• Korean Journal of Soil Science and Fertilizer
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• v.43 no.4
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• pp.514-521
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• 2010

Fertilizers, plant growth promoting microbes and plant growth regulators should be combined together and used in order to achieve a maximal plant growth and yield in modern sustainable and ecological agricultural systems. In this study rhizosphere inoculation of Methylobacterium oryzae CBMB20 and foliar application of methanol were tested for their ability to promote the growth of red pepper plant at different levels of organic fertilizer. Rhizosphere inoculation of M. oryzae CBMB20 and foliar spray of methanol could promote red pepper plant growth and yield, and the growth promoting effect induced by the combined treatment of M. oryzae CBMB20 inoculation and foliar spray of methanol was more distinctive. This result suggests that a synergistic growth promoting effect of methanol spray and M. oryzae CBMB20 inoculation can be obtained in the combined treatment of the two growth promoting factors. The growth promoting effect was more significant in the lower fertilization rate, and the plant growth was not significantly different between 100 and 300% fertilizer treatments where both M. oryzae CBMB20 inoculation and foliar spray of methanol were included. This result indicates that, with the plant growth promoting effect of M. oryzae CBMB20 and methanol, fertilizer application rate can be profoundly reduced without any significant decreases in biomass accumulation and yield of crops.

• Korean Journal of Environmental Agriculture
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• v.33 no.3
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• pp.164-168
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• 2014

BACKGROUND: Increase in application of liquid pig manure(LPM) in agriculture as nutritional source has become a social issue due to its influence on water quality. Also, proper application methods have not been developed with respect to indigenous properties of LPM and soil physical properties. Therefore, we conducted this experiment to observe the infiltration characteristics and distribution of dissolved organic compounds of LPM in soils having different soil textures. METHODS AND RESULTS: To do this experiment, we collected three different soils and LPM. We analyzed the physical and chemical properties of both soils and LPM to determine the dilution ratios of LPM. The LPM diluted to 4 different ratios with distilled water was applied to the top of soil column. Infiltration rates were observed by time and depth until the amount of effluent collected from the bottom of the soil columns were stabilized while maintaining the hydraulic head 3 cm above the soil column. The results showed that infiltration rates increased with increasing dilution ratios in the order of sandy, loamy sand, and sandy loam. The time required to reach steady state was increased with decreasing sand contents clay. CONCLUSION: The size and amount of the dissolved organic compounds in LPM that can determine the efficiency as fertilizer and environmental problems as nonpoint pollution source in water quality have not been investigated with respect to behavior and transport of them in soil. Therefore, it requires further research how we can properly apply LPM as valuable fertilizer substitute for inorganic fertilizers.

• Korean Journal of Medicinal Crop Science
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• v.11 no.2
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• pp.155-160
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• 2003

This study was carried out to investigate propagation characteristics of seedling and rhizome in Epimedium koreanum NAKAI. Seed germination essentially needed after-ripening duration after harvesting for 250days and more by stratification. At $20^{\circ}C$ seed emergence days and root length were 8 and 0.46cm respectively. The above-ground part of E. koreanum grew until 60days after root cutting and the underground part of it grew after that time. The optimum amount of organic fertilizer was fermented cow-manure with husk 2,000kg/10a that showed $57.5cm^2$ in leaf area per plant, 6.2cm in new rhizome length, and 0.43% in icariin content, an index component of E. koreanum, while inorganic N-fertilizer made E. koreanum worse as it increased. In nutriculture extruded rice hull media was better for growth than perlite media at 1/2 NHRI solution.

• Korean Journal of Environmental Biology
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• v.34 no.3
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• pp.169-176
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• 2016

Although chemical fertilizers have a quick effect and broad applicability to agricultural fields, they have caused many problems like increasing soil acidity or decreasing soil organic matters. Environmental-friendly agriculture has been attempted in various ways such as organic agriculture, natural farming, low input and sustainable agriculture. The common interest of all environmental-friendly systems is to decrease burden to agricultural environment by low input of agricultural labor and materials. This study was conducted to estimate overwintering capacity and genetic distance among Chinese Milk Vetch (Astragalus sinicus, CMV) collections based on morphological characteristics and AFLP (Amplified fragment length polymorphism) analysis. Furthermore, the effect of CMV as green manure was observed in mix-cultured paddy fields with rice, sesame and sweet-potato. An another objective of this study was also to compare the pattern of weed occurrence in paddy fields with or without CMV and different rice transplanting times. The CMV collected from Paju district in central region of Korea was successively occurring through self-reseeding without artificial management. However, there was no noticeable difference in growth habit between Paju native CMV and introduced CMV from China which is currently used in farm fields. On the basis of multi-dimensional scaling and tree analyses, there are no significant difference of agricultural growth characteristics among Paju and chinese collections only excepting leaf angle and root length. The flowering time of Gurye collection was fast for 1 week as compared to other collections. AFLP that was commonly used for plant classfication, was applied to exam the genetic variation of CMV collections. Total 579 PCR products and 336 polymorphic fragments were generated using 8 primer pairs.

