• Korean Journal of Agricultural Science
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• v.37 no.1
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• pp.61-68
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• 2010

Rice bran proteins from different cultivars(Youngan, Sindongjin, Suwon 511) were extracted with Xylanase using orthogonal analysis method and their functional properties were investigated. The optimum extraction conditions, based on protein content in the extract found to be at 1 wt% xylanase, pH 7 and 50:1, solvent to rice bran ratio(v/w %). Nitrogen solubility indices(NSI) of rice bran protein concentrates were shown a minimum value at pH 4 ranged 2~23%, varied with different cultivars and a maximum (NSI${\geq}$90% for all cultivars) at pH 10. As for water adsorption and fat adsorption capacity, rice bran protein concentrates were shown to be better than Na-caseinate and isolated soy protein, respectively. Emulsifying activities were observed high in order of Na-caseinate>Youngan rice bran protein>Shindongjin rice bran protein>Suwon 511 rice bran protein>isolated soy protein. In general, the surface tension of rice bran protein solution($10^{-3}$ wt%, 5 mM bis-tris, pH 7) was increased with increasing concentrations and found a minimum value near pI. On heating, it was decreased slightly with increasing temperatures up to $70^{\circ}C$ and then increased above $80^{\circ}C$. Addition of sodium chloride was made the surface tension decrease. In conclusion, with Xylanase, rice bran protein concentrate can be successfully extracted from the rice bran of different cultivars and the Youngan rice bran protein was thought to have best functionality among rice cultivars tested. It might be used as a milk protein substitute.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.292-296
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• 2006

Three rice cultivars of Goami2 (G2), Ilpumbyeo (IP), and Baegjinju (BJJ) of which physicochemical properties are significantly different, were blended by a simplex-lattice mixture design. The effect of blending those rice cultivars on pasting and texture properties were observed. Rapid Visco Analysis (RVA) indicated that the onset gelatinization temperature of pure blend of G2 rice $(83.80{\pm}0.07^{\circ}C)$ was higher than that of IP $(68.08{\pm}0.01^{\circ}C)$ and BJJ $(68.08{\pm}0.04^{\circ}C)$. Increasing G2 rice resulted in lower peak and breakdown viscosity, and adhesiveness and cohesiveness, whereas higher setback viscosity and hardness. Pasting and texture properties of IP and BJJ indicated that G2 rice has quite different physical characteristics compared to IP and BJJ. Thus, it is expected that blending those three rice cultivars can be used to formulate a desirable rice blend on purpose, furthermore to promote the consumption of G2 rice, which has higher indigestible carbohydrate contents.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.4
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• pp.257-260
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• 2000

The content of anthocyanin, cyanidin 3-glucoside (C3G) and the peonidin 3-glucoside (P3G) from 591 rice cultivars and the antioxidative activities of MeOH extract from 8 rice cultivars were evaluated. Among them, C3G content of pigmented rice were ranged from 0 to 451.9mg in 100 g brown rice, while the P3G contents were in the range from 0 to 42.7mg in 100g brown rice. There was no correlation between C3G and P3G content. Total anthocyanin content ranged from 0 to 475.1mg in 100g brown rice. The antioxidative activity, the scavenging activity on DPPH (2,2-diphenyl-picryl-hydrazyl) radical of MeOH extracts from rice grain, were different according to cultivars. The activity of blockish purple pericarp rice cultivars was twice stronger than that of white pericarp cultivar. Especially, the antioxidative activity of Heugjinjubyeo was four times stronger than that of white pericarp cultivar. The scavenging effect on DPPH radical in rice extracts was related to the total anthocyanin contents of the extracts.

