• 한국식품과학회지
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• 제24권2호
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• pp.187-192
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• 1992

일반계와 통일계 쌀 전분에 대한 구조적 성질을 조사하고 그 차이점을 비교하였다. 쌀 성분의 호화온도 범위는 일반계가 통일계보다 넓었고 쌀 전분의 최대 흡수파장은 일반계가 통일계 보다 높았다. 고유점도는 전분, 아밀로오스와 아밀로펙틴 모두 일반계가 통일계 보다 낮았다. ${\beta}$-아밀라아제 분해 한도는 전분에서는 차이가 없으나 아밀로오스와 아밀로펙틴은 일반계가 통일계 보다 약간 낮았다. 아밀로펙틴의 평균 사슬 길이와 바깥 사슬 길이는 일반계가 통일계 보다 짧았으나 안쪽 사슬 길이는 차이가 없었다. 열수 가용성 전분과 아밀로오스 함량은 일반계가 통일계 보다 높았다. 또한 열수 가용성 전분을 겔 크로마토그래피한 결과는 품종마다 독특한 용출모양을 보였다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.301-301
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• 2017

Subspecific difference of the percentage of white immature kernels (WIK) between japonica and indica rice cultivars was analyzed in relation to ripening temperature and yield characters. Thirty-three Chinese and 10 Japanese rice cultivars, including 32 japonica and 11 indica, were cultivated with three different cropping seasons for three years. The results were as follows: (1) Indica had less number of panicles, larger number of spikelets per panicle with higher yield, and longer and narrower kernels than japonica. In japonica, Chinese cultivars had less number of panicles and larger number of spikelets per panicle than Japanese cultivars. In addition, WIK was significantly higher in Chinese cultivars than in Japanese cultivars, because of the higher percentage of milky white kernels, even at similar temperature conditions during ripening. On the other hand, WIK in indica was not significantly different between the production areas and between the cropping seasons. (2) Regardless of subspecies, WIK in a large number of Chinese cultivars increased with increasing temperature during ripening within 20 days after heading, while this relation was uncommon in Japanese cultivars, showing the low temperature response. However, some Chinese cultivars had the low WIK with the low temperature response. (3) WIK in japonicawas positively correlated with 1000-kernel weight, spikelet density, kernel width and thickness, but negatively correlated with panicle length and grain filling percentage, while in indica it was positively correlated with panicle number per area, grain filling percentage, brown rice yield and kernel width, but negatively correlated with kernel length. These results indicated that WIK in both subspecies had a close relation to kernel size, and that WIK was high in japonica cultivars with wide and thick kernels and in indica cultivars with short and wide kernels.

• 한국식품영양학회:학술대회논문집
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• 한국식품영양학회 2001년도 동계 학술심포지움
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• pp.39-74
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• 2001

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 qualify 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 caltivars 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. 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 torture of cooked rice. The glossiness or gross palatability score of cooked rice were closely associated with the peak. hot paste and consistency viscosities of viscogram with year difference. The high-quality rice variety “Ilpumbyeo” 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 mcroscope. 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 Ilpumbyeo, Chucheongbyeo, Sasanishiki, Jinbubyeo and Koshihikari. A Tongil-type rice, Taebaegbyeo, and a japonica cultivar, Seomjinbyeo, shelved the relatively fast deterioration of cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogiadation 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 bread. 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 gram rices showed better suitability for fermentation and brewing. Our breeding efforts on rice quality improvement for the future should focus on enhancement of palatability of cooked rice and marketing qualify as well as the diversification in morphological and physicochemical characteristics of rice grain for various value-added rice food processings.

• 한국작물학회지
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• 제44권2호
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• pp.112-116
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• 1999

Genetic diversity of 31 rice varieties including 25 japonica and 6 indica varieties was evaluated using a combination of 19 microsatellite or simple sequence repeats (SSRs) and 28 random decamer oligonucle-otide primers. All 19 microsatellite primer sets representing 19 loci in the rice genome showed polymorphisms among the 31 varieties and revealed 91 alleles with an average of 4.80 bands per primer. Also all 28 random decamer primers used were informative and generated 114 non-redundant bands with a mean of 4.07 bands. Microsatellite markers detected higher number of alleles than random primers .although the mean difference was not statistically significant. A cluster analysis based on Nei＇s genetic distances calculated from the 205 bands resolved the 31 varieties into two major groups that correspond to indica and japonica subspecies, which is consistent with the genealogical information. As few as six random decamer primers or a combination of one microsatellite and four random decamer primers were sufficient to uniquely differentiate all 31 varieties. These combinations would be potentially useful in rice variety protection and identification considering that 25 out of 31 varieties used in this study are japonica rices with high grain quality and have close make up.

