• Journal of Applied Biological Chemistry
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• v.55 no.2
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• pp.71-77
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• 2012

Many of biochemical or physiological processes can be regulated by non-coding RNAs as well as coding RNAs in plants, animals and microbes. Recently, many small RNAs including microRNAs (miRNAs) and endogenous small interference RNAs (siRNAs) and long non-coding RNAs have been discovered from ubiquitous organisms including plants. Biotic and abiotic stresses are main causal agents of crop losses all over the world. Much efforts have been performed for understanding the complex mechanism of stress responses. Up to date, many of these researches have been related with the identification and investigation of stress-related proteins, showing limitation to resolve the complex mechanism. Recently, non-coding RNAs as well as coding genes have been gradually interested because of its potential roles in plant stress responses as well as other biophysical aspects. In this review, various potential roles of non-coding RNAs, especially miRNAs and siRNAs, are reviewed in relation with plant biotic and abiotic stresses.

• Journal of Ecology and Environment
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• v.44 no.4
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• pp.256-263
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• 2020

Background: Ambrosia trifida is a highly invasive annual plant, but effective control methods have not been proposed. Among various eradication methods, cutting is a simple measure to control invasive plants, and sowing seeds of native plants may effectively increase biotic resistance to invasion. In this study, we conducted a field experiment with two treatments: cutting and sowing seeds of six native or naturalized plants. Results: We found a significantly lower A. trifida abundance after cutting than in the control (77% decrease). Sowing seeds of native species did not provide any additional benefit for the control of A. trifida, but increased the importance values and diversity of other native vegetation. The abundance of A. trifida was negatively correlated with that of other plant taxa based on plant cover, biomass, and density. However, biotic resistance of sown plants was not effective to control invasion because A. trifida was so competitive. Conclusions: We concluded that cutting is an effective measure to control Ambrosia trifida while sowing seeds of native plants can increase native plant diversity.

• Journal of Korean Society on Water Environment
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• v.39 no.4
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• pp.269-287
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• 2023

The genus-level biotic index of benthic macroinvertebrates (Benthic Macroinvertebrates Genus Index, BMGI) was developed and applicated based on the data collected from 13,347 sampling units of 814 sites from 2010 to 2021 in Korea. Tolerant values of 274 indicator taxa were established by analyzing the relationship between the relative frequency and abundance of indicator taxa and the water quality index considering biochemical oxygen demand (BOD₅), total suspended solids (TSS), and total phosphorus (T-P). BMGI showed a slightly higher correlation with water quality than the species-level biotic index (Benthic Macroinvertebrates Index, BMI) that was developed and applied in Korea. Although the BMGI does not contain species-level information, the reason why BMGI shows higher applicability than BMI seems to be due to the increase in the number of indicator taxa and the decrease in the misidentification of immature aquatic insects. The coefficient of determination in multiple regression with BOD₅, TSS, and TP for BMGI was 0.62 in the long-term averaged data of 814 sites, and the standardized coefficient of BOD₅ was -0.46, TSS was -0.17 and T-P was -0.21, respectively. As a result of the evaluation by BMGI, of the 814 sites, 38% were in good, 25% in fair, and 37% in poor condition.

• Journal of Plant Biotechnology
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• v.43 no.3
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• pp.317-331
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• 2016

Development of disease resistant plant is one of the important objectives in rice breeding programs because biotic stresses can adversely affect rice growth and yield losses. This study was conducted to identify lines with multiple-resistance genes to biotic stress among 173 hybrid rice breeding lines and germplasms using DNA-based markers. Our results showed that one hybrid rice line [IR98161-2-1-1-k1-3 (IR86409-3-1-1-1-1-1/IRBB66)] possessed 5 bacterial blight resistance genes (Xa4, xa5, Xa7, Xa13 and Xa21) while two hybrid rice lines [IR98161-2-1-1-k1-2 (IR86409-3-1-1-1-1-1/IRBB66) and 7292s (IR75589-31-27-8-33S(S1)/IR102758B)] possessed 3 bacterial blight resistance genes (Xa4, Xa7 and Xa21, and Xa3, Xa4 and xa5). Molecular survey on rice blast disease revealed that most of these lines had two different resistant genes. Only 11 lines possessed Pib, Pi-5, and Pi-ta. In addition, we further surveyed the distribution of insect resistant genes, such as Bph1, Bph18(t), and Wbph. Three hybrid breeding lines [IR98161-2-1-1-k1-3 (IR86409-3-1-1-1-1-1/IRBB66), IR98161-2-1-1-k1-2 (IR86409-3-1-1-1-1-1/IRBB66), and 7292s (IR75589-31-27-8-33S(S1) /IR102758B)] contained all three resistance genes. Finally, we obtained four hybrid rice breeding lines and germplasms [IR98161-2-1-1-k1-2 (IR86409-3-1-1-1-1-1/IRBB66), Damm-Noeub Khmau, 7290s, and 7292s (IR75589-31-27-8-33S(S1)/IR102758B)] possessing six-gene combination. They are expected to provide higher level of multiple resistance to biotic stress. This study is important for genotyping hybrid rice with resistance to diverse diseases and pests. Results obtained in this study suggest that identification of pyramided resistance genes is very important for screening hybrid rice breeding lines and germplasms accurately for disease and pest resistance. We will expand their cultivation safely through bioassays against diseases, pests, and disaster in its main export countries.