• Korean Journal of Plant Resources
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• v.11 no.1
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• pp.93-100
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• 1998

This study was to investigate the dry weight, the amount of Na+ and K+ water potential and leaf photosynthesis rate in plants for determining the salt tolerance mechanism in rice cultivars on soil and solution culture with NaCl. The results obtained in this study are summarized as follows ; In general, rice cultivars, cv. Tetep and Jinbu, having high salt tolerance in ID(identified on dry matter production level) showed the higher salt tolerance in RGR (relative growth rate), compared with rice cultivars(cv. Nonglim 41ho, Dunraebyeo and Sobackbyeo) having low salt tolerance. The contents of Na in rice differed depending on culivars and plant parts. Tetep contained 2.9times higher amounts of Na+ than leaf blade and root part. High salt tolerance cultivar Obongbyeo showed a larger decrease in osmotic potential than low salt tolerance cultivar Dunraebyeo suggesting that osmotic adjustment was developed under salt stress conditions in a salt tolerant cultivar . In order to know the IY(identified on grain yeild level using rice cultivars having different salt tolerance the capacity of photosyntheiss was investigated. The capapcity of photosynthesis in cv. Tetep and Obongbyeo having high salt tolerance was much higher that in cv.Dunraebyeo and Nonglim 41 having low salt tolerance.

• Journal of Crop Science and Biotechnology
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• v.11 no.1
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• pp.17-22
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• 2008

Aromatic rice has become popular owing to its aroma. Growing demand for aromatic rice has spurred interest in the development of domestic cultivars that offer similar combinations of grain attributes such as texture, cooking characteristics, aroma, and taste. In this study, the most important agronomic attributes and aroma of 26 cultivars from Afghanistan, Iran, and Uzbekistan, and controls from Japan, Thailand, and India were characterized. Also $F_2$ populations derived from the cross between(Jasmine 85 aromatic$\times$Nipponbare non-aromatic) and(Jasmine 85$\times$Basmati 370 aromatic) were obtained. Tasting individual grains, cooking test, 1.7% KOH sensory test, and molecular marker analysis have been applied to distinguish between aromatic and non-aromatic rice. Diversity for some traits of agronomic importance, such as plant height was detected among countries, e.g. Afghan cultivars classified as tall, and Iranian and Uzbek intermediate and short, respectively. Differentiations of panicle, grain, leaf, basal internode, and culm dimension among rice cultivars, indicating the source of rice diversity in Central Asia. According to the results, 6 of 10, 2 of 7, and 0 of 6 of Afghan, Iranian, and Uzbek rice cultivars were scored as aromatic, respectively. Therefore, Afghan cultivars are a good source of aromatic rice germplasm for Central Asia. The expression between aromatic and non-aromatic, and aromatic and aromatic combinations has been evaluated. The observed segregation ratio of these crosses in the $F_2$ populations was tested by $x^2$ analysis against the expected ratio for a single gene. A segregation ratio of 3:1 between non-aromatic and aromatic combination has been detected, while segregation has not been detected between the aromatic and aromatic combinations. Also, parallel results were obtained from the tested aromatic rice cultivars. Thus, our results suggest that a single recessive gene controls aroma in all aromatic rice cultivars.

• Proceedings of the Botanical Society of Korea Conference
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• 1994.09a
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• pp.29-39
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• 1994

