• Korean Journal of Soil Science and Fertilizer
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• v.27 no.2
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• pp.85-91
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• 1994

An attempt to adjust the standard levels of NPK fertilizers application was made with the analytical data of soil and the results of field experiments on 18 vegetable crops 1. There was a remarkable accumulation of available $P_2O_5$ and exchangeable K of soil in the periods of 1980~1990 comparing with 1960~1970. 2. New fertilizer recommendations based on the accumulation of soil components enabled to decrease fertilizer requirements of major vegetable crops. It was founded that if such new recommendations were adopted by the farmer, 0~6.0kg N/10a, 0.7~12.3kg $P_2O_5/10a$ and 2.0~9.0kg $K_2O/10a$ could be saved without affecting the yield of crops 3. The formulas of fertilizer application for crops were corrected in order to determine optimal rate of each farmer field according to chemical properties of soil.

• Korean Journal of Soil Science and Fertilizer
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• v.26 no.1
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• pp.25-30
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• 1993

It is common that in the vegetable cultivation areas, the farmers tend to continue the heavy fertilization to maximize the crop yields in short term. This results in the accumulation of fertilizer elements in the soil and increase in the electrical conductivity of soil. Disregarding these, farmers continue to apply heavy doses of fertilizers. A field experiment was conducted to find out on such a soil whether fertilizer application taking the quantity of nutrients accumulated in the soil into account would save the fertilizer without losing the yield of crop, using Chinese cabbage and spinach as test crops. The findings of the experiment is summarized as following. 1. The yield of Chinese cabbage was not affected by reduction of $19kg\;P_2O_5/10a$ and $7kg\;K_2O/10a$ as compared to farmers doses, and in case of spinach the yield rather was increased under the reduction of $22kg\;P_2O_5/10a$ and $22kg\;K_2O/10a$. 2. The reduction of fertilizers according to plant nutrient status of soils did not affect the inorganic nutrient contents of the crops significantly, in both Chinese cabbage and spinach. 3. A trend was observed that the reduction in the P and K fertilizers application would shorten the storage period of Chinese cabbage. 4. The reduction in P and K fertilizers application resulted in the reduction in available P, exchangeable K, EC and $NO_3-N$ in the soil after the harvest of the crops.

• Korean Journal of Soil Science and Fertilizer
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• v.9 no.1
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• pp.39-45
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• 1976

The content of nitrogen, phosphorus, potassium, calcium and magnesium of hulled barley grown on farmer's field with various N.P.K rates were investigated at various growth stages. Correlation analyses between N.P.K contents and yield and use efficiency of N.P.K and other results were as follows. 1. According to concentration and its change at various growth stages N is similar to K and P, Ca, Mg are similar each other. 2. Yield showed significant positive correlation in most fields with nitrogen content just after thawing. However P and N content were more significantly correlated with yield just before freezing in Kangwon and Chungnam (northern and central province). At the other growth stages negative correlation trend was shown between yield and P, especially K. 3. N.P.K contents in plant increased with the increase of fertilizer rate clearly in early growth stage, and especially in nitrogen, indicating that N was relatively short than P and K in the later stage. N and K contents at various fertilizer rates also indicated a probable competition between them. 4. Fertilizer recovery (use efficiency) decreased in the order of N (55)>K (27)>P (12%) and that of N tended to increase with yield increase. 5. Most effective growth stage for nutritional diagnosis in relation to yield appears to be just after thawing or just before freezing. Nutritional criteria for N.P.K at various growth stages were proposed.

• Korean Journal of Environmental Biology
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• v.36 no.4
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• pp.680-686
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• 2018

Nitrogen fertilizers, hairy vetch, and slow-release complex fertilizers were applied to the soil during the cultivation of crops. The impact of these factors on $N_2O$ emission was quantitatively assessed and the GHGs reduction effect comprehensively evaluated. Among the three factors, the significant factors affecting $N_2O$ emission were mineral nitrogen>soil moisture>temperature. Yield and fertilizer utilization efficiency were highest in the slow-release complex fertilizer treatment. There was no significant difference in $N_2O$ emissions between the slow-release complex fertilizer treatments and the NPK+hairy vetch treatments. Comprehensive results showed that slow-release complex fertilizers treatment has high yield and fertilizer utilization efficiency but low $N_2O$ emission.

• Journal of the Korea Organic Resources Recycling Association
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• v.32 no.1
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• pp.5-11
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• 2024

Objective of this study was to evaluate the effect of organic fertilizer application on yield, soil chemical properties and soil organic carbon (SOC) in Korean cabbage cultural field. The experimental treatments consisted of none fertilizer (NF), NPK (inorganic fertilizer, N-P₂O₅-K₂O : 320-78-198 kg ha^-1), Organic fertilizer (OF 50, 100, 150% on application rate of standard 110 kg ha^-1 as N, topdressing: 210 kg ha^-1 as inorganic fertilizer). In experimental results, the growth characteristics and yields were not significantly different among the treatments. There was no significant difference in soil pH, available phosphate, ammonium nitrogen and exchangeable potassium, while organic matter, electrical conductivity and nitrate nitrogen were increased when organic fertilizer application. Also, SOC was increased with the application of organic fertilizers. These results showed that pre-application of organic fertilizer might be effective in a carbon storage in the field soil cultivating Korean cabbage.

