• Korean Journal of Soil Science and Fertilizer
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• v.37 no.3
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• pp.149-155
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• 2004

This study was conducted to evaluate the availability of liquid pig manure (LPM) as a substitute for chemical fertilizer (CF) in double cropping system of rice followed by onion. The LPM applied for rice in silty clay loam soil cultivated in the double cropping system with onion contained $3.8g\;N\;kg^{-1}$, $1.8g\;P_2O_5\;kg^{-1}$ and $2.7g\;K_2O\;kg^{-1}$. The LPM applied for onion after rice contained $4.9g\;N\;kg^{-1}$, $1.4g\;P_2O_5\;kg^{-1}$ and $2.1g\;K_2O\;kg^{-1}$. Soil pH increased after rice culture irrespective of treatments. The rice growth and grain yield among CF and LPM applications were not significantly different. The application of LPM without top dressing of CF delayed onion growth at mid and late stage. But when the LPM was applied as basal fertilizer and CF was added for top dressing, onion growth was maintained until late growth stage. The nutrient uptake of LPM and top-dressing by CF (rice)/LPM and top-dressing by CF (onion) were similar to CF (rice)/CF (onion). The highest yield of onion bulb was 58.5 Mg ha-1 at CF (rice)/LPM and top-dressing by CF (onion) treatment, but showed no significant difference with other treatments except CF (rice)/LPM only (onion) and no fertilization (rice)/no fertilization (onion) treatments. In conclusion, in double cropping system of rice followed by onion, rice was capable of being grown by only liquid pig manure but additive chemical fertilizer was needed for optimal onion growth.

• Journal of Sericultural and Entomological Science
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• v.9
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• pp.49-66
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• 1969

Eri-silkworm is known as a tropical insect where as poly-voltine type in that area. It eats caster oil plant leaves which are cultivated as an every year cultivatable seed oil use in this country, even though it grows for many years in tropical countries. That is why, farmers have freedom for its cultivation in any year if they want. Therefore, eri-silkworm rearing service is flexible for its diet procurment as wish of farmer. The eri-cocoon price or economical fluctuation may be reactable for the rearing work not like as mulberry cocoon. Fortunately, it also eats cynthia tree leaves. Standing from such a easy condition, the authors have studied about this problem since 1963 to develope a culturing method of eri-silkworm rearing in this country and the authors brought out the matters to be produced as an industry scale. Here, the authors summarized their works of the results covering with thirty three work tables. The obtained results are as follows.

• Journal of Sericultural and Entomological Science
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• v.25 no.1
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• pp.1-20
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• 1983

It has been known that the insect molting hormone and its analogues exist also in plant kingdom and their concentration has been found to be about 0.1~2.0% of dry matter, which is equivalent to $10^3{\sim}10^5$ times of those in insects. This study was carried out; 1) to isolate the phytoecdysones from Korean Achyranthes radix and characterize their physico-chemical properties. 2) to investigate the biological activity of this phytoecdysone on Bombyx mori larvae. The resuls were summarized as follows; 1. The extraction method of phytoecdysones was optimized by three consecutive reflux for 1hr using 200g of dried and milled radix per 1l methanol. 2. The purification from the crude extract was made by a series of steps such as precipitation of gum-type polymer with n-Butyl acetate, adsorption on technical grade silica and chromatography with neutral alumina. The conditions of each step were optimized and the resulting crude crystal was about 500mg per kg dry radix. 3. The crude crystal from the cultivated Achyranthes(Achyranthes japonia) contained ecdysterone (20-hydroxyecdysone) and inokosterone in the proportion of one to one. In order to separate these, a series of processes such as acetylation, separation by alumina column chromatography deacetylation by alcoholysis, deionization and crystallization were introduced and optimized 125mg of ecdysterone and 18mg of inokosterone per kg dry radix were thus obtained. 4. The wild Achyranthes (Achyranthes obtusifolia) radix was found to contain the ecdysterone only. A 285mg of ecdysterone was crystallized per kg dry radix. 5. Isolated ecdysterone, inodosterone and acetylated compounds were characterized by IR., UV., NMR spectroscopy, mp, TLC and densitometry. 6. Ligation experiment was undertaken to confirm the biological activity of the purified ecdysterone; the ecdysterone could induce larval-pupal metamorphosis in the ligated abdomen of 4th instar larvae injecting 0.5~1.0${\mu}g$. 7. By ecdysterone feeding experiment using artificial diet, it was elucidated that the critical time of feeding would be the first half of each instar resulting in increased weight of silk layer. 8. The ecdysterone was fed to 5th instar silkworm at the level of 1, 2, 3, 5ppm of dry feed of artificial diet containing 5% mulberry leaves for 72hrs. At 2ppm of the concentration. body weight and silk layer weight were arrived at maximum. But at higher concentrations body weight and silk layer weight decreased than the control group. At 2ppm of the concentration, body weight was increased by 12.5%. 9. Feeding 2ppm of ecdysterone at the later half of 5th instar, the duration of larvae was shortened.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.983-991
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• 2012

