• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.1
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• pp.97-101
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• 1988

The objective of this paper was to examine the oxygen requriement of rice seeds when the seeds were germinating under the water. The trial was carried out in the laboratory with the different water temperature (25$^{\circ}C$, 17$^{\circ}C$) in the Crop Experiment Station, Suwon. The tested varieties were 6 in japonica and 6 in indica (I) ${\times}$ japonica (J). In the 25$^{\circ}C$ water temperature rice seeds absorbed more dissolved oxygen (DO) and germinating duration was shorter than in the 17$^{\circ}C$ water temperature. DO uptake of japonica rice seeds was faster than that of indica ${\times}$ japonica rice seeds, and the germinating ratio of japonica rice seeds was higher than that of I${\times}$J rice seeds in the water. DO requirements of germinating rice seeds in the water were average 82.4 ${\mu}$g per seed up to coleoptile appearance and average 123.6 ${\mu}$g per seed up to appearance of radicle in the japonica varieties, but I${\times}$J varieties were 96.9 ${\mu}$g and 145.1 ${\mu}$g respectively. Especially when the rice seeds were germinated in the water, length of coleoptile and radicle of japonica rice were significantly longer than those of I${\times}$J rice varieties.

• Preventive Nutrition and Food Science
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• v.4 no.1
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• pp.1-5
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• 1999

Seven rice varietes(Suweonjo, Suweon232 , BG276-5, IR44, IR41999-139, Suweon230 and Yongjubyeo) were used to study the influence of amylose content and particle size on the physicochemical properties of rice flours. Suweonjo has the highest amylose content (27.1% amylose content) had the finest flour particle as supproted by scanning electron microscopy (SEM). Suweonjo had the highest value in hardness of rice grain but the lowest length/width ration. There were no significant differences in color values among the rice flours. Data of brabender visco/amylograph was not associated with amylose content. Yongjubyeo had the highest maximum viscosity and breakdown value while Suweonjo had the lowest maximum viscosity , setback value and breakdown value. Yongjubyeo had the lowest water solubility index (WSI). The Suweon232 rice variety absorbed more water than any other varieties but rice varieties and amylose contents affected water absorption a little.

• Korean journal of applied entomology
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• v.14 no.4 s.25
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• pp.214-214
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• 1975

This study was conducted to evaluated the nature of the variety Tongil(Suweon 213-1) in resistance to the striped rice borer, Chilo suppressalis Walker, comparing with those of Rexoro(susceptible check) and TKM-6(resistant check) selected at IRRI. 1. The striped rice borer moths much more preferred the variety Tongil for oviposition than the varieties Rexoro and TKM-6. The variety Tongil and more egg masses and number of eggs than the varieties Rexoro and TKM-6, while TKM-6 having more egg masses and more number of eggs than Rexoro. This reaction was consistent throughout the test regardless of the number of tillers per hill. 2. In laboratory, preference of larvae for feeding was studied with 5cm of stem pieces of the varieties. The results showed, in contrast to the case of ovipositional preference, that the striped rice borer larvae least preferred the stems of Tongil among the test varieties, while larvae much more preferred the stems of Rexoro than those of TKM-6. 3. The larval weights at 20 days later infested on the 40 day-old plants were the lowest on Tongil among the test varieties. On the variety Rexoro the larvae had heavier body weights(43.0mg), higher pupation(64.9%) and higher adult emergence(83.3%) than those on Tongil(larval weights 30.3mg, pupation 60%, adult emergence 60.7%) and TKM-6(larval weights 35.7mg, pupation 56.3%, adult emergence 51.9%). The pupal weights, however, were not consistent among the test varieties and/or sexes in comparison with the larval weights, pupation and adult emergence above mentioned. 4. Field experiments indicated that the incidence of dead hearts at 70 days after transplanting was relatively higher on the variety Tongil(11.1%) than those on Rexoro(8.9%) and TKM-6(8.4%), and the incidence of white heads at harvest was, in contrast to the dead hearts, lower on Tongil(9.8%) than those on Rexoro(27.4%) and TKM-6(13.9%). At harvest lower larval survival observed on Tongil (49 larvae/40 hills) than those on the susceptible variety Rexoro(104 larvae/40 hills) and on the resistant variety TKM-6(70 larvae/40 hills). The average larval weights collected from three test varieties at harvest were 80.5mg from Tongil, 83.7mg from TKM-6 and 99.6mg from Rexoro. 5. Increased nitrogen fertilizer application to the variety Tongil, the striped rice borer damage was increased. Also, preference of larvae for feeding significantly increased with the increase of nitrogen fertilizer application. 6. Any specific association between the plant characters and striped rice borer resistance could not be found. The variety Tongil even having large number of tillers, short plant height, large stem, broad leaf, etc, had still high preference of moths for oviposition, low preference of larvae for feeding, low damage, and relatively high antibiosis. 7. Resistance of the variety Tongil to the striped rice borers seemed to be associated with the low feeding preference and the relatively high antibiosis, not associated directly with the ovipositional preference.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.6
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• pp.513-523
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• 1993