• Korean Journal of Plant Resources
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• v.29 no.6
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• pp.650-657
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• 2016

Research has found that the management of the host plant is essential to mistletoe cultivation. A Trunk injection test on the host plant that contained a mixture of indole-3-butryc acid (IBA) and liquid fertilizer was conducted with respect to the improvement of the one year survival rate of mistletoe. As a result, the trunk injection experiments showed the effect of the IBA and liquid fertilizer mixture in all treatments. This mixture was effective to increase the survival rate of mistletoe by 20% with the IBA at 100 mg/L and Hyponex at 100 mg/L. The examination proved that the host plant fertilizer effect was the most effective treatment for organic fertilizer with 60% added NPK (4-2-1). Its effects were higher compared to the control at the length and diameter of one-years-old branches in the host plant, even when the parasitic mistletoe improved its growth in length, diameter, and number of branches. Comparing the control and host plant fertilizer, the latter was the most effective way to process 20 kg per a treatment effect in the experimental site and to process at any time after the inoculation. This treatment is effective to improve the growth of mistletoe by watering the host plant three times per week. Therefore, the management of the host plant is an essential element in the successful cultivation of mistletoe, not only to supply fertilizer and plant hormones to the host plant in the initial inoculation time but also to provide organic fertilizer and irrigation for the host plant.

• Korean Journal of Environmental Agriculture
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• v.33 no.4
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• pp.409-413
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• 2014

BACKGROUND: Large amount of veterinary antibiotics have been used in the livestock industry to prevent diseases and promote growth. These antibiotics are excreted through feces and urine in unchanged form and reach to agricultural fields via application of the livestock manure based composts. The purpose of this study was to evaluate the occurrence of tetracyclines-resistant bacteria in the soil received livestock manure compost for a long term. METHODS AND RESULTS: Tetracyclines (tetracycline TC, chlortetracycline CTC, and oxytetracycline OTC) resistance bacteria in the soil of rice-onion field applied pig manure compost (PM), in the soil of grass-rye field received cow manure compost (CM), and in the soil of rice field applied inorganic fertilizer (NPK) were determined. The soil received livestock manure composts clearly showed higher number of TC, CTC, and OTC resistance bacteria compared with the soil treated with inorganic fertilizer. The antibiotic resistant bacteria recovered appeared at 80 mg/L of tetracyclines was identified 1 specie, 6 genera 7 species, and 6 genera 7species in the soils received CM, PM, and NPK, respectively. The dominant resistant bacteria with the CM and PM application were Ochrobactrum and Rhodococcus. CONCLUSION: The application of livestock manure compost in the agricultural field is likely to contribute the occurrence of antibiotic resistance bacteria in the agricultural environment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.3
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• pp.358-367
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• 1983

To provide useful information on the improving cultural practices of mungbean, an investigation was made on variations of agronomic characteristics, yield, yield component, and grain quality of mungbean grown under three fertilizer levels of N, P, K with different upland soil, using varity, Gyeonggijaerae 5. The stem diameter of 5th internode was always thicker than 1st or 9th internode. Especially, 5th internode diameter was affected by the N, P, K fertilizer. The petiole angle under uncultivated land showed comparatively wider than that under cultivated land and the petiole angle increased from upper to lower node. LAI under cultivated land was higher than under uncultivated land. Especially, LAI of NPK, and NPK + compost treatments were generally higher than those of other treatments. LAI were remarkably increased by P application under uncultivated land. The grain yield was increased by increasing of the number of pods per plant, which were increased by K application under cultivated land, and P application under uncultivated land.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.5
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• pp.351-358
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• 2013

A suitable supply of mineral elements into shoot via a root system from growth media makes plants favorable growth and yield. The shortage or surplus of minerals directly affects overall physiological reactions to plants and, especially, strongly influences carbohydrate metabolism as a primary response. We have studied mineral uptake and synthesis and translocation of soluble carbohydrates in N, P or K-deficient tomato plants, and examined the interaction between soluble carbohydrates and mineral elements. Four-weeks-old tomato plants were grown in a hydroponic growth container adjusted with suboptimal N ($0.5mmol\;L^{-1}\;Ca(NO_3)2{\cdot}4H_2O$ and $0.5mmol\;L^{-1}\;KNO_3$), P ($0.05mmol\;L^{-1}\;KH_2PO_4$), and K ($0.5mmol\;L^{-1}\;KNO_3$) for 30 days. The deficiency of specific mineral element led to a significant decrease in its concentration and affected the concentration of other elements with increasing treatment period. The appearance of the reduction, however, differed slightly between elements. The ratios of N uptake of each treatment to that in NPK sufficient tomato shoots were 4 (N deficient), 50 (P deficient), and 50% (K deficient). The P uptake ratios were 21 (N deficient), 19 (P deficient), and 28% (K deficient) and K uptake ratios were 11 (N deficient), 46 (P deficient), and 7% (K deficient). The deficiency of mineral elements also influenced on carbohydrate metabolism; soluble sugar and starch was substantially enhanced, especially in N or K deficiency. In conclusion, mineral deficiency leads to an adverse carbohydrate metabolism such as immoderate accumulation and restricted translocation as well as reduced mineral uptake and thus results in the reduced plant growth.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.5
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• pp.290-295
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• 2002

Fertilizer granulation test was carried out by a small pan granulator. A premixture composed of SOP 60%, urea 22% and RP powder 18% was rolled in the pan granulator while 10% phosphoric acid solution(binder) was sprayed on the rolling powder bed. Granules were developed very fast along with a little amount of binder. Hardness, brittle ratio in water and hygroscopicity of granules were improved enough to evaluate physical properties of the fertilizer. Growth responses of tobacco plant to the fertilizer were investigated at seedling and flowering stage by pot experiment under plastic film roof. Seedlings showed poor growth at nursery pot cell. In virgin soil with deficient available phosphate tobacco plant showed poor growth until budding and flowering stage but good growth in tillage soil with high cumulative phosphate.