• Plant Resources
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• 제5권2호
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• pp.155-160
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• 2002

The heading date is known to be controlled by two kinds of genetic constituent, photosensitivity and basic vegetable phase. For the latter, the effect of temperature in early growth period is critical to determine the shortness of vegetative growth periods in plant's life. A phytotron experiment on 55 rice cultivars, consisting of two ecotypes of rices, indica and japonica, was conducted at high and low temperature treatments at early growth stage to investigate the possible role of plant growth stimulus by high temperature to associate with shortening of heading date. The high temperature during the early growth stage stimulated the rice growth as measured by plant height with much difference of the growth response between indica and japonica. The conclusive finding that these growth stimulus in early growth stage was highly correlated with the acceleration of heading is, more or less, correlated with the heading of the late growth stage although we could not conclude the genes for early plant growth stimulus by high temperature is the same genes as the genes for accelerating of heading in the late growth stage of plants.

• 한국식품과학회지
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• 제18권1호
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• pp.38-41
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• 1986

쌀을 실온에서 30분간 침지하고 가수량을 달리하여 취반하고 쌀밥의 관능적성질을 맛, 냄새, 겉모양 및 택스쳐로 나누어 각각 성질 묘사를 3가지씩 하였을 때, 찹쌀밥이 전반적인 관능적 성질에서 가장 높은 강도를 보였다. 멥쌀밥에서는 일반계 품종인 아끼바레쌀밥이 택스쳐 및 외관에서 다수계 품종(밀양23호 및 밀양30호)의 쌀밥보다 높은 강도를 보였다. 취반시 물의 첨가비욜의 증가는 전반적인 관능적 성질에 현저한 영향을 주었으며, 밀양30호 쌀밥의 경우가 가수량에 따라 관능적 성질의 변화가 가장 심하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권21호
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• pp.9517-9522
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• 2014

Purple rice (Oryza sativa L. var. indica) cv. Kum Doisaket is cultivated in northern Thailand. This study evaluated the mutagenic and antimutagenic properties of hydrophilic and lipophilic components of purple rice using the Ames test. The seed and hull of purple rice were extracted with hexane, methanol, ethanol, and water. The methanol extracts had the highest amounts of phenolic acids and flavonoids, while the hexane extracts contained large amount of tocols and ${\gamma}$-oryzanol. None of the extracts were mutagenic in Salmonella typhimurium strains TA98 and TA100. The hexane extract of rice hull and the methanol extract of rice seed were strongly effective against aflatoxin B1- and 2-amino-3, 4 dimethylimidazo (4, 5-f) quinoline-induced mutagenesis, while aqueous extracts showed weakly antimutagenic properties. All extracts with the exception of aqueous extracts enhanced the number of revertant colonies from benzo (a) pyrene induced-mutagenesis. None of the extracts inhibited mutagenesis induced by the direct mutagens 2-(2-furyl)-3-(5-nitro-2-furyl)-acrylamide and sodium azide. The hull extracts showed more potent antimutagenicity than the seed extracts. Based on a chemical analysis, ${\gamma}$-oryzanol and ${\gamma}$-tocotrienol in the hull and cyanidin-3-glucoside and peonidin-3-glucoside in the seed are candidate antimutagens in purple rice. The antimutagenic mechanisms of purple rice might be related to either modulation of mutagen metabolizing enzymes or direct attack on electrophiles. These findings supported the use of Thai purple rice as a cancer chemopreventive agent.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.342-342
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• 2017

Rice seeds are a home to endophytic bacterial communities which serve as a source of the plant's endophytes. As rice undergo physiological and adaptive modifications through cross breeding in the process of attaining salinity tolerance, this may also lead to changes in the endophytic bacterial community especially those residing in the seeds. This study explores the community structure of seed bacterial endophytes as influenced by rice parental lineage, genotype and physiological adaptation to salinity stress. Endophytic bacterial diversity was studied through culture dependent technique, cloning and Terminal-Restriction Fragment Length Polymorphism (T-RFLP) analysis. Results revealed considerably diverse communities of bacterial endophytes in the interior of rice seeds. The richness of ribotypes ranges from 5-14 T-RFs corresponding to major groups of bacterial endophytes in the seeds. Endophytic bacterial diversity of the salt-sensitive IR29 is significantly more diverse compared to those of salt-tolerant cultivars. Proteobacteria followed by Actinobacteria and Firmicutes dominated the overall endophytic bacterial communities of the indica rice seeds based on 16S rDNA analysis of clones and isolates. Community profiles show common ribotypes found in all cultivars of the indica subspecies representing potential core microbiota belonging to Curtobacterium, Flavobacterium, Enterobacter, Xanthomonas, Herbaspirillum, Microbacterium and Stenotrophomonas. Multivariate analysis showed that the bacterial endophytic community and diversity of rice seeds are mainly influenced by their host's genotype, physiological adaptation to salt stress and parental lineage.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.31-31
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• 2017

