• Journal of Plant Biotechnology
• /
• v.8 no.1
• /
• pp.27-35
• /
• 2006

Plantlet regeneration in Asteracantha longifolia(L.) Nees (Acanthaceae), a medicinal herb has been achieved from seedling explants on basal MS medium. Three different seedling explants including node, internode and leaf segments on used. Of these three explant, leaf explants gave better response for both callus mediated organogenesis and direct multiple shoot induction. Number of explants showing differentiation of shout buds was higher on MS media supplemented with BA compared to kinetin. MS medium fortified with BA ($2.0mgl^{-1}$) and NAA ($0.5mgl^{-1}$) was found to be most suitable for both callus mediated organogenesis and elongation of shouts. The elongated shoots were successfully routed on MS medium fortified with NAA or IBA. Among them $0.1mgl^{-1}$ NAA or $0.2mgl^{-1}$ IBA provides better response for rhizogenesis. Regenerated plantlets were successfully established in soil where 85.4% or them developed into morphologically normal and fertile plants. RAPD profiling using four decamer primers confirmed the genetic uniformity of the regenerated plantlets and substantiated the efficacy and suitability of this protocol for in vitro propagation of A. longifolia.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.65 no.12
• /
• pp.2251-2261
• /
• 2016

The use of renewable energy sources and energy storage systems is increasing due to new policies in the energy industries. However, the increase in distributed generation hinders the reliability of power systems. In order to stabilize power systems, a virtual power plant has been proposed as a novel power grid management system. The virtual power plant plays includes different distributed energy resources and energy storage systems. We define a core virtual power plant technology related to demand response and ancillary service for the cases of Korea, America, and Europe. We also suggest applications of the proposed virtual power plant to the vehicle-to-grid market for restructuring national power industries in Korea.

• The Plant Pathology Journal
• /
• v.35 no.3
• /
• pp.257-273
• /
• 2019

Tomato (Solanum lycopersicum) is one of the most widely grown and economically important vegetable crops in the world. Tomato chlorosis virus (ToCV) is one of the recently emerged viruses of tomato distributed worldwide. ToCV-tomato interaction was investigated at the molecular level for determining changes in the expression of tomato genes in response to ToCV infection in this study. A cDNA library enriched with genes induced in response to ToCV infection were constructed and 240 cDNAs were sequenced from this library. The macroarray analysis of 108 cDNAs revealed that the expression of 92 non-redundant tomato genes was induced by 1.5-fold or greater in response to ToCV infection. The majority of ToCV-induced genes identified in this study were associated with a variety of cellular functions including transcription, defense and defense signaling, metabolism, energy, transport facilitation, protein synthesis and fate and cellular biogenesis. Twenty ToCV-induced genes from different functional groups were selected and induction of 19 of these genes in response to ToCV infection was validated by RT-qPCR assay. Finally, the expression of 6 selected genes was analyzed in different stages of ToCV infection from 0 to 45 dpi. While the expression of three of these genes was only induced by ToCV infection, others were induced both by ToCV infection and wounding. The result showed that ToCV induced the basic defense response and activated the defense signaling in tomato plants at different stages of the infection. Functions of these defense related genes and their potential roles in disease development and resistance to ToCV are also discussed.

• Molecules and Cells
• /
• v.24 no.3
• /
• pp.394-408
• /
• 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.

