• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.1
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• pp.1-10
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• 1982

Degree of grain shattering which is of varietal character is an important determinant for the magnitude of field loss of grains during harvest and threshing. Seven Indica \times Japonica progeny varieties and four Japonica varieties were subjected to measurements of tensile strength of grains, degree of grain shattering when panicles were dropped at 1.5m above concrete floor, and moisture content of grains (wet basis) during a period 35 to 63 days after heading. In addition, two varieties were tested for the relation of tensile strength of grains to the magnitude of field loss of grains in actual binder harvest. The 11 varieties differed conspicuously in tensile strength of grains and the degree of grain shattering: the weakest average tensile strength of grains of a variety was about 90g and the strongest about 250g with varying standard deviation of 30 to 60g. Three Indica \times Japonica varieties and one Japonica variety shattered I to 30% of the grains under the falling test. The threshold tensile strength of grains allowing grain shattering was estimated to be 180g on average for a sampling unit of 10 panicles, but only the grains having tensile strength weaker than 98g within the samples shattered. A decrease in average tensile strength by 10g below the threshold value corresponded to an increase of 3 to 5% in grain shattering. Most varieties did not change appreciably the tensile strength of grains and degree of grain shattering with delay in time of harvest and showed a negative correlation between the tensile strength and the moisture content of grains. The average tensile strength of grains was negatively correlated linearly with field loss in binder harvest. The average tensile strength for zero field loss in binder harvest was estimated to be 174g and a decrease in the average tensile strength by 10g corresponded to an increase of 40kg per hectare in field loss of grains. Instead of the average tensile strength of grains, the percentage of grains having tensile strength weaker than 100g is recommended as a criterion for the estimation of field loss of grains during harvesting operations as well as a basis of variety classification for grain shattering, since the standard deviation of tensile strength of grains varies much with variety and time of harvest, and individual grains having tensile strength stronger than 98 did not shatter practically.

• Korean Journal of Poultry Science
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• v.34 no.4
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• pp.245-251
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• 2007

This study was conducted to investigate the effects of modification of a herbal recipe(Herb $Mix^{(R)}$) on the growth of pullet and laying performance of hens. The formula of Herb $Mix^{(R)}$, a mixture of Rehmannia glutinosa, Angelica gigas, Discorea japonica, Glycyrrhiza uralensis, Schisandra chinensis and Ligusticum jeholense, was modified in mixing ratio. A total of 1,120 pullets(Hy-Line Brown) of 14 wks old were assigned to seven treatments; control, Herb $Mix^{(R)}$(HM), R. glutinosa fortified HM, A. gigas fortified HM, D. japonica fortified HM, G. uralensis fortified HM, S. chinensis fortified HM, L. jeholense fortified HM and Flavomycin supplemented diet. Each treatment had 8 replicates of 20 birds each housed in 2 birds cages. Body weight at 10% egg production was significantly(P<0.05) influenced by treatments. Birds fed A. gigas fortified HM diet were heaviest followed by L. jeholense fortified HM, HM-original and D. japonica fortified HM, Flavomycin supplemented diet and R. glutinosa while those fed control diet were lightest. Also, age reaching 50% egg production and peak production was earliest in A. gigas fortified HM and latest in the control. Egg production, feed intake, feed conversion and egg weight were significantly influenced by treatments. Significant improvement in egg production and feed intake was shown in A. gigas fortified HM treatment. Feed conversion ratio was lowest in antibiotic(Flavomycin) treatment and egg weight was heaviest in L. jeholense fortified HM treatment. There were no significant differences among treatments in intestinal microflora but cfu of Cl. perfringnes and E. coli tended to be lower in HM treatments than the control. Among the leucocytes of blood, the HM treatments were lower than the control in counts of white blood cell and heterophils. It was concluded that modification of Herb $Mix^{(R)}$ fortifying with A. gigas, D. japonica and L. jeholense significantly influence growth and laying performance of birds.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.6
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• pp.477-484
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• 1984

