• Korean Journal of Plant Resources
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• v.30 no.5
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• pp.571-577
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• 2017

Abscisic acid (ABA) is an important phytohormone involved in abiotic stress tolerance in plants. The group A bZIP transcription factors play important roles in the ABA signaling pathway in Arabidopsis but little is known about their functions in rice. In our current study, we have isolated and characterized a group A bZIP transcription factor in rice, OsABF3 (Oryza sativa ABA responsive element binding factor 3). We examined the expression patterns of OsABF3 in various tissues and time course analysis after abiotic stress treatments such as drought, salinity, cold, oxidative stress, and ABA in rice. Subcellular localization analysis in maize protoplasts using a GFP fusion vector further indicated that OsABF3 is a nuclear protein. Moreover, in a yeast one-hybrid experiment, OsABF3 was shown to bind to ABA responsive elements (ABREs) and its N-terminal region found to be necessary to transactivate a downstream reporter. A homozygous T-DNA insertional mutant of OsABF3 is more sensitive to salinity, drought, and oxidative stress compared with wild type plants ＆ OsABF3OX plants. In addition, this Osabf3 mutant showed a significantly decreased sensitivity to high levels of ABA at germination and post-germination. Collectively, our present results indicate that OsABF3 functions as a transcriptional regulator that modulates the expression of abiotic stress-responsive genes through an ABA-dependent pathway.

• 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.

• Journal of Plant Biotechnology
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• v.44 no.1
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• pp.82-88
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• 2017

Transgenic lily plants have been obtained after particle bombardment, using PDS-1000/He system and scale explants of lilies, followed by PPT (D-L-phosphinothricin) selection. In this study, scales of the lily plants cv. 'red flame' were bombarded with a plasmid containing the bar gene as a selectable marker, and the AtSIZ gene as a gene of interest, showing salt tolerance and drought tolerance respectively, and both being driven by the CaMV 35S promoter. For optimization of a protocol, factors which optimized and showed a high transformation efficiency under following conditions, were considered: a bombardment pressure of 1100 psi, a target distance of 6 cm and $1.0{\mu}m$ of gold particle, and 24-h pre-culture and post-culture on MS medium containing 0.2 M sorbitol and 0.2 M mannitol as osmoticum agents. After bombardment, all the bombarded scales of lily were transferred to MS medium without selective agents, for a week. Subsequently, these bombarded scales were transferred to a selection MS medium containing 10 mg/l PPT, and incubated for a month for further selection, after which they were cultured for another 4-8 weeks with a 4-week subculture regime on the same selection medium. After transferring into hormone-free MS medium, the PPT-resistant scales with shoots were successfully rooted and regenerated into plantlets. PCR analysis revealed that the surviving putatively transformed plantlets indicated the presence of both the bar gene and the AtSIZ gene. In conclusion, when 100 scales of lily cv. Red flame are bombarded, this study produced approximately 17-18 transgenic plantlets with an optimized bombardment protocol. The protocol described here can contribute to the breeding program of lilies.

• Ecology and Resilient Infrastructure
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• v.6 no.3
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• pp.163-170
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• 2019

The civil engineering materials used to stabilize the slopes of new riverbanks have a great impact on the types and growth of vegetation introduced after the completion of construction procedure. Recently, microbial-derived, ${\beta}$-glucan- and xanthan gum-based biopolymers are attracting attention as an ecofriendly strengthening material of riverbanks that can possibly stimulate plant growth. This study aimed to assess ecological effects of biopolymer application on native plants in Korean riverbanks. In particular, since dominant plant species could shape characteristics of an ecosystem, we examined the effects of biopolymer on the dominant plant species in riverbanks. Overall, biopolymer did not affect seed germination rates of testing plant species. In contrast, plants grew more vigorously in the soil mixed with biopolymer compared to those in the control soil. The biomass of Echinochloa crus-galli especially increased around two times more in the biopolymer treatment. Plants produced heavier root biomass and leaves with larger specific leaf area, which possibly contributes to the tolerance of environmental stress like drought. These results suggest that biopolymers treated on river banks are expected to stimulate plant growth and increase stress tolerance of domestic dominant plant species.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.77.2-78
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• 2003

