• Applied Biological Chemistry
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• v.9
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• pp.149-152
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• 1968

In order to establish a effective application method of compost and phosphorus fertilizer for rice plant, a field experiment has been conducted and the variation of the organic matter content in soils has been observed. The results may be summarized as follows. 1. It was more effective to split the application time into basic and in 2 weeks before the young premodia formation for the yield increase of rice grain than to applicate once basic, and it was apparent that the lesser amount of organic matter during the growing period of rice was consumed, the higher yield of rice grain was resulted. 2. The combined application of compost and phosphorus fertilizer showed a tendency to raise higher the grain yield than the separated application. 3. It was suggested that the split application of compost bring yield increase of rice grain.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.17
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• pp.143-148
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• 1974

Field and pot experiments were conducted for the split application of potash in paddy (Oryza sativa L. cultivar Jinheung.) Production and the experimental results were analysed with regard to the yield of paddy and its yield components. The absence of potash at the reproductive stages such as primodial and heading period but supplied most of the potash at the early growth stages, resulted in an increase of panicles but in a decrease of grain numbers per panicle and yield of paddy. On the other hand, however, the reduced amount of potash application at the earlystage of growth showed a decreased number of panicles and yield of paddy, particulary where lime and fresh rice straw were applied.

• Korean Journal of Agricultural Science
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• v.7 no.1
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• pp.6-11
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• 1980

In order to find the interaction between phosphorus and nitrogen effects during low temperature treatment, experiments of rice planted late at low water temperature were conducted and the following results were obtained. As the application of phosphorus increased, the soluble nitrogen content in the rice plants was decreased, while the degree of ripening was improved, especially when the application of nitrogen increased. When the heading was promoted due to high temperature, degree of ripening was improved. The number of spikelets increased due to the increased application of nitrogen fertilizers, and then The effects of phosphorus application on the improvement of ripening was less apparent.

• Applied Biological Chemistry
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• v.23 no.4
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• pp.246-250
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• 1980

The effects of two Cytozyme complexes, Crop Plus and Seed Plus, applied to rice (variety: Jinheung) were evaluated during the 1980 rice growing season. Primary objectives were directed to determine the effects of rates, timing and method of application of the products on the yield of rice. For the Seed Plus test, seed was soaked in the diluted Seed Plus solution(1 : 100) for 24 hours just prior to sowing. The Crop Plus was diluted to 1 : 12 for seedling treatment. Seedling roots were immersed in the diluted solution for 3 hours before transplanting. Crop Plus spray applied at the rates of 450ml/ha or 900ml/ha when rice plants were in the panicle initiation, heading or tillering stage respectively to compare the effects of rates and timing of application. The weather was not favorable for rice growth during the growing season except the tillering stage. The foliar spray at the tillering stage was more effective than the spray at the panicle initiation, and the rates of 900ml/ha showed better results than 450ml/ha. Combination of seed treatment and foliar spray increased grain yield by 16% over untreated control plots.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.12
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• pp.49-54
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• 1972

In order to learn the growth pattern of high yielding paddy and the effect of slaked lime and potassium on the growth pattern, a relationship between the number of panicles and tillers at different growth stages, as well as the effect of slaked lime and potassium on the increase of tillers were studied with three pot and one field experimental results. 1. The number of tillers at early stages of growth has little or negative correlation with the number of panicles. However. the correlation grows positively as the growth stage proceed and become to highly significant from the stage closing to the panicle formation. 2. Potassium is effective on increasing tillers and calcium on decreasing them. The above contradictory effect of potassium and calcium would practically be an important point for the establishment of high yielding technics of paddy, which be the one to be studied from the view point of plant physiology and soil chemistry. 3. The negative effect of calcium on tillering also seemed to be attributed to the pH rise of the media.