Serious issues about the changes in the environmental conditions on earth associated with human activities have arisen, and the interest in these problems has increased. It is urgent to determine how the expansion of terrestrial UV-B radiation due to the stratospheric ozone depletion influences living matters. In this connection, we have been investigating the effects of UV-B radiation on the growth of rice cultivars (Oryza sativa L.). We report here some physiological and genetic aspects of resistance to inhibitory effects of UV-B radiation on growth of rice cultivars as described below. Elevated UV radiation containing large amount of UV-B and a small amount of UV-C inhibited the development of plant height, the photosynthetic rate and the chlorophyll content in rice plants in a phytotron. Similar results were obtained in experiments, in which elevated UV-V radiation. Similar results were obtained in experiments, in which elevated UV-B radiation (transmission down to 290 nm) was applied instead of UV-B radiation containing a small amount of UV-C. The inhibitory effects of UV radiation was alleviated by the elevated CO2 atmospheric environment or by the exposure to the high irradiance visible radiation. The latter suggested the possibility that the resistance to the effects of UV radiation was either due to a lower sensitivity to UV radiation or to a greater ability to recover from the injury caused by UV radiation through the exposure to visible radiation. The examination of cultivar differences in the resistance to UV radiation-caused injuries among 198 rice cultivars belonging to 5 Asian rice ecotypes (aus, aman, boro, bulu and tjeleh) from the Bengal region and Indonesia and to Japanese lowland and upland rice groups showed the following: Various cultivars having different sensitivities to the effects of UV radiation were involved in the same ecotype and the same group, and that the Japanese lowland rice group and the boro ecotype were more resistant. Among Japanese lowland rice cultivars, Sasanishiki (one of the leading varieties in Japan) exhibited more resistance to UV rakiation, while Norin 1 showed less resistance, although these two cultivars are closely related. It was thus indicated that the resistance to the inhibitory effects of UV radiation of rice cultivars is not simply due to the difference in the geographical situation where rice cultuvars are cultivated. Form the genetic analysis of resistance to the inhibitory effects of UV radiation on growth of rice using F2 plants generated by reciprocally crossing Sasanishiki and Norin 1 and F3 lines generated by self-fertilizing F2 plants, it was evident that the resistance to the inhibitory of elebated UV radiation in these rice plants was controlled by recessive polygenes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.84-91
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• 2006

This study was carried out to comparatively evaluate growth characteristics of rice cultivars under rice-mono (conventional) and rice-Chinese milk vetch (Vetch) cropping system. Six rice cultivars such as Geumobyeo, Pungmibyeo, Hwayeongbyeo, Sobibyeo, Junambyeo and Dongjinbyeo were tested in 2005. The results obtained are summarized as follows ; plant height and culm length of all the tested cultivars at heading and harvest time were shorter in rice-vetch cropping system than conventional, however, nitrogen content of rice plants at heading and harvesting time was higher in rice-vetch cropping system. The total amount of nitrogen of rice plants was higher in conventional than rice-vetch cropping system. Nitrogen content of rice plant and uptake of Pungmibyeo was the highest of all the tested cultivars in both cropping systems. Generally, grain yietd ef tested cultivars seemed to be higher in conventional than rice-vetch cropping system. And it was the highest in Junambyeo as compared to those of other cultivars. Head rice ratio and protein content were higher in rice-vetch cropping system.

• Korean Journal of Organic Agriculture
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• v.18 no.1
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• pp.75-82
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• 2010

The purpose of this study is to investigate an occurrence rate of rice stripe virus disease under different rice transplanting time and different rice cultivars. After final harvest, the yield of rice infected by rice stripe virus was obtained on Wangchal cultivar compared to uninfected rice. The results obtained as following: 1) Yield of rice infected by rice stripe virus was decreased by 64% with reduction of culm length, pancile length, number of spike, number of spikelet, and grain filling compared to uninfected rice, 2) An occurrence rate of rice stripe virus disease under different rice planting season was high as order of May 30 > June 15 > July 1. In additional, to reduce a rice stripe virus disease on higher disease occurrence region and susceptible cultivars, rice planting season will be accepted on and after June 15, and 3) Eighteen cultivars were resistance cultivars such as Hwayeongbyeo, Onnuri, Ilmibyeo, Nampyongbyeo, Dongjin2ho, Hopumbyeo, Hwangkeumnuri, Malgeumi, Saenuri, Pungmi1ho, Haechanmulgyeo, Hwangkeumnodeul, Chilbobyeo, Dongjinbyeo, Younganbyeo, Junambyeo, Samkwangbyeo, and Nakdongbyeo. Twenty-one cultivars were susceptible cultivars such as Odaebyeo, Unkwangbyeo, Shinungbong1ho, Manabyeo, Hopyongbyeo, Borami, Damibyeo, Hwangchalbyeo, Sulgengbyeo, Nongrim6ho, Sasanishigi, Yunishigari, Chungmubyeo, Dongjin1ho, Huknambyeo, Guromy, Shanghehanghulna, Heukchalbyeo, Heukhwangbyeo, and Aranghwangchalbyeo.