The crude lipid contents in meat, skin and viscera of eel were 24.94, 20.00 and 14.96, respectively, and higher than the other fresh water fishes. The free lipid was consisted in order of neutral lipid(86.71~94.94), phospholipid(4.13~12.74) and glycolipid(0.63~1.22), and the bound lipid in order of phospholipid(51.74~75.21), neutral lipid(14.41~36.82) and glycolipid(5.12~7.51). The neutral lipid in free lipid was mainly consisted of TG(68.51~95.22), and that in bound lipid TG(36.54~39.94), ES & HC(17.20~18.01), and MG(15.81~18.11). The phospholipid in free lipid was mainly consisted of PC (32.40~56.08) and PE(18.71~31.09), while that in bound lipid PC (<42.51~67.90) and PS (23.37~34.49). The contents of major fatty acid of polar lipid in free and bound lipids were $C_{16:0}$(16.58, 14.10, $C_{18:0}$(12.44, 7.36), $C_{18:1}$(16.01, 15.78), $C_{20:4}$(10.01, 6.11) $C_{20:5}$(4.20, 8.67) and $C_{22:6}$(10.26, 18.32) and those of nonpolar lipid in free and bound lipids were $C_{16:0}$(22.31, 18.61), $C_{18:0}$(4.36, 5.69, $C_{18:1}$(36.30, 27.20) $C_{20:5}$(2.88, 2.38) $C_{22:5}$(6.38, 5.11) and $C_{22:6}$(1.20, 5.11). The total essential fatty acid(TEFA) content of polar lipid in meat was ranged from 17.33 to 22.88, and 2.0~3.0 times higher than that of nonpolar lipid, and the TEFA content of bound lipid in meat was ranged from 11.54 to 22.88, and 1.5~2.0 times higher than that of free lipid. The w3 highly unsaturated fatty acid(w3-HUFA) content of polar lipid in meat was ranged from 8.63 to 42.85, and higer than 11.48 to 14.42 of nonpolar lipid. Also the w3-HUFA content of bound lipid in meat was ranged from 13.35 to 42.85, and higher than 11.48 to 18.63 of free lipid. The w3-HUFA content in meat was higher than that in skin and/or viscera

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47
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• pp.15-32
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• 2002

The endeavors enhancing the grain quality of high-yielding japonica rice were steadily continued during 1980s-1990s along with the self-sufficiency of rice production and the increasing demands of high-quality rices. During this time, considerably great progress and success was obtained in development of high-quality japonica cultivars and quality evaluation techniques including the elucidation of interrelationship between the physicochemical properties of rice grain and the physical or palatability components of cooked rice. In 1990s, some high-quality japonica rice cultivars and special rices adaptable for food processing such as large kernel, chalky endosperm, aromatic and colored rices were developed and its objective preference and utility was also examined by a palatability meter, rapid-visco analyzer and texture analyzer, Recently, new special rices such as extremely low-amylose dull or opaque non-glutinous endosperm mutants were developed. Also, a high-lysine rice variety was developed for higher nutritional utility. The water uptake rate and the maximum water absorption ratio showed significantly negative correlations with the K/Mg ratio and alkali digestion value(ADV) of milled rice. The rice materials showing the higher amount of hot water absorption exhibited the larger volume expansion of cooked rice. The harder rices with lower moisture content revealed the higher rate of water uptake at twenty minutes after soaking and the higher ratio of maximum water uptake under the room temperature condition. These water uptake characteristics were not associated with the protein and amylose contents of milled rice and the palatability of cooked rice. The water/rice ratio (in w/w basis) for optimum cooking was averaged to 1.52 in dry milled rices (12% wet basis) with varietal range from 1.45 to 1.61 and the expansion ratio of milled rice after proper boiling was average to 2.63(in v/v basis). The major physicochemical components of rice grain associated with the palatability of cooked rice were examined using japonica rice materials showing narrow varietal variation in grain size and shape, alkali digestibility, gel consistency, amylose and protein contents, but considerable difference in appearance and texture of cooked rice. The glossiness or gross palatability score of cooked rice were closely associated with the peak, hot paste and consistency viscosities of viscosities with year difference. The high-quality rice variety "IIpumbyeo" showed less portion of amylose on the outer layer of milled rice grain and less and slower change in iodine blue value of extracted paste during twenty minutes of boiling. This highly palatable rice also exhibited very fine net structure in outer layer and fine-spongy and well-swollen shape of gelatinized starch granules in inner layer and core of cooked rice kernel compared with the poor palatable rice through image of scanning electronic microscope. Gross sensory score of cooked rice could be estimated by multiple linear regression formula, deduced from relationship between rice quality components mentioned above and eating quality of cooked rice, with high probability of determination. The $\alpha$-amylose-iodine method was adopted for checking the varietal difference in retrogradation of cooked rice. The rice cultivars revealing the relatively slow retrogradation in aged cooked rice were IIpumbyeo, Chucheongyeo, Sasanishiki, Jinbubyeo and Koshihikari. A Tonsil-type rice, Taebaegbyeo, and a japonica cultivar, Seomjinbyeo, showed the relatively fast deterioration of cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogradation and much sponginess in cooled cooked rice. Also, the rice varieties exhibiting less retrogradation in cooled cooked rice revealed higher hot viscosity and lower cool viscosity of rice flour in amylogram. The sponginess of cooled cooked rice was closely associated with magnesium content and volume expansion of cooked rice. The hardness-changed ratio of cooked rice by cooling was negatively correlated with solids amount extracted during boiling and volume expansion of cooked rice. The major physicochemical properties of rice grain closely related to the palatability of cooked rice may be directly or indirectly associated with the retrogradation characteristics of cooked rice. The softer gel consistency and lower amylose content in milled rice revealed the higher ratio of popped rice and larger bulk density of popping. The stronger hardness of rice grain showed relatively higher ratio of popping and the more chalky or less translucent rice exhibited the lower ratio of intact popped brown rice. The potassium and magnesium contents of milled rice were negatively associated with gross score of noodle making mixed with wheat flour in half and the better rice for noodle making revealed relatively less amount of solid extraction during boiling. The more volume expansion of batters for making brown rice bread resulted the better loaf formation and more springiness in rice breed. The higher protein rices produced relatively the more moist white rice bread. The springiness of rice bread was also significantly correlated with high amylose content and hard gel consistency. The completely chalky and large grain rices showed better suitability far fermentation and brewing. The glutinous rice were classified into nine different varietal groups based on various physicochemical and structural characteristics of endosperm. There was some close associations among these grain properties and large varietal difference in suitability to various traditional food processing. Our breeding efforts on improvement of rice quality for high palatability and processing utility or value-adding products in the future should focus on not only continuous enhancement of marketing and eating qualities but also the diversification in morphological, physicochemical and nutritional characteristics of rice grain suitable for processing various value-added rice foods.ice foods.

• 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.

• Korean Journal Plant Pathology
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• v.3 no.3
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• pp.174-179
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• 1987

Four thousand eight hundred and eighty five isolates of Pyricularia oryzae were obtained from the diseased rice specimens collected from various areas of Korea for race identification during 1978 - 1985. A total of 15 races inculding 6 races pathogenic to Tongil lines, 2 T-races, 5 C-races and 2 N-races was identified using a old Japanese differential set during 1978-1980. Since 1981, number of races identified by a Korean differential set was 18 races which were composed of 11 KI-races pathogenic to either Tongil lines or Japonica cultivars and 8 KJ-races pathogenic to only Japonica cultivars. The prevalent race was $N-2^{+t}$ during 1978-1979 and race KJ-301 since 1980, respectively. Races KI-315a and KI-315b pathogenic to most of Tongil lines were identified in 1983. being widely distributed to date. Races KJ-105 and KJ-201 pathogenic to the cultivars possessing resistance genes Pi-k and Pi-i were prevalent in Gangweon province, whereas race KI-315b was prevalent in Chungbug and Jeonnam districts.

• Applied Microscopy
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• v.15 no.1
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• pp.31-58
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• 1985

The morphological study on different types of cells of reproductive organ including spermatogenesis in the adult planaria was performed to observe their cytochemical and ultrastructural characteristics. 1. Spermatogenesis The circular luminated material appears immediately inside the nuclear envelope of early spermatid and is found also in the nucleus of sperm, but typical acrosomal structures cannot be observed. Approximately ten of small-sized mitochondria occur around the nucleus in the transitional phase from primary spermatocyte to secondary spermatocyte, but in sperm a long mitochondrion is closely associated with nucleus, parellel to long axis of it. The sperm has a relatively long head connected with two tails via hollow neck. 2. Reproductive organ The penis bulb and the bursa stalk were observed. (1) Penis bulb The cells constituted penis bulb are classified into six types on the basis of ultrastructure of the cells and cytochemistry of the cytoplasmic granules. 1) A-type cells: These cells exhibiting low electron density are mainly occupied by large nucleus. These cells possess two different types of granules: highly electron-dense round granules with an average size of $0.9{\mu}m$, and electron-dense granules exhibit PAS-positive reaction. 2) B-type cells contain PAS-positive granules with the size of about $0.4{\mu}m$. They are rich in free ribosomes and mitochondria. 3) C-type cells are found to be dark cells due to high electron-density. These cells are largely occupied by large nucleus. 4) D-type cells: These cells are seen as light cells which have poorly developed cell organelles. 5) E-type tells: These cells contain a large number of glycogen granules which occupy most of cell. 6) F-type cells: These arc parietal epidermal cells surrounding the genital antrum. These cells are characterized by their finger-like shapes and the presence of a number of electron-dense, irregularly-shaped structures inside cells. The relatively large electron-lucent granules can be also found. The F-type cells possess numerous microvilli on their free surfaces. (2) Bursa stalk The cells constituted bursa stalk are classified into 3 types on the basis of cell shapes and presences of electron-dense or electron-lucent granules. 7) G-type cells with a long cytoplasmic process. They have large nuclei and poorly developed cell organelles. 8) H-type cells: These cells are characterized by the presence of a long cytoplasmic process and relatively highly electron-dense cytoplasmic profile. They have poorly developed cell organelles. 9) I-type cells contain large electron-lucent granules which exhibit negative reactions with three kinds of cytochemical staining methods used in this experiment. The fine electron-dense structures can be found inside these granules.

• Journal of Practical Agriculture & Fisheries Research
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• v.22 no.2
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• pp.51-58
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• 2020

Continuous mortality in commercially cultured Japanese eel (Anguilla japonica), showing symptoms of dermal ulcerations and focal hemorrhages on the body, occurred on a private farm in November, 2019 in Korea. A series of mortality had been described in one local eel culture farm from November to December in 2019. From the three cases, three isolates of Vibrio spp. were recovered from the blood, ascitic fluid, and kidney of the dead fish, respectively. Based on the 16S rRNA sequence comparisons, the Vibrio isolates from the 1^st and 3^rd cases (strain named 1E1-2 and 3K1-2) were identified as V. fluvialis and the isolate from the 2^nd case was identified as V. plantisponsor (strain named 2A3-1). Moreover, the 16S rRNA-based phylogenetic analysis revealed that strain 1E1-2 and 3K1-2 were most similar to V. fluvialis NBRC 103150^T, and strain 2A3-1 was most similar to V. plantisponsor NBRC103148^T. According to the results of the antibiotic resistance determination, V. fluvialis 1E1-2 showed intermediate resistance to tetracycline and chloramphenicol, and was resistant to trimethoprim-sulfamethoxazole. V. plantisponsor 2A3-1 showed intermediate resistance to ciprofloxacin and levofloxacin, and was resistant to trimethoprim-sulfamethoxazole. V. fluvialis 3K1-2 showed intermediate resistance to tetracycline, and was resistant to ampicillin and trimethoprim-sulfamethoxazole. These results have provided the evidences on the occurrence of antibiotic-resistant Vibrio infection in commercially cultured Japanese eels are present in Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.3
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• pp.305-309
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• 1983

To know the effect of desaltation in the reclaimed tidal fields on the succession of vegetation and on the root hair formation of paddy rice, reclaimed fields in Kang Hwa Island, Nam-Yang Bay and Ke-Hwa Island were investigated during summer crop season in 1982. The obtained results can be summarized as followings. l) In the highly salty and water logged areas of reclaimed tidal fields, the first dominating species of higher plant were observed to be Salicornia herbacea L. and Suaeda japonica Makino. With the continued desaltation, Chemopodium virgatum Thumb. occurred in the vegetation. After this transition, the dominating species were composed of Scirpus maitimus L. and Phragmites communis Trin. At the S. maitimus and P. communis dominating salinity level, rice cultivation was safe from the salt damage. 2) In the water logged area, Artemisia capillaria Thunb. and Aster tripolium L. took the place of dominating species after S. herbacea and S. japonica. At this salinity level, graminaceous weeds began to immigrate. 3) In dry areas, Suaeda asparagoides Makino and Suaeda maritima were the first appearing dominant species. Atriplex subcordata Kitakawa was also observed in sucy dry areas, but colony formation was not observed. 4) Plants immigrated slowly into dry areas from the already vegetated water logged areas with the continuation of desaltation. 5) The high soil salinity level affected the root hair formation of rice by reducing both the rate of root hair formation and the length of root hairs.

• Journal of Nutrition and Health
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• v.31 no.9
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• pp.1377-1384
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• 1998

The purpose of this study was to investigate the effect of H$_2$O fraction of Dioscorea japonica Thunb(DJT) with selenium(Se) treatment on blood glucose and lipid metabolism in streptozotocin(STZ)-induced diabetic rats. Male Sprague-Dawley rats(180-220g) weighing were divided into five groups, that is one normal group and four diabetic experimental groups : the STZ-control group, the DJT group, the DJT-Se group and the Se group. Diabetes mellitus was induced in the male rats by injection of STZ into the tail vein at a dose of 45mg/kg B.W. The H,0 fraction of DJT(500mg/kg) given orally were administered for 14 days. The Se treated group were fed a AIN-76 recommendation diet mixed with Na$_2$SeO$_3$(2mg/kg diet), which was prepared fresh daily. The body weight and food intake was monitored daily and plasma levels of glucose, insulin, hematocrit and protein were determined. The plasma concentrations of cholesterol, HDL-cholesterol, triglyceride and fire fatty acid were measured. The activities of aminotrans ferase were analysed. The body weight gain was shown to be significantly higher in the normal group than all diabetic groups. The blood glucose levels of the DIT-Se group was significantly lower compared to those of the experimental groups. The administration of H$_2$O fraction of DJT and selenium showed an increase in plasma protein concentrations. The plasma cholesterol levels of all STZ-groups were not significantly different and HDL-cholesterol levels were increased in the diabetic experimental groups fed on H$_2$O fraction of DJT or Se supplementation. Plasma triglyceride levels were lower in the DJT-Se and Se group than in the STZ-control group. free fatty acid levels were not significantly differ among STZ-control groups. STZ treatment increased aminotransferase activity and that of DJT group was highest. In conclusion, the data from the present experiments indicate that the treatment of the H$_2$O fraction of DJT with selenium showed a synergistic effect and the two can have an influence on hyperg1ycemia and lipid metabolites when administered together. (Korean J Nutrition 31(9) : 1377-1384, 1998)