• Journal of the East Asian Society of Dietary Life
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• v.27 no.2
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• pp.159-167
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• 2017

In this study, quality characteristics of yakju fermented with byeo-nuruk prepared using rice, wheat, and water were investigated. Five different mixture ratios were considered for byeo-nuruk preparation. A comparative analysis of commercial yakju and byeo-nuruk yakju was also performed. The results showed no significant differences in pH, total acidity, and total soluble solids of byeo-nuruk yakju immediately following fermentation. The byeo-nuruk yakju alcohol content increased with increasing wheat proportion. Lactic and succinic acid were the major organic acids of byeo-nuruk yakju, and the major volatile components were isoamyl alcohol and linalool. Yakju prepared using material D had the highest volatile component content and high preference evaluation scores for taste and overall acceptability. Compared to commercial yakju, byeo-nuruk yakju had less total acidity, soluble solids, and volatile acids, whereas its pH level and amino acid content were higher. No significant differences were observed between commercial yakju and byeo-nuruk yakju in terms of sensory evaluation.

• Journal of Biosystems Engineering
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• v.27 no.2
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• pp.125-132
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• 2002

In order to investigate the optimum moisture content of paddy for milling process, a series of tests were conducted by examining the recovery rate and whiteness of milled rice in relation with the various moisture content. Hwabong-byeo and Dongjin-byeo varieties which were major paddies cultivated in Korea were used for the experiment. The test was performed with small experimental milling machines. In order to minimize the unexpected factors, environment conditions were kept in constant during the experiment. As a result, the recovery rate of milled rice were varied as the changes in milling time and degree of whiteness. However, the recovery rate of milled rice increases as its moisture content increases untill a certain point of moisture content and decreases slowly afterward. This certain point can be called optimum moisture content for rice milling. Also, it has a different value depending on the variety. In this experiment, optimum moisture content of Hwabong-byeo and Dongjin-byeo were considered around 14.8% and 15.3%, respectively. It is not sure that these optimum moisture contents for the two varieties would assume the same values irrespective of harvest year and place. However, it could be concluded that the optimum moisture content for rice milling is around 15%(w.b.) for Hwabong-byeo and 15.5%(w.b.) for Dongjin-byeo, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.3
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• pp.255-262
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• 1997

To estimate the total dry matter(TDM) of rice plant by non-destructive method, spectral reflectance from rice plant canopy was measured by using the spectroradiometer (LI-1800, LICOR Inc.) with one week interval during the rice growing season at Suwon paddy field in 1993. Two medium late maturing rices, Daechung-byeo Ilpum-byeo, and one early maturing variety, Jinbu-byeo, were cultured to observe TDM, then they were compared with those estimated by vegetation index together. Vegetation index determined by the reflectance of visible against near infrared wavelength showed high correlation with TDM. Vegetation index derived from narrow band(10nm interval) ratio, R910/R460, has the highest correlation coefficient with TDM. TDM estimated from R910/R460 from transplanting to heading stage corresponded well to measured values (Y=21.2428X-212.734 ; $R^2$=0.87). But another vegetation index, NIR(720~1,100nm) /Red(600~700nm) showed higher correlation with TDM than NIR(720~1,100nm) /Blue(400~500nm) did from heading stage to maturity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.4
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• pp.305-309
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• 1991

This experiment was conducted to investigate the effect of shattered grain by combine harvesting at the previous year on rice plant emergence at different planting methods and plant characteristics, The results are follows : Combine harvesting greatly influence on shattered grain of Samgangbyeo as Tongil variety (49.5kg/10a) compared to that of Nagdongbyeo as Japonica variety(27.8kg/10a), while Nagdong-byeo showed higher germination rate than Samgangbyeo, whether transplanted and direct seeded. Emergence of volunteer and seed mixture were lower in transplanted than in direct seeded. In variety test. Japonica variety showed higher emergence of volunteer rice and seed mixture than Tongil variety. Generally, no significant difference in yield components were observed with different varieties by the volunteer rice. But the volunteer rice caused by combine harvesting decreased culm length, panicle length, spikelet number, panicle number and ripening ratio. except l000-grain weights.

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.1
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• pp.26-33
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• 1990

The pot experiment was conducted to compare the effects of BIO-COM (Organic fertilizer made from industrial by-product) with the compost and humic acid on the physico-chemical properties of soils and the yield of paddy rice (CV. Chucheong-byeo). The results obtained were as follows: 1. All the fertilizer treatments, except humic acid, increased rice yield compare to no fertilizer treatment, and Bio-Com was the highest among the fertilizer treatments. 2. Rice yields were increased with increasing BIO-COM only up to 4% but 2% with N.P.K. fertilizers. 3. Rice yield showed highly positive correlation with number of panicle per hill but negative correlation with 1000 grain weight. 4. BIO-COM application induced the noticeable increase of pH, EC, OM, T-N, Av-P, Ex-Ca, Ex-Mg, Ex-Na, and $Av-SiO_2$, contents in the soils after experiments, and there were highly significant positive correlation among them. 5. BIO-COM application was positively affected on plant height, number of tiller, and fresh weight and dry weight of rice plant throughout entire growing stages and these are positively correlated with rice yield. 6. BIO-COM application also induced the increase of chlorophyll, N, P, Ca, and Mg contents in rice plant 7. It is revealed that there were highly positive correlations between rice yields and pH, EC, OM, T-N, Ex-Ca, and Ex-Mg in the soils. 8. It was also shown the highly significant positive correlations between rice yields, and N and P contents in the rice plant at heading stages, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.4
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• pp.274-281
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• 2006

In Korea, rice cultivars have been changing to 'quality' rice rather than high yielding cultivars. However, more than 10% of paddy field has been changed to greenhouse in winter season for cropping of water-melon, oriental-melon, straw berry and et cetra. This experiment has been made to identify the usefulness of critical N and Si fertilization(SF) level to obtain high grain quality rice with reduced insect pest damage by N and SF combination. Before the experiment, watermelon-rice cropping system was maintained for three seasons by farmer from 1998 to 2001. The experiment of N and Si (silicate) fertilization levels was evaluated with Hwayoung-byeo (Oryza sativa L., medium-maturing variety) in 2002 and 2003 in Uiryeong, Korea. Nitrogen fertilization (NF) levels were three and five in 2002 and 2003, respectively, and three SF levels were compared for getting the valuable N/SF level in both years. TOYO-value was positively affected by Si application in N100% plot but it was negatively related with NF level. Normal grain percentage was positively related with TOYO-value and it was highest in 0N plot and Si plots in N100%. Other appearance qualities like powdered, damaged, and cracked grain, were decreased with increasing N fertilization level. SF improved appearance quality in N100% plots but no effects in other treatments. Leaf sheath related diseases were significantly decreased by SF but it was negatively related with NF. In conclusion, SF could be improve grain quality at the same yield levels of conventional fertilization and it also could be reduce the diseases damages of rice plant in all N treatments. NF treatment reduced grain quality and improved grain yield at N50% level, however NF above N50% could not get any kind of benefits. So, compared with conventional fertilizer, reduced NF level is recommended for high grain quality with reduced insect pest damage.

• Korean Journal of Environmental Agriculture
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• v.37 no.1
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• pp.15-20
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• 2018

BACKGROUND: The global mean surface temperature change for the period of 2016~2035 relative to 1986~2005 is similar for the four representative concentration pathway (RCP)'s and will likely be in the range of $0.3^{\circ}C$ to $0.7^{\circ}C$. Climate change inducing higher temperature could affect not only crop growth and yield, but also dynamics of carbon in paddy field. METHODS AND RESULTS: This study was conducted to evaluate the effect of elevated temperature on the carbon dynamics in paddy soil and rice growth. In order to control the elevated temperatures, the experiments were set up as the small scale rectangular open top chambers (OTCs) of $1m(width){\times}1m(depth){\times}1m(height)$ (Type 1), $1 m(W){\times}1m(D){\times}1.2m(H)$ (Type 2), and $1m(W){\times}1m(D){\times}1.4m(H)$ (Type 3). The average temperatures of Type 1, Type 2, and Type 3 from July 15 to October 30 were higher than the ambient temperatures at $0.4^{\circ}C$, $0.5^{\circ}C$, and $0.9^{\circ}C$, respectively. For the experiment, Wagner's pots (1/2,000 area) were placed inside chambers. The pots were filled with loamy soil, and chemical fertilizer and organic compost were applied as recommended after soil test. The pots were flooded with agricultural water and rice (Shindongjin-byeo) was planted. It was observed that TOC (total organic carbon) of the water increased by the elevated temperatures and the trend continued until the late growth stage of the rice. Soil TOC contents were reduced by the elevated temperatures. C/N ratios of the rice plant decreased by the elevated temperature treatments. Thus, it was assumed that the elevated temperatures induced to decompose soil organic matter. Elevated temperatures significantly increased the culm length (P<0.01) and culm weight (P<0.05) of rice, but the number and weight of rice panicle did not showed significant differences. CONCLUSION: Based on the results, it was suggested that the elevated temperatures had an effect on changes of soil and water carbons under the possible future climate change environment.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.5
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• pp.354-363
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• 2007

In order to investigate the optimum rate and interval of silicate fertilizer application for rice cultivation, Chucheong byeo variety, one of commonly cultivated rice cultivar in Korea was planted on two different wetland rice soils located on Hwaseong-si from 2002 to 2005; Jisan series(a member of the fine loamy, mixed, mesic family of Fluvaquentic Endoaquepts), known as "Productive Paddy Soil", without any conspicuous limiting factor, and Seokcheon series (a member of the coarse loamy, mixed, nonacid, mesic family of Fluvaquentic Endoaquetps), known as "Sandy Paddy Soil", sandiness being major limiting factor. There were three rate treatments of silicate fertilizer application; the amount of silicate fertilizers needed to adjust the available soil silicate contents to 130, 200, and $270mg\;kg^{-1}$ was applied, in the first year only. There was an additional plot; applying the amount of silicate fertilizer needed to adjust soil available silicate to 130 ppm every year, which would serve as the base for the evaluation of residual effects of silicate fertilizers in the plots where different rates of silicate fertilizer were applied. From the yield data in first year, it was found that optimum available silica in the soil are $154mg\;kg^{-1$ and $160mg\;kg^{-1}$, in Jisan and Seogcheon soils, respectably. The duration of residual effects of silicate fertilizer was different depending upon the amount of applied silicate fertilizers and the soils. The higher the application rate, the residual effect lasted longer, and the residual effect was lasted longer in Jisan(clay loam) soil than in Seogcheon(sandy loam) soil. During four years, sum of the rate of contribution to increase available soil silica of applied silicate fertilizer in different soils ranged 18.6% and 24.1% in Jisan soil and Seogcheon soil, respectively. This may suggest that much portion of applied silicate would be either lost from the soil or remain in the soil as insoluble form. This deserves further study.