• Molecules and Cells
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• 제24권3호
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• pp.394-408
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• 2007

Several genes/QTLs governing resistance/tolerance to abiotic and biotic stresses have been reported and mapped in rice. A QTL for submergence tolerance was found to be co-located with a major QTL for broad-spectrum bacterial leaf blight (bs-blb) resistance on the long arm of chromosome 5 in indica cultivars FR13A and IET8585. Using the Nipponbare (japonica) and 93-11 (indica) genome sequences, we identified, in silico, candidate genes in the chromosomal region [Kottapalli et al. (2006)]. Transcriptional profiling of FR13A and IET8585 using a rice 22K oligo array validated the above findings. Based on in silico analysis and arraying we observed that both cultivars respond to the above stresses through a common signaling system involving protein kinases, adenosine mono phosphate kinase, leucine rich repeat, PDZ/DHR/GLGF, and response regulator receiver protein. The combined approaches suggest that transcription factor EREBP on long arm of chromosome 5 regulates both submergence tolerance and blb resistance. Pyruvate decarboxylase and alcohol dehydrogenase, co-located in the same region, are candidate downstream genes for submergence tolerance at the seedling stage, and t-snare for bs-blb resistance. We also detected up-regulation of novel defense/stress-related genes including those encoding fumaryl aceto acetate (FAA) hydrolase, scramblase, and galactose oxidase, in response to the imposed stresses.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.147-147
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• 2017

Rice is one of the major staple food in Asia, covering around half of the world population. More than 40% of rice cultivation area are subject to abiotic stresses such as drought, submergence and phosphate deficiency. Pyramiding useful genes into elite variety is a promising strategy to develop tolerance varieties to multiple abiotic stresses. However, some genes are not functionally compatible when they are introgressed into the same elite variety. Here, we tested the functional compatibility of Sub1 and Pup1, major QTLs for tolerance to submergence and phosphate (P)-deficiency conditions, respectively. Phenotypic analysis revealed that IR64-Sub1 Pup1(SP1) plants harboring both Sub1 and Pup1 QTLs showed significant tolerance to submerged conditions, similarly in IR64-Sub1 (Sub1) plant, while SP1 plants failed to tolerate to P-deficiency conditions; only IR64-Pup1 (Pup1) showed strong P-deficiency tolerance phenotype. In submerged conditions, the expression levels of Sub1A and PSTOL1, major genes for Sub1 and Pup1 QTLs, respectively, were not significantly different in between Pup1 and SP1 plants. On the other hand, the expression of both Sup1A and PSTOL1 was significantly downregulated in P-deficiency conditions, suggesting that Sub1 and Pup1 repressed gene expression each other in P-deficiency conditions. These results suggest Pup1 does not compromise the Sub1 function in submerged conditions while Sub1 suppresses the function of Pup1 in (P)-deficient condition, possibly by regulating transcript level of Pup1. In conclusion, Sub1 and Pup1 are functionally compatible in terms of submergence tolerance but not in P-deficiency conditions. Further analysis need to be performed to elucidate how Sup1 suppresses the function of Pup1 in P-deficiency conditions.

• Journal of Plant Biotechnology
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• 제5권3호
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• pp.173-179
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• 2003

The combination of a radiation technique with an in vitro culture system was appiled to develop submergence tolerant rice. The 3,000 $M_3$ lines with an average 80 percent of fertile grain were utilized for the selection of submergence tolerance. Salt tolerant lines were selected based on high plant height, root length and root number after submergence in plastic pots. Of the lines tested, the tolerant line (403-6) showed a dramatic difference in morphological traits under submergence compared to its original variety (Dongjinbyeo). It was suggested that genetic variations between the original variety and $M_3$-403-6 did exist. The levels of $\alpha$-amylase and alcohol dehydrogenase activities were significantly increased in the mutant line compared to its original variety. The mutant with greater tolerance showed less electrolyte leakage indicating a greater membrane integrity and better survival. Also, this line was much more resistant to a salt stress of $1.25\%$ than the original variety. The proline level of the line was significantly (p<0.01> higher than that of the original variety. The relationships between the inhibition of growth caused by stress and the physiological changes in the plant cell were discussed.

• 한국작물학회지
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• 제49권2호
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• pp.126-130
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• 2004

This study is to identify the physiological traits of submergence-tolerant varieties of rice plants (Oryza sativa L.) in Yeongnam area, southeastern part of Korea, where the reduction of rice yield due to submergence is remarkably severe. In the present study, two tolerant varieties of rice plants were selected from over 30 rice varieties grown in under a 10-day period. The tolerant varieties selected from a submerged paddy field. As a control, one intolerant variety of rice plant was chosen. Of the tolerant variety Samgangbyeo, rather than Haepyungbyeo, had a lower dissolved oxygen consumption and maintained a higher dry weight than the intolerant variety. The leaf photosynthetic rates (LPS) of the two tolerant varieties were significantly higher than that of the intolerant-variety after four days of submergence treatment. These results indicate that lower dissolved oxygen consumption in a limited pool is prevented by ethylene formation in the tolerant varieties, which may be a mechanism of submergence tolerance.