Varietal difference in structural and physical characteristics of rice starch and interrelationships between these starch properties and the physicochemical components of rice grains were investigated for twenty four rice varieties, which were considerably different in amylose content, gelatinization temperature and gel consistency, to obtain the basic informations for diversifying the utility of rice grains and for developing various rice cultivars adaptable to rice food processing. Wave length of maximum absorbance for blue color reaction of starch-I$_2$ complex was 520nm for glutinous rice and 560～600nm for nonglutinous rice. The higher amylose rice showed the longer wave length but there was considerable difference of the wave length among rice materials with similar amylose content. Varietal difference in frequency distribution of debranched starch molecules by isoamylase hydrolysis was largest in amylose fraction, the longest fraction(Fr. I), and was next bigger in intermediate fraction(Int.Fr.) and the ratio between short and long glucose chain of amylopectin fraction(Fr. III /Fr. II). The Fr. III / Fr II ratio was higher in glutinous rice than in nonglutinous one but it was considerably different among nonglutinous rice varieties without any connection with amylose content. The lower alkali digestible rice showed the longer half-hydrolysis time in acid solution. Both soft and hard gel rice varieties in gel consistency test revealed significant varietal difference of 50% acid hydrolysis time. The harder rice in gel consistency exhibited the less frequency of short branch fraction of amylopectin (Fr. III) and the higher amylose content. Twenty four rice varieties were cleary classified by upper two principal components contracted from structural or physical traits of rice starch and some physicochemical properties of rice grain by principal component analysis. The 1st and 2nd principal components can be characterized to components related with amylose and amylopectin structure respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.4
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• pp.329-335
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• 1995

Seven varieties of rice were cultivated in the field of BLRI of which three were native (Maloti, Nizershail and Chandrashail) and four were improved ($BR_3$, $BR_{11}$, Pasam and Mala). Yields of straw and grain were recorded and the chemical composition of straw was determined. Both the grain (p < 0.05) and straw (p > 0.05) yields were higher in the improved than the native varities. Relationships of straw dry matter yield with the hights of rice plants, tiller numbers, levels of N fertilizer and lengths of stover were found to be statistically insignificant. No significant differences were observed among the varieties in respect of NDF, cell soluble, cellulose and hemicellulose contents. However, modified acid detergent fibre and insoluble ash content were significantly (p < 0.05) higher in the local varieties. Except $BR_3$, the estimated ME content of straw was higher in the improved than the native varieties. In respect of yield, chemical composition and energy content improved straws were better and Pasam was the best.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.1
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• pp.25-30
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• 1980

Lowland and upland rice were grown concurrently under the both lowland and upland conditions. Yield and its components such as one liter weight, 1, 000 grain weight, number of grain per panicle and number of panicle per hill were compared between varieties and between cultural conditions. Variations of rice quality were also observed about amylose content, alkali digestion value and protein content between varieties and cultural conditions. Most of lowland varieties showed high growing vigour and yielding ability in lowland culture, and they also showed high variations between the lowland and upland cultures compared to upland variety. Upland varieties were revealed higher adaptability in productivity to the lowland condition than upland condition.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.6
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• pp.554-564
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• 2006

It is important to understand pedigree of rice cultivars commonly used for breeding. In this paper, pedigree tables for tracking the pedigree of 17 representative rice cultivars recommended by Rural development Adminstration (RDA) were completed and analyzed using two kinds of web database system; 'IRIS' and 'RRDB'. Seven cultivars, namely, 'Sangmibyeo', 'Ilpumbyeo', 'Saegewhabyeo', 'Surabyeo', 'Shindongjinbyeo', 'Ilmibyeo' and 'Jungwhabyeo' had 'Koshihikari' on the pedigree of their ancestor. Besides 'Koshihikari', the most feguently used ancestral germplasms among the high quality rice cultivars were 'Fujisaka 5', 'Kameno o' and 'Asahi', 'Fujisaka 5' was used as ancestral parent in 12 out of 17 cultivars. Interestingly, 'Kameno o' was used in pedigree of 16 out of 17 high quality varieties and 'Asahi' was used in the ancestral pedigree of all 17 varieties. 'Hwayeongbyeo' was used as one of parent in the breeding of 'Dongjin 1', 'Hwabongbyeo', 'Saegewhabyeo' and 'Junambyeo'. 'Ilpumbyeo' was used in the breeding pathway of 'Junambyeo' and 'Saegewhabyeo', 'Mangeumbyeo' itself was not enlisted as one of high quality rice cultivars, but was used as a breeding parent of three high quality varieties, namely, 'Saegewhabyeo', 'Hwabongbyeo' and 'Nampyeongbyeo'. Incorporated with evaluation data, pedigree will provide a valuable chance to genealogical tracking of agronomic traits such as disease resistance, grain quality and etc.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.820-825
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• 1989

