• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.1
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• pp.26-31
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• 1999

This experiment was conducted to evaluate genetic variation in 48 rice accessions (Oryza sativa L.) using AFLP and RAPD markers. For AFLP, a total of 928 bands were generated with 11 primer combinations and 327 bands (35.2%) of them were polymorphic among 48 accessions. In RAPD analyses using 22 random primers 145 bands were produced, and 121 (83.4%) were polymorphic among 48 accessions. Each accession revealed a distinct fingerprint by two DNA marker systems. Cluster analysis using AFLP-based genetic similarity tended to classify rice cultivars into different groups corresponding to their varietal types and breeding pedigrees, but not using RAPD-based genetic similarity. The AFLP marker system was more sensitive than RAPD in fingerprinting of rice cultivars with narrow genetic diversity.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.331-331
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• 2017

This study was conducted to know the influence of air temperature and sunshine duration on yield, chemical component, pigment color difference and starch characteristics of two colored rice cultivars in the plain area of Yeongnam province in Korea. The $L^*$, $a^*$, and $b^*$ value of brown rice in Hongjinju and Josaengheugchal rice cultivars was significantly different at continuous cultivated years, 2015 and 2016. The $L^*$, $b^*$ value of two colored rice was significantly increased in 2016 compared to 2015. The $a^*$ value of Josengheugchal rice cultivar was also significantly higher at 2016 than at 2015. It can be noticed the $a^*$, $b^*$, $L^*$ values in Josaengheugchal varied more than those in Hongjinju. Air temperature during ripening period in 2016 was higher than 2015, especially minimum temperature was too high to proper maturation for rice quality. In Josaengheugchal rice cultivar, sunshine duration after heading was longer in 2016 than in 2015. On the contrary, Hongjinju rice cultivar was ripened under condition of insufficient sunshine duration in 2016. The short growing duration by high temperature and long shiny duration made the lack of pigment for Josaengheugchal brown rice. In Hongjinju rice cultivar, shorten sunshine duration and higher night temperature were the source of the pigment deficiency. The grain size of rice which produced in 2016 was bigger than that of 2015 in both rice cultivars. The 1,000 grain weight of rice from 2016 was also bigger than that of 2015. Head rice ratio was high in the rice cultivars produced in 2015. Protein of milled rice in 2016 was more decreased than that of 2015 in Josaengheugchal rice cultivar, it showed reverse result in Hongjinju rice cultivar. Amylose contents of milled rice in 2016 were more decreased than that of 2015 in Hongjinju rice cultivar. Branch chain length distribution of amylopectin was shown a distinct difference between Josaengheugchal and Hongjinju rice flours by each produced year. Josaengheugchal rice cultivar produced in 2015 had a higher amount of short chains than that of 2016 rice starches. In Josaengheugchal rice cultivar, the pasting temperature and peak, trough, breakdown, final viscosity increased in rice flour which produced at 2016, whereas the setback viscosity and peak time showed lower value than those of rice from 2015. The most pasting properties (except of setback viscosity) of rice starch in Hongjinju rice cultivar grown in 2015 were higher than those of rice cultivar produced in 2016.

• Research in Plant Disease
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• v.19 no.4
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• pp.243-253
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• 2013

Rice blast is one of the most serious disease threatening stable production of rice. Breeding of resistant cultivars has been used as the most effective and useful method to controll rice blast caused by Magnaporthe oryzae. To collect rice blast isolates in fields and test their pathogenicity on new cultivars are important for establishment of new resistant cultivars breeding program of rice. Pathotypes of Korean rice blast isolates have been categorized to Korean differential race system developed in 1985. However, it is little known about genetic background of Korean differential cultivars, so that it is hard to understand for relationship between each pathogen and each host plant at genetic level. In this study, we suggested necessity of a new differential system by analyzing pathogenic responses between 24 monogenic rice lines and 200 Korean rice blast isolates. In addition, we determined the nine representative resistant genes based on the resistance responses of the monogenic lines to rice blast isolates, indexed resistant responses of the monogenic lines to ten representative rice blast isolates and selected 30 Korean representative rice blast isolates proper to Korean system. We think the newly developed differential race system can be broadly used to select resistant cultivars to rice blast in Korea.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.330-330
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• 2017

The tallest culm length was observed in Geonganghongmi cultivar grown in coast area, and culm length was always taller in coast area than that of inland area among these three red rice cultivars. However, number of tiller per rice plant was not affected by different cultural area. Number of spikelets per panicle was much more increased in inland area. Regional difference in number of spikelets per panicle was only observed in Jeongjinju cultivar. Among these red rice cultivars, the highest brown rice yield was Jeongjinju rice cultivar having 702kg in inland area and 692kg in coast area, respectively. The $L^*$ values, which expresses the brightness, were in the range of 36.3 ~ 36.7, 36.7 ~ 37.0, and 38.7 ~ 39.6 in Jeogjinju, Hongjinju, Geonganghongmi rice cultivars, respectively. The $a^*$ values, which expresses the redness positively and greenness negatively were in the range of 12.3 ~ 12.8, 12.2 ~ 12.3, and 12.1 ~ 11.9 in Jeogjinju, Hongjinju, Geonganghongmi rice cultivars, respectively. In addition, the b values, which expresses the yellowness positively and blueness negatively were in the range of 13.8 ~ 14.0, 13.6 ~ 13.5, and 14.9 ~ 14.7 in Jeogjinju, Hongjinju, Geonganghongmi rice cultivars, respectively. Anthocyanidin content ranged 524 to $610{\mu}g/g$ dry weight basis. Cyanidin content was 11.4 to 14.0 times higher than that of delphinidin under coast and inland area. Among these rice cultivars, anthocyanidin content was always higher in rice cultivar grown at coast area. Highest head brown rice rate was only observed in Geonganghongmi to 95.2 at coast area and 95.4 inland area, respectively. Protein content was always higher in coast area than that of inland area. The lowest protein content was measured in Jeogjinju and amylose content was relatively increased in inland area compared to that of coast area. Consequently, in considered with brown rice yield and pigment content, Hongjinju rice cultivar was recommended in optimal pigment rice cultivar in eastern coast of Gyeongsangbuk-do Province.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.2
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• pp.108-112
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• 2003

Foehn damage on rice plant is one of the important abiotic stresses in eastern costal area of Korea. To know the relationship between foehn impact and morphological traits of rice, wind tunnel method was used with 106 rice cultivars. Less influencing traits on foehn were short panicle, large panicle number per hill, thin panicle neck, and the flag leaf of narrow, short and thick. Leaf pubescence reduced the impact on foehn. 'Naepungbyeo' belong-ed to foehn tolerant varietal group, while 'Ansanbyeo' belonged to the opposite group. Three levels of root cutting treatment with two rice cultivars were conducted to evaluate the foehn impact using wind tunnel. The severity of wind damages was followed the sigmoidal curve duration of wind tunnel treatment were prolonged. Different responses of root cutting to wind tunnel treatment could be used to evaluate the severity of the foehn impact. 'Naepungbyeo' was one of the less implausible cultivars on foehn. 'Nae-pungbyeo' showed tolerant response to wind under 21% root removing treat-ment (20㎝ root cutting), however 'Ansanbyeo' was wilted under the same treatment. In case of 35 % root removing treatment(10㎝ root cutting), both rice cultivars failed to alive against foehn wind.

• Applied Biological Chemistry
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• v.46 no.2
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• pp.117-122
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• 2003

Starches from 4 rice cultivars, including Whachungchalbyeo and Whachungbyeo, together with two correspondiug conversion mutants with giant embryonic phenotype, Whachungchal-giant embryonic rice and Whachung-giant embryonic rice, were isolated to compare its physico-chemical properties. The amylose content and the length of glucose chains in the fractionated amylose was reduced in response to conversion of the rice cultivars for developing giant embryonic phenotype. For the fine structure of amylopectin, conversion to giant embyonic rice cultivars accompanied with slight increase in the length of B chain plus decrease in the amount of A chain, and also a slight increase in average glucose chains length of amylopectin fractions could be observed. X-ray diffractogram revealed 4 cultivars to be the representative A types. We could also obtain the results that the hydrolysis rate by glucoamylase in the waxy rice cultivars decreased in response to conversion to the giant embryonic rice cultivars, while the rate increased in the non-waxy rice cultivas. Termination temperature for gelatinization was observed to decrease in response to conversion into the giant embryonic rice cultivars, however, the enthalpy for gelatinization was found to increase with the same conversion process.