These days, agricultural products cultivated in facilities occupy the highest percentage of agricultural output price. Specifically cucumbers have been one of the crops that farmers prefer to growing, because their prices were high. However, cucumber crop is sensitive to the soil and environments and it requires the exact crop management. In order to establish cultivation techniques for cucumbers, the current situation of cucumber cultivation was surveyed from ten cucumber farmlands; five farmlands of cucumber cultivation in forcing and five of semi-forcing practicing systems, respectably. The soil conditions were alluvial or valley in soil topology, moderately or poorly drainage in soil drainage classes, coarse loamy in soil texture family. Soil was managed with deep plowing combined with application of basal fertilizers such as compost, rice straw, oil cake, wood chip and chemical fertilizer. The whole soil was prepared in uniformly with rotary. Three major nutrients ($N-P_2O_5-K_2O$)of basal application were 815-464-529 kg $ha^{-1}$ in forcing and 197-135-151 kg $ha^{-1}$ in semi-forcing cultivation. Top dressing of fertilizer was supplied in fertigation system of macro and micro elements in 2~3 day interval with water irrigation. The average yields of cucumbers were $168t\;ha^{-1}$ with 381,000 thousand won $ha^{-1}$ in average gross profit (AGP) in forcing cultivation and $115t\;ha^{-1}$ with 177,000 thousand won $ha^{-1}$ in AGP in semi-forcing cultivation. Cucumber production during the winter season was considered to increase the gross profit because cucumber price tends to stay in high level during this time. The accumulation of soil chemicals like EC, available $P_2O_5$ and exchangeable cations could be controlled by rice straw application. The rice straw application increased soil temperature during the winter season, in exchange of soil air, and in extension of plant roots. In addition, the rice straw application somewhat affected decrease of salts accumulation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.5
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• pp.468-475
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• 1992

In order to understand more clearly the integration between N-assmilation and C-metabolism in relation to N fertilization, a pot experiment with 5 different level of N fertilization(0, 5, 10, 25, 50 mM NO$_3$$_{[-10]}$ ) was conducted in Manchester, U.K. The peas (Pisum sativum L., cv. Early Onward) were sown in vermiculate (5 cm depth) and cultivated for 6 days under temperature controlled dark room conditions ($25^{\circ}C$). The plants received frequent irrigation with a nutrient solution: it was fertilized every 2 days, 3 times a day at 10h, 13h, 16h respectively. Elevated NO$_3$$^{[-10]}$ concentration, the activity levels of NR, NiR, total GS(crude extract), GS$_2$(plastid) in both root and shoot were increased and reached the peak in 5～25 mM, except NiR specific activity which increased its activity continually until 50 mM NO$_3$$^{[-10]}$ treatment. Total activities of GS (crude extract) in both root and shoot became higher than those of GS$_2$(Plastid), and the activity ratios of total GS in the crude extract and GS$_2$ in the plastids were 3.0 to 4.3 in root, but 3.2 to 10.6 in shoot. It was concluded that the reductants and A TP from OPPP itself should be enough to achieve the high rate of NR, NiR, GS$_1$, GS$_2$ in plant root and shoot for reduction or assimilation of nitrogen, but these enzyme activities might be inhibited by an excess of NO$_3$$^{[-10]}$ influx over the reduction capacity.

• Korean Journal of Environmental Agriculture
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• v.24 no.2
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• pp.191-197
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• 2005

Green house soils have been intensively cultivated with excessive application of compost and chemical fertilizer for vegetable growth. The objective of this study was to establish the reasonable fertilizer application system for rice cultivation in green house soil. Field experiment was carried out with rice cv. Geumo-byeo 1 in Jisan series soil (fine loamy, mixed, mesic family of Fluventic Haplaquepts) that was previously cropped with green pepper (Capsicum annuum L.) for the last 3 years. Treatment consisted of conventional fertilization $(N-P_2O_5-K_2O=11-4.5-5.7kg\;10a^{-1})$, no basal fertilization, 50% reduction of basal fertilization no top dressing, bulk blending fertilizer, and no fertilizer. The value of pH, available phosphate, and exchangeable potassium after experiment was lower than those before experiment while organic matter content was not difference in all treatment. The value of salt elusion was the highest in no basal fertilization plot. The amount of $NH_4-N$ in soil was higher in growth stage of rice as fertilizer amount increased in 1998. The changes of plant height and tiller were higher as fertilizer amount increased. Thousand-grain weight as yield component was higher in no basal fertilization plot all the year because of decreasing panicle. There was no significant difference in rice yield between treatments in 1998. However, conventional fertilization resulted in significantly increased rice yield in 1999. Nitrogen use efficiency was the highest in no basal fertilization plot in 1998 and in conventional fertilization plot in 1998. Our results suggest that no basal fertilization be best to increase salt elusion with slightly increased yield in first year for rice cropping after vegetable harvesting, which method improves fertilization efficiency. However, conventional fertilization was good for second rice cropping after vegetable harvesting in greenhouse.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.1
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• pp.61-68
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• 1991

Thirty Bradyrhizobium japonicum isolates (10 strains per each soil) from 1 uncultivated [Sangnam(Soil 1), Milyang]- and 2 cultivated [Dong(Soil 2)and Chinbuk(Soil 3), Changweon] upland soils in Yeongnam area were evaluated on their symbiotic effectiveness to soybean [Glycin max (L.)] cv. Korean Jangbaekkong and American Clark and examined on their serological diversity. The results obtained were summarized as follows : 1. On symbiotic effectiveness of B. japonicum with plant genotypes, isolates showed a relatively high value of nodule mass in Jangbaekkong cv. and of shoot dry weight and total nitrogen in Clark cv. demonstrating the order of Soil 1> Soil 2> Soil 3 isolates. 2. Among 30 B. japonicum isolates, YCK 141 showed the best effectiveness on mean nitrogen fixation of two cultivars. 3. Thirty indigenous B. japonicum showed 6 types of serological diversities in the immunoblot analysis which were present in various proportions at Soil 2(5) and Soil 3(5) except Soil 1 where all isolates fell into the YCK 117 serogroup. And their distribution order was serotype YCK 117( 12 strains) > USDA 1l0(5strains), USDA 123(5 strains) > YCK 150(4 strains) > YCK 141(3 strains) > YCK 226(1 strain). 4. Especially, 10 isolates from Soil 1, an uncultivated orchard, showed a very homologous pattern in not only effectiveness but serological distribution. It seemed to indicate that the isolates were typically affected by numerous physical and environmental factors of the soil.

• Food Science and Preservation
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• v.22 no.4
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• pp.567-576
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• 2015

The purpose of this study was to evaluate the functionality of ethanol extract of Aster scaber by analyzing anti-oxidant components and anti-oxidant activities, which was grown in wild and culture field. The yields of Aster scaber ethanol extracts were high after blanching treatment. The polyphenol content of dried Aster scaber grown in wild was 35.59 mg/g, which was higher than that of Aster scaber grown in culture field. The electron donating ability in all Aster scaber extracts were increased with increase in extract concentration, and the electron donating ability was the highest in extracts of the dried Aster scaber after blanching. The SOD-like activity of Aster scaber was the highest in its extract grown in wild field. In addition, the SOD-like activities of extracts of the dired Aster scaber after blanching were highest among the extracts of cultivated Aster scaber. The nitrite scavenging ability of extracts was increased at pH 1.2, and those was the highest in wild fresh Aster scaber. The inhibition effects on xanthine oxidase and tyrosinase were increased with increase in extract concentration, and the inhibition effects of extracts of Aster scaber in wild field were higher than those grown in culture field. Therefore, the consumption of Aster scaber would provide beneficiary effects due to its antioxidant activities and prevention of aging. The development of various processed food using Aster scaber will promote the consumption and its values.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.6
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• pp.12-23
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• 2019

The purpose of this study was to develop and study an experiential natural education program that could emphasize the importance of the natural environment by providing natural experience opportunities using the natural resources of the urban forest parks using Youngheung Park in Suwon, Gyeonggi Province as a target site. The research target was limited to Suwon Yeongheung Park, which had the potential to become a place for education, where urban forest conservation and sustainable use already coexist. The natural education resources derived by surveying and analyzing the basic environment and the ecology of plants and animals in Suwon Yeongheung Park were organized to establish program goals, directions, and themes. Suwon Yeongheung Park is a water-rich forest that forms an ecological system of wetlands, including rice paddies, muknon wetlands, and dungbun, near a valley area. The U-shaped walkway was smoothly formed along the ridge and includes Doran-gil, which is among the Palochrome Road, designated by the city of Suwon. The soil is acidic, with a pH 4.40, due to urban pollution and acid rain, and is not good for plant growth. Most of the artificial forests, natural forests, and arable land were found using land use and extant life surveys. Old trees were distributed in artificial forests, the oak clusters in natural forests, and the fields and darrinones were distributed in the arable areas. As the forest vegetation declined, the cedar forest was underway, and the cedar trees and red bean pear trees were cultivated due to their adaptability to the urban environment. There are 13 large of 180 sacks, one being 109 centimeters in diameter, the largest silvery tree, and 105 oak trees, provide food and shelter for animals. Six species of waterfowl that used the 22 kinds of forest wetlands, while four species of amphibians and two species of reptiles reside in the wetlands. Natural Monument No. 327, Mauryuk, Class II Endangered Wildlife, was also observed in the wetlands. Eight other species of surface dragonflies and three species of butterflies were observed. By systemizing the resources, members, and characteristics of the forest ecosystems in Suwon Yeongheung Park based on five criteria, the program for a hands-on natural education was presented with the aim of understanding the urban forest ecosystem in Suwon Yeongheung Park, having an affinity with the city, and recognizing its relationship with the community and society. However, further research is needed as there are limitations of research on programs characterized by different ages and classes.

• Journal of Bio-Environment Control
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• v.16 no.4
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• pp.395-406
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• 2007

The twenty seven wrap-up vegetables (13 Compositae, 14 Brassicaceae) and seven herbs (6 Labiatae, 1 Umbelliferae) were cultivated with a deep flow technique (DFT) hydroponic beds and treated with 3 levels of nutrient solution concentrations of 1.2, 2.4, and $3.6dS{\cdot}m^{-1}$ in summer and autumn season. The pH and electrical conductivity (EC) change of nutrient solution, fresh weight, and mineral contents of plants were investigated. The pH was maintained lower in high electrical conductivity (EC) treatment and in summer than autumn. EC of nutrient solution in EC $3.6dS{\cdot}m^{-1}$ treatment increased up to $4.8dS{\cdot}m^{-1}$ during the growing period in summer season. The growth of tested plants showed high variations by plant species and nutrient solution concentrations. The coefficient variation (CV) of the shoot fresh weight of plants was higher in summer than autumn. The growth of Compostiae and herbs was better at EC $1.2dS{\cdot}m^{-1}$, and 14 Brassicaceae was better at EC $2.4dS{\cdot}m^{-1}$ in summer. In autumn, the growth was better at EC $2.4dS{\cdot}m^{-1}$ in all plants except kale 'TBC F1' and red rape 'honchaetae'. In mineral contents, total nitrogen and potassium were higher in autumn than summer. Total nitrogen, potassium, calcium, magnesium were higher in Brassicaceae than others. Iron and manganese, however, were higher in Compositae. As the results, this study suggests that mixed planting of 27 wrap-up vegetables and 7 herbs in DFT hydroponics in two seasons was possible and EC $1.2dS{\cdot}m^{-1}$ in summer and EC $2.4dS{\cdot}m^{-1}$ in autumn be recommended as for the nutrient solution concentration to produce them safely year round.