• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.304-304
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• 2017

In semi-arid countries such as Namibia, the flooding unexpectedly happens in a rainy season, causing losses in the yield of upland-adapted cereal crop. In flooding conditions, rice roots sequentially form aerenchyma and a barrier to radial oxygen loss (ROL), and oxygen is released into the rhizosphere near the root tips. Iijima et al. (2016) and Awala et al. (2016) reported that close mixed-planting with rice can mitigate the flood stress of co-growing upland-adapted cereal crop by modifying their rhizosphere microenvironments via the oxygen released from the rice roots. Moreover, by using the model system of hydroponic culture, it was confirmed that oxygen from rice roots was transferred to co-growing upland-adapted cereal crop in close mixed planting system (Kawato et al., 2016). However, it is not sure whether the ability of oxygen release varies among rice cultivars, because Kawato et al. (2016) used only one japonica cultivar, Nipponbare (Oryza sativa). The objective of this study was to compare the ability of oxygen release in rhizosphere among rice cultivars. The experiment was conducted in a climate chamber in Kindai University. We used 10 rice cultivars from three different rice species (O. sativa (var. japonica (2), var. indica (3)), Oryza glaberrima Steud. (2) and their interspecific progenies (3)) to compare the ability of oxygen release from the roots. According to the method by Kawato et al. (2016), the dissolved oxygen concentration of phase I (with shoot) and phase II (without shoot) were measured by a fiber optic oxygen-sensing probe. The oxygen released from rice roots was calculated from the difference of the measurements between phase I and phase II. The result in this study indicated that all of the rice cultivars released oxygen from their roots, and the amount of released oxygen was significantly correlated with the above-ground biomass (r = 0.710). The ability of oxygen release (the amount of the oxygen release per fresh root weight) of indica cultivars (O. sativa) tended to be higher as compared with the other cultivars. On the other hand, that of African rice (O. glaberrima) and the interspecific progenies tended to be lower. These results suggested that the ability of oxygen release widely varies among rice cultivars, and some of indica cultivars (O. sativa) may be suitable for close mixed-planting to mitigate flood stress of upland-adapted cereal crop.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2005년도 추계학술발표회 요지
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• pp.330-331
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• 2005

• The Plant Pathology Journal
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• 제37권4호
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• pp.375-388
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• 2021

Rice yellow mottle virus (RYMV) is the most harmful virus that affects irrigated and lowland rice in Africa. The RBe24 isolate of the virus is the most pathogenic strain in Benin. A total of 79 genotypes including susceptible IR64 (Oryza sativa) and the resistant TOG5681 (O. glaberrima) as checks were screened for their reactions to RBe24 isolate of RYMV and the effects of silicon on the response of host plants to the virus investigated. The experiment was a three-factor factorial consisting of genotypes, inoculation level (inoculated vs. non-inoculated), and silicon dose (0, 5, and 10 g/plant) applied as CaSiO₃ with two replications and carried out twice in the screen house. Significant differences were observed among the rice genotypes. Fifteen highly resistant and eight resistant genotypes were identified, and these were mainly O. glaberrima. Silicon application did not affect disease incidence and severity at 21 and 42 days after inoculation (DAI); it, however, significantly increased plant height of inoculated (3.6% for 5 g CaSiO₃/plant and 6.3% for 10 g CaSiO₃/plant) and non-inoculated (1.9% for 5 g CaSiO₃/plant and 4.9% for 10 g CaSiO₃/plant) plants at 42 DAI, with a reduction in the number of tillers (12.3% for both 5 and 10 g CaSiO₃/plant) and leaves (26.8% for 5 g CaSiO₃/plant and 28% for 10 g CaSiO₃/plant) under both inoculation treatments. Our results confirm O. glaberrima germplasm as an important source of resistance to RYMV, and critical in developing a comprehensive strategy for the control of RYMV in West Africa.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.94-94
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• 2017

Oryza sativa and Oryza glaberrima are rice cultivars distributed in Asia and Africa. There are several differences between these cultivars in morphological characteristics such as panicle structure and especially the secondary branch number of O. glaberrima is less than that of O. sativa. Generally, branch number of panicle related to a large vascular bundle number (VBN) among O. sativa and there is a wide variation of the VBN of the peduncle from where the bundles enter into the rachis branches. However, there is less information about VBN in O. glaberrima and also the relationship between VBN and branch numbers, the primary branch number (PBN) and secondary branch number (SBN). Additionally, the genetic factor for VBN and branch number in O. glaberrima is not completely exploited. In this study, phenotypic variation for VBN and panicle structure were investigated using a set of 40 $BC_3$ -derived from IRGC 104038 (O. glaberrima from Senegal) and 35 $BC_4$ -derived from IRGC103777 (O. glaberrima from Mali) introgression lines with a genetic background of japonica rice Taichung 65. Taichung 65 had 11.8 PBN, 16.0 SBN and 11.5 VBN, while IRGC 103777 had 12.0 PBN, 15.0 SBN and 15.3 VBN. The introgression lines derived from IRGC 104038 had range from 9.0 to 14.4 in the PBN, range from 9.6 to 33.5 in the SBN and range from 9.8 to 14.8 in the VBN. Additionally, the introgression lines derived from IRGC 103777 had range from 9.0 to 18.5 in the PBN, range from 10.3 to 39.0 in the SBN and range from 9.0 to 15.3 in the VBN. Among two set of introgression lines, there are significant correlation between VBN and PBN. Multiple introgression lines indicated higher PBN, SBN and VBN than Taichung 65 and these examined characteristics are supposedly controlled by quantitative traits loci. The genetic factor related to VBN and panicle architecture can be revealed using segregating population in future study.