• Plant Breeding and Biotechnology
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• v.2 no.3
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• pp.224-230
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• 2014

Amplified fragment length polymorphism (AFLP) is a molecular marker technique based on DNA and is extremely useful in detection of high polymorphism between closely related genotypes like Korean wheat cultivars. Six sequence characterized amplified regions (SCARs) have been developed from inter simple sequence repeat (ISSR) analysis which enabled the identification and differentiation of 13 Korean wheat cultivars from the other cultivars. We used six combinations of primer sets in our AFLP analysis for developing additional cultivar-specific markers in Korean wheat. Fifty-eight of the AFLP bands were isolated from EA-ACG/MA-CAC, EA-AGC/MA-CTG and EA-AGG/MA-CTA primer combinations. Of which 40 bands were selected to design SCAR primer pairs for Korean wheat cultivar identification. Three of 58 amplified primer pairs, KWSM006, KWSM007 and JkSP, enabled wheat cultivar identification. Consequently, 23 of 32 Korean wheat cultivars were classified by eight SCAR marker sets.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.225-225
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• 2022

Rice is a major food crop consumed by approximately half of the world's population. Heading date is one of the major agronomic traits and has a wide impact on the productivity and quality of rice. Recently, shortening the growth period of rice through modulating heading date has been emphasized as one of the most effective strategies for reducing methane emissions from paddy fields. OsPRR37, a major heading date gene in rice, represses flowering under both short-day and long-day conditions. Plants carrying the loss-of-function alleles of OsPRR37 have been reported to flower approximately seven days and 20 days earlier than those carrying the functional alleles in short day and long day conditions, respectively. In this study, we investigated the nucleotide sequence variation existing in the exonic regions of OsPRR37 and catalogued the allelic distribution in 208 Korean rice cultivars. We used four sets of primers for amplifying and sequencing the eight exons of OsPRR37. As a result, two types of loss-of-function alleles and four types of functional alleles were found in 208 Korean rice cultivars. Interestingly, only three cultivars (Jinbuolbyeo, Jinseolchal, and Mimyeon) carried loss-of-function alleles while 205 carried functional alleles, indicating that OsPRR37 loss-of-function alleles have been used very rarely in Korean rice breeding programs. To generate useful information for the development of early-maturing rice cultivars, our future work will focus on analyzing the effect of different OsPRR37 alleles on heading date and other major agronomic traits.

• The Korean Journal of Food And Nutrition
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• v.30 no.6
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• pp.1260-1267
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• 2017

The properties of rice were studied on five rice cultivars (Ilpumbyeo, Samkwang, Goami-4, Dodamssal, and Thai rice), and employed two kinds of saccharification treatment methods (treatment I : rice shape, treatment II: grinding rice shape). Thai rice showed differences in width and length when compared to other cultivars of rice, and the Goami 4 had the lowest thousand-grain weight. The Goami4 and Dodamssal each showed high contents of amylose and resistant starch, and the water absorption rate was close to maximum at 90 minutes as well as the highest level of Goami 4 at all times. The qualities of highest water-binding capacity, solubility and swelling power was most significant in Thai rice. The lowest hardness level of wet rice resulted in the lowest hydration-related characteristics. High amylose content rice, in particular, showed low sugar content and slightly increased sugar content as the saccharification process improved (treatment II). On the other hand, high amylose cultivars had the same high degree of hardness as boiled rice. From these results, the Dodamssal was found to have the lowest viscosity at all temperatures but highest viscosity during the saccharification process, suggesting it may be successfully implemented as a thickener in rice beverage processing. The purpose of this study was to attempt to provide basic data on the development of rice beverage manufacturing technology, based upon the quality characteristics related to beverage processing of rice cultivars.

• Current Research on Agriculture and Life Sciences
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• v.7
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• pp.117-125
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• 1989

This study was carried out to investigate the effect of hot water immersion treatment on the control of white tip nematode (Aphelenchoides besseyi) in rice seeds. Disease incidence and yield losses induced by white tip nematode were alos investigated in association with resistance of various rice cultivars. The hot water immersion treatment of rice seeds at $61^{\circ}C$ for 10-15 minutes was effective for the control of the white tip nematode. The stem of most Japonica-type cultivars was damaged by white tip nematode. The Tongil-type cultivars, however, were not infected by the nematode at all. Diseas incidence of Japonica-type cultivars, Odaebyeo and Bogkwangbyeo were 95.6% and 81.8%, respectively. The number of nematodes in infected rice seeds of both Japonica-type and Togil-type cultivars was over 100 per 10gr rice seeds. Although Tongil-type cultivars didn't show white tip symptoms, the yield loss was found in many cultivars. The yield was reduced by 40% Japonica-type cultivars, Odaebyeo and Bogkwangbyeo that were infected by white tip nematode. The yield loss in Japonica-type cultivars was more severe than that in Tongil-type cultiveas. The resistance of Youngdege 5 was highest than any other cultivars showing no disease symptoms and yield loss.