• Journal of Forest and Environmental Science
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• 제23권2호
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• pp.93-100
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• 2007

This study was carried out to select the utilizable vegetations for the stabilization of slopes and river banks, landscape creation and water quality cleansing in dams, lakes and streams. In this study, 4 species were investigated for their survival and growth characteristics in the complete and partly flooding conditions with various flooding periods. The results are as followings; Acorus calamus var. angustatus showed the highest flooding tolerance based on survival rate and growth condition. Equisetum hyemale, Acorus gramineus and Salix gracilistyla followed after Acorus calamus var. angustatus in the order of flooding tolerance. Particularly, A. calamus var. angustatus and E. hyemale showed higher survival rate and grew well even when they were completely submerged in the water up to 120 days. As they were partially submerged longer, they grew better. This ascertained that they had strong flooding tolerance. When A. gramineus were completely submerged in the water, their growth was disturbed but they did not die in the complete submergence up to 120 days. A. gramineus had a small growth disturbance and showed the highest vitality of leaves among the species. Though S. gracilistyla showed somewhat low growth rate in the complete water submergence and died in 90 days, it also can grow back to normal with some changes of water level.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.5-5
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• 2017

Too little and too much water due to climatic events is a significant cause of global food insecurity. Crops are less productive under water-limited conditions and all major crops, with the exception of rice (Oryza sativa), die within a few days of complete submergence. To complement our studies on genes such as SUB1A, (an ERF-VII transcription factor that provides robust submergence tolerance) and AG1 (a TREHALOSE 6-P PHOSPHATASE that promotes establishment of young seedlings underwater), we have retooled INTACT (${\underline{I}}solation$ of ${\underline{N}}uclei$ ${\underline{TA}}gged$ in specific ${\underline{C}}ell$ ${\underline{T}}ypes$) and TRAP (${\underline{T}}ranslating$ ${\underline{R}}ibosome$ ${\underline{A}}ffinity$ ${\underline{P}}urification$) for rice. These technologies enable us to follow dynamics in chromatin, nuclear pre-mRNAs and ribosome-bound mRNAs in meristems and diverse cell types. With these technologies we can better interpret responses to stresses and reestablishment of homeostasis. These include stress acclimation strategies involving changes in metabolism and development, such as dynamics in suberin deposition in sub-epidermal layers of roots that limit water loss under drought and oxygen escape during waterlogging. Our new data uncover dynamic and reversible regulation at multiple levels of gene regulation and provide new insights into processes of stress resilience. Supported by US NSF-PGRP Plasticity (IOS-1238243), Secretome (IOS-1546879) and REU (DBI-146129) grants.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.31-31
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• 2022

Rice contains a wealth of genetic diversity, both within Oryza sativa and in related A-genome species. Decades of genetic research into this diversity have identified dozens of major genes contributing to a wide variety of important traits, including disease resistance, abiotic stress tolerance (drought, salinity, submergence, heat, cold etc.), grain quality, flowering date and maturity and plant architecture. Yet despite these opportunities, very few of the major genes and QTLs known have been successfully applied through rice breeding programs to produce sustained changes in farmer's fields. This presentation will briefly examine some of the factors limiting application of major genes in the mainstream breeding programs, and steps that have been taken to alleviate those limitations. As a result of these interventions, dozens of major genes that were previously unavailable to breeders are now being used confidently in the variety development process. Case studies will be discussed of genes critical for blast resistance worldwide, rice yellow mottle virus for Africa, and new validated QTLs for salinity tolerance.

• 한국작물학회지
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• 제28권1호
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• pp.100-106
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• 1983

이 연구에서는 벼 생육기 침수에서 피해가 가장 뚜렷이 나타나는 주요생육형질의 품종간 차이와 벼의 생식생장기 침수에서 피해를 크게 좌우하는 임실장해의 정도가 가장 예민하게 나타나는 시점을 찾기 위하여 벼의 포기단위, 이삭단위, 그리고 영화단위로 청수와 탁수로 처리하여 얻어진 결과를 요약하면 다음과 같다. 1. 침수일수의 증가에 따라 엽초의 이상신장량이 많아졌고, 침수후의 초장신장량 및 분벽수는 감소되었으며 출수지연일수가 길어졌다. 2. 일/인형 품종은 일본형 품종에 비하여 엽초의 이상신장량이 적고 침수후 초장 신장의 억제 및 분벽력의 감소가 적었다. 3. 침수에 의한 임실장해가 가장 심한 시기는 청수와 탁수 모두 출수기이었으며 특히 출수전의 수잉기말에서 출수후 개화하기 전이었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.283-283
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• 2022

Abiotic stresses such as high/low temperature, drought, salinity, and submergence directly or indirectly influence the physiological status and molecular mechanisms of rice which badly affect yield. Especially, the low temperature causes harmful influences in the overall process of rice growth such as uneven germination and the establishment of seedlings, which has become one of the main limiting factors affecting rice production in the world. It is of great significance to find the candidate genes controlling low-temperature tolerance during seed germination and study their functions for breeding new rice cultivars with immense low-temperature tolerance during seed germination. In this study, 120 lines of Cheongcheong/Nagdong double haploid population were used for quantitative trait locus analysis of low-temperature germinability. The results showed significant difference in germination under low different temperature conditions. In total, 4 QTLs were detected on chromosome 3, 6, and 8. A total of 41 genes were identified from all the 4 QTLs, among them, 25 genes were selected by gene function annotation and further screened through quantitative real time polymerase chain reaction. Based on gene function annotation and level of expression under low-temperature, our study suggested OsGPq3 gene as a candidate gene controlling viviparous germination, ABA and GA signaling under low-temperature. This study will provide a theoretical basis for marker-assisted breeding.

• 한국작물학회지
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• 제34권3호
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• pp.270-273
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• 1989

벼 품종의 관수저항성 관련 특성을 검토코자 24일묘를 3일간 관수처리하여 뿌리와 엽신의 POD 비활성도 및 POD 동위효소들을 PAGIF법으로 전기영동하여 본 결과 관수저항성이 상대적으로 약한 일본형품종들은 통일형이나 인도형품종들보다 POD 비활성도가 높았으며 또한 관수처리로 일본형품종들의 엽신부에서는 무관수시 어느 부위에서도 나타나지 않았던 POD 동위효소의 특이 band가 등전점 9부근에서 출현하였다.