• The Korean Journal of Food And Nutrition
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• v.27 no.5
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• pp.851-858
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• 2014

Goami2, Goami3 and Goami4 were identified as fiber-rich rice cultivars which were developed by mutation breeding with Ilpum. The purpose of this study was to develop a method for producing Makgeolli with the fiber-rich rice cultivars, Goami2, Goami3, Goami4, and to investigate the characteristics of Makgeolli during the fermentation process. Makgeolli was produced herein by fermentation steamed rice (SR), raw rice flour (RF), and steamed rice flour (SF) from Goami2, Goami3, Goami4, Ilpum and Sealgaeng rice cultivars. The physicochemical characteristics including alcohol and sugar content, pH, total acidity, TDF (total dietary fiber), and color of the Makgeolli samples were analyzed. Makgeolli produced with Ilpum and Sealgaeng showed satisfactory fermention characteristics in alcohol and sugar content when SR, RF and SF were used. In the case of Goami2, Goami3, and Goami4, the use of SF resulted in 17.2~20.1% alcohol content, whereas only 10% alcohol was produced by SR. The sugar contents in the SF-makgeolli samples were also higher ($9{\sim}10^{\circ}Brix$) than in the SR-makgeolli ($5.35{\sim}5.44^{\circ}Brix$) for Goami2 and Goami4 cultivars. The dietary fiber contents of the Makgeolli samples produced using SF from the fiber-rich rice cultivars were higher (1.35~1.52 g/100 mL) than those produced with Ilpum and Sealgaeng (0.74~0.87 g/100 mL). From these results, it may be suggested that SF would be an appropriate material to brew Makgeolli using fiber-rich rice cultivars to obtain better physicochemical and functional qualities.

• Journal of Photoscience
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• v.9 no.2
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• pp.162-165
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• 2002

Rice is widely cultivated in various regions throughout Asia. Over a five-year period, we investigated the effects of supplemental UVB radiation on the growth and yield of Japanese rice cultivars in the field. The findings of that study indicated that supplemental UVB radiation has inhibitory effects on the growth and grain development. Furthermore, we investigated the sensitivity to UVB radiation of rice cultivars of 5 Asian rice ecotypes, and found that rice cultivars vary widely in UVB sensitivity. The aim of our study is improving UVB resistance in plants by bioengineering or breeding programs. In order to make it, there is need to find the molecular origin of the sensitivity to UVB. Cyclobutane pyrimidine dimer (CPD) is major UV-induced DNA lesions. Plants possess two mechanisms to cope with such DNA damage. The first is the accumulation of UV-absorbing compounds. Our previous data showed that the steady-state CPD levels in leaves of rice grown under chronic radiation in any culture were not so greatly influenced by the increased UV-absorbing compounds content, although there was a significant positive correlation between the CPD levels induced by challenge UVB exposure and the UV-absorbing compounds content. The other is the repair of DNA damage. Photorepair is the major pathway in plants for repairing CPD. We found that the sensitivity to UVB could seriously correlate with the low ability in CPD photorepair in rice plants. These results suggest that photo lyase might be an excellent candidate for restoration by way of selective breeding or engineering in rice.

• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.394-400
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• 2008

Blast resistance of one hundred and thirty-one rice cultivars bred in Korea was tested with thirty Korean isolates and twenty-two Philippines isolates using three screening methods. In the blast nursery conducted in Korea and in the Philippines, average disease index of rice cultivars were 4.6 and 2.2, respectively. Seventy-nine cultivars showed different resistance reaction in Korea and in the Philippines, and 19 cultivars showed the same resistant reaction in two locations. In the seedling test, Korean blast isolates displayed different levels of virulence. 93-093, a Korean isolate, was compatible with 90 cultivars whereas 97-057 showed a compatible reaction with 13 cultivars. Twenty-three cultivars showed high level of resistance against Korean and Philippines isolates but Chucheongbyeo, Heugnambyeo, and Manmibyeo showed susceptible reaction to all blast isolates. Through the sequential planting test in Korea and in the Philippines, Palgongbyeo and Seomjinbyeo displayed durable resistance, and Nagdongbyeo and Gihobyeo showed high level of disease infection over the planting time. These results indicate that blast isolates collected in two countries have different genetic background and number of compatible isolates should be considered in definition the durability of rice cultivar to rice blast.

