• Proceedings of the Korean Society of Crop Science Conference
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• 1986.06a
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• pp.22-23
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• 1986

• Applied Biological Chemistry
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• v.28 no.3
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• pp.142-148
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• 1985

Pasting properties of 35 traditional (Japonica) and 23 high-yielding (J/Indica) rice varieties having various hydration rates at $23^{\circ}C$ were investigated. Amylograms showed that high-yielding rice varieties had higher values for peak (P), hot-paste (H) and cold-paste (C) viscosities than those for traditional rice varieties. P had a highly negative correlation with H/P, C/P and C/H. P of traditional rice varieties was positively and negatively correlated with protein amylose contents, respectively. However, H and C showed no correlation with protein or amylose content. No correlation was observed between amylograph indices and hydration rate of rice grain.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.269-269
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• 2022

Pre-harvest sprouting (PHS) on rice panicles is getting problematic in recent several years in Korea due to climate changes such as high temperature and more frequent typhoons during harvesting season. PHS negatively affects grain quality severely and also yield. Genetic improvement of Korean varieties (Oryza sativa ssp. japonica) through a marker assisted-backcross breeding (MAB) with the known PHS resistant genes must be one of ideal solutions. However, the final breeding products of MAB occasionally exhibit unwanted traits, especially the cross between genetically distant parents. This might be caused by linkage drag and/or presence of the gene-unlinked donor introgressions, resulting that the final products could not be released to the farmers. The major PHS resistance gene, Sdr4 (Seed dormancy 4) originated from an indica cultivar, Kasalath was selected as a donor gene. In order to avoid unexpected phenotypes in the breeding products, we performed a precision marker-based breeding (PMBB) consisting of foreground, recombinant, and background selections (FS, RS, and BS) which aim to develop 'single small introgression lines' (~100 kb introgression). Korean varieties (Ilpum and Gopum) were crossed with Kasalath. We developed Sdr4-allele specific markers for FS and a set of polymorphic flanking markers near the Sdr4 (-350kb and +420kb) for RS. To minimize linkage drag, the small introgression (< 125kb) containing Sdr4 was selected in Ilpum background (BC₂F₄) through 1^st RS with ~1,200 F₂ or BC₁F₂ plants (one side trimmed) and then 2^nd RS with ~1,000 progenies from the 1^st RS selected plants (another side trimmed). After RS, the selected lines were genotyped by using Infinium 7K SNP chip to detect other donor introgressions and the lines were backcrossed. Currently BS is on-going from the backcross-derived progenies with BS markers to remove residual introgressions. During the PMBB process, genetic effect of Sdr-4-Kasalath allele was confirmed in Ilpum and Gopum backgrounds by PHS phenotyping using the segregating BC₂F₃ or BC₁F₄ materials. The Sdr4 PMBB lines in Ilpum background (< 125kb introgression) will be valuable genetic resources to improve PHS resistance in modem popular temperate japonica varieties.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.1
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• pp.45-53
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• 1992

This studies were conducted to investigate the physiological characteristics of photosynthesis and dry matter accmulation of 2 Tongil type and 2 Japonica type varieties under different temperature and light intensity condition. Photosynthetic activities were lower in Tongil type varieties than Japonica type at low temperature(17$^{\circ}C$), but higher in Tongil type varieties at high temperature in each growth stages. The degradation rate of photosynthesis was higher in Tongil type varieties than Japonica type varieties at low temperature and Tongil type varieties were showed high photosynthetic activities at high temperature ($25^{\circ}C$). Specific Leaf Area in each growth stages were the highest at tillering and increased from panicle formation stage to heading stage. The ratio of respiration to photosynthesis (R /P$\times$200) into upper three leaves were significantly high in third leaf and showed same slope in each varieties. CGR, NAR were higher in Tongil type varieties than Japonica type varieties and yields, havesting index were showed high in Tongil type varieties.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.368-368
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• 2017