• Journal of the East Asian Society of Dietary Life
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• v.8 no.4
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• pp.469-480
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• 1998

This study was carried out in order to investigate the processing adaptability of Jeung-pyun. We used rice materals that were developed domestically for improving the utilization of rice. Six cultivars (Ilpoombyeo, Hwasungbyeo, Dasanbyeo, Daeribbyeo 1, Hyangmibyeo 1, Hyangmibyeo 2) of rice were used for making Jeung-pyun. In physicochemical properties of rice, Hwasungbyeo had the highest amylose content (20.4%) and Hyangmibyeo 2 had the lowest one(14.9%). Lipid content was 0.23%(Daeribbyeo 1)-0.43%(Ilpoombyeo), protein content was 7.94%(Ilpoombyeo) -8.43%(Dasanbyeo), and ash content was 0.15%(Hyangmibyeo 2)-1.24% (Daeribbyeo 1). In volume and specific volume of the 3 hour fermented Jeung-pyuns, Ilpoombyeo, Hwasungbyeo, Hyangmibyeo 2 were higher, but in the 7 hour fermented Jeung-pyuns, Dasanbyeo, Daeribbyeo 1, Hyangmibyeo 1 were higher, In the sensory evaluation of the test Jeung-pyuns, the overall quality of the 3 hour fermented Jeung-pyuns was not significantly different among the rice cultivars, whereas in the 7 hour fermented Jeung-pyuns Hyangmibyeo 2 had the lowest values. When the 7 hour fermented Jeung-pyuns were stored at 2$0^{\circ}C$, the hardness and brittleness of Jeung-pyuns were respectively increased, the cohesiveness was respectively decreased. The elasticity was not significantly different among the rice cultivars with storage days, and the gumminess was significantly difference between rice cultivars, respectively increasing during storage, but Hyangmibyeo 2 was the lowest, not increased. In insturmental characteristics of Jeung-pyuns, the hardness was correlated with amylose content and the brittleness and gumminess were highly correlated with the hardness.

• Research in Plant Disease
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• v.7 no.2
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• pp.102-106
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• 2001

Currently the rice false smut caused by Ustilaginoidea virens (Cooke) Takah. has occurred widely in Korea. A survey on the disease incidence at rice fields in 8 inland provinces was carried out in 2000, showing that the disease occurred at 104 (7.5%) out of 1,152 rice fields examined, ranging from 1.5% to 13.7% in provincial average. It was found that the disease incidence was greatly affected by local weather conditions and rice cultivars. In case of the most susceptible cultivar Namchunbyeo, the disease incidence was only about 1.3% in Icheon, while it was over 20% in Namwon which had weather conditions of the shorter sunshine period (about 64%) and the higher amount of precipitation (about 130%) during the rice cultivation than Icheon. In Icheon, artificial inoculation of the pathogen failed to induce the disease, probably because of the weather conditions unfavorable to the disease development, which also suggests that its incidence may be dependent on the weather conditions. Susceptibility of rice cultivars to the disease varied greatly; eight resistant cultivars including Heukjinjubyeo were not damaged by the disease, but 2 cultivars including Geumnambyeo and Namchunbyeo were severely damaged, having more than 20% of the disease incidence. Among chemicals tested fur the control of the rice false smut tebuconazole WP showed the highest control efficacy of 83∼88% on cvs. Geumnambyeo and Namchunbyeo. Other chemicals such as azoxystrobin WP and ferimzone WP also effectively suppressed the disease development in the field trials.