• 한국작물학회지
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• 제42권3호
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• pp.338-343
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• 1997

벼 품종의 오존 저항성 판단을 위한 시험에서 오존의 처리농도는 0.3 ppm이 0.1 ppm보다 뚜렷한 결과를 보였고, 처리시간은 2∼4시간이 알맞은 것으로 나타났다. 묘대일수에 따른 저항성 정도는 파종후 3주까지는 생육이 진전될수록 높아지는 경향이었으나 3∼5주간에는 큰 차이가 없었다. 인디카와 통일형 품종들이 자포니카 품종보다 저항성이 높은 경향이었고, 자포니카 품종 중에서 장안벼외 7 품종은 높은 저항성을 나타내었다. 벼의 생육시기에 따른 피해엽율은 간척벼는 유묘기에서 밀양 2003외 4 품종은 최고 분열기에서 가장 높게 나타났고 임실율은 수잉기 처리에서 가장 낮았다.

• 한국작물학회지
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• 제65권1호
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• pp.1-21
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• 2020

Association mapping is widely used in rice and other crops to identify genes underlying important agronomic traits. Most association mapping studies use diversity panels comprising accessions with various geographical origins to exploit their wide genetic variation. While locally adapted breeding lines are rarely used in association mapping owing to limited genetic diversity, genes/alleles identified from elite germplasm are practically valuable as they can be directly utilized in breeding programs. In this study, we analyzed genetic diversity of 179 rice varieties (161 japonica and 18 Tongil-type) released in Korea from 1970 to 2006 using 192 microsatellite markers evenly distributed across the genome. The 161 japonica rice varieties were genetically very close to each other with limited diversity as they were developed mainly through elite-by-elite crosses to meet the specific local demands for high quality japonica rice in Korea. Despite the narrow genetic background, abundant phenotypic variation was observed in heading time, culm length, and amylose and protein content in the 161 japonica rice varieties. Using these varieties in association mapping, we identified six, seven, ten, and four loci significantly associated with heading time, culm length, and amylose and protein content, respectively. The sums of allelic effects of these loci showed highly significant positive correlation with the observed phenotypic values for each trait, indicating that the allelic variation at these loci can be useful when designing cross combinations and predicting progeny performance in local breeding programs.

• 한국환경농학회지
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• 제29권1호
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• pp.1-6
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• 2010

Organic farming system in rice paddy is rapidly expanding in Korea. This study was to find out optimum japonica rice cultivars for organic farming. A field research was conducted to evaluate the characteristics of japonica rice cultivars under no-tillage paddy at Doo-ryangmyeon, Sacheon, Gyeongsangnam-do, Korea. The experimental soil was Juggog series (silty clay loam: 56.0% silt, 31.2% clay and 12.8% sand). In experiment, ten lines of Japanese rice cultivars were tested under no-tillage amended with rye (NTR) and no-tillage without cover crop treatment (NTNT). In addition, two Korean japonica rice cultivars as check cultivars were used in this study. The grain yield in NTR was significantly higher in 6.13 Mg $ha^{-1}$ for Kinuhikari, 5.30 Mg $ha^{-1}$ for Komekogane, 5.25 Mg $ha^{-1}$ for Kosihikari, 5.22 Mg $ha^{-1}$ for Mazizbare and 5.12 Mg $ha^{-1}$ for Akitakomachi compared to two Korean rice cultivars (4.57 Mg $ha^{-1}$ for Hwayoungbyeo and 4.00 Mg $ha^{-1}$ for Ilmibyeo) in that order. While, grain yield in NTNT was significantly higher in 4.90 Mg $ha^{-1}$ for Akitakomachi 3.81 Mg $ha^{-1}$ for Hinohikari, 3.74 Mg $ha^{-1}$ for Umezkusi, 3.67 Mg $ha^{-1}$ for Kosihikari and 3.54 Mg $ha^{-1}$ for Dondokuri compared to 3.02 Mg $ha^{-1}$ for Ilmibyeo and 2.36 Mg $ha^{-1}$ for Hwayoungbyeo, respectively. The number of panicle per $m^2$ and grain number per panicle were indispensible for increasing the yield of rice. These results were able to find out optimum japonica rice cultivar Akitakomachi for organic farming in no-tillage paddy.