An EREBP/AP2-type transcription factor (CaPFl) was isolated by DDRT-PCR following inoculation of soybean pustule pathogen Xanthomonas axonopodis pv. glycines Bra which induces HR on pepper leaves. Genomic Southern blot analysis revealed that the CaPFl gene is present as a single copy within the hot pepper genome. The deduced amino acid sequence of CaPFl has two potential nuclear localization signals, a possible acidic activation domain, and an EREBP/AP2 motif that could bind to a conserved cis- element present in promoter region of many stress-induced genes. The mRNA level of CaPFl was induced by both biotic and abiotic stresses. We observed higher-level transcripts in resistance-induced pepper tissues than diseased tissues. Expression of CaPFl is also induced upon various abiotic stresses including ethephon, MeJA, cold stress, drought stress and salt stress treatments. To study the role of CPFI in plant, transgenic Arabidopsis and tobacco plants which express higher level of pepper CaPFl were generated. Global gene expression analysis of transgenic Arabidopsis by cDNA microarray indicated that expression of CaPFl in transgenic plants affect the expression of quite a few GCC box and DRE/CRT box-containing genes. Furthermore, the transgenic Arabidopsis and tobacco plant, expressing CaPFl showed tolerance against freezing temperature and enhanced resistance to Pseudomonas syrnigae pv. tabaci. Taken together, these results indicated that CaPFl is a novel EREBP/AP2 transcription factor in hot pepper plant and it may has a significant role(s) in regulation of biotic and abiotic stresses in plant.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.74-74
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• 2018

Little millet (Panicum sumatrense) is well known for its salt and drought stress tolerance and high nutritional value, but very limited knowledge of genetic variation and genomic information is available. This study was to develop highly polymorphic EST-SSR markers based on cross-species transferability of derived SSRs from switchgrass EST databases and characterize newly developed EST - SSRs to better understand the genetic diversity of collected 37 germplasm accessions of little millet. A total of 779 primer pairs were designed from the 22,961 EST sequences of switchgrass (Pancium virgatum), of which 48 EST - SSR markers were developed based on the trials of transferability of these primers in little millet. The EST - SSR amplicons showed reproducible single band polymorphism and produced a total of 160 alleles with an average of 3.3 alleles per locus in 37 accessions of little millet. T he average values of expected and observed heterozygosities were 0.266 and 0.123, respectively. T he polymorphic information content (PIC) values were observed in range of 0.026 to 0.549 with an average of 0.240. The genetic relatedness among the little millet accessions was evaluated by neighbor-joining dendrogram, which grouped all accessions into two distinct groups. The validation thus demonstrated the utility of the switchgrass EST - SSR markers in assessing genomic relationships in little millet. T he findings from this study could be useful for designing strategies for the identification of diverse germplasm for conservation and future molecular breeding programs for little millet.

• Korean Journal of Agricultural Science
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• v.46 no.4
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• pp.769-779
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• 2019

Chilli peppers are predominantly cultivated in open field systems under abiotic and biotic stress conditions. Abiotic and biotic factors have a considerable effect on plant performance, fruit quantity, and quality. Chilli peppers grow well in a tropical climate due to their adaptation to warm and humid regions with temperatures ranging from 18 to 30℃. Nowadays, chilli peppers are cultivated all around the world under different climatic conditions, and their production is gradually expanding. Expected climate changes will likely cause huge and complex ecological consequences; high temperature, heavy rainfall, and drought have adverse effects on the vegetative and generative development of all agricultural crops including chilli peppers. To gain better insight into the effect of climate change, the growth, photosynthetic traits, morphological and physiological characteristics, yield, and fruit parameters of chilli peppers need to be studied under simulated climate change conditions. Moreover, it is important to develop alternative agrotechnologies to maintain the sustainability of pepper production. There are many conceivable ideas and concepts to sustain crop production under the extreme conditions of future climate change scenarios. Therefore, this review provides an overview of the adverse impacts of climate change and discusses how to find the best solutions to obtain a stable chilli pepper yield.

• Journal of Forest and Environmental Science
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• v.33 no.2
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• pp.97-104
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• 2017

Investigation was carried out on response of Tetrapleura tetraptera (Schum. and Thonn.) to soil, water and light with the view of its domestication and introduction to different ecological regions. The experiment was arranged in a factorial experiment of $3{\times}3{\times}3$ in a completely randomized design (CRD) with three replicates. The factors were: soil textural class (Loamy sand, Sand and Sandy clay loam), watering regime (daily, twice a week and once a week) and light intensity (100%, 75% and 50%). Soil textural classes had significant influence on collar diameter, stem height, number of leaflets, root/shoot ratio and relative growth rate of Tetrapleura seedlings. Seedlings grown on loamy sand recorded the highest mean value- 2.28 mm for collar diameter, stem height- 12.9 cm, number of leaflets- 19.9, chlorophyll b- $0.34mg\;mL^{-1}$, leaf relative water content- 27.4% and relative growth rate- $0.037mg\;g^{-1}\;day^{-1}$. Watering regime had significant influence on the collar diameter of Tetrapleura. Seedlings watered daily recorded the highest mean value- 2.25 mm for collar diameter. Light intensity significantly influenced collar diameter and root/shoot ratio. Seedlings exposed to 100% light intensity recorded higher mean value for collar diameter- 2.28 mm and root/shoot ratio- 1.481 cm. The interaction between soil textural class and light intensity significantly affected collar diameter, stem height and number of leaflets. Higher mean value for collar diameter (2.47 mm) stem height (13.25 cm) and number of leaflets (21.16) were recorded while the interaction between soil textural class, light intensity and watering regime was significant for only number of leaflets. Tetrapleura exhibited some level of tolerance to different soil texture, drought and light intensity. Therefore, Tetrapleura has the potentials to be raised in different ecological zones characterized by difference in soil, rainfall and amount of sunshine.

• Journal of Environmental Science International
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• v.23 no.7
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• pp.1299-1305
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• 2014

For evaluating the effect of various artificial planting soil properties on the Euonymus fortunei 'Emelad'n Gold' growth, a container green wall system experiment was conducted in a wall of greenhouse at Konkuk University, Glocal campus. The experimental artificial planting grounds were prepared with different organic soil conditioner ratios (Control, $A_4O_1$, $A_2O_1$ and $A_1O_1$) and with drought tolerance and an ornamental value Euonymus fortunei 'Emelad'n Gold' was planted. The soil and plant characteristics were investigated from April to Jun 2010. The volumetric soil moisture contents were significantly increasing order as the amount of organic soil conditioner level increased in order to $A_1O_1$ > $A_2O_1$ > $A_4O_1$ > Control. At 4 treatment, soil chemical properties were inversely related to organic soil container ratios increase. The differences of root collar caliper, number of branch, and survival rate between the organic soil conditioner ratio were not significantly affected by organic soil conditioner. But, plant height, internode length, leaf length and leaf width were significantly shorter on plants planted $A_1O_1$ than plants planted other treatments. Therefore, Euonymus fortunei 'Emelad'n Gold' had good growth response regardless of organic soil conditioner ratio and the plant is expected to be a highly valuable shrub for the green wall system if it should be considered in integration with stormwater retention or as a soil conditioner for increasing soil water contents in artificial planting soil.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.149-149
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• 2017

The RING (Really Interesting New Gene) finger proteins are known to play crucial roles in various abiotic stresses in plants. In this study, we report on RING finger E3 ligase, ${\underline{O}ryza}$ ${\underline{s}ativa}$ ${\underline{s}alt$-, ${\underline{A}BA}$- and ${\underline{d}rounght}$ stress-${\underline{i}nduced}$ RING finger ${\underline{p}}rotein{\underline{1}}$ gene (OsSAD1). In vitro ubiquitination assay demonstrated that unlike OsSAD1, a single amino acid substitution ($OsSAD1^{C168A}$) of the RING domain showed no E3 ligase activity, supporting the notion that the activity of most E3s is specified by a RING domain. Result of Yeast-Two hybridization, In vivo protein degradation assay supports that OsSAD1 interacting with 3 substrate, OsSNAC2, OsGRAS44 and OsPIRIN1, and mediates proteolysis of 3 substrates via the 26S proteasome pathway. Subcellular localizations of OsSAD1 while approximately 62% of transient signals were detected in cytosol, 38% of signals were showed nucleus. However, transiently expression of OsSAD1 was detected in cytosol 30% while as 70% of nucleus under 200 mM salt treated rice protoplasts. Results of bimolecular fluorescence complementation (BiFC) showed that two nucleus-localized proteins (OsSNAC2 and OsGRAS44) interacted with OsSAD1 in the both cytosol and nucleus. Heterogeneous overexpression of OsSAD1 Heterogeneous overexpresssion of OsSAD1 in Arabidopsis exhibited sensitive phenotypes with respect to Salt-, mannitol-responsive seed germination, seedling growth. In ABA conditions, OsSAD1 overexpression plants showed highly tolerance phenotypes, such as root length and stomatal closure. Our findings suggest that the OsSAD1 may play a negative regulator in salt stress response by modulating levels of its target proteins.