Rice is the world's three major crops that is the staple food of Asian. Japonica type rice is consumed in Korea. Rice cultivation area decreases steadily. That is affected by decrease of the farm income with the inventory of 1.7 million tons, which is 2 to 3 times more than the optimal amount due to the decrease in the consumption of rice per person and cultivate high yield varieties. In recent years, as income level has improved, interest in health has been high and consumption for health food has been steadily increasing. For health food, rice is added by adding grains such as millet, sorghum, oats, beans and colored rice rather than white rice. In 1997, RDA(Rural Development Administration) developed black rice 'Heuknambyeo', and then 20 varieties were bred until 2017. In CBARES(Chungbuk Agricultural Research and Extension Services), we have developed new rice varieties 'Cheongpungheukchal' in 2010, 'Cheongpungheukhyangchal' in 2014, 'Cheongpungheukchal' is high in farming preference because of high yield. Black rice has high content of GABA and water-soluble phenol, DPPH radical scavenging activity, and consumers are interested in the function in the body. Therefore, functional and antioxidant activities(anthocyanin, total polyphenol, ${\alpha}-glucosidase$ inhibition) and antioxidant activities(ABTs, DPPH) were analyzed by comparing white and black rice. Testing varieties are 'Chucheongbyeo', best quality cultivars 'Daebo' and 'Samgwang' as white rice which are cultivated much in Chungbuk area, and black rice are 10 varieties including 'Cheongpungheukchal', 'Cheongpungheukhyangchal', 'Josaengheukchal' and so on. It has transplanted on 25th May, at CBARES research paddy by 100% fertilizer recommendation rate. Harvesting time was 50 days after heading by varieties, and has researched growth properties, yield and yield components, functional and antioxidant activities. Anthocyanin content was not measured because there was no pigmented in white rice, the highest value of anthocyanin content was 'Shintoheukmi' and in the range of 125.6~249.6mg/100g by black rice varieties. Total polyphenol content was high 'Cheongpungheukchal' and 'Shintoheukmi' and in the range of 96.68~244.34 mg/100g in black rice, white rice lower than blackish rice at 19.84~22.51mg/100g. ${\alpha}-glucosidase$ inhibition was high 'Cheongpungheukchal', 'Cheongpungheukhyangchal' and 'Shintoheukmi' in the rage of 75.87~98.85% by black rice varieties, especially 'Samgwang' was 80.75% and the other white rice was higher than 58~68%.

• Korean journal of applied entomology
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• v.19 no.4 s.45
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• pp.203-211
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• 1980

The pattern of blast disease incidence of Tonsil-line rice varieties derived from the cross between Indica and Japonica type was quite different from that of Japonica-type rice varieties. The former showed discontinuity between the incidence of leaf blast and panicle blast; the incidence .of leaf blast was slight, while that of panicle blast was very severe. Different level of nitrogen fertilizer applied influenced significantly the incidence of leaf blast but influenced slightly the incidence of panicle blast of Tongil-line rice varieties. The infection percentage of panicle blast of Tongil-line rice varieties was about $90\%$ and most of them were infected in leaf sheaths during booting stage, but infection of panicle blast of Japonica-type rice varieties in leaf sheaths during booting stage was very low, only about $3\%$. Infection route of panicle blast in leaf sheaths during booting stage, microflora in leaf sheaths, and specific susceptibility of young panicle to blast disease were investigated in the epidemiological point of view.

• Korean journal of food and cookery science
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• v.29 no.6
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• pp.785-794
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• 2013

To satisfy the consumer's interest with safety and high quality of staple foods, the physicochemical properties and cooking quality of organic rice using hairy vetch in Korea were compared. Two Korean varieties, Hopyeong and Ilmi, two Japanese varieties, Koshihikari and Hedomebore, and newly developed in Jeonnam, Mipum which cultivated in the same region and conditions were used. Physicochemical properties and cooking quality were investigated. All samples were japonica type short grains and their length/width ranged 1.74-1.84. The protein, ash, and crude lipid contents were significantly different with varieties and the protein content of Korean rice was lower than that of Japanese rice, especially, that of Hopyeong was the lowest. Amylose content and initial pasting temperature were lower in Hopyeong and Japanese rice, but peak viscosities showed reverse trends. Swelling power at $80^{\circ}C$ showed higher in Hopyeong and Koshihikari. Color values, L, a and b were significant difference with varieties and color differences of Hopyeong and Huitomebore were lower than those of others. Texture properties, hardness and adhesiveness of Hopyeong cooked rice showed the lowest values, but adhesiveness of Japanese cooked rice exhibited the highest value. On sensory evaluation of cooked rice, glossiness of Koshihikari, intactness of Koshihikari, Huitomebore, and Hopyeong, stickiness of Koshihikari and Hopyeong showed higher values (p<0.05). The overall quality score of organic cooked rices decreased as following order; Koshihikari> Hopyeong> Huitomebore> Mipum> Ilmi.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.4
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• pp.334-341
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• 1984

Yield response of 30 rice varieties widely grown during the past 70 years in Korea was examined at the six transplanting dates from May 10 to June 29 at the 10 day intervals in 1982. Early japonica varieties grown before 1960s showed the highest yield at the June 9 and 19 transplantings and yields decreased with earlier or later transplantings except the earliest transplanting of May 10. However, yield of recent japonica varieties grown after 1960s was similar among the transplanting dates from May 10 to June 19, but yield was lower at the June 29 transplanting. In the indica/japonica varieties grown after mid- 1970s, yield was highest at the May 10, 20, and 30 transplantings and it decreased with further delay of transplantings largely due to the decreased panicle number, percent ripened grains, and 1,000 grain weight. This may indicate that recently developed varieties may be more adaptable toearly transplanting than older varieties. The number of panicles per hill was variable among the transplanting dates in all varieties, but it decreased as transplanting dates delayed after June 9. In japonica varieties the number of spikelets per panicle, percent ripened grains, and 1,000 grain weight increased as transplanting was delayed. However, in indica/japonica varieties the number of spikelets per panicle was similar among the transplanting dates and percent ripened grains and 1,000 grain weight decreased as transplanting date was delayed after June 9. The percent ripened grains of japonica varieties decreased with increase in the number of spikelets per hill but increased as heading date delayed. However, in indica/japonica varieties the percent ripened grains was not affected by both the number of spikelets per hill and heading date except that of June 29 transplanting of which percent ripened grains was extremely low because of delayed heading although the number of spikelets per hill was low. Grain/Straw ratio was not affected by heading date in japonica varieties, but it decreased significantly as heading date was delayed in indica/japonica varieties.

• Korean Journal of Agricultural Science
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• v.2 no.2
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• pp.331-339
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• 1975

This experiment was carried out to obtain some imformations about the ecological variations of the heading time of the newly breeded Indica x Japonica varieties/pedigrees according to the seasonal changes of the seeding date. day length and temperature. The results obtained are summarized as follows; 1) At all varieties. days to heading showed a straight reduction according as the seeding time was delayed. 2) At the group of Japonica varieties. the days to heading of early maturing varieties were much shortened and that of medium or late maturing varieties were little or not shortened under high temperature condition but at the group of Indica ${\times}$ Japonica va rieties/pedigrees. days to heading were significantly elongated under high temerature condition. 3) At the group of Japonica varieties. the effect of the short day condition on the days to heading was significantly high at the medium and the late maturing varieties than at the early maturing varieties. however. the short day effect on the reduction of days to heading was not related with the earlyness of each varieties at the group of Indica ${\times}$ Japonica varieties/pedigrees. 4) Days to heading of all varieties under the high temperature condition were longer than that under the ordinary culture. On the other hand, the days to heading of Japonica varieties under the short day treatment were shorter than the days to heading of ordinary culture but at the group of Indica x Japonica varieties/pedigrees. the days to heading under the short day treatment were longer than ordinary culture. 5) At both varieties groups. the days to heading at each seeding time were significantly correlated with days to heading at ordinary cultivation. fl) At the group of Japonica varieties. relatively high correlation(p=0.1) was recognized between the days to heading by delay of seeding time, but at the group of Indica ${\times}$ Japonicava rieties/pedigrees, correlation between the ordinary heading date and the shortening rate of days to heading was very low.

• Korean Journal of Agricultural Science
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• v.4 no.1
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• pp.10-20
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• 1977

An expriment was conducted to determine the rate of germination under low temperature and effects of low temperature on seedling of varieties derived from the cross between Indica and Japonica type of rice. Total of 30 varieties including leading variety, Tongil, were germinated at the temperature of $10^{\circ}C$. and $15^{\circ}C$. to determine the rate of germination, and six varieties also including Tongil were planted in pot, and seedlings were exposed to the temperature of $5^{\circ}C$. and $1^{\circ}C$. for 15 days and damage of plant growth due to low temperature was observed. 1. Under the condition of $10^{\circ}C$., varieties such as Iri #323, Suwon #253, Iri #325, Milyang #22, Suwon #251, and Suwon #267 were showing over 70 percent of germination ratio, while varieties, Dodolokiwase, Milyang #23, Yusin, Iri #328, and Iri #329 were below 10 percent in germination ratio. 2. Under the condition of $15^{\circ}C$., variety Suwon #262 was shown 100 percent of germination and varieties such as Milyg an#22, Dodlokiwase, Tongil, Milyang #29, Suwon #258, Milyang #23, Milyang #24, Milyang #28 and Milyang #21 were over 90 percent in germination ratio. However, varieties such as Iri #328, Iri #329, Jinheung, and Minehikari were below 50 percent in germination rate. 3. Considering the germination rate and average days required to germination, Milyang #22 and Iri #323 were highly resistant varieties to low temperature. The rate of germination of varieties from the cross between Indica and Japonica under low temperature was not always lower than that of varieties from Japonica type of rice. 4. Most of the seedlings of varieties used were quite resistant to $1^{\circ}C$. at least for six hours. However, leaves of rice were exposed to the the temperature of $1^{\circ}C$. for 12 hours, and the withered leaves were recovered soon when put in under normal temperature. The degree of leaf withering under low temperature was lower in Milyang #15, Japonica type than in varietieties belonging to $Indica{\times}Japonica$ type of rice. 5. When the seedlings of varieties such as Josaengtongil, Tongil and Yusin were exposed to the temperature of $1^{\circ}C$. for 36 hours, 70 percent of leaves were withered and when the time of expose were doubled, the leaves were completely died. When the temperature was fluctuated, over 75 percent of leaves were died, while 65 percent of leaves of Milyang #15 were died when exposed to $1^{\circ}C$, for 72 hours. 6. Significant growth retardation was observed for all entries when exposed to $1^{\circ}C$. for 24 to 36 hours. The growth retardation was apparently increased as the time of expose was extended.