• 한국식품영양과학회지
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• 제45권5호
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• pp.696-701
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• 2016

본 연구에서는 열처리 및 발아와 발아 벼로부터 추출한 조효소액에 의한 왕겨의 tricin과 4'-O-(threo-${\beta}$-guaiacylglyceryl) ether(TTGE)의 함량 변화에 대해 살펴보았다. 열처리에 의한 왕겨의 tricin과 TTGE의 함량은 온도 및 시간이 증가함에 따라 증가하였고 $130^{\circ}C$에서 1시간 처리하였을 때 각각 253.12 및 $208.39{\mu}g/g$으로 가장 높게 나타났으며, 발아 2일차에서 각각 118.20 및 $95.37{\mu}g/g$으로 가장 높게 나타났다. 발아일수별 벼의 조효소액을 여과한 조효소액 및 여과 후 남은 잔여물을 접종한 결과 여과한 조효소액의 처리구에서는 뚜렷한 함량 차이가 없었으나 잔여물을 처리하였을 때 tricin 및 TTGE의 함량이 유의적으로 증가하였다. 특히 발아 벼 6일 차에서 각각 361.76 및 $308.08{\mu}g/g$으로 가장 많은 함량을 나타내었다. 이상의 결과로부터 tricin과 TTGE의 함량을 가장 많이 증대시킬 수 있는 조건은 발아 6일차 벼로부터 추출한 조효소액 여과 잔여물을 처리한 경우로 나타났다.

• 한국식품영양학회지
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• 제36권6호
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• pp.506-514
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• 2023

Reported positive ion fragmentation of phenolic acid derivatives in rice (Oryza sativa L.) were summarized based on the literature. A total of eight phenolic acids (4 derivatives of ferulic acid, 3 derivatives of sinapic acid and p-coumaric acid) were isolated and identified from rice (raw and steamed) using UPLC-DAD-QToF/MS. Results revealed that 6-O-feruloylsurose was the major component with 3'-O-sinapoylsucorse being tentatively identified in Oryza sativa L. for the first time as a new hydroxycinnamoyl derivative in rice grains. In our study, raw brown rice had the highest phenolic acid contents with Samkwang showing higher phenolic acid content than Saeilmi and Sindongjin (12.41 vs. 7.89 and 3.10 mg/100 g dry weight, respectively). Of all varieties, brown rice had higher phenolic acid contents than white rice. These contents decreased considerably when rice was steamed whereas, p-coumaric acid and ferulic acid contents were increased. Additionally, contents of rice (raw and steamed) can be used as a fundamental report for new rice varieties.

• 한국광과학회:학술대회논문집
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• 한국광과학회 2006년도 정기총회 및 제13회 학술대회 논문 초록
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• pp.23-23
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• 2006

• 한국육종학회지
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• 제41권2호
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• pp.101-105
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• 2009

전 세계에서 광범위하게 수집한 벼 유전자원 320개를 63개의 아종특이적마커로 분석하여 유전자원의 다양성, 유연관계 및 유전집단의 구조분석을 하여 아종특이적마커의 아종판별 효율을 검정하고 아종의 게놈 구성을 검토하고자 본 시험을 수행하였다. 1. 본 연구에서 사용한 63개의 아종특이적 마커는 벼 품종을 인디카와 자포니카 두 아종으로 구분하는데 효과적으로 이용할 수 있었다. 2. 실험에 사용한 320개의 벼 유전자원들은 자포니카군(128개)과 인디카군(178개)으로 나눌 수 있었고 Basmati370, Shennong27 등 14개 품종은 중간형 admixture형태의 품종으로 구분할 수 있었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2000년도 추계 학술대회지
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• pp.83-85
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• 2000

• 생명과학회지
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• 제20권8호
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• pp.1173-1180
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• 2010

Salt stress가 벼 잎 내 광합성 효율과 ascorbate peroxidase (APX) 활성에 미치는 영향을 조사하였다. 염 농도가 증가(NaCl, 100-300 mM) 할수록 Fv/Fm 값이 감소한 반면, $H_2O_2$ 양과 APX 활성은 증가하였다. APX isoforms 중 APX 1 (stromal)은 300 mM NaCl 처리 시 활성이 거의 나타나지 않는 반면, chilling이나 drought 처리 시에는 변화가 없었다. 또한 gel 상에서의 서로 다른 APX isoforms의 활성이 유전자 발현에서도 확인이 되는지를 알아보기 위해 RT-PCR을 수행하였다. 구획별 APX isoforms의 RT-PCR 수행 결과, cytosolic/thylakoid bound APX 발현양은 증가한 반면, stromal APX 발현은 매우 감소하였다. 이러한 실험 결과는 salt에 의해 구획별로 APX 활성이 영향을 받음을 나타낸다.