• 아시안잔디학회지
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• 제4권2호
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• pp.101-118
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• 1990

Effects of Zoysia japonica fired in winter on the arthropoda communities in its grassland and rice field was investigated . The results gave indicated that a significant difference between total 15,120 individuals of 4 classes, 11 orders, 47 families, 92 genera and 103 species in the control of Zoysia japonica grassland, and total 1, 404 individuals of 4 classes, 11 orders, 47 families, 53 genera 65 species in the Zoysia japonica grassland fired in winter. Index of similarity of Zoysia japonica grasslands between Kimpo and Yangsuri areas was 0.51. Dominant species of arthropoda communities in Zysia japonica grasstands in Kimpo and Yangsuri areas were Hypogastnua sp. and Proisotorn sp., respectively. The spiders were 9 families and 27 species at Kimpo, and t2 families. and 44 species at Yangsuri, and their dominant species was Gnathonariurn dentaturn at two areas. Laodelphex striatelus in the Zoysia japonica grassland fired in winter was sampled constantly morning, noon and night, hut Gnatlzonariun dentatum was sampled more frequently in the morning than at night. Damage of the spiders in the Zoysia japonica granssland fired in winter was more severe than that of Laodelphcx striatelus .

• 한국잡초학회지
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• 제32권3호
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• pp.240-255
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• 2012

본 연구의 목적은 설포닐우레아계 제초제에 대한 저항성 잡초종 방제에 효과적인 HPPD(4-hydroxy phenylpyruvate dioxygenase) 저해 제초제, mestrione, benzobicyclone 및 tefuryltrion에 대한 벼 품종 간의 약해정도를 구명하기 위하여 수행하였다. 총 26 벼 품종(통일형 8품종 그리고 일본형 18품종)은 육묘상자에서 25일 동안 생육시킨 후 이앙하였고, 이앙 후 5, 10, 그리고 15일에 각각의 제초제를 표준량 그리고 배량을 처리하였다. 비록 mestrione, benzobicyclone 및 tefuryltrion 제초제가 동일한 HPPD 저해 제초제들이지만 이들 제초제의 처리 시기나 약량에 따라 벼 품종별 약해정도와 증상은 서로 상이하였다. 시험약제 모두에서 통일형 품종이 일본형 품종보다 약해가 심하게 발생하였다. Mesotrione은 약량이 증가할수록, benzobicyclon은 처리시기가 빠르고 약량이 증가할수록 약해가 심하였다. 반면에 tefuryltrion은 처리시기와 약량에 따라 품종간의 약해변이는 크지 않았다. Mesotrione과 benzobicyclon에 대한 통일형 품종인 한강찰벼 1호와 향미벼 1호, 초다수성 품종인 남천벼, 다산벼, 아름벼, 그리고 한아름벼 품종들의 약해는 처리시기 및 약량에 관계없이 백화, 잎과 줄기의 갈변, 잎 꺾임, 괴사를 동반한 5~8 정도의 약해 증상을 보인 반면에 tefuryltrion은 단지 1~3 정도의 황화 및 백화, 갈변 증상만을 보였다. 일본형 품종에 대한 약해는 제초제의 처리시 기와 약량에 따라 1~2 정도의 가벼운 약해 증상을 보였지만 제초제 종류에 따라 품종간에 유의적인 차이를 나타냈다. 13개의 일본형 품종들은 benzobicyclone에 대해 민감하였으며, 일본형 4품종과 7품종들은 각각의 mestrione과 tefuryltrion에 대해 황화 및 백화를 동반한 증상이 나타났다. 그러므로 mestrione과 benzobicyclone, 그리고 tefuryltrion 성분이 함유된 혼합제는 처리시기 및 처리약량에 관계없이 벼 생태형 간에 심각한 약해 증상을 나타내므로 식용(기능성용 및 가공용 벼) 또는 사료용을 위한 벼 재배 포장에서의 사용을 지양해야 할 것으로 사료된다.

• 한국식품과학회지
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• 제20권1호
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• pp.59-62
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• 1988

일반계 및 다수계 쌀 각 6품종을 대상으로 뜨거운 밥($70^{\circ}C$)과 식은 밥($20^{\circ}C$)의 텍스쳐를 평가하고 쌀 및 전분의 성질과의 상호 관계를 조사 하였다. 일반계와 다수계 밥의 텍스쳐는 유의적인 차이를 보이지 않았다. 밥의 단단함은 식은 밥에서 set-back과 정의상관(${\gamma}$=0.613)관계를 나타내었으며, 쌀의 아밀로스 함량은 밥의 단단함과는 뚜렷한 상관 관계를 보이지 않았다.