• The Plant Pathology Journal
• /
• v.23 no.2
• /
• pp.76-89
• /
• 2007

CaCDPK4, a full-length cDNA clone encoding Capsicum annuum calcium-dependent protein kinase 4, was isolated from chili pepper (Capsicum annuum L.). Deduced amino acid sequence of CaCDPK4 shares the highest homology with tobacco NpCDPK8 and chickpea CaCDPK2 with 79% identity. Genomic blot analyses revealed that CaCDPK4 is present as a single copy in pepper genome, but it belongs to a multigene family. CaCDPK4 was highly induced when pepper plants were inoculated with an incompatible bacterial pathogen. Induced levels of CaCDPK4 transcripts were also detected in pepper leaves by the treatment of ethephon, an ethylene-inducing agent, and high-salt stress condition. The bacterial-expressed GST-CaCDPK4 protein showed to retain the autophosphorylation activity in vitro. GUS expression driven by CaCDPK4 promoter was examined in transgenic Arabidopsis containing transcriptional fusion of CaCDPK4 promoter. GUS expression under CaCDPK4 promoter was strong in the root and veins of the seedlings. GW (-1965) and D3 (-1377) promoters conferred on GUS expression in response to inoculation of an incompatible bacterial pathogen, but D4-GUS (-913) and DS-GUS (-833) did not. Taken together, our results suggest that CaCDPK4 can be implicated on signal transduction pathway of defense response against an incompatible bacterial pathogen in pepper.

• Korean Journal of Agricultural Science
• /
• v.40 no.4
• /
• pp.395-403
• /
• 2013

Plant factory has drawn attention in many countries in the world due to capability of environmental control not only for better yield and quality, but also for increase in functional and medicinal components of the products. In this paper, an experimental plant factory was constructed for various tests under different environmental conditions, and the operations were evaluated. A production room was constructed with adiabatic materials with dimensions of $6,900{\times}3,000{\times}2,500$ mm ($L{\times}W{\times}H$). Four sets of $2,890{\times}600{\times}2,320$ mm ($L{\times}W{\times}H$) production frame unit, each with 9 light-installed beds and an aeroponic fertigation system, resulting in 36 beds, were prepared. Accuracy and response were evaluated for each environmental control component with and without crops. Air temperature, humidity, $CO_2$ concentration, light intensity, frequency, and duty ratio, fertigation rate and scheduling were controllable from a main control computer through wireless communication devices. When the plant factory was operated without crop condition, the response times were 8 minutes for change in temperature from 20 to $15^{\circ}C$ and 20 minutes from 15 to $20^{\circ}C$; 7 minutes for change in humidity from 40 to 65%; and 4 minutes for change in $CO_2$ concentration from 450 to 1000 ppm. When operated for 24 hours with crop cultivation; average, maximum, and minimum values of temperatures were 20.06, 20.8, and $18.8^{\circ}C$; humidity were 66.72, 69.37, and 63.73%; $CO_2$ concentrations were 1017, 1168, and 911 ppm, respectively. Photosynthetic Photon Flux Density was increased as the distance from the light source decreased, but variability was greater at shorter distances. Results of the study would provide useful information for efficient application of the plant factory and to investigate the optimum environment for crop growth through various experiments.

• Journal of Crop Science and Biotechnology
• /
• v.10 no.3
• /
• pp.147-158
• /
• 2007

Xanthomonas axonopodis pv. glycines(Xag) is a pathogen that causes bacterial leaf pustule(BLP) disease in soybeans grown in Korea and the southern United States. Typical and early symptoms of the disease are small, yellow to brown lesions with raised pustules that develop into large necrotic lesions leading to a substantial loss in yield due to premature defoliation. After Xag infects PI 96188, only pustules without chlorotic haloes were observed, indicating the different response to Xag. To identify differentially expressed genes prior to and 24 hr after Xag inoculation to PI 96188 and BLP-resistant SS2-2, an oligonucleotide macroarray was constructed with 100 genes related to disease resistance and metabolism from soybean and Arabidopsis. After cDNAs from each genotype were applied on the oligonucleotide macroarrays with three replicates and dye swapping, 36 and 81 genes were expressed as significantly different between 0 hr and 24 hr in PI 96188 and SS2-2, respectively. Six UniGenes, such as the leucine-rich repeat protein precursor or 14-3-3-like protein, were selected because they down-regulated in PI 96188 and up-regulated in SS2-2 after Xag infection, simultaneously. Using tubulin and cDNA of Jangyeobkong(BLP-susceptible) as controls, the oligonucleotide macroarray data concurred with quantitative real-time RT-PCR(QRT RT-PCR) results in most cases, supporting the accuracy of the oligonucleotide macroarray experiments. Also, QRT RT-PCR data suggested six candidate genes that might be involved in a necrotic response to Xag in PI 96188.

