• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.696-701
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• 2003

Rice seeds of 4 cultivars including Whachung and Nampung, of the non-waxy rice cultivars, and Shinsunchalbyeo and Whachungchabyeo, of the waxy rice cultivars, were germinated at $27^{\circ}C$ for 3 days to compare the changes in some physico-chemical properties of the starch granules and the starch-hydrolysing enzyme activities during germination, respectively. With the starch granules, the amount of long glucose chains from amylose molecules were reduced in the non-waxy rices, while the chain length increased in the waxy rices. In the distribution profile of the glucose chain length from amylose molecules, we could observed that the chain length with DP (degree of polymerization) ranged 33 to 66 increased with the decreasing rate of the chain length with that above 130, regardless of the waxiness of rices. In addition, we observed that in contrast to a increase in chain length with DP ranged 14 to 33, the amount of short chains from A chain fraction decreased. Germination induced slight reduction in the polymerization rate of starch granules, and decrease in both initiation and termination temperatures for the gelatinization. ${\alpha}-Amylase$ activity of rices germinated for 3 days found to he higher than that of malt. Especially, the activity of Shinsunchalbyeo was revealed to be highest, about two fold higher than that of malt. In contrast, ${\beta}-amylase$ of the waxy rice found to be considerably less active than malt, although the waxy showed prevalent activity as compared to the non-waxy rices.

• Korean Journal of Agricultural Science
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• v.18 no.2
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• pp.93-98
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• 1991

This research was undertaken to clarify derivation of resistance of Japonica type of rice varieties to rice strip virus. 1. The source of resistance to the rice strip virus in rice cultivars of Nagdongbyeo, Hwaseongbyeo, Gwangmyeongbyeo, Yeongdeogbyeo, Dongjinbyeo, Gyehwabyeo, Hwacheongbyeo, Suweon 362, Iri 390, Milyang 64, Milyang 96 and Milyang 101 was derived from rice cultivar of Modan. 2. The resistance of rice cultivars Donghaebyeo, Sinseonchalbyeo, Palgongbyeo, Hwajinbyeo and Somjinbyeo to the rice strip virus was derived from cultivar Milyang 23 and/or Nangdongbyeo. 3. The resistance of cultivars Jinjubyeo, Tamjinbyeo and Yongsanbyeo to the rice strip virus was derived from cultivar HR 769 and/or Milyang 20. 4. The resistance of cultivar Daecheongbyeo to the rice strip virus was deriverl from cultivar Nagdongbyeo and/or HR 769.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.3
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• pp.197-203
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• 1991

Several types of endosperm and embryo mutants were induced by the treatment of MNU (N -methly- N -nitrosourea) on fertilized egg cell of rice plant. These mutants were named as dull. waxy, white core, floury, sugary, shrunken, colored seed coat and giant embryo according to their appearence, micro-scopic feature on SEM and amylose content. White cored mutant was the most frequent one among them. All of the mutants were segregated as controlled by a single recessive gene except 47320 (dull). Futher studies on the genetics and physico-chemical properities of the mutants are ongoing.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.75-81
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• 2000

The processing properties for rice bread were examined using eight kinds of endosperm mutant rice. The varietal differences among eight kinds of endosperm mutant rice having the respective sugar contents and amylose contents were studied. The water absorptions of these eight cultivars were observed to have significant differences among the cultivars, revealing the water absorption ability of Shrunken(shr.) was 61.5%, and that of Punchilmi(fl) was 48.4%. In addition, the experiments using Whachungbyeo, Nampungbyeo and their mutant cultivars showed that the maximum water absorption was tend to be negatively correlated with the amylose content of each rice cultivars. This study also showed that the rice breads made by dry-milling was better in shape, mechanical properties(hardness, springiness, adhesiveness, chewiness) and texture tested using sensory evaluation than that made by wet-milling.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.4
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• pp.494-503
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• 1995

The selection of salt tolerant rice variety needs an effective method in its testing. Salinity of irrigated water, 0.5% at seedling stage, 0.6% at tillering stage, and 0.9% at panicle formation stage were treated to test salt tolerance of rice using 45 cultivars. At tillering stage, salty water irrigation reduced plant height to 22.6% in early maturing rices(EMR), 30.5% in medium maturing rices(MMR), and 20.9% in medium-late maturing rices(MLMR), and also reduced number of tillers to 11.2% in EMR, 36.2% in MMR, and 36.0% in MLMR compared to rices grown in non-salty water irrigation. At panicle formation stage of rice, salty water irrigation affected plant height and tiller numbers that showed varietal differences. As salt tolerant rice cultivars, Daegwangbyeo, Namweonbyeo, Sinseonchalbyeo, Gyehwabyeo, and Daeyabyeo were selected. Jinbubyeo, Donghaebyeo, and Tamjinbyeo were weak in salty water irrigation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.5
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• pp.413-417
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• 1993

