n=20). The results of this novel technique were excellent with complete (100%) graft take in all patients. Conclusions Our results demonstrate the clinical application of a barbed device for securing skin grafts with excellent results. We find the technique quick to perform and the barbed device easy to handle, which can be applied without the need for an assistant.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.1
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• pp.1-13
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• 2006

Response of grain yield and milled-rice protein content to nitrogen topdress (N) timing at panicle initiation stage (PIS) is critical for quantifying real-time N requirement for target grain yield and milled-rice protein content. Two split-split-plot experiments with three replications, one in 2004 and the other in 2005, were conducted in Experimental Farm, Seoul National University, Suwon, Korea. The experiments included three N rates at tillering stage (TS), three N timing treatments at panicle initiation stage (PIS) and two rice cultivars. The N rates at TS, N timing at PIS, and rice cultivars were randomly assigned to main plot, sub plot, and sub-sub plot, respectively. Results showed that the delayed N application at PIS reduced grain yield in 2004 and increased milled-rice protein content in both years significantly at 0.05 probability level. The calculated optimum N timing at PIS from pooled data by N rates and rice cultivars in two years was at 28 days before heading (DBH). However, real-time of N timing at PIS was dependent on plant growth and N status around PIS that in turn was dependent on applied N rates at TS. The optimum N timing at PIS was at 30 DBH for no N treatments at TS while at 27 DBH for 3.6 and 7.2 kg N/10a treatments and at 27 and 29 DBH for Hwaseongbyeo and Daeanbyeo, respectively. In general, earlier applied N at PIS resulted in lower milled-rice protein content but the highest grain yield was expected to be obtained when N topdress at PIS was applied at the time when shoot N concentration started to drop below about 23 mg/g due to dilution effect after transplanting. In conclusion, the results of our experiments imply that the currently recommended N topdress time (24DBH) at PIS in Korea should be reconsidered for the higher grain yield and the better quality of rice.

• Korean Journal of Environmental Agriculture
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• v.20 no.4
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• pp.218-224
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• 2001

To find out the optimum level of slow release N fertilizers (MS 10, MS S10, LCU 80, and LCU 100), total amount of nitrogen required throughout the growing season were applied in the seedling box or incorporated into paddy soil. Four levels of the slow release N fertilizers (0, 6, 9 and 12 kg N/10 a) were mixed with commercial rice nursery bed soil. N release rate and electrical conductivity(EC) of the slow release fertilizers were greater in the order of MS 10 > LCU 80 ${\fallingdotseq}$ LCU 100 > MS S10 and higher as temperature increased. No seedlings were emerged in all MS 10 plots. The seedling emergence rate of LCU 80 and LCU 100 decreased as the N level increased and seedlings were wilted severely on the 13th day after sowing at 9 and 12 kg N/10 a. In MS S10 plots the emergence rate was higher than 80% at all N levels and seedling growth was normal until 30 days after sowing. Yield of rice was similar between seedling box application and soil incorporation in paddy of MS S10. Yield of rice among the 6, 9, 12 kg N/10 a of MS S10 and conventional 12 kg N/10 a of urea split application was similar, but it was significantly higher compared with no N plot. Fertilizer N recovery of MS S10 decreased as fertilizer level increased and it was significantly higher compared with conventional urea split application.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.3
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• pp.264-269
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• 1996

Four leavels of nitrogen and five split-application method were investigated in the puddled drill seeding of rice in tidal land paddy field of Munpo series in Gyehwado. Soil ammonium concentration increased of higer nitrogen level, and was higher in latex coated urea(LCU) than urea split-application, and stage of $NH_4-N$ was the higher in maximum tillering stage. Rice yield, nitrogen availability and yield increment rate according to nitrogen levels were the highest when nitrogen was applied 200kg/ha and also it were the highest in the LCU application by 30% decreased than urea application as affected by application method. Adequate application amount of nitrogen was estimated 222kg/ha in direct drill seeding of rice in tidal land paddy field.

• Korean Journal of Medicinal Crop Science
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• v.8 no.1
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• pp.69-73
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• 2000

To investigate proper method of nitrogen application, six levels of nitrogen fertilizer and five different split applications were tested in Liriope platyphylla. Leaf length and content of total nitrogen in plant increased with the increase of nitrogen application level from zero to 360kg per ha. Number and weight of tuber increased with the increase of nitrogen level and tuber production reached to highest level of 4.44M/T per ha with the level of 220kg nitrogen. And then, tuber production decreased with the addition of extra nitrogen fertilizer to level of 360kg per ha. In the research of proper nitrogen split application, tuber yield (3.52M/T per ha) was increased by 18% at the combination of 40% basal application and three times of top dressing, than that of 100% basal application.