• Journal of Life Science
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• v.19 no.1
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• pp.129-137
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• 2009

Calcium ($Ca^{2+}$) plays pivotal roles as an intracellular second messenger in response to a variety of stimuli, including light, abiotic. and biotic stresses and hormones. $Ca^{2+}$ sensor is $Ca^{2+}$-binding protein known to function in transducing signals by activating specific targets and pathways. Among $Ca^{2+}$-binding proteins, calmodulin (CaM) has been well reported to regulate the activity of down-stream target proteins in plants and animals. Especially plants possess multiple CaM genes and many CaM target proteins, including unique protein kinases and transcription factors. Thus, plants are possible to perceive different signals from their surroundings and adapt to the changing environment. However, the function of most of CaM or CaM-related proteins have been remained uncharacterized and unknown. Hence, a better understanding of the function of these proteins will help in deciphering their roles in plant growth, development and response to environmental stimuli. This review focuses on $Ca^{2+}$-CaM messenger system, CaM-associated proteins and their role in responses to external stimuli of both abiotic and biotic stresses in plants.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.6
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• pp.908-926
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• 2014

This study investigated the community structure and health assessment of macrobenthic assemblages in Wonmun Bay, in the southern coast of Korea. The total number of species and mean density were 170 species and $1,269\;indivuduals/m^2$, respectively. The major dominant species were the bivalve Theora fragilis ($230{\pm}446\;indivuduals/m^2$) and the polychaetes Lumbrineris longifolia ($180{\pm}339\;indivuduals/m^2$), Sigambra tentaculata ($124{\pm}153\;indivuduals/m^2$), Paraprionospio patiens ($104{\pm}293\;indivuduals/m^2$) and Capitella capitata ($82{\pm}223\;indivuduals/m^2$). Community statistics [cluster analysis and nonmetric multidimentional scaling (NMDS) ordination] revealed that the macrobenthic community structure in the study area was classified into three station groups for both seasons. Several biotic indices based on macrobenthic communities have been developed to assess the ecological quality of coastal ecosystems. In this study, the ecological status was assessed by four biotic indices Shannon's H', the AZTI Marine Biotic Index (AMBI), multivariate-AMBI (M-AMBI) and the Ecological Conservation Index (ECI). The ecological statuses of the macrobenthic communities in Wonmun Bay were poorer in the summer than in the spring. The results of the present study indicate that three biotic indices ( i.e.; Shannon's H', M-AMBI and ECI ) were better correlated with bottom dissolved oxygen than the AMBI in Wonmun Bay.

• Research in Plant Disease
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• v.24 no.3
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• pp.221-232
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• 2018

Rhizobacteria play important roles in plant growth and health enhancement and render them resistant to not only biotic stresses but also abiotic stresses, such as low/high temperature, drought, and salinity. This study aimed to select plant growth promoting rhizobacteria (PGPR) with the capability to mitigate biotic and abiotic stress effects on tomato plants. We isolated a novel PGPR strain, Variovorax sp. PMC12 from tomato rhizosphere. An in vitro assay indicated that strain PMC12 produced ammonia, indole-3-acetic acid (IAA), siderophore, and 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, which are well-known traits of PGPR. The aboveground fresh weight was significantly higher in tomato plants treated with strain PMC12 than in non-treated tomato plants under various abiotic stress conditions including salinity, low temperature, and drought. Furthermore, strain PMC12 also enhanced the resistance to bacterial wilt disease caused by Ralstonia solanacearum. Taken together, these results indicated that strain PMC12 is a promising biocontrol agent and a biostimulant to reduce the susceptibility of plants to both abiotic and biotic stresses.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2001.12a
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• pp.45-45
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• 2001

• Proceedings of the Korean Society of Crop Science Conference
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• 2002.10a
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• pp.34-37
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• 2002

• Natural Product Sciences
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• v.10 no.5
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• pp.248-251
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• 2004

Resveratrol has been reported to possess a variety of biological and pharmaceutical activities. Regardless of its beneficial effects on health, the amount of resveratrol in grapes is very low. In order to induce the resveratrol biosynthesis, the promoter region of a genomic fragment encoding the resveratrol synthase was isolated and a molecular switch was identified which provides us with defining biotic or abiotic inducers that transcriptionally up-regulate the gene expression involved in the resveratrol biosynthesis. We could successfully increase the amount of resveratrol in grapes up to 3-fold by using these environmental factors.