• Korean Journal of Breeding Science
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• v.41 no.3
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• pp.252-260
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• 2009

Rice is the most important cereal crop not only in supplying the basic staple food for more than half of the world's population but also as a model plant for functional genomic studies of monocotyledons. Although rice transformation method using A. tumefaciens has already been widely used to generate transgenic plants, the transformation rate is still low in most Korean elite cultivars. We made several modifications of the standard protocol especially in the co-cultivation step to improve the efficiency of the rice transformation. The co-culture medium was modified by the addition of three antioxidant compounds (10.5 mg/L L-cysteine, 1 mM sodium thiosulfate, 1 mM dithiothreitol) and of Agrobacterium growth-inhibiting agent (5 mg/L silver nitrate). Co-cultivation temperature ($23.5^{\circ}C$ for 1 day, $26.5^{\circ}C$ for 6 days) and duration (7 days) were also changed. The plasmid of pMJC-GB-GUS carrying the GUS reporter gene and the bar gene as the selectable marker was used to evaluate the efficiency of the transformation. After co-cultivation, a high level of GUS gene expression was observed in calli treated with the modified method. It is likely that those newly added compounds helped to minimize the damage due to oxidative bursts during plant cell-Agrobacterium interaction and to prevent necrosis of rice cells. And the transformation rate under the modified method was also remarkably increased approximately 8-fold in Heungnambyeo and 2-fold in Ilmibyeo as compared to the corresponding standard method. Furthermore, we could produce the transgenic plants stably from Ilpumbyeo which is a high-quality rice but its transformation rate is extremely low. Transformation and the copy number of transgenes were confirmed by PCR, bar strip and Southern blot analysis. The improved method would attribute reducing the effort and the time required to produce a large number of transgenic rice plants.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.2
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• pp.103-111
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• 2008

This study was carried out to investigate the optimal application rate and time of mixed expeller cake (MEC) for the replacement of chemical fertilizer. Dongjin-1, as cultivated rice was used at Fluvio-marine deposit in Honam plain paddy field. Soil chemical properties were improved by the application of MEC. Contents of total nitrogen and organic matter were higher in 70%, 100% plots of basal dressing than standard fertilizer application (SFA) plot. Cation exchangeable capacity was highly increased in 70% plot of basal dressing. Also, the content of organic matter in soil was increased with MEC application. Cation exchangeable capacity, total nitrogen and available phosphate were decreased according to late application time. The content of inorganic nitrogen in soil showed high tendency at more application rate of MEC, and nitrogen mineralization at harvest season have finished in 50%, 70% plots of basal dressing. The content of inorganic nitrogen in soil was increased according to late application time, however it was decreased in the late period of growth. Leaf color value became darker with increased application rate of MEC. Leaf color was dark green in MEC application plots at panicle formation stage, on the other hand, it was light green in 50%, 70% plots of basal dressing at heading stage. SPAD reading value of leaf-color was high during the whole growth stage in MEC application plots. More application rate of MEC showed higher tendency of fertilizer nitrogen absorption. Nitrogen use efficiency was the highest in 70% plot of basal dressing. Absorbed amount of fertilized nitrogen was increased in 10~15days before transplanting and nitrogen use efficiency was high according to the late application time. The ratio of perfect kernel and the content of protein on hulled rice showed high tendency at the less application rate of MEC. The ratio of head rice on milled rice showed high tendency at the less application rate of MEC. Rice yield increased 4% in 100% and 70% plots of basal dressing compare with SFA ($5.18Mg\;ha^{-1}$) plot respectively. Ear and culm length of rice were long according to the late application time, while the numbers of spikelet and ear were increased and the percentage of ripened grain was decreased. Rice yield was increased 2~5% in all MEC application plots compared to SFA plot and especially, increased 10~15days before transplanting in application plots. The optimal application rate and time of MEC on normal paddy field in plain were concluded that 70% basal dressing and 10~15days before transplanting

• Journal of Environmental Health Sciences
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• v.21 no.1
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• pp.56-67
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• 1995

This study was carried out to observe how composting reaction proceed in the optimum composting condition and to understand the characteristics of final compost, when swine feces was amended with different bulking material. Sawdust, rice straw, and rice hull were selected as bulking materials and each of these was mixed with swine feces to obtain the optimum range of moisture contents and C:N ratio. To grasp the influence of newspaper on cornposting reaction when it flew into the composting site intentionally or accidentally, another composting reaction using newspaper as a bulking material was studied. In this experiment, raw material mixes containing the same amount of organic materials were put into 4 composting reactors and composted in the same environmental condition for 3 weeks from Aug. 1, 1994 to Aug. 22, 1994. The followings are the main results of this study. 1. The maximum temperatures reached at during cornposting reaction were 53.8$\circ$C, 51.9$\circ$C, 52.7$\circ$C, and 52.1$\circ$C in the reactor using sawdust, rice straw, rice hull, and newspaper as a bulking material respectively: Thermophilic temperatures were maintained for 72, 108, 108, and 111 hours in each reactor. Mean temperatures of reactors using sawdust, rice straw, rice hull, or newspaper as a bulking materials were 39.7$\circ$C, 39.5$\circ$C, 41.3$\circ$C, and 40.3$\circ$C, but no significant difference between these mean temperatures was observed(p>0.05). Each composter showed significant difference from room temperature(p<0.01), and the mean difference between them was 9.4$\circ$C. 2. Ash contents of each reactor increased rapidly in order of rice straw, rice hull, newspaper, and sawdust according to the pattern of second order function. This rate of increase seemed to result from structural characteristics of a bulking material. The absolute values of second order coefficient of these regression functions were 0.0199, 0.0159, 0.0157, and 0.0144 in each reactor using rice straw, rice hull, newspaper, or sawdust as a bulking material. 3. C:N ratio decreased as the reaction proceeded. Degree of decrease was in order of rice straw, rice hull, newspaper, and sawdust. This sequence was consistent with the increase rate of ash content. The ratios of initial C:N ratio to final C:N ratio were 0.45, 0.53, 0.64, and 0.75 in each reactor using rice straw, rice hull, newspaper, and sawdust as a bulking material respectively. From this ratios, it was possible to infer that all the composting reactions were completed. 4. Fertilizer content containing in the final compost was 1.61~2.20% of N, and 0.35~0.54% of P in dry weight base. According to the classification standard for compost constituent by Higgins, all composts had the intermediate grade of N, but below the low grade of P excepting the newspaper amended compost(fall into the range of the low grade). 5. Heavy metal contents contained in the composts were analyzed. In case of Cd, the range of 0.58~1.11 $\mu$g/g was observed, and in case of Pb, the range of 24.76~39.53 $\mu$g/g was observed(in wet weight base). These values are below the permissible heavy metal level for compost of foreign countries.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.492-501
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• 2016

This study was conducted to investigate the physiochemical characteristics of Cheongju prepared using different types of rice (rice and glutinous rice) according to addition rate of Nuruk during low temperature fermentation. The characteristics of Cheongju prepared using three different temperatures ($10^{\circ}C$, $18^{\circ}C$, $25^{\circ}C$) were compared. After fermentation for 30-50 days, the pH of mash prepared at lower temperature was lower, as was that of mash made from rice relative to that prepared using glutinous rice. The total acidity was formed at lower temperature and generated in mashing prepared by glutinous rice. The organic acid content of mash made from rice at $18^{\circ}C$ was lowest, while that of mash prepared from glutinous rice was lowest at $10^{\circ}C$. The fermentation speed was lowest at $10^{\circ}C$; however, low temperature fermentation resulted in the highest alcohol content. The mash prepared from glutinous rice showed faster fermentation than that made from rice. In addition, the pH was lower when lower levels of Nuruk were added and higher in mash made from glutinous rice than that prepared from rice. The lower addition rate of Nuruk also showed a lower sugar content and final alcohol content. The levels of citric acid and lactic acid were higher, while those of succinic acid, acetic acid, and ethyl acetate were lower when lower levels of Nuruk were added. The mash prepared from glutinous rice showed a higher alcohol content than that made from rice.

• Journal of the Korean Home Economics Association
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• v.41 no.3
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• pp.181-196
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• 2003

Investigated kinds and utilization frequency for traditional food and Particular food to systematize Gwangju city and Chollanamdo area traditional food culture. Awareness for traditional food had pride because taste is various, and did that must use much when was festive day. Investigation subject were feeling necessity about accession, development of traditional food, and manufacture of traditional food, succession did that must take charge in home. Characteristic of taste for Gwangju city, Chollanamdo food was deep taste. Difference between variable was significant that age, religion that have pride about traditional food, attainments in scholarship, monthly income that used time much traditional food, degree that give from traditional food to snack is age, attainments in scholarship, years of married life, religion, reason that give snack to traditional food is daughter-in-law order, kind of traditional food that give to snack is age, monthly income mouth, opinion about accession and development of traditional food is age, religion, daughter-in-law order, reason that must inherit and develop traditional food is attainments in scholarship, time that eat much traditional food is attainments in scholarship, a person, medium that learn cuisine of traditional food is age, opportunity that is been interested to traditional food is age, attainments in scholarship, years of married life. By utilization rate of food-tasting food subdivisions of the season, used much by rice-cake soup, fermented rice punch, order of cake made from glutinous rice New Year's Day, by herbs, Gimgui, Ogokbap's order January Full Moon Day on the lunar calendar. By a cake made in the shape of a flower, azalea honeyed juice mixed with fruits as a punch order to Samjitnal, by beans panbroiling, dropwort raw order Buddha's Birthday, Tano Festival uses Charyunbyeong and used Tteoksudan in Yudu and used much by young chicken soup with ginseng and other fruits, watermelon order period of midsummer heat. Used songpyon and fermented rice punch in Full-moon Harvest Day, and Junggujeol used Chrysanthemum griddle cakes made in flower Pattern, and red-bean gruel taken on the winter solstice, and Nappyeongjeolsik was utilizing Goldongban. Pyebaek food utilization ratio was high the utilization rate by chestnut, jujube, chicken, wine order. The contributiveness food utilization rate was high the utilization rate by rice cake, dried croaker, fruit, oil-and-honey pastry order. The large table food utilization rate was high the utilization rate by fermented rice punch, fruit, steamed short-ribs order.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2000.11a
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• pp.55-60
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• 2000

The effects of improved rice bran oil on the characteristics of exhaust emissions have been experimentally examined by a single cylinder, four cycle, direct injection, water-cooled and agricultural diesel engine operating at several loads and speeds. The experiments are conducted with light oil rice bran oil, and improved rice bran oil as a fuel. The fuel injection timing is fixed to 22$^{\circ}$BTDC regardless of fuel type, engine loads and speeds. To reduce the viscosity of rice bran oil, it is used with the methods of heating, methyl ester and ultrasonic system in a highly viscous rice bran oil. In this study, it is found that the brake specific fuel consumption rate of light oil is the lowest and that of improved rice bran oil is lower than that of pure rice bran oil, and NOx emissions of light oil are the lowest and those of pure rice bran oil are the highest, but soot emissions of light oil are the highest. However these results are not amply satisfied with the emissions regulation limit using the pure and improved rice bran oil as a fuel in diesel engines.

• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.1
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• pp.55-70
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• 2001

It was unusual crop weather for 1998 and 1999 compared with normal in Korea. The consecutive days of the optimum ripening period for rice plant that had daily mean temperature 21~23$^{\circ}C$ for 40 days after flowering, increased with long anomalies in 1998~99. The air temperature during ripening period was much higher than the optimum temperature and lower sunshine hour than norm in the local adaptability tests of newly developed rice lines during those years. In response of rice cultivation to warming and cloudy weather during crop season, the yield shall be decreased. Most scientists agree that the rate of heating is accelerating and temperature change could become increasingly disruptive. Weather patterns should also become more erratic. Agrometeorologists could be analyzed yearly variations of temperature, sunshine hour and rainfall pattern focused on transient agroclimate change for last a decade. Rice agronomists could be established taking advantage of real time agricultural meteorology information system for fertilization, irrigation, pest control and harvest. Also they could be analyzed the characteristics of flowering response of the recommended and newly bred rice cultivars for suitable cropping plan such as cultural patterns and sowing or transplanting date. Rice breeders should be deeply considered introducing the characteristics of basic vegetative type of flowering response like Togil rices as prospective rice cultivars corresponding to global warming because of the rices needed higher temperature at ripening stage than japonica rices, photoperiod-sensitive and thermo-sensitive ecotypes.

• Korean Journal of Organic Agriculture
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• v.30 no.2
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• pp.191-206
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• 2022

Rice has prevailed as a staple food in South Korea. Rice consumption has sharply shrunk nowadays. In the wake of COVID-19 Shock and the "untact" era, the instant rice market has significantly grown, and there is a possibility of solving the shrinking consumption of domestic rice. This study contributes to the development of rice consumption promotion strategies by examining the factors of purchasing instant rice based on the Hedonic Price Methodology. In particular, given the increase in online market, this study compares attribute values of product characteristics between online and offline markets. The empirical results show that calorie, brand, organic and functional products have positive effects on instant rice prices. The rate of carbohydrate, the PB and bundle attributes have negative effects on instant rice prices. The results also show that the magnitude of brand, bundle and PB attribute values are bigger in offline market while that of the number of multigrain attribute value is relatively bigger in online market. The organic attribute value is important regardless of marketing channels.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.3
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• pp.270-277
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• 1994

This study was conducted to investigate change of seed dormancy during storage in rice. The result of germination rate observed at different storage duration after harvest indicated that two Japonica rice varieties, Sangpungbyeo and Hwaseongbyeo, tow sare type local varieties, Jakwangdo and Mongeunsare, and a Tongil type rice, Samgangbyeo, showed no dormancy in rice seed harvested at 40 days after heading, However, weak dormancy was found in matured rice seed of Sobaekbyeo and Odaebyeo, and strong seed dormancy was found in Jungwonbyeo, IR-20 and IR-42. Rice seed stored for 30 days after harvest at 2$0^{\circ}C$ constant temperature or 25/15$^{\circ}C$ of day /night temperature fluctuation showed higher germination rate above 90% in all varieties tested. But germination rate of seeds stored at 4$^{\circ}C$ for 30 to 180 days showed varietal difference, higher in rice varieties having weak seed dormancy and lower in strong dormancy varieties. Days to 80% germination and average days for germination were shortened by storage for 30 to 180 days after harvest at 2$0^{\circ}C$, 4$^{\circ}C$ with RH 40% or day /night 25/15$^{\circ}C$ temperature condition in all rice varieties tested, but the degree of acceleration was lower at the condition of 4$^{\circ}C$ with RH 40%.

• Food Science and Preservation
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• v.24 no.6
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• pp.758-763
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• 2017

In this study the effect of rice addition on the quality of beer was investigated. Pilot-scale brews were performed with addition ratios of 10, 20, 30, and 40% of brown rice (Oryza sativa L. cv. Hangaru) which were compared with 100% malt beer and commercial beers in terms of quality. Alcohol content of beer was between 3.93 to 4.40%. The total sugar content increased when the rice percent was increased. The pH range of beer were 4.32 and 4.60, which were no significant differences found among by the rate of rice added. Total acidity and amino-acidity decreased corresponding to increasing percent of rice, on the other hand, lightness of beer was increased the increase in percent of rice, while redness and yellowness of beer were decreased. The study demonstrated that the increases of rice addition in beer provided some positive effects on beer quality by decreasing bitterness where as improving beer color.