• Korean Journal of Soil Science and Fertilizer
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• v.25 no.3
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• pp.275-280
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• 1992

Inoculation responses of alfalfa[Medicago sativa(L.) Vernal] to Rhizobium meliloti with nitrogen fertilization were characterized by soil populations and plant yields from 1989 to 1991 at cultivated upland soil, which contained $3.1{\times}10$cells of R. meliloti/g.soil. The results obtained accordingly to fertilizing with 8Kg N/10a and differently inoculating the host such as initial and annual inoculation methods were as follows : 1. Soil populations of R. meliloti were increased more at no nitrogen fertilized condition compared to nitrogen fertilized condition to 2nd year experiment from 1st year that came up $1.6{\times}10^3$cells/g.soil, but at 3rd year the trend was reversed. Between inoculation methods, on the whole, the annual inoculation caused more populations, which were $2.0{\times}10^4$cells/g.soil in maximum number. And the populations declined after winter but recovered passing through summer season. 2. Alfalfa yields were mainly influenced by rhizobial populations rather than by fertilizing nitrogen showing a significant correlation(Y=0.36+0.287X, $r^2=0.58^{**}$) with the former. The increased extents of yields obtained by inoculation at no nitrogen and nitrogen fertilized conditions, respectively, were 66 and 10% in 1st : 13 and 20% in 2nd : 19 and 13% in 3rd year experiment with the initial inoculation, and were 66 and 10% in 1st ; 30 and 20% in 2nd : 35 and 36% in 3rd year experiment with the annual inoculation. 3. The results demonstrated the importance of inoculating, if possible, annual inoculating alfalfa to get much yields even at cultivated upland soil.

• Weed & Turfgrass Science
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• v.3 no.2
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• pp.95-101
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• 2014

This study was conducted in order to utilize the basic data for weed control by surveying the occurrence of weed species and the degree of damages caused by those weeds occurred in cultivated Ligularia fischeri fields. Survey was carried out five times, on May, June, July, August and October in 2013. The weed flora was composed of a total of 104 weeds, 37 families, of which 55 species were annual, 25 species were biennial, and 24 were perennial plants. Twenty-six exotic species were included as well. Dominance was the highest with Chenopodium album followed by Stellaria aquatica, Echiochloa crus-galli, Conyza canadensis, and Artemisia princeps etc. in order. In the PCA plot analysis, weeds occurred in cultivated L. fischeri fields were divided into three groups, Persicaria thunbergii-Bidens frondosa community, Chenopodium album community and Capsella bursapastoris community. The degree of damages in cultivated L. fischeri fields was investigated by weighing roots of L. fischeri. We found that 56% decreased root weight in no weeding plots comparing to that in weed management plots. We infer from this result that decreased roots will affect to the growing of L. fischeri in following year.

• Korean Journal of Medicinal Crop Science
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• v.7 no.4
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• pp.308-313
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• 1999

Direct seeding is a cultivation method of Korean ginseng which can cut down production cost and increase productivity. This study was conducted to obtain detailed information about this method and to aid the development of it in Korea. Major pre-crops before ginseng cultivation were rice, corn and rye, and organic matters, such as rice straw, rye straw and poultry feces were used for basal fertilization. In direct seeding of the ginseng field, seeding density was 196 to 210 seeds per $3.3m^2$ and germination ratio was 67%. Survival ratio of 4-year-old ginsengs which were products of direct seeding was 51%, and more than 100 plants per $3.3m^2$ survived. The most critical diseases in the directly seeded ginseng field were grey mold, damping off, and stem diseases including stem spot disease. Plant growth of the ginseng cultivated by the direct seeding method was not different from the ginseng cultivated by transplanting method. But the root of the ginseng cultivated by the direct seeding method took the shape of a shorter main root compared to the ginseng cultivated by the transplanting method. Root yield per $3.3m^2$ of the direct seeding ginseng field was larger compared to the field of the transplanting cultivation.

• Korean Journal of Plant Resources
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• v.33 no.4
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• pp.255-262
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• 2020

The aim of this study was to investigate the correlation between growth characteristics and ginsenoside contents of 7 and 13-year-old wild-simulated ginseng. The results of growth characteristics such as rhizome length, root length, fresh weight, cross-section area, surface area and volume were shows significantly higher in 13-year-old wild-simulated ginseng compare to 7-year-old wild-simulated ginseng. In the case of 11 ginsenoside contents, the contents of G-Rb1, Rb2, Rc, Rd, Re, Rf, Rg1 and Rg2 were shows significantly higher in 13-year-old wild-simulated ginseng compare to 7-year-old wild-simulated ginseng. In addition, in the comparative analysis of ginsenoside contents between wild-simulated ginseng and cultivated ginseng, 13-year-old wild-simulated ginseng was shows significantly higher G-Rb1, Rd, Re, Rf and Rg1 ginsenoside contents compare to 4-year-old and 5-year-old cultivated ginseng. In the result of correlation analysis between growth characteristics and ginsenoside contents, the G-Rb1, Rb2, Rc, Rd, Re, Rf, Rg1, Rg2 ginsenoside was shows significantly positive correlation with rhizome length, fresh weight, cross-section area, surface area, volume, while as the contents of G-Rb1, Re, Rf, Rg2 was shows significantly negative correlation with shoot diameter. The results of this study was might be help to provide useful information on the establish quality standard by the investigate correlation analysis between growth characteristics and ginsenoside content of wild-simulated ginseng.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.3
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• pp.189-194
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• 1994

This experiment was conducted to obtain basic information on the improved methods of soil physico-chemical properties and sweet potato yield cultivated on a newly-reclaimed land, a Songjeong loam soil. The crop was cultivated under the six different treatments for 4years since 1985 in the field conditions. Annual changes of soil properties and sweet potato yield were investigated and analyzed. Soil bulk density increased from the second year, and also soil hardness of topsoil increased, but that of subsoil had not tendency. Average yield of sweet potato for 4years in the integrated improvement plot was 32.68ton/ha, which is increased by 59% in comparison to that of the control plot. Crop yield was in order of integrated improvement>phosphate>subsoiling>lime>compost>control plots. The soil properties of the topsoil which showed high correlation coefficient to sweet potato yield were bulk density, hardness and cation exchange capacity(CEC), and those of the subsoil were bulk density, soil moisture and CEC. Ratios of changes of soil properties except organic matter content showed high significancy to sweet potato yield. Soil physico-chemical properties of the 4th year without soil conditioners application were worse than those of 3rd year.

• Korean Journal of Medicinal Crop Science
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• v.7 no.4
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• pp.282-287
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• 1999

This study was conducted to investigate the effects of different soil texture in agronomic characteristics, root yield and quality of baloon flower (Platycodon grandiflorum A. DC.). Three kinds of soil texture, sandy loam, silt loam and clay loam, were tested for two years. Baloon flowers were seeded with 20cm row space and cultivated in the one square meter pot with 0. 6m depth. Fifty plants per pot were remained. In growth characteristics of one-year-old plants, shooting date was not significantly different according to the changes of soil texture. The ratio of stem growth was highest between July and August. In two-years-old plants, it was showed between May and June. Plants grown on clay loam showed the highest growing characteristics than those of other soil textures. Dry root weight cultivated on clay loam was 274kg/10a in one-year-old and 934kg/10a in two-years-old plants. The content of ethanol extracts from root was highest at those of sandy loam as 47.1 % in one-year-old root. The crude saponin content was not different significantly among the three kinds of soil texture.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.2
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• pp.175-179
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• 1994

This experiment was carried out to investigate the effect of improved NPK fertilizer and ameliorator application methods on job's tears yield and soil properties in the newly-reclaimed land from 1985 through 1988. Job's tears height of integrated improvement plot was higher than the other plots, and increased from the 1st and the 2nd year, but decreased from the 3rd year when soil conditioner was not applied. Average yield of the crop in the integrated improvement plot was 2.16 t /ha being increased by 49% more than the control plot, and the yield was the greatest in order of integrated improvement>subsoiling>phosphate>lime>compost>control plot. Soil bulk density and hardness of the topsoil decreased to the 3rd year, but increased in the 4th year. Soil pH of the topsoil was not changed significantly by different soil depths and cultivated years.

• Korean Journal of Medicinal Crop Science
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• v.25 no.1
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• pp.1-9
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• 2017

Background: Some plants have harmful effects on fungi and bacteria as well as other plants. Incorporating such plant into soil as green manure is effective in reducing population densities of soil pathogens. Methods and Results: Twenty-three species of green manure crops were cultivated after the harvest of 6-year-old ginseng and then incorporated into the soil at the flowering stage. The following year, the root rot ratio of 2-year-old ginseng and soil chemical properties were investigated. In the absence of green manure addition, the $NO_3$ content, electric conductivity (EC), and K content decreased by 95%, 79% and 65%, respectively. In the presence of green manure addition, $P_2O_5$ and $NO_3$ contents reduced by 41% and 25%, respectively. The "survived root ratio" of 2-year-old ginseng significantly increased by 56.2%, 47.5%, and 47.3%, in the Sorghum sudanense, Ricinus communis and Helianthus tuberosus treatment, respectively. In addition, there was a significant increase in the "survived root ratio" in the Secale cereale, Chrysanthemum morifolium, Atractylodes macrocephala, and Smallanthus sonchifolius treatments. The "survived root ratio" of ginseng showed a significant positive correlation with the soil pH and a negative correlation with the $NO_3$ contents, and EC. Conclusions: Cultivation of plant form the Chrysanthemum family as green manure, using mainly the rhizomes was effective for the control of root rot disease of ginseng.

• Journal of Korean Society of Forest Science
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• v.3 no.1
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• pp.23-27
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• 1963

A research was made through a experimental cultivation during a period of 7 years (1956~1962) to determine the yearly yield, the total gross yield over 7 year's period and the maximum availability of stock timbers used as the germination bed of cortinellus edodes (Berk) Ido et Imai. The results are summarized as follows : (1) Research and plot scheme: Two experimental plots were established-plot "A" in the experimental forest of this college; plot "B" in the campus woods, 400 timber beds were furnished in each. The kinds of timbers used are : Quercus Serrata Thumb 140. Quercus acutissima Carr. 140, Quercus crispula BI 120. The environmental condition in plot "A" was better then that in plot "B" and the former showed greater yield than the latter. (2) yield : In plot "A" the total yield was 58.875kg and some of the timbers was still continuing germ in this seven after closing of the plot. In plot "B" the total yield was 56.90kg and after the sixth year no more germination was observed. In conclusion, plot "A" showed greater yield and longer germination than plot "B". (3) Germination efficacy and the kinds of timber: The best result was abserved on Quercus serrata, thumb Quercur acutissima Carr, stood next and then came Quercus crispula BI. Betula platyphylla was tried, but the result was worst. (4) Availability limits of timber beds: Quercus serrata Thumb with diameter 12~15cm had the longest availability more than (6~7 years) and Quercus acutissima Carr with diameter 12~15cm showed 6~7 year's availability. The shortest availability was found in Quercus crispula with diameter 6~9cm. Any kinds of timber with diameter 6~9cm had only 4~5 years of availability (5) In the table showing the yearly germination quantity, the figure of December and Jaunary of the 4th and 5th year shows the yield obtained in the semi-cellar paper house. This tells that there is good promise of winter cultivation of cortinellus edodes (Berk) Ido et Imai on matured timber beds.

• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.2
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• pp.113-123
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• 1997

This study was initiated to build runoff plots, install soil and water quality monitoring systems and collect background data from the plots and neighboring soils as the 1st year study of a 5 year project to assess soil quality and develop the management practices for environmentally sound agriculture in mountainous soils. Eleven $3{\times}15m$ runoff plots and monitoring systems were installed at a field of National Alpine Agricultural Experiment Station to monitor soil quality and discharge of nonpoint source pollutants. Corn and potato were cultivated under different fertilizer, tillage and residue cover treatments. The soil has a single-layered cluster structure that has a relatively good hydrologic properties and can adsorb a large amount of nutrient. Concentrations of T-N, $NH_4$-N, and $NO_3$-N of surface soil sampled in the winter were relatively high. Runoff quality in the winter and thawing season in the spring was largely dependent on surface freezing, snow accumulation, temperature, surface thawing depth and so on. Runoff during the thawing season caused serious soil erosion but runoff quality during the winter was relatively good. Serious wind erosion from unprotected fields after the fall harvest were obserbed and best management practices to reduce the erosion need to be developed.