• Applied Biological Chemistry
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• v.25 no.4
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• pp.232-238
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• 1982

From ^{15}N$ labelled nitrogen experiments on 13 fields use efficiency by difference method was higher than that by labelling method in 80% of fields tested indicating augmentation of soil nitrogen uptake by fertilizer nitrogen. Both methods showed very similar trend among fields. Sulfur coated urea(SCU) and point application increased fertilization efficiency(yield increment per fertilizer nitrogen applied, Fe) to 23 from 15 of split application through the increase of fertilizer use efficiency from 29(Eu) to 50 but tended to decrease efficiency of absorbed fertilizer nitrogen(yield increment per nitrogen derived from fertilizer, Ef) from 50. to 46 High yielding capacity of Tongil line appears to be attributed to the higher Ef, translocation efficiency and soil nitrogen preference index(soil nitrogen increment in plant per the increment of fertilizer nitrogen in plant, PI). This studies confirmed that yield under fertilizer application system depends on Fe which is the multiplication of Eu and Ef and that the improvement of fertilizer management(form, application method and time) increases principally Eu, the limit of which is controlled by Ef that is attributed mainly to varietal characteristics.

• Journal of Animal Environmental Science
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• v.8 no.3
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• pp.135-144
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• 2002

A computer simulation was carried out to investigate the optimum capacity of liquid manure tank spreader which is used as a tractor attachment. Soil physical properties, such as soil moisture content, bulk density, soil hardness and soil types were measured in the 10 major rice production area for computer simulation. Mathematical model which include soil physical properties and vehicle factor was used for computer simulation. Most of the soil type of the investigated area was sandy clay loam. Soil moisture content ranged between 30 and 40% mostly. Soil bulk density was in the range of 1,500 to 1,700 kg/$m^3$. Soil hardness ranged between 1 to 18 $cm^2$. Soil hardness incorporate the effects of many soil physical properties such as soil moisture content, soil type and soil bulk density, and so the range of soil hardness is greater than any other physical properties. The capacity of liquid manure tank spreader was above 3,000 kg$_{f}$ for the most of the investigated areas, and mostly in the range of 4,000 to 6,000 $kg_f$ depending upon the slip. But for the soft soil area such as Andong and Asan, the tractor itself has mobility problem and shows no pulling force for some places. For this area, the capacity of liquid manure tank spreader ranged between 1,000 and 2,000 $kg_f$ mostly, so the capacity of liquid manure tank spreader should be designed as a small capacity trailer compared to the other area.mpared to the other area.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.22 no.2
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• pp.32-36
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• 1977

Experiments were conducted to know the effects of seed bed temperatures on the sprouting of seeds and seedling growth in the phytotron and field. Sprouting of seeds were most uniform when seed bed was stored under the straw and vinyl mulching for 48 hours after seed bed temperature increased up to 3$0^{\circ}C$ by the sun. In the phytotron, optimum temperature was 32$^{\circ}C$ for sprouting and day/night temperature of 25/30 and 20/15$^{\circ}C$ for greening and hardening of seedlings, respectively. In the field, the best results were obtained under the conditions of sprouting in the seedling chamber heated by electricity and greening the hardening under the double vinyl tunnel in the upland nusery bed.

• Korean Journal of Organic Agriculture
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• v.26 no.3
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• pp.489-500
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• 2018

Rural Development Administration (RDA) is promoting the AFACI IPM (Asian Food & Agricultural Cooperation Initiative program). AFACI consist of 12 countries including Bangladesh, Cambodia, Thailand, Vietnam and so on. The main goal of the AFACI IPM project is 'Establishment of an international cooperative network for the best management of migratory rice planthoppers and setting data-base of pests occurrence information. As a result of the suvey, Planthoppers were increasing all the way from tillering stage to ripe stage and do not appear to be peak of one or two like korea case. In detail, 1,673 of BPH (Nilaparvata lugens) occurred in survey site of Svay Reang, Cambodia, followed by 1.237 at Dobila, Bangladesh. In the case of White backed planthopper (Sogatella furcifera), 1,163 of WBPH occurred in survey site of Dobila, Bangladesh and 849 WBPH were collected at Hamkuria, Bangladesh. It is expected to verify the occurrence and movement patterns of hoppers among member countries in the future.

• Korean Journal of Environmental Agriculture
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• v.2 no.1
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• pp.1-5
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• 1983

A study was undertaken to investigate the persistence of diazinon in two different soils under field conditions. Half-life of diazinon granule(5%) incorporated into soils at a rate of 0.15 ㎏ a.i./l0a was 11 and $9{\sim}12$ days in Suweon and Iri soil under field conditions, respectively. Diazinon residues in brown rice and rice straw harvested from Suweon field were also evaluated by scheduled application intervals. On the basis of maximum residue limit of diazinon in brown rice, it is recommended that the insecticide could be applied upto 15 days before harvest at the limit of 4 spraying times.