This study was conducted to breed various cytoplasmic genetic male sterile (CGMS) and restorer lines with backgrounds of Korean japonica rice varieties. The CGMS line BT-CMS was crossed with the restorer line AR-3. The fertile $F_1 was emasculated and crossed with the Korean japonica rice varieties of the early maturing Sobaegbyeo, Odaebyeo, Gwanagbyeo and Daeseongbyeo, and of the medium maturing Hwajinbyeo, Paldal, Suwon 224 and Iri 386, and of the late maturing Nagdongbyeo, Palkweng, Hwacheongbyeo and Milyang 97. Each of the three way cross $F_{1S} was segregated into fertile and sterile individuals. The sterile individuals in each cross were discarded and the fertile individuals were emasculated and backcrossed with the Korean japonica rice varieties. The same process was applied from BC$_1$F$_1$ to BC$_4$F$_1$ generation. In the ${BC_4}{F_1}of each cross, the male sterile individual was crossed with the recurrent Korean japonica variety which was maintainer of male sterility. The male sterile lines of ${BC_6}{F_1}were named as Sobaegbyeo R, Odaebyeo R, Gwanagbyeo R, etc. The fertile individuals homozygous in pollen fertility were selected from the ${BC_4}{F_2}generation and named as Sobaegbyeo R, Odaebyeo R, Gwanagbyeo R, etc. Agronomic characteristics of the CGMS, restorer lines with backgrounds of Korean japonica, and the recurrent Korean japonica rice varieties grown in the field condition were compared. Culm length of the CGMS lines tended to be shorter than that of the recurrent parent, however no significant differences in heading date, panicle length and yield component were found among the CGMS, restorer and recurrent lines.

• Korean Journal of Food Science and Technology
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• v.33 no.5
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• pp.540-544
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• 2001

The quality characteristics for brown rice flake were examined using eight kinds of brown rice cultivars such as Shinsunchalbyeo, Shinsunchal giant embryonic rice, Whachungchalbyeo, Whachungchal giant embryonic rice, Whachungbyeo, Whachung giant embryonic rice, Nampungbyeo, and Nampung giant embryonic rice. The qualities of grain such as the released reducing sugar, water absorption rate and hardness of grain are examined with different temperature and time at sedimentation in water and pressed grain-brown rice flake are prepared after sedimentation in $60^{\circ}C$ water for 5 hours. The brown rice flakes prepared from the giant embryonic type rice cultivars showed higher expansion volume, lower hardness, more crispness, longer bowl life time and better taste than that prepare from normal type rice cultivars, which showed the giant embryonic type rice cultivars were appropriate for brown rice flakes. Among the giant embryonic type rice cultivars, the glutinous rice varieties were better to prepared the brown rice flakes than its normal rice cultivars. The water absorption index of flakes tested were positively correlated with expansion volume and bowl life hardness. From tested sensory evaluation were shown to be negatively correlated with water absorption index. Among the tested cultivars, Shinsunchal giant embryonic and Wachungchal giant embryonic rice were most appropriate for brown rice flakes preparation.

• Applied Biological Chemistry
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• v.46 no.3
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• pp.189-194
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• 2003

Rice seeds of 4 cultivars including Whachung-giant embryonic rice and Nampung-giant embryonic rice, as a group of the non-waxy rice cultivars, and Shinsunchal-giant embryonic rice and Whachungchal-giant embryonic rice, as that of the waxy rice cultivars, were germinated at $27^{\circ}C$ for 3 days to compare the changes in some physicochemical properties of the starch granules and the starch-hydrolysing enzyme activities during germination, respectively. ${\alpha}-Amylase$ activity of rices germinated for 3 days found to be higher than that of malt. Especially, Whachung-giant embryonic rice and Shinsunchal-giant embryonic rice were greater in activity than other rice cultivars and possessed the activities double that of malt. In contrast, ${\beta}-amylase$ of germinated rice found to be considerably less active than malt, although the giant embryonic rice group showed prevalent activity as compared o the normal rice group. With the starch granules, the amount of long glucose chains from amylose molecules were reduced in the non-waxy type giant embryonic rices, while the chain length increase was found in the waxy type giant embryonic rices. For the distribution profile of the glucose chain length from amylopectin molecules, we could observed that the chain length with DP (degree of polymerization) ranged 33 to 66 and 14 to 32 increased with the decreasing rate of that above 67 and below 13 regardless of starch waxiness. With non-waxy type of giant embryonic rices, susceptibility for glucoamylase were found to reduce along with germination, however, increase in susceptibility was observed with waxy rice types. In addition, we found the reduction in both initiation and termination temperature, and enthalpy for gelatinization.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.5
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• pp.600-607
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• 1996

