• Proceedings of the Korean Society of Crop Science Conference
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• 2000.04a
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• pp.242-243
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• 2000

• Proceedings of the Korean Society of Crop Science Conference
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• 1999.05a
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• pp.31-32
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• 1999

• Korean Journal of Agricultural Science
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• v.39 no.1
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• pp.9-15
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• 2012

The study was conducted to evaluate the genetic similarity among commercial japonica rice varieties in Korea and China and to develop markers to differentiate between japonica cultivars developed in Korea and China. The genetic similarity and cluster of 38 accessions were analyzed using 47 SSR(simple sequence repeat) markers. The number of alleles by 47 SSR markers ranged from 2 to 9 with an average of 3.6. A total of 169 alleles were detected among these tested rice varieties. The PIC value varied from 0.05 to 0.79 with an average of 0.44. The Chinese japonica cultivars could be differentiated from the japonica cultivars in Korea by combining 2 SSR markers, RM223 and RM266. Cluster analysis showed that 38 tested varieties could be distinguished into japonica and indica based on the genetic distance.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.2
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• pp.155-162
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• 1989

This experiment was conducted to investigate the endosperm characteristics of an opaque rice which was derived from an Indica cultivar Pokhareli Mashino. Grain apperance of opaque rice looked similar to the waxy grain, while the blue-color response to the iodine solution was similar to non-waxy endosperm. The shape of starch granules was alike each other, but their size were different each other with the smallest of the opaque rice. Their cristaline structure of starch granules were A type. The content of total protein and most of the amino-acids of opaque rice was about 1.5 times of other varieties. Alkali digestibility of the opaque rice was very low. Total water uptake and hydration rate of opaque rice was similar to non-waxy variety Tongil. Amylogram characteristics such as viscosity, setback and consistency of opaque rice revealed medium value between. waxy and non-waxy rice.

• Korean journal of applied entomology
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• v.4
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• pp.51-54
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• 1965

The study was initiated to investigate the nature of varietal resistance to the rice stem borer (Chilo suppressalis WALKER), specially the rotation of the resistance to the silica and nitrogen content of the host Plants. 1. The body freight of the larvae, reared on the stem of the various varieties of rice plants, when weighed at the age of 25 days old, showed great variation, and ranged from 21.24 mgrs. to 45.77 mgrs. depending on the used varieties of tile rice plants. And generally the varieties of Indica types were showed greater body weight than that of Japonica types in this experiments. 2. The positive correlation coefficients of percent survivals to body weight, developement, oviposition preference and rate of damage to host plants were significant, and consequently the percent survival could be used as a criteria of resistance. 3. The content of silica in the host plants was significantly correlated with both the degree of boring on the leaf and attractovemess of larvae, and the total nitrogen content of plants showed significant positive correlation coefficient with larval attractivenes, but not significant with the degree of boring on the leaf. 4. Since the attractiveness and boring manner were significantyly correlated to resistance criteria of rice plant to the pest, it could be considered that the resistance is the results of chain reaction of the factors mentioned above.

• Journal of Biosystems Engineering
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• v.11 no.2
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• pp.55-65
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• 1986

The resistance to the passage of airflow through various agricultural products is an important consideration in the design of an aeration or drying system. The amount of resistance to airflow varied widely from one kind of grain to another, and depended upon airflow rate, surface texture and shape of the particles, the size and configuration of voids, and foreign and fine material in the grain bed. The airflow rate was the major factor considered on this kind of study in the early stages. But these days, the studies on the resistance to airflow of grain affected by grain moisture content and foreign and fine material have been widely carried out. However the foreign an fine material in the grain bed could not be a major factor on the study in Korea because there were only a few grain process procedure after harvesting it. The objectives of this study were to investigate the effect of moisture content and airflow rate on airflow resistance to grain, and to develop a model to predict the static pressure drop across the grain bed as a function of moisture content and airflow rate. The rough rice varieties, Akibare, Milyang 15 (Japonica types), Samkwang, Backyang (Indica types)and covered barley variety, Olbori, which were harvested in 1985 were used in the experiment after cleaning them. Resistances to airflow of grain were investigated at four levels of moisture content (13-25%, wb.) for ten different airflow rates($0.01-0.15m^3/sm^2$). The results of this study are summarized as follows; 1. Theaverage bulk densities were $585.3kg/m^3$ for rough rice and $691.6kg/m^3$ for barley at the loose fill, and were $648.8kg/m^3$ for rough rice and $758.2kg/m^3$ for barley at the packed fill. The pressure drops at the packed fill beds were approximately 1.4 to 1.8 times higher than those at the loose fill beds. 2. The pressure drops across grain beds deceased with the increase of moisture content and increased with airflow rate. The decreasing rates of pressure drop across grain beds according to the moisture contents at the lower airflow rates were higher than those at the higher airflow rates, and the increasing rates of pressure drop according to the airflow rates at the lower moisture contents were higher those at higher moisture contents. 3. The pressure drop across barley bed were much higher than rough rice beds and the pressure drops across Japonica type rough rice beds were a little higher than Indica type. 4. The mathematical models to predict the pressure drop across grain beds as a function of moisture content and airflow rate were developed from these experiments.

• Applied Biological Chemistry
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• v.26 no.1
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• pp.65-72
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• 1983

The composition of four rice protein groups is greatly affected by the extraction conditions. The extraction amounts of albumins and glubulines primarily depended on the temperature rather than the method of extraction. The total amount of glutelins, the major components of rice storage proteins, could be extracted by a successive extraction processes, extraction with 0.5% SDS-0.1M borate buffer(pH 8.3) followed by extraction with 0.5% SDS-0.6% ${\beta}-mercaptoethanol-0.1M$ borate buffer(pH 8.3). The extracted amounts of glutelin with these solvents were 54.1 and 45% respectively. The further purification of SDS soluble glutelins was achieved by Sephadex G-150 gel column chromatography. The molecular weight of the components in four protein groups has been estimated by SDS-polyacrylamide gel electrophoresis with or without ${\beta}-mercaptoethanol.$ The comparison of albumins and globulins by starch gel electrophoresis at pH 3.1 permitted us to identify seven rice varieties. However, at pH 8.95, the specific bands for Japonica type rice varieties were observed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.3
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• pp.229-234
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• 1982

Environmental factors are known in general to influence much on the development of abscission layer and thereby on shedding of plant parts. The present study was carried out to determine the effect of meterological condition during ripening on the grain shatterability of rice plants at harvest. Different meteorological conditions were obtained by shifting transplanting timing of 40 days old rice seedlings 4 times with a 15 days-interval. Grain shatterability was measured as tensile strength of rice grains: it varied within a range of 214g. to 251g. in a practically non-shattering Japonica variety'Jinheung' and l27.5g. to 204g. in an easy shattering Indica \times Japonica progeny variety'Taeback'. In view of field loss of rice, the variation in tensile strength with time of transplanting and harvest did not matter in Jinheung, but was an important factor in Taeback. In Taeback the tensile strength was significantly correlated positively with mean, maximum and minimum air temperature and relative humidity during a certain period of grain ripening, especially during 30 days period before harvest, but diurnal range of air temperature showed a significant, negative correlation with it. The tensile strength seemed to be more closely related with min. air temperature than max. air temperature, and it was not significantly correlated with radiation amount during any period of pre-harvest. Meteorological effect on grain shatterability may vary with variety, but temperature regime during ripening appears to play major role among the meteorological factors in easy shattering and more thermophilic Indica \times Japonica varieties: lower the temperature, greater the shatterability.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.4
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• pp.329-341
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• 2011

The objective of this study was to determine the genetic diversities of major rice blast resistance genes among 84 accessions of aromatic rice germplasm. Eighty four accessions were characterized by a dominant 11 set of PCR-based SNP and CAPS marker, which showed the broad spectrum resistance and closest linkage to seven major rice blast resistance (R) genes, Pia, Pib, Pii, Pi5 (Pi3), Pita (Pita-2), and Pi9 (t). The allele specific PCR markers assay genotype of SCAR and STS markers was applied to estimate the presence or absence of PCR amplicons detected with a pair of PCR markers. One indica accession, Basmati (IT211194), showed the positive amplicons of five major rice blast resistance genes, Pia, Pi5 (Pi3), Pib, Pi-ta (Pi-ta2), and Pik-5 (Pish). Among 48 accessions of the PCR amplicons detected with yca72 marker, only five accessions were identified to Pia gene on chromosome 11. The Pib gene was estimated with the NSb marker and was detected in 65 of 84 accessions. This study showed that nine of 84 accessions contained the Pii gene and owned Pi5 (Pi3) in 42 of 84 accessions by JJ817 and JJ113-T markers, which is coclosest with Pii on chromosome 9. Only six accessions were detected two alleles of the Pita or Pita-2 genes. Three of accessions were identified as the Pi9 (t) gene locus.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.1
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• pp.86-94
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• 1999

A set of rice recombinant inbred lines was developed from a cross between a Tongil type variety, Nonganbyeo, and an indica variety, BG276, by the single seed descent method. The number of the lines in the population was 272. All the agronomic characters studied except ADV (alkali-digestion value) showed continuous variation among the RILs, implying that their inheritance mode should be quantitative. The patterns of the variation in the RILs were either normal or skewed distribution. ADVs of RILs were segregated into two groups with 1:1 ratio, indicating that ADVs in this KIL population might be controlled by one major gene. Transgressive variations were also observed in all characters. Heritability values of the characters varied from 0.488 in brown/rough rice ratio to 0.895 in alkali-digestion value. In the analysis of genotypic and phenotypic correlations, the character of yield was positively correlated with 8 different agronomic characters. The number of panicles per hill was negatively correlated with culm length, panicle length, and number of spikelets per panicle. Grain length was positively correlated with grain width, grain thickness, grain length/width ratio, white belly, ADV, and amylose. However, grain length/width ratio was negatively correlated with grain width. White core was also negatively correlated with white belly and ADV.