• The Korean Journal of Food And Nutrition
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• v.25 no.4
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• pp.762-769
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• 2012

In order to study the cooking characteristics of four rice cultivars of Seolhyangchal, Baegjinju, Ilpum and Haiami, we investigated the relationship between the textures of cooked rice and their physicochemical properties. Different levels in grain weight. length/width ratio and amylose content were observed among the four rice cultivars. There was no significant difference in the amylopectin chain length distribution among the cultivars. Water absorptions of rice grains during soaking were completed between 30 and 40 min, with Haiami showing the slowest absorption. Significant differences in the viscosity properties of rice flour were found by a Rapid Visco Analyser. Baegjinju with low amylose content had the highest viscosity in paste breakdown. According to the DSC results of rice starches, there were significant differences in the onset, peak and conclusion temperatures of the endothermic peak. Gelatinization enthalpy showed energy content changes between 4.20 and 6.97 J/g, with the lowest change in Haiami. Texture properties of cooked rice were assessed using a Texture Analyzer, which showed that the hardness of cooked rice was decreased with soaking than without soaking. However, this finding was not applicable for Haiami rice.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.4
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• pp.311-316
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• 2017

The relationship between mean air temperature after heading and starch characteristics of colored rice grains was investigated using three colored rice cultivars. Pasting temperature within each rice cultivar with different harvest times differed. The pasting temperatures of two rice cultivars, Hongjinju and Joseongheugchal, reached the highest at 40 days after heading and decreased during the late harvest time. Distribution of amylopectin in the Hongjinju rice cultivar at the earlier harvest time contained a greater number of very short chains with the degree of polymerization (DP) between 6 and 12 and fewer chains with a DP from 13 to 24 than that of the later harvest time. However, there was little difference in the distribution of the longer chains of $25{\leq}DP{\geq}36$ and $37{\leq}DP$ for latter harvest times compared to that of the earlier ones. It was suggested that the structure of amylopectin affected the varietal differences in patterns of chain length of amylopectin during grain filling. In addition, the control of ripening was different from that causing the pigment effects in the fine structure of amylopectin in the three colored rice cultivars. Larger starch granules were observed in the Joseongheugchal rice cultivar and smaller granules occurred in the Hongjinju rice cultivar. The present study revealed that later harvest times led to a clear increase in the mean granule size of starch in the three colored rice cultivars.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.43-43
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• 2017

During grain filling period, rice is affected by many environmental factors; including temperature, water, radiation and soil nutrition condition. In future climate, greater shading and heat tolerance will be required in rice. In this study, the effect of shading and high temperature on spikelet sterility was conducted on fourteen Vietnamese cultivars. Field experiments were studied in 2015 and 2016 to evaluate the response of Vietnamese cultivars under high temperature during grain filling stage. The high temperature and shading were applied by closing two sides of growth chamber and covered by a black cloth (50% reduced solar radiation) under the field condition after the first cultivar heading. The sterility increased significantly under high temperature and shading. The highest percentage sterile spiketlets was observed in 'Jasmine 85' (71.7%) under shading and in 'OM4900' (53.4%) under high temperature in 2015 and 2016, respectively. Among the treatments, the percentage of sterile spekelets in Vietnamese cultivars under shading was highest which was 54.9% and 41.8% in 2015 and 2016, respectively. Yield components reduced significantly in both of shading and high temperature. Corresponding with significantly decrease in yield components, the yield in high temperature and shading decreased strongly in both 2015 and 2016.