• The Plant Pathology Journal
• /
• v.32 no.4
• /
• pp.357-362
• /
• 2016

ALD1 (ABERRANT GROWTH AND DEATH2 [AGD2]-LIKE DEFENSE1) is one of the key defense regulators in Arabidopsis thaliana and Nicotiana benthamiana. In these model plants, ALD1 is responsible for triggering basal defense response and systemic resistance against bacterial infection. As well ALD1 is involved in the production of pipecolic acid and an unidentified compound(s) for systemic resistance and priming syndrome, respectively. These previous studies proposed that ALD1 is a potential candidate for developing genetically modified (GM) plants that may be resistant to pathogen infection. Here we introduce a role of ALD1-LIKE gene of Oryza sativa, named as OsALD1, during plant immunity. OsALD1 mRNA was strongly transcribed in the infected leaves of rice plants by Magnaporthe oryzae, the rice blast fungus. OsALD1 proteins predominantly localized at the chloroplast in the plant cells. GM rice plants over-expressing OsALD1 were resistant to the fungal infection. The stable expression of OsALD1 also triggered strong mRNA expression of PATHOGENESIS-RELATED PROTEIN1 genes in the leaves of rice plants during infection. Taken together, we conclude that OsALD1 plays a role in disease resistance response of rice against the infection with rice blast fungus.

• The Plant Pathology Journal
• /
• v.30 no.3
• /
• pp.254-260
• /
• 2014

Potato Rpi-blb2 encodes a protein with a coiled-coil-nucleotide binding site and leucine-rich repeat (CC-NBSLRR) motif that recognizes the Phytophthora infestans AVRblb2 effector and triggers hypersensitive cell death (HCD). To better understand the components required for Rpi-blb2-mediated HCD in plants, we used virus-induced gene silencing to repress candidate genes in Rpi-blb2-transgenic Nicotiana benthamiana plants and assayed the plants for AVRblb2 effector. Rpi-blb2 triggers HCD through NbSGT1-mediated pathways, but not NbEDS1- or NbNDR1-mediated pathways. In addition, the role of salicylic acid (SA), jasmonic acid (JA), and ethylene (ET) in Rpi-blb2-mediated HCD were analyzed by monitoring of the responses of NbICS1-, NbCOI1-, or NbEIN2-silenced or Rpi-blb2::NahG-transgenic plants. Rpi-blb2-mediated HCD in response to AVRblb2 was not associated with SA accumulation. Thus, SA affects Rpi-blb2-mediated resistance against P. infestans, but not Rpi-blb2-mediated HCD in response to AVRblb2. Additionally, JA and ET signaling were not required for Rpi-blb2-mediated HCD in N. benthamiana. Taken together, these findings suggest that NbSGT1 is a unique positive regulator of Rpi-blb2-mediated HCD in response to AVRblb2, but EDS1, NDR1, SA, JA, and ET are not required.

• Journal of Plant Biotechnology
• /
• v.7 no.3
• /
• pp.161-167
• /
• 2005

Brassinosteroids are steroidal plant hormones and are known to modulate physiological and cellular response in a wide range of plant species. Considerable insights has been achieved of the physiological role of brassinosteroid in Brassica species in the past few years, but their effect on direct organogenesis has not been extensively studied. In this sense, under optimal basal media and growth conditions we tested the cellular and organogenic response of 24-epibrassinolide (EBL) in a variable concentration (0.1 to $5.0\;{\mu}M$) and Zeatin (Z) (1.0 to $100\;{\mu}M$) and their synergic effect on hypocotyl explants of cauliflower and broccoli. The isolated EBL accelerated cell elongation and promotes direct organogenesis. One micromolar EBL + $10\;{\mu}M$ of Z was the most efficