• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2001.10a
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• pp.435-440
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• 2001

The purpose of this study was to evaluate mesh size and water velocity for the growth of filamentous periphytic algae(FPA). The growth experiment was carried out in the constructed pilot waterway system with nutrient-rich treated wastewater. Growth rate of FPA was highest at water velocity about 10 cm/s. The maximum standing crop of FPA was $253\;{\mu}g\;chl.a/cm^{3}$, and an average of the net productivity was $3.92\;mgDW/cm^{2}/day\;or\;25.3\;{\mu}g\;chl.a/cm^{2}/day$. Biomass development and growth rates of FPA were highest at the net with 20mm mesh size during the fall season and 10mm mesh size during the winter season.

• Korean Journal of Medicinal Crop Science
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• v.12 no.4
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• pp.273-278
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• 2004

The anticancer activities of the extracts from Acanthopanax senticosus Harms, Ephedra sinica Stapf, Rubus coreanus Miq and Artemisia capillaris Thunb were compared according to extract systems. About 70% of the growth of human hepatocarcinoma cancer cell was inhibited in adding 1.0 mg/ml of the water extract from Rubus coreanus Miq with ultrasonification at $60^{\circ}C$. The growth of human normal lung cell was limited to 25% in adding the extracts with ultrasonification at $60^{\circ}C$. The effect of extracts obtained by only water and with ultrasonification on different of human promyelocytic leukemia cells was also observed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.4
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• pp.436-441
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• 1985

The study was conducted to provide basic information to breeders and agronomists working with sesame. The grain weight and germinability were investigated for eight plant types classified by branching habit, capsules per axil, and carpels and loculi of a capsule. Two typical cultivars were chosen for each plant type among 527 gene pools. Dry weight of one thousand grains was increased rapidly from 25th to 35th day after flowering, and reached peak on 40th day after flowering in upper part capsules and 45th day after flowering in lower and middle part capsules, so that this period was considered to be of physiological maturity in each capsule bearing part. Side capsules on main stem and branch capsules were lighter than central ones of main stem, and upper capsules of four carpels eight loculi type decreased more seriously. BTB type demonstrated relatively better growth compared to the growth of BTQ type in one thousand grain weight. The maximum grain filling duration for germination percentage increased rapidly up to 40th day after flowering. Above 70% germinability was obtained from 40th day after flowering. Harvesting time of physiological maturity was considered to be 45th day after flowering with peaks of 2.14g of one thousand grain weight, 26% of grain water content and 90% of germinability.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.4
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• pp.481-487
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• 1983

The need to synchronize flowering in two lines of different maturities is frequently encountered in hybrid com (Zea mays L.) seed production. To establish the methods for synchrony of flowering in parent lines of different maturities be effects of clipping at 4 and 6-leaf stages of growth and two levels, clear polyethylene mulching and five different planting dates on flowering date growth and seed yield of two dent com inbred lines of different maturities were evaluated Clipping just above the shoot-apex delayed pollen sheeding 6 to 9days and silking 5 to 13 days but reduced stand and seed yield 30 to 70% and 67 to 81%. respectively. Clipping 5cm above the shoot apex delayed flowering 1 to 4 days without stand reduction but reduced yield 3 to 29%. Laterclipping was slightly more effective for delaying flowering than earlier clipping but reduced stand more severely when clipped just above the shoot apex. Under clear polyethylene film mulching, flowering of two lines was 13 to 15 days earlier and seed yield of B68 (late line) was significantly increased. As planting was delayed from April 18 to June 13, the number of days from planting to flowering of two lines decreased due to increase in air temperature. However, growing degree days (GDD) from planting to flowering of each lines was similar regardless planting dates indicating that GDD can be satisfactoryly used for choosing the planting dates of parent lines of different maturities. Seed yields of two lines were decreased with delaying planting dates.

• Korean Journal of Medicinal Crop Science
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• v.22 no.2
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• pp.127-133
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• 2014

This experiment was carried out to investigate the effect of several organic compost on the growth and root yield of Angelica gigas Nakai with organic cultivation. After fertilizing the soil with organic fertilizer, the dry weight of liming fertilizer showed a slow change, while microorganism fertilizer decreased about 29% until 20 day after fertilizing. At 110 days after fertilizing, microorganism fertilizer decreased more than liming fertilizer. Liming fertilizer decomposed slowly, while microorganism fertilizer decomposed early on rapidly but gently after 20 days in decomposed rate of organic fertilizer. Dried root yields per 10a of A. gigas were not significance between 277.6kg in conventional fertilizer and 277.7kg, 280.5kg in N 1.5, N 2.0 times of microorganism fertilizer. Decursin and decursinol angelate contents in A. gigas were 9.08 ~ 9.07% from N 1.0 and N 1.5 times in liming fertilizer, and 7.94 ~ 8.12% from N 1.5 times and N 2.0 times in microorganism fertilizer, compared to 7.31% of conventional treatment.

• Journal of The Korean Society of Grassland and Forage Science
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• v.27 no.1
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• pp.1-8
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• 2007

This experiment was conducted to determine the effect of growth stage and variety on the yield and quality of whole crop rice (WCR) at National Livestock Research Institute, RDA from 2003 to 2005. Two types of rice ("Chucheong" for food and "Hamasari" for feed) were harvested at six different growth stages (heading, flowering, milk, dough, yellow ripening and fully ripening stage). Crude protein content decreased with progressed maturity at harvest. As growth stage delayed, TDN (total digestible nutrient) content of all rice varieties increased. The average TDN content of two type of rice was about 60% (59.3) which was calculated from ADF(acid detergent fiber) content. The contents of ADF and NDF(neutral detergent fiber) decreased with harvest maturity. The highest DM(dry matter) yield was at the ripening stage (p<0.05) and "Chucheong" gave higher yields than for "Hamasari". In this experiment, the DM yield of all varieties was low. The yield of TDN followed a similar trend to DM yield. According to this results that dough to yellow ripening stage of harvest maturity will be recommendable as proper harvest time for whole crop rice silage.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.6
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• pp.345-350
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• 2006

Recently we have interest on rice products developed by environment-friendly management. The technology of paper mulching was practised without herbicide in machine transplanting cultivation of paddy. A field experiment was conducted on Gangseo series (coarse loamy, mixed, nonacid, mesic family of Aquic Fluventic Eutrochrepts) at the National Institute of Crop Science (NICS), RDA, Suwon, Gyeonggi province, Republic of Korea in 2004. This experiment was carried out to evaluate rice growth, weed control and nitrogen efficiency by the different controlled-release fertilizer levels in paper mulching transplanting. Treatments consisted of conventional fertilization, controlled-release fertilizer (100%, 80%, 60%) compared with nitrogen amount ($110kg\;ha^{-1}$) of conventional fertilization and no nitrogen plot. Mulching paper consisted of recycled paper which was coated with biodegradable plastics. There were no differences between conventional rice transplanting and paper mulching on missing hills. Weed occurrence and control were diverse and low as fertilizer amount increased. Plant height and tiller number per hill increased as fertilizer amount decreased. There were no difference between controlled-release fertilizer 80% and conventional fertilization plot on rice growth traits. Leaf color and $NH_4{^+}-N$ in soil had similar trends. There was no difference in yield between controlled-release fertilizer 80% and conventional fertilization plot. Agronomic nitrogen-use efficiency was high as fertilizer amount decreased. Therefore, these results suggested controlled-release fertilizer 80% should be optimum amount under paper mulching transplanting of rice considering weed control, rice growth and nitrogen efficiency.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.5
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• pp.543-547
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• 1995

This study was conducted to light intensity and night interruption on leaf production in perilla. Using two cultivars ; og-dong and Yeup-sil. The present studies were conducted to investigate effect of the light intensity and night interruption for prolongation of vegetative growth by flowering inhibition in the National Honam Crop Experiment Station, R. D. A, Iri, Korea. The results are summarized as followes, varietal differences of days to flower initiation were not significant by the light intensity and night interruption, however differences of days to flower initiation light intensity or night interruption treatment were higly significant. Flowering of perilla was prolongated in high light intensity and in long night interruption. Between the factors treated flowering of perilla was more influenced by light intensity than night interruption. Days to flower initiation of perilla were light intensity(0.5∼1 Lux) in 30 mins night interruption, however 3∼10 light intensity in 60 mins night interruption and 30∼100 Lux light intensity in 10, 30, 60 mins night interruption treatment were not flowering. Plant height, leaf area and dry weight of perilla were the highest in 30∼100 Lux light intensity treatment than in the other treatments. The results would be avaliable establish year-round production methods for low cost of perilla leaf.

• Horticultural Science & Technology
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• v.18 no.3
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• pp.334-341
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• 2000

To develop a nutrient solution for a closed hydroponic system in potato (Solanum tuberosum L.) 'Atlantic' and 'Superior' potatoes were grown with the nutrient solutions whose strengths were 0.25, 0.5, 1.0, and 1.5 of the concentration of the nutrient solution developed by the National Horticultural Experiment Station in Japan. The best results in potato growth and yield were obtained with 0.5 and 1.0 strength nutrient solutions, and nutrient compositions for potato were determined based on the 1.0 strength nutrient solution; $14.4me{\cdot}L^{-1}\;N,\;4.2me{\cdot}L^{-1}\;P,\;7.5me{\cdot}L^{-1}\;K,\;5.5me{\cdot}L^{-1}\;Ca$, and $3.5me{\cdot}L^{-1}\;Mg$ for stolon growth stage and $14.8me{\cdot}L^{-1}\;N,\;4.0me{\cdot}L^{-1}\;P,\;8.5me{\cdot}L^{-1}\;K,\;6.5me{\cdot}L^{-1}\;Ca$, and $3.0me{\cdot}L^{-1}\;Mg$ for tuber growth stage. To examine the suitability of the nutrient solutions developed for potato, the strengths of 1.0 (PS 1.0S), 0.75 (PS 0.75S), or 0.5 (PS 0.5S) were compared with half-strength of Japanese Horticultural Experiment Station' solution (JH 0.5S). Changes in pH, EC, and mineral concentrations in nutrient solutions depended more on solution strength and growth stage than on the type of nutrient solution. However, most elements in solution remained constant with plant age in PS 0.75S solution during stolon growth stage, and in PS 0.5S solution during tuber growth stage. The greatest growth and tuber yield was obtained in the standard strength solution (PS 1.0S), and potato solution developed in this experiment was recommended for hydroponic culture of potato in a closed system.

• Korean Journal of Medicinal Crop Science
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• v.12 no.5
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• pp.355-359
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• 2004

A survey was conducted during $April{\sim}May$ 2004 to determine the occurrence and population density of plant-parasitic nematodes in ginseng (Panax ginseng C.A. Meyer) growing fields, in major ginseng growing regions of Chungbuk, Chungnam, Gyeongbuk and Kyongki provinces. The survey revealed presence of eleven species of plant-parasitic nematodes namely, Criconemoides morgensis, Ditylenchus destructor, Helicotylenchus dihystera, Meloidogyne incognita, M. hapla, Paratylencgus lepidus, Pratylenchus penetrans, Psilenchus hilarulus, Trichodorus similis, Tylenchorhynchus claytoni and Xiphinema americanum. Frequency and density of each species were highly variable. M. incognita and M. hapla were the predominant species, their infestation observed in 46.3 and 39.4% fields with an average density of $78{\sim}254\;and\;76{\sim}211$ nematodes per $300\;cm^3$ soil, respectively. Whereas, T. similis and X. americanum were rarely observed; only in 2.3 and 1.8% of surveyed fields and their density was $10{\sim}17\;and\;7{\sim}10$ individuals per $300\;cm^3$ soil, respectively. They are recorded herewith for the first time from ginseng fields of Korea. In nematode-infestated fields, stunted plant growth with chlorotic leaves, and wilted plants were observed in patches.