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.215-222
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• 2008

Fifty-two Korean japonica rice cultivars were analyzed for leaf blast resistance and genotyped with 4 STS and 26 SSR markers flanking the specific chromosome sites linked with blast resistance genes. In our analysis of resistance genes in 52 japonica cultivars using STS markers tightly linked to Pib, Pita, Pi5(t) and Pi9(t), the blast nursery reaction of the cultivars possessing the each four major genes were not identical to that of the differential lines. Eight of the 26 SSR markers were associated with resistant phenotypes against the isolates of blast nursery as well as the specific Korean blast isolates, 90-008 (KI-1113), 03-177 (KJ-105). These markers were linked to Pit, Pish, Pib, Pi5(t), Piz, Pia, Pik, Pi18, Pita and Pi25(t) resistance gene loci. Three of the eight SSR markers, MRG5836, RM224 and RM7102 only showed significantly associated with the phenotypes of blast nursery test for two consecutive years. These three SSR markers also could distinguish between resistant and susceptible japonica cultivars. These results demonstrate the usefulness of marker-assisted selection and genotypic monitoring for blast resistance of rice in blast breeding programs.

• Korean Journal Plant Pathology
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• v.13 no.2
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• pp.85-89
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• 1997

Etiological components of the rice cultivars possessing durable resistance to rice blast were evaluated. In the greenhouse test by artificial inoculation, number of leaf blast lesion in Dongjinbyeo was not increased by any race of the pathogen, while the lesion number on the resistant cultivar Palgongbyeo and susceptible cultivar Jinmibyeo was increased rapidly. Size of the lesion in Dongjinbyeo was smaller and progressed more slowly than the resistant cultivar Palgongbyeo until 11 days after inoculation. Latent period in Dongjinbyeo was intermediate. However, the period was significantly variable depending upon the races. Least amount of conidia was produced in Dongjinbyeo by race KJ-107 and the number of conidia was decreased rapidly from 11 days after inoculation.

• Preventive Nutrition and Food Science
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• v.12 no.2
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• pp.103-110
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• 2007

The protein profiles among Korean rice cultivars were assessed by total protein determination, solubility fractionation, SDS-PAGE analysis and scanning densitometry. In the extraction of protein, the SDS/urea system at a neutral pH was more efficient than that at alkaline pH. The determination of total protein showed that the protein content was similar among cultivars, ranging from 87.9 to 92.7 mg/g dry weight. Additionally, the water/NaCl-soluble protein fraction, containing 14${\sim}$16 kDa albumin and 22 kDa globulin ${\alpha}$-globulin, was also similar among cultivars, with a range of 9.94 to 11.98 mg/g dry weight. The SDS-PAGE/densitometry of total protein showed that there was no discernable difference in proteins of higher molecular weights among various cultivars, whereas the amount of lower molecular weight proteins (14${\sim}$16 kDa) is somewhat variable among cultivars. Furthermore, SDS-PAGE analysis of water/NaCl-soluble and propanol-soluble fractions indicates that there is a discernible change in the content of albumin, globulin or prolamin among cultivars. Thus, the PAGE/densitometry method, preceded by solubility fractionation, is useful for examining differences in protein profiles of rice cultivars.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.789-795
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• 2007

This study was undertaken to investigate the producibility of processed foods utilizing 6 newly developed non-glutinous rice cultivars. First, cooked rice, cake, cookies, bread, and slender rice cake sticks were prepared with the newly developed cultivars; then their physicochemical and textural properties were evaluated. The rice samples had similar pasting temperatures and peak times, but different viscosities and other pasting properties. The textural analysis results suggested that 'Chucheong' was appropriate for cooked rice due to its low amylose content; hardness, and springiness; 'Ilphumbyeo' for rice cakes due to its high amylose content, moderate cohesiveness and adhesiveness, and low hardness; 'Ilphumbyeo' for cookies due to its high amount of protein, and low cohesiveness and adhesiveness; 'Ilphumbyeo' for bread due to its high amylose content, moderate hardness, and low consistency; and 'Ilphumbyeo' for the slender rice cake sticks due to its low hardness, moderate breakdown, paste viscosity, and setback.