Understanding the mechanism(s) to overcome or prevent seed ageing deterioration during storage is of fundamental interest to seed physiologists. Vitamin E (tocols) is known as a key metabolite to efficiently scavenge lipid peroxy radicals which cause membrane breakdown resulting in seed ageing. However, in rice research this hypothesis has been tested for very few lines only without considering intraspecific variation in genomic structure. Here, we present a correlation study between tocols and seed longevity using a diverse rice panel. Seeds of 20 rice accessions held in the International Rice Genebank at the International Rice Research Institute, representing aus, indica, temperate japonica and tropical japonica subpopulations, were used for tocols analysis (quantification of ${\alpha}$-, ${\beta}$-, ${\gamma}$-, ${\delta}$-tocopherol/tocotrienol by ultra performance liquid chromatography) and storage experiments at $45^{\circ}C$ and 10.9% seed moisture content (sample taken for germination testing every 3 days up to 60 days). To examine interactions between DNA sequences and phenotype, the 700k high-density single-nucleotide polymorphism marker data-set was utilized. Both seed longevity (time for viability to fall to 50%; $p_{50}$) and tocols content varied across subpopulations due to heterogeneity in the genetic architecture. Among eight types of tocol homologues, ${\alpha}$-tocopherol and ${\gamma}$-tocotrienol were significantly correlated with $p_{50}$ (negatively and positively, respectively). While temperate japonica varieties were most abundant in ${\alpha}$-tocopherol, indica varieties recorded 1.3 to 1.7-fold higher ${\gamma}$-tocotrienol than those of other subpopulations. It was highlighted that specific ratio of tocol homologues rather than total tocols content plays an important role in the seed longevity mechanism.

• 한국작물학회지
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• 제41권4호
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• pp.434-440
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• 1996

수발아가 벼의 품질 및 정현 비율 감소에 미치는 영향, 수발아성의 품종간 차이 및 왕겨로부터 발아 억제물질을 추출하여 수발아 방제를 위한 기초자료를 얻고자 실시한 결과는 다음과 같다. 1. 현미중은 무처리에 비하여 수발아 처리일수가 길어질수록 감소되는 경향으로 6일 처리시 약 20% 감소되었다. 2. 수발아 처리일수에 따른 완전립 비율은 무처리가 99.5%인데 반해 6일 처리시 41.3%로 현저히 저하되었다. 3. 인디카품종은 대부분 난수발아성이었으나 자포니카(9.2∼79.7%) 및 통일형 품종(2.1∼63.7%)은 품종간 차이가 현저히 나타났다. 4. 난수발아성인 IR36, 신운봉벼 및 중원벼의 왕겨를 메탄올을 이용하여 추출한 물질이 발아억제에 효과가 있었다.

• Journal of Crop Science and Biotechnology
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• 제10권4호
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• pp.265-276
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• 2007

The 13 major blast resistance(R) genes against Magnaporthe grisea were screened in a number of Korean rice varieties using molecular markers. Of the 98 rice varieties tested, 28 were found to contain the Pia gene originating from Japanese japonica rice genotypes. The Pib gene from BL1 and BL7 was incorporated into 39 Korean japonica varieties, whereas this same gene from the IRRI-bred indica varieties was detected in all Tongil-type varieties. We also found that 17 of the japonica varieties contained the Pii gene. The Pii gene in Korean rice varieties originates from the Korean japonica variety Nongbaeg, and Japanese japonica varieties Hitomebore, Inabawase, and Todorokiwase. The Pi5 gene, which clusters with Pii on chromosome 9, was identified only in Taebaeg. Thirty-four varieties were found to contain alleles of the resistance gene Pita or Pita-2. The Pita gene in japonica varieties was found to be inherited from the Japanese japonica genotype Shimokita, and the Pita-2 gene was from Fuji280 and Sadominori. Seventeen japonica and one Tongil-type varieties contained the Piz gene, which in the japonica varieties originates from Fukuhikari and 54BC-68. The Piz-t gene contained in three Tongil-type varieties was derived from IRRI-bred indica rice varieties. The Pi9(t) gene locus that is present in Korean japonica and Tongil-type varieties was not inherited from the original Pi9 gene from wild rice Oryza minuta. The Pik-multiple allele genes Pik, Pik-m, and Pik-p were identified in 24 of the varieties tested. In addition, the Pit gene inherited from the indica rice K59 strain was not found in any of the Korean japonica or Tongil-type varieties tested.

• Weed & Turfgrass Science
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• 제5권4호
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• pp.187-190
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• 2016

4-HPPD저해 제초제에 의한 주요 벼품종의 약해반응과 약제반응에 관여하는 유전자(HIS1) 특성을 구명하기 위해 본시험을 수행하였다. Benzobicyclon 액상수화제 처리에 Japonica 품종인 상주벼에는 백화증상의 약해증상이 발생하지 않았으며, Japonica 품종임에도 불구하고 삼백벼에서는 기준량에서는 2-3, 배량에서는 3-4의 백화증상의 약해가 발생하였으며, 산들진미, 금영 품종에서는 3-4 및 4-5의 약해증상을 보였다. 또한 Indica 품종인 IR-8 품종에서는 기준량에서 3~5, 배량에서는 4~6의 가증 심한 약해증상을 보였다. 4-HPPD저해 제초제애 대해서 약제반응에 관여하는 HIS1 유전자 보유여부를 확인하기 위해 일반계 품종인 상주벼와, 삼백벼, 산들진미, 금영과 통일형 품종인 IR-8품종으로부터 저항성 표적유전자와 동일 HIS1 유전자를 분리하였다. 각 품종별 HIS1유전자를 PCR등을 통해 염기서열을 확인한 결과 HIS1 유전자는 생태형에 상관없이 시험한 5품종 모두에서 HIS1유전자를 보유하고 있는 것으로 확인되어, 본 유전자로 HPPD 약해 발생 유무를 검증할 수 없음이 확인되었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 1986년도 춘계 학술대회지
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• pp.24-25
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• 1986

• 한국작물학회:학술대회논문집
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• 한국작물학회 1986년도 춘계 학술대회지
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• pp.22-23
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• 1986