Yukwa (one of most popular Korean traditional popped rice snacks) was made by four different varieties of rice, Shinsun (Japonica) and Hangang $(Japonica{\times}Indica)$ which are waxy rice and Dongjin (Japonica) and Samgang $(Japonica{\times}Indica)$ which are non waxy rice, for their quality by total expansion volume, hardness and brittleness. It was notified that hydration rate of waxy and non waxy rice for preparation of Yukwa were different by 30% and 42% in moisture content respectively soaked at $12^{\circ}C$ for 12 hours and the gelatinization temperature of their starch was $64.5-67.5^{\circ}C$ with no big difference by varieties. The quality of Yukwa was deeply related with amylose contents ranging from 18.5% of non waxy rice to 2-3% of waxy rice. Superior quality (p<0.05) was got from waxy rice. Lactic acid bacterial fermentation didn't improve the quality, and soybean and rice bran oil can be used for popping in even value.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.354-354
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• 2017

Rice grain yield is determined by crop dry matter production that is sensitive to temperature. Our objective was to determine whether the difference in temperature between years had an impact on the relationship between yield components and grain yield. Field experiments were conducted under machine transplanting cultivation by using yield data of two japonica rice varieties, Odaebyeo (early maturing) and Nampyeong (mid-late maturing), in 2013 to 2016 in Suwon, Korea. Plant height, dry weight, and yield components were examined by analysis of variance, correlation. The milled rice yield of the two varieties were the highest in 2016, however the lowest yields were observed in the different years. In 2016, Odaebyeo produced $0.96t\;ha^{-1}$ greater milled rice yield than in 2015, and Nampyeong produced $1.11t\;ha^{-1}$ greater yield than in 2013. The correlation analysis indicated that spikelet per panicle (R = 0.53) was associated with grain yield of Odaebyeo. In Nampyeong, biomass at heading date (R = 0.74), 1000-grain weight (R = 0.71), spikelet per panicle (R = 0.58), and panicle number per $m^2$ were associated with grain yield. Sink size (spikelet number per $m^2$) of the two varieties responded to accumulative temperature from transplanting to panicle initiation stage. In this experiment, optimal accumulative temperature before panicle initiation has effect on increased spikelet number and/or number of panicle that were mainly responsible for yield difference. Rice production research to increase grain yield should consider all yield components, but increased emphasis on biomass production before heading is also necessary as well as grain ripening conditions.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.1
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• pp.20-25
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• 2000

Viviparous germination causes yield loss and quality deterioration of rice. This study was conducted to investigate varietal differences of the viviparous germination with different days after heading (DAH) and different temperatures. In the laboratory examination, the averaged germination rate of all varieties at 45DAH and at 25DAH was 79.9%, and 27.5% under the incubation at the temperature of 3$0^{\circ}C$/2$0^{\circ}C$ (day/night) for 12 days. Andabyeo, Da- sanbyeo, and Nonganbyeo showed the lowest viviparous germination rates among the tested varieties. The shoot length of the viviparous germination measured 12days after incubation at 30/2$0^{\circ}C$ ranged from 21 to 53mm, indicating significant deterioration of rice quality. In the field test, the averaged viviparous germination rates of rice varieties at 25, 35, 45DAH with the underwater conditions for 4 days were 2.2, 6.2 and 9.2%, respectively, while their rates at 12 day after underwater conditions increased to 17.6, 44.2 and 43.8%, respectively. A variety that showed the highest viviparous germination rate at 25 and 35 and 45DAH was Heukjinjubyeo. When standing rice panicles without lodging were examined after consecutive raining for 7 days Juanbyeo showed the highest viviparous germination (45.5%), followed by Odaebyeo (16.0%), Jinbubyeo (14.5 %), Bongkwangbyeo (14.2 %) and Obongbyeo (12.6%). The viviparous germination of rice was greatly affected by variety, days after heading and temperature settings. Bongkwangbyeo, Juanbyeo, Dongjinbyeo, Hwasunchalbyeo, Naepoongbyeo and Heukjinjubyeo were classified as the most susceptible varieties to the viviparous germination in the field conditions.