Colored rices have been used for specific purposes by rice consumers due to the color and nutritive values empirically recognized. In this study, varietal variations of pigmentation and nutritive values were investigated in brown, red, purple and black rices. Pigments were localized in seed coat to pericarp region in all varieties tested. Pigments were slightly residued on the surface of milled rice. Anthocyanin content per g brown rice was 1.63~17.62 $\mu\textrm{g}$ in brown and reddish-brown rices, 3.56~11.10 $\mu\textrm{g}$ in red rices, 28.11~401.22 $\mu\textrm{g}$ in purple rices, and 3, 665.98 $\mu\textrm{g}$ in a black rice. A vatiety DZ 78 showed the highest protein content out of colored rices analyzed for protein. Normal and colored rices were found to have the similiar composition of amino acids, and so was in between brown rice without embryo and milled rice. Colored rices, L $K_1$B-4-12-1-1 and DK 1, showed higher content of vitamin $B_1$ compared with Hwacheongbyeo, a check variety of no specific color, and L $K_1$B-2-1-1 and L $K_1$B-4-12-1-1 showed much higher content of vitamin B2 in brown rice without embryo. Cation contents such as $K^{+}$, $Mg^{2+}$, $Ca^{2+}$ and F $e^{2+}$ were significantly increased in most of the colored rices tested implying that the increase might be associated with color pigmentation.ation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.5
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• pp.418-424
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• 1993

In order to test combining ability of the cytoplasmic-genetic male sterile(CGMS) and restorer lines with backgrounds of Korean japonica rice varieties, diallel crosses were made among the early maturing CGMS lines Sobaegbyeo A, Odaebyeo A, Gwanagbyeo A and Daeseongbyeo A, and the restorer lines Sobaegbyeo R, Odaebyeo R, Gwanagbyeo Rand Daeseongbyeo R, and among the medium maturing CGMS lines Hwajinbyeo A, Paldal A, Suwon 224 A and Iri 386 A and the restorer lines Hwajinbyeo R, Paldal R, Suwon 224 Rand Iri 386 R, and among the late maturing CGMS lines Nagdongbyeo A, Palkweng A, Hwacheongbyeo A and Milyang 97 A and the restorer lines Nagdongbyeo R, Palkweng R, H wacheongbyeo Rand Milyang 97 R. The fourty eight combinations of the hybrids, their parents and the maintainers were grown in field condition in 1992. General combining ability, relative specific combining ability and relative combining ability for yield of the CGMS and restorer lines were tested. Combining ability of the CGMS lines Odaebyeo A, Iri 386 A, Nagdongbyeo A and Palkweng A, and of the restorer lines Odaebyeo R, Hwajinbyeo R, Hwacheongbyeo Rand Palkweng R was relatively high. Heterobeltiosis for grain yield over the better parent of the early maturing hybrids ranged from -17 % to 15%, and that of the medium maturing ones from -4% to 22%, and that of the late maturing ones from -46% to 30% respectively, Standard heterosis over the standard variety of the early maturing hybrids ranged from -13 % to 12 %, and that of the medium maturing ones from 0 % to 26%, and that of the late maturing ones from -38% to 26% respectively, Positive and negative heterosis for grain yield of the hybrid rices were observed depending on cross combinations, In the positive heterosis hybrids, number of panicles per hill and number of spikelets per panicle contributed mostly to grain yield, while in the negative heterosis hybrids, spikelet fertility and 1000 grain weight were closely correlated to grain yield. Amylose content of the hybrid rices, maintainer and restorer lines was mostly lower than 20 %, and alkali digestion value was higher than 6.0. Grain appearance of the hybrids tested was similar to the korean japonica rice varieties.