• Journal of Ginseng Research
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• v.40 no.4
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• pp.315-324
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• 2016

Background: Biocontrol agents are regarded as promising and environmental friendly approaches as agrochemicals for phytodiseases that cause serious environmental and health problems. Trichoderma species have been widely used in suppression of soil-borne pathogens. In this study, an endophytic fungus, Trichoderma gamsii YIM PH30019, from healthy Panax notoginseng root was investigated for its biocontrol potential. Methods: In vitro detached healthy roots, and pot and field experiments were used to investigate the pathogenicity and biocontrol efficacy of T. gamsii YIM PH30019 to the host plant. The antagonistic mechanisms against test phytopathogens were analyzed using dual culture, scanning electron microscopy, and volatile organic compounds (VOCs). Tolerance to chemical fertilizers was also tested in a series of concentrations. Results: The results indicated that T. gamsii YIM PH30019 was nonpathogenic to the host, presented appreciable biocontrol efficacy, and could tolerate chemical fertilizer concentrations of up to 20%. T. gamsii YIM PH30019 displayed antagonistic activities against the pathogenic fungi of P. notoginseng via production of VOCs. On the basis of gas chromatography-mass spectrometry, VOCs were identified as dimethyl disulfide, dibenzofuran, methanethiol, ketones, etc., which are effective ingredients for antagonistic activity. T. gamsii YIM PH30019 was able to improve the seedlings' emergence and protect P. notoginseng plants from soil-borne disease in the continuous cropping field tests. Conclusion: The results suggest that the endophytic fungus T. gamsii YIM PH30019 may have a good potential as a biological control agent against notoginseng phytodiseases and can provide a clue to further illuminate the interactions between Trichoderma and phytopathogens.

• Asian Journal of Turfgrass Science
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• v.12 no.1
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• pp.49-78
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• 1998

Nowadays, there are increasing demands of golf courses and it is necessary to make more golf courses than the present. To do this, we need to improve the environmental problems with the regional inhabitants, and it is said that the first thing to be considered in developing any golf course in Korea is to preserve the environment. In this context, the purpose of this study is to set forth several design factors to lessen the negative impacts which are accompanied with the development of golf courses. 1. The present conditions of golf courses in Korea Many new golf courses have come into being, particularly since the late 1980s, and now, in the year of 1997, over one hundred of golf courses are doing their business, yet the number of golf course is still less than required. So far, over a half of them have been made in the vicinity of Seoul on account of various reasons, and this has adversely affected on our natural environment. This unreasonable development of golf courses has caused serious water pollution, landslides and the other problems. Also, the topography of Korea is not good for golf courses. Although the demands of golf courses are increasing, the suitable sites for them are very limited, and therefore it is sometimes unavoidable to make golf courses on steep hills. Consequently, in designing golf courses in Korea, the most important thing is the balance between natural environment and artificial environment. 2.Eco-friendly golf course design factors 1) The concept of eco-friendly golf courses Ecologically sustainable and sound golf courses which are made by eco-friendly approaches 2)Basic conditions of eco-friendly golf courses (1)The most suitable sites (2) Conservation of existing ground as much as possible (3)Proper use of agricultural chemicals which have great impacts on the environment (4) Reasonable use of fertilizers (5) Developing a specialized fertilizer only for grass (6) Adaptation of organic agriculture (7) Improvement of grass sorts (8) Establishing reservoirs for purifying the water from golf courses 3) Eco-friendly golf courses (1) Location-Enough area /Gentle slope/Winding ground/Including lakes or streams /Not crossing wind's main direction Facing south or southeast /Suitable soIl for grass /Good drainage /Low level of underground water (2)Course layout and design -Consideration about existing contours as much as possible -Adaptation of Scotish design trend -Various holes' configuration -Consideration toward surrounding landscapes -Reducing grass areas -Giving buffer zones -Adapting computer methods in the process of site analysis and design (3) Eco-friendly considerations in constructing and managing golf courses -Protection of wildlife -Reuse of existing forests and preservation of topsoil -Renovation of old-fashioned courses -Reducing grass areas -Purification of water -Standization of management -Strict regulations against chemicals -Recycling organic materials -Through separation of the water inside golf courses and out of bounds -Getting proper construction works done in a due time 4.Eco-friendly considerations from a viewpoint of cultural environment 1) Well-matched landscape design and events planning 2) Implement of identifications and awarding systerns 3)Acknowledgement of superintendents' qualitications in the maintenance of golf courses 4)Increasing public golf courses and keeping good relationships with the neighbors near golf courses Key words: Pro-environmental development, Golf course.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.1
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• pp.40-48
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• 2013

This study evaluated the close crop recycling method by using the extract from defective onions. The mixture of the diluted extract (1/500) and nutrients was applied seven times on the onion leaves without spilling it onto the field. The yield and quality of the onions produced by this method (recycle) were compared to those grown organically (control) and conventionally (normal). The yield from the recycling field was increased significantly by 9% compared to that of the control field, while it was decreased by 11% compared to the normal field (p < 0.05). This lower yield was explained by the differences of the mulching vinyl and the fertilizers between the treatments which effect the onion growth during the winter. The content of quercetin in the onions from the recycling filed was increased significantly by 34% and 44% compared to those of the control and normal field, respectively (p < 0.05). It seemed that minerals and biologically active substances in the defective onion extract were effective in increasing the onion growth. In terms of soil microbial biomass, arbuscular mycorrhizal fungi was increased significantly in the recycle field by 40.1% and 30.6% compared to those of the control and normal fields, respectively (p < 0.05). On the other hand, microbial stress (cy19:0/18:1w7c) was decreased in the recycle field by 21.0% and 14.1% compared to those of the control and normal fields, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.6
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• pp.372-380
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• 2002

This study was conducted to investigate the changes of soil properties for potato and Chinese cabbage after application adding phosphorus and potassium fertilizers in the mounded highland soil from 1999 to 2001. Experimental plots were designed with control(NPK+Lime+Compost) and chemical improvement(Control+Application adding P and K). Mounded soil before field experiment of first year(1999) was low in organic matter, available phosphorus and exchangeable potassium, and the soil texture was loamy sand soil. After 3 years, the contents of soil organic matter increased a little, and available phosphorus and exchangeable potassium contents were remarkably increased. The crop growth in chemical improvement plot was better than control plot. Yield of chemical improvement plot in comparison with control plot was increased by 5~22% for potato and 6~25% for Chinese cabbage after 2~3 years.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.715-725
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• 2017

Importance of climate change and its impact on agriculture and environment has increased with the rise in the levels of Green House Gases (GHGs) in the atmosphere. To slow down the speed of climate change, numerous efforts have been applied in industrial sectors to reduce GHGs emission and to enhance carbon storage. In the agricultural sector, several types of research have been performed with emphasis on GHGs emission reduction; however, only a few work has been done in understanding the role of carbon sink on reduction in GHGs emission. In this study, we investigated ecosystem carbon balance and soil carbon storage in an agricultural paddy field. The results obtained were as follows: 1) Evaluation of soil C sequestration in paddy field was average $3.88Mg\;CO_2\;ha^{-1}$ following NPK+rice straw compost treatment, average $3.22Mg\;C\;ha^{-1}$ following NPK+hairy vetch treatment, and average $1.97Mg\;CO_2\;ha^{-1}$ following NPK treatment; and 2) Net ecosystem production (NEP) during the paddy growing season was average $14.01Mg\;CO_2\;ha^{-1}$ following NPK+hairy vetch treatment, average $12.60Mg\;CO_2\;ha^{-1}$ following NPK+rice straw compost treatment, and average $11.31Mg\;CO_2\;ha^{-1}$ following NPK treatment. Therefore, it is proposed that organic matter treatment can lead to an increase in soil organic carbon accumulation and carbon sock of crop ecosystem in fields compared to chemical fertilizers.

• Korean Journal of Plant Resources
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• v.35 no.5
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• pp.675-685
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• 2022

A comparative analysis was performed on the soil chemical properties of greenhouse or open field where flower crops were grown from 2018 to 2020. The pH of greenhouse soils was kept slightly higher than the optimum range suggested by Rural Development Administration and that of open field soils was maintained within the optimum range for three years. The contents of organic matter (OM) were within the optimum range without significant change every year in both soils. Available phosphate (Av. P₂O₅) of greenhouse soils was the highest at 560 mg/kg in 2018, but it decreased every year and fell within the appropriate range in 2020. The concentration of Av. P₂O₅ in open field soils have fluctuated for three years, not showing a significant difference. Electrical conductivity (EC) of greenhouse soils was higher every year than the standard, 2.0 dS/m, but EC of open field soils remained below the standard. The contents of exchangeable cations were higher than the standard, showing significant differences among the years in greenhouse soils. In open field soils, other cations except exchangeable K⁺ were maintained higher than the optimal level and only Ca²⁺ showed a significant difference among the years. In Pearson correlation matrices, the value of exchangeable Ca²⁺ had a significantly positive correlation with exchangeable Mg²⁺ content at both greenhouse and open field soils. Based on principal component analysis, the soils of greenhouse were distributed within the range of high concentrations of Av. P₂O₅, EC and exchangeable cations, while the soils of open field were characterized by low contents of OM and exchangeable cations. Therefore, it is essential to lower the concentration of exchangeable cations in greenhouse soils. It is common for the soils of open field to have a low OM content, so that organic fertilizers should be more actively applied to the soils in open field.