• Title/Summary/Keyword: Science culture

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A Comparative Study of Domestic Travel Patterns and Determinant Factors Affecting Satisfaction by Generations (대한민국 국민의 세대별 국내여행 방식 및 만족도 영향요인)

  • Mi-Sook Lee;Yoon-Joo Park
    • Information Systems Review
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    • v.22 no.2
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    • pp.137-166
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    • 2020
  • While South Koreans overseas travelling rate has been increased every year, domestic travelling rate has been at a standstill for several years. The purpose of this study is to analyze domestic traveling styles of Koreans according to their generations in order to provide generation-specific traveling services. For this purpose, we categorized the survey respondents into four different generations, which are Millennium (age 19~34), X generation (35~54), Baby Boomer (55~64) and senior by following the criterions of the Korea National Tourism Organization. After then, we analyze factors related to travel preparation process, the actual traveling activities and satisfaction after the travel. In this study, 16,713 data collected by the Ministry of Culture, Sports and Tourism are used. The results of this study show that Korean people tends to acquire domestic traveling information from their own or acquaintances past experiences. Also, they do not prefer the organized trip for domestic travels, thus do not buy package products a lot. In addition, natural scenery, rich in cultural heritage, and convenient accommodation are the most important determinant factors affecting the overall travel satisfaction of level for all generations. The traveling characteristics for each generation are as follows. Millennium get traveling information from the internet a lot, and more specifically, they refer portal sites and social network services (SNS) in many cases. Also, they tend to travel in summer peak season to popular destinations and pursues active traveling experiences. Generation X has similar traveling patterns with Millennium, however they major transportation method is using their own car. Also, transportation convenience and satisfactory leisure activity are important factors affecting the overall satisfaction level to Generation X. On the other hand, Baby boomer generation has a greater emphasis on appreciation of nature, visiting famous restaurants, and relaxation, rather than actively participating experiencing programs. They travel evenly in summer and spring/fall season to many different areas instead of focusing on popular tourist spots. In addition, shopping and eating delicious food are the important factors affecting the overall satisfaction level for them. Lastly, Senior generation has similar characteristics with Baby boomer in many ways, however, they travel a lot on the same day using public transportations or car rental service. They prefer spring and autumn trips rather than summer peak season, and tend to buy packaged travel products a lot compared with other generations. If these different traveling characteristics of each generation are considered for organizing and customizing tourism services, it is expected that domestic tourism satisfaction level will be ultimately increased.

Analysis of risk evaluation procedures and consideration of risk assessment issues of living modified organisms for agricultural use in Korea (농업용(사료용) 유전자변형생물체의 위해성심사 제도 분석 및 환경위해성평가 관련 쟁점에 대한 고찰)

  • Myung-Ho Lim;Sang Dae Yun;Eun Young Kim;Sung Aeong Oh;Soon-Ki Park
    • Journal of Plant Biotechnology
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    • v.50
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    • pp.275-289
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    • 2023
  • Since the implementation of the Living Modified Organisms (LMOs) Act in 2008, approximately 10 million tons of genetically modified corn, soybean, potato, canola, and other crops have been imported into South Korea. The import approval procedures have been completed for approximately 191 cases that include seven crops. Of these, approximately 90 cases, excluding crossbreeds of approved LMOs, were reviewed via consultation risk evaluation in four areas: human health, crop culture, natural ecology, and marine fishery environment. LMO developers in South Korea, who are major stakeholders in the import of LMO crops produced overseas, have raised concerns regarding procedural inefficiency in consultation reviews and the need of excessive reviews that are unsuitable for food-feed processing purposes. These procedures reflect the perspective of consultation agencies that deviate from the nature of risk assessment and demand specific supplementary data that do not reflect familiarity and substantial equilibrium. Based on frequent instances of unintentional environmental release of LMO crops imported into Korea, the ministries responsible for consultation insist on a review that considers the climate and natural environment of Korea. In addition, the ministries mandate that their reviews reflect the expertise of competent ministries and are based on risk assessment principles and methods in accordance with international guidelines. In this regard, considering that traits introduced into LMO crops involving familiar agricultural crops have been considered safe for more than two decades, we have suggested reasonable alternatives to several risk assessment items for agricultural LMOs. These alternatives can mitigate conflicts of interest among key stakeholders within the scope of the current LMO regulations.

A study of growth factors, chondrogenic differentiation of mesenchymal stem cells and cell response by needle size differences in vitro (인간간엽줄기세포의 연골세포 분화 유도 성장인자 및 주사침 크기 차이에 따른 세포반응에 대한 in vitro 연구)

  • Jeongyun Park;Yu Jeong Hwang;Joseph Junesirk Choi;Jin Young Chon;Suk Won Lee
    • Journal of Dental Rehabilitation and Applied Science
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    • v.40 no.1
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    • pp.13-23
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    • 2024
  • Purpose: This aim of this study was to demonstrate growth factors that differentiate human mesenchymal stem cells into chondrocytes and to evaluate cell proliferation enhancement by needle size differences. Materials and Methods: Human mesenchymal stem cells were cultured in chondrogenic medium supplemented with BMP-2, BMP-4, BMP-6, BMP-7, BMP-13, FGF-2, FGF-18, IGF-1, TGF-β1, TGF-β2, TGF-β3 and without growth factors for 14, 21, and 28 days. Then, the expression levels of SOX-5, SOX-6, SOX-9 and FOXO1A were comparatively analyzed. Human mesenchymal stem cells were inoculated into culture dishes using 18, 21, and 26 gauge (G) needles, and cell proliferation was measured after 24, 48, and 72 hours, respectively. Results: In addition to the previously known FGF, IGF-1, and TGFβ1,the BMP family growth factors such as BMP-2, BMP-4, BMP-6, and BMP-7 increased the expression of chondrocyte differentiation genes SOX-5, SOX-6, SOX-9, and FOXO1A. At 48 hours, the 26G group, the smallest needle, showed significant cell proliferation improvement compared to the control group and the 18G group. At 72 hours, the 26G group, the smallest needle, showed significant increase in cell proliferation compared to the control group. Conclusion: Through this study, growth factors with the ability to induce chondrocyte differentiation of human mesenchymal stem cells were investigated, and cell proliferation changes by needle size differences were determined.

Bloom-forming Cyanobacteria in Yongdam Lake (1) Nutrient limitation in a Laboratory Strain of a Nitrogen-fixing Cyanobacterium, Anabaena spiroides v. crassa (용담호 녹조현상의 원인 남세균 연구 (1) 질소고정 남세균 Anabaena spiroides v. crassa 종주와 영양염 제한)

  • Park, Jong-Woo;Kim, Young-Geel;Heo, Woo-Myung;Kim, Bom-Chul;Yih, Won-Ho
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.11 no.4
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    • pp.158-164
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    • 2006
  • Yongdam Lake is the fifth largest artificial lake in Korea newly formed by the first impounding the Yongdam Multi-purpose Dam on December, 2002. Yongdam Lake, with her total water storage of 820 million M/T, is located at the roof-top region of the streams flowing into the just-constructed new Saemankeum Lake. Seasonal succession of phytoplakton in Yongdam Lake might affect cyanobacterial blooms in Saemankeum Lake by inoculating seasonal dominants. During 2002-2003 when the first impounding after the construction of Yongdam Multi-purpose Dam was still undergoing, summer cyanobacterial blooms by Anabaena, Microcystis, and Aphanizomenon were observed. Among these three, filamentous Anabaena is well known to have its species with $N_2-fixing$ ability and special cells such as heterocysts and akinetes as well as the vegetative cells. We established a clonal culture of Anabaena spiroides v. crasse (KNU-YD0310) from the live water samples collected at the bloom site of Yongdam Lake. The N- and P-nutrient requirement of the KNU-YD0310 was explored by the experimental cultivation of the laboratory strain. Ratio of heterocysts to vegetative cells increased as N-deficiency extended with its maximum at $N_2-fixing$ condition. The strain KNU-YD0310 exhibited considerable growth under N-limiting conditions while its growth was proportional to the initial phosphate-P concentration under P-deficient conditions. Under P-limiting conditions akinete density increased, which could be interpreted as an adaptation strategy to survive severe environment by transforming into resting stage. The above eco-physiological characteristics of Anabaena spiroides v. crassa might be useful as an ecological criterion in controlling cyanobacterial blooms at Shaemankeum Lake in near future.

The Effect of the Gap between College Students' Perception of the Importance of Coffee Shops and Their Satisfaction after Patronizing Coffee Shops on Their Purchasing Behavior (대전원교학생대가배점중요성적감지화타문광고가배점지후적만의도지간적차거대타문구매행위적영향(大专院校学生对咖啡店重要性的感知和他们光顾咖啡店之后的满意度之间的差距对他们购买行为的影响))

  • Lee, Won-Ok
    • Journal of Global Scholars of Marketing Science
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    • v.19 no.4
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    • pp.1-10
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    • 2009
  • The purpose of this study was to categorize the gap between coffee shop 'importance' (as perceived by customers before patronizing the coffee shop) and 'satisfaction' (perception of customers after patronizing the coffee shop) as positive or negative and to analyze the effect of these gaps on purchasing behavior. To do this, I used the gap between importance and satisfaction regarding the choice of a coffee shop as the explanatory variable and performed an empirical analysis of the direction and size of the effect of the gap on purchasing behavior (overall satisfaction, willingness-to-revisit) by applying the Ordered Probit Model (OPM). A previous study that used IPA to evaluate the effects of gaps estimated the direction and size of a quadrant but failed to analyze the effect of gaps on customers. In this study, I evaluated the effects of positive and negative gaps on customer satisfaction and willingness-to-revisit. Using OPM, I quantified the effect of positive and negative gaps on overall customer satisfaction and willingness-to-revisit. Per-head expenditure, frequency of visits, and coffee-purchasing place had the most positive effects on overall customer satisfaction. Frequency of visits, followed by per-head expenditure and then coffee-purchasing place, had the most positive impact on willingness-to-visit. Thus per-head expenditure and frequency of visits had the greatest positive effects on overall satisfaction and willingness-to-revisit. This finding implies that the higher the actual satisfaction (gap) of customers who spend KRW5,000 or more once or more per week at coffee shops is, the higher their overall satisfaction and willingness-to-revisit are. Despite the fact that economical efficiency had a significant effect on overall satisfaction and willingness-to-revisit, college and university students still use coffee shops and are willing to spend KRW5,000 because they do not only purchase coffee as a product itself, but use the coffee shop for other activities, such as working, meeting friends, or relaxing. College and university students also access the Internet in coffee shops via personal laptops, watch movies, and study; thus, coffee shops should provide their customers with the appropriate facilities and services. The fact that a positive gap for coffee shop brand had a positive effect on willingness-to-revisit implies that the higher the level of customer satisfaction, the greater the willingness-to-revisit. A negative gap for this factor, on the other hand, implies that the lower the level of customer satisfaction, the lower the willingness-to-revisit. Thus, the brand factor has a comparatively greater effect on satisfaction than the other factors evaluated in this study. Given that the domestic coffee culture is becoming more upscale and college/university students are sensitive to this trend, students are attentive to brands. In most upscale coffee shops in Korea, the outer wall is built out of glass that can be opened, the interiors are exotic with an open kitchen. These upscale coffee shops function as landmarks and match the taste of college/university students. Coffee shops in Korea have become a cultural brand. To make customers feel that coffee shops are upscale, good quality establishments and measures to provide better services in terms of brand factor should be instituted. The intensified competition among coffee shop brands in Korea as a result of the booming industry indicates that provision of additional services is needed to differentiate competitors. These customers can also use a scanner free of charge. Another strategy that can be used to boost brands could be to provide and operate a seminar room for seminars and group study. If coffee shops adopt these types of strategies, college/university students would be more likely to consider the expenses they incur worthwhile and, subsequently, they would be more likely to be satisfied with the brands of these coffee shops, with an associated increase in their willingness-to-revisit. Gender and study year had the most negative effects on overall satisfaction and willingness-to-revisit. Female students were more likely to be satisfied and be willing to return than male students, and third and fourth-year students were more likely to be satisfied and willing-to-return than first or second-year students. Students who drink coffee, read books, and use laptops alone at coffee shops are easily noticeable. High-grade students tend to visit coffee shops alone in order to use their time efficiently for self-development and to find jobs. The economical efficiency factor had the greatest effect on overall satisfaction and willingness-to-revisit in terms of a positive gap. The higher the actual satisfaction (gap) of students with the price of the coffee, the greater their overall satisfaction and willingness-to-revisit. Economical efficiency with a negative gap had a negative effect on willingness-to-revisit, which implies that a less negative gap will result in a greater willingness-to-revisit. Amid worsening market conditions, coffee shops located around colleges/universities are using strategies, such as a point or membership card, strategic alliances with credit-card companies, development of a set menu or seasonal menu, and free coffee-shot services to increase their competitive edge. Product power also had a negative effect in terms of a negative gap, which indicates that a higher negative gap will result in a lower willingness-to-revisit. Because there are many more customers that enjoy coffee in this decade, as compared to previous decades, the new generation of customers, namely college/university students, want various menu items in addition to coffee, and coffee shops should, therefore, add side menu items, such as waffles, rice cakes, cakes, sandwiches, and salads. For example, Starbucks Korea is making efforts to enhance product power by selling rice cakes flavored in strawberry, wormwood, and pumpkin, and providing coffee or cream free of charge. In summary, coffee shops should focus on increasing their economical efficiency, brand, and product power to enhance the satisfaction of college/university students. Because shops adjacent to colleges or universities enjoy a locational advantage, providing differentiated services in terms of economical efficiency, brand, and product power, is likely to increase customer satisfaction and return visits. Coffee shop brands should, therefore, be innovative and embrace change to meet their customers' desires. Because this study only targeted college/university students in Seoul, comparative studies targeting diverse regions and age groups are required to generalize the findings and recommendations of this study.

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Effects of Planting Date and Density on Yield and It’s Components of Fritillaria thungergii MIQUEL (패모(貝母)의 파종기(播種期) 및 재식밀도(栽植密度)가 수양구성(收量構成) 형질(形質) 및 수양(收量)에 미치는 영향(影響))

  • Choi, In-Sik;Cho, Jin-Tae;Son, Seok-Yong;Park, Jae-Seong;Han, Dong-Ho;Jeong, In-Myeong
    • Korean Journal of Medicinal Crop Science
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    • v.4 no.3
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    • pp.218-223
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    • 1996
  • This experiment was carried out to investigate the effect of planting date and planting density on yield and yield components of Fritillariae bulbus from 1989 to 1991. The Chungbuk local variety was used, and the experimental materials were planted six times with 10 days interval from Aug. 20 to Oct. 10. 33, 22, 17 and 13 bulbs were planted by the square meter, respectively. The compound fertilizer for garlic $(N\;-\;P_2O\;-\;K_2O_5=9\;-\;14\;-\;10)$ was applied by 80kgs to the 0.1ha before planting. The experimental design was randomized block design with 3 replications. As the planting dates were earlier, the emerging dates were earlier, too. But the delay of 50 days in the planting affected to the delay of 14 days in the em­erging dates. The plant height was 22.7cms in the Aug. 20 plot. As the planting were later, the plant heights were shorter by $2.4{\sim}5.6cms$ than that. As compared with the 829kgs by the 0.1ha of Aug. 30 plot, the others recorded 1 percent increase in the Aug. 20 plot, 4 percent decrease in the Sep. 10 plot, 26 percent decrease in the Sep. 20 plot, 35 percent decrease in the Sep 30 plot, and 38 percent decrease in the Oct. 10 plot. So, the suitable planting dates were from Aug. 20 to Aug. 30.The emerging date of 33 bulb plot by the square meter was March 7, but as the planting densities were sparse, the emerging dates delayed by one to three days. The plant height of the 33 bulb plot by the square meter was 21. 8cms, but the other plots were short by $0.7{\sim}1.8cms$. The number of shoots of the 33 bulb plot by the square meter was 6.1. but the other plots recorded 0.4 increase in the 22 bulb plot, 0.6 increase in the 17 bulb plot and 0.5 increase in the 13 bulb plot compared with that of the 33 bulb plot. Accordingly, the number of shoots in the sparse planting plot was more than that in the dense planting plot. As compared with the 854kgs by the 0.1ha of the 22 bulb plot, the other plots recored 2 percent in­crease in the 33 bulb plot, 16 percent decrease in the 17 bulb plot and 34 percent decrease in the 13 bulb plot. All things considered, for the culture of Fritillaria thungergii MIQUEL in the middle region, Aug. 25 and 22 bulbs by the square meter were suitable for the planting date and density.

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Operation and Perception on Dietary Life Education and Nutrition Counseling of Elementary School in Chungbuk Province (충북지역 초등학교 영양교사의 식생활 교육과 영양상담 운영실태 및 인식)

  • Kim, Myoung-Sil;Kim, Hye Jin;Lee, Young Eun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.12
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    • pp.2049-2067
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    • 2013
  • The purpose of this study is to present a more effective nutrition education activation plan. As a result of investigating the dietary education operating situation, 58.9% underwent direct education, and 89.5% underwent food life education through traditional food culture succeeding business operation. The results from investigating the recognition regarding dietary education are as follows. The activation level by education types was as low as 2.24 points, the necessity was as high as 4.54 points, the difficult point in performing food life education was 'overwork' with 4.43 points, and the teaching activity ability level was 'can effectively prepare a teaching guidance plan' at 2.96 points. As a result of investigating the nutrition consultation operating situations, 62.8% underwent it and all of the students as well as some parents and teachers performed it. The consumed time per consultation for effective nutrition consultation was 10~20 minutes, the required education equipment and data were 'consultation program' with 40.3%, and the important content during consultation was 'contents related to eating habits' with 70.5%, which was recognized as the most important.

Meteorological Constraints and Countermeasures in Rice Breeding -Breeding for cold tolerance- (기상재해와 수도육종상의 대책 - 내냉성품종육성방안-)

  • Mun-Hue Heu;Young-Soo Han
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.27 no.4
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    • pp.371-384
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    • 1982
  • Highly cold tolerant varieties are requested not only at high latitute cool area but also tropical high elevated areas, and the required tolerance is different from location to location. IRRI identified 6 different types of cold tolerance required in the world for breeding purpose; a) Hokkaido type, b) Suweon type, c) Taipei 1st season type, d) Taipei 2nd season type, e) Tropical alpine type and, f) Bangladesh type. The cold tolerance requested in Korea is more eargent in Tongil group cultivars and their required tolerance is the one such as the physiological activities at low temperature are as active as in Japonica group cultivars at least during young seedling stage and reproduction stage. With conventional Japonica cultivars, such cold tolerant characters are requested as short growth duration but stable basic vegetative growth, less sensitive to high temperature and less prolonged growth duration at low temperature. The methods screening for cold tolerance were developed rapidly after the Tongil cultivar was reliesed. The facilities of screening for cold tolerance, such as, low temperature incubator, cold water tank, growth cabinet, phytotron, cold water nursery in Chuncheon, breeding nursery located in Jinbu, Unbong and Youngduk, are well established. Foreign facilities such as, cold water tank with the rapid generation advancement facilities, cold nurseries located in Banaue, Kathmandu and Kashimir may be available for the screening of some limitted breeding materials. For the reference, screening methods applied at different growth stages in Japan are introduced. The component characters of cold tolerance are not well identified, but the varietal differences in a) germinability, b) young seedling growth, c) rooting, d) tillering, e) discolation, f) nutrition uptake, g) photosynthesis rate, h) delay in heading, i) pollen sterility, and j) grain fertility at low temperature are reported to be distinguishable. Relationships among those traits are not consistent. Reported studies on the inheritance of cold tolerance are summarized. Four or more genes are controlling low temperature germinability, one or several genes are controlling seedling tolerance, and four or more genes are responsible for the pollen fertility of the rice treated with cold air or grown in the cold water nursery. But most of those data indicate that the results may come out in different way if those were tested at different temperature. Many cold tolerant parents among Japonicas, Indicas and Javanicas were identified as the results of the improvement of cold tolerance screening techniques and IRTP efforts and they are ready to be utilized. Considering a) diversification of germ plasm, b) integration of resistances to diseases and insects, c) identification of adaptability of recommending cultivars and, d) systematic control of recommending cultivars, breeding strategies for short term and long term are suggested. For short term, efforts will be concentrated mainly to the conventional cultivar group. Domestic cultivars will be used as foundation stock and ecologically different foreign introductions such as from Hokkaido, China or from Taiwan, will be used as cross parents for the adjustment of growth durations and synthsize the prototype of tolerances. While at the other side, extreme early waxy Japonicas will be crossed with the Indica parents which are identified for their resistances to the diseases and insects. Through the back corsses to waxy Japonicas, those Indica resistances will be transfered to the Japonicas and these will be utilized to the crosses for the improvement of resistances of prototype. For the long term, efforts will be payed to synthsize all the available tolerances identified any from Japonicas, Indicas and Javanicas to diversify the germ plasm. The tolerant cultivars newly synthsized, should be stable and affected minimum. to the low temperature at all the growing stages. The resistances to the diseases and insects should be integrated also. The rapid generation advancement, pollen culture and international cooperations were emphasized to maximize the breeding efficiency.

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Studies on absorption of ammonium, nitrate-and urea-N by Jinheung and Tongil rice using labelled nitrogen (중질소(重窒素)를 이용(利用)한 진흥(振興)과 통일(統一)벼의 암모니움, 질산(窒酸) 및 요소태(尿素態) 질소(窒素)의 흡수특성(吸收特性) 연구(硏究))

  • Park, Hoon;Seok, Sun Jong
    • Korean Journal of Soil Science and Fertilizer
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    • v.10 no.4
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    • pp.225-233
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    • 1978
  • Uptake and distribution of labelled urea, $NH{_4}^+$, and $NO{_3}^-$ by Tongil and Jinheung rice grown with each nitrogen source until ear formation stage under water culture system were as follows. 1. When the previous nitrogen source was same as one tested the uptake rate ($mg^{15}N/g$ d.w. root 2hrs, at $28^{\circ}C$ light) was great in the order of $NH_4$ >urea> $NO_3$ and higher (especially $NH_4$) in Tongil than in Jinheung. Rate limiting step (slowest) seems to be exist at R (root)${\rightarrow}$LS(leaf sheath) for urea, LS${\rightarrow}$LB(leaf blade) for $NH_4$ and M(medium)${\rightarrow}$R for $NO_3$. The fast step of translocation appeare to be at M${\rightarrow}$R for urea R${\rightarrow}$LS for $NH_4$ and LS${\rightarrow}$LB for $NO_3$. 2. The uptake rate of $NH_4$ by the urea-fed plant increased almost linearly from $18^{\circ}C$ via $28^{\circ}C$ to $38^{\circ}C$ in Tongil ($Q_{10}$=1.21 and 1.32 respectively) while no change in Jinheung ($Q_{10}$=0.99 and 1.00 respectively). It decreased by 12% in Jinheung under dark but uo change in Tongil. 3. The uptake rate of nitrogen source by different source-fed plant was great in the order of $NH_4{\rightarrow}^{15}NO_3$ $NO_3{\rightarrow}^{15}NH_4$, $urea{\rightarrow}^{15}NO_3$ and higher (especially $NH_4{\rightarrow}^{15}NO_3$) in Tongil. In the case of $urea{\rightarrow}^{15}NH_4$ it was same in $NH_4{\rightarrow}^{15}NO_3$ for Tongil and slightly lower than that in $NO_3{\rightarrow}^{15}NH_4$ for Jinheung. It was lower (especially Tongil) in $NH_4{\rightarrow}^{15}NO_3$ than in $NH_4{\rightarrow}^{15}NH_4 $ 4. The uptake rate (in $NH_4{\rightarrow}^{15}NO_3$) was higher during 15 minutes than during 2 hours and always higher in Tongil. 5. $^{15}N$ excess % and content in each part, and uptake rate of root seems to have their own significance relatling with metabolism and translocation respectively. The change of nitrogen nutritional environment and source preference of varieties were discussed in relation to field condition and efficient use of nitrogen fertilizer.

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Effect of Several Herbicides in the Polyethylene - film Mulched Young Mulberry Field (P.E. 필름피복(被覆) 밀식(密植) 뽕밭에서의 수종(數種) 제초제(除草劑) 처리효과(處理效果))

  • Kim, Ho-Rak;Kwon, Yong-Woong;Cho, Yong-Woo
    • Korean Journal of Weed Science
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    • v.5 no.2
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    • pp.202-210
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    • 1985
  • Requirements in weed control in a mulberry field are much similar to those in orchards, but also feature a longer period of weed control of various kinds of persistent weeds, i.e., spring, summer, and winter annuals as well as perennials. In addition the mulberry tree is relatively more sensitive to herbicide injury. Hence, very few herbicides have been used in mulberry field. The present study was conducted to evaluate the usefulness of oxyfluorfen in comparison with alachlor and simazine, which are registered for ordinary mulberry field in Korea, for weed control efficacy in the new, rapidly increasing practice of transparent polyethylene-film mulched and densely planted younger mulberry culture. Dominant spring weeds were Galium spp., Erigeron spp., Polygonum senticosum, and Chenopodium spp. in the non-mulched interbed area in contrast to the Digitaria spp. and Potulaca spp, under mulch. Dominant summer weeds were Digitaria spp., Portulaca spp., Erigeron spp., Artemisia spp. and Calystegia japonica in the non-mulched interbed area while weeds did not occur significantly during summer under mulch which were shaded by vigorously growing mulberry trees. The weeds occurred under mulch in spring reduced shoot growth of young mulberry tree resulting in the reduced yield of mulberry leaves for silkworms. The weeds occurred in the interbed area did not affect until May, but interfered later summer- and fall-growth of mulberry tree. Early single spring application of alachlor(EC), simazine(WP) or oxyfluorfen(EC) at a rate of 650 g, 750 g or 350 g ai per ha, respectively, controlled most annuals satisfactorily to fall in the mulched bed area. In the nonmulched interbed area, however, thrice does of alchlor or simazine was necessary for satisfactory control of spring weeds, followed by summer application of alachlor or simazine at twice dose level as tank mixture with paraquat at 490 g ai per ha for satisfactory control of summer to fall weeds. Single spring application of oxyfluorfen at a rate of 1400 g ai per ha was persistently effective to control satisfactorily even summer and fall weeds. However, heavy rainfall splashed soil borne oxyfluorfen to the lower branch leaves causing some leaf burns. Spring application of oxyfluorfen at a rate of 350 g ai per ha followed by summer application of oxyfluorfen and paraquat tank mixture (350 g ai + 490 g ai) was the best choice for the non-mulched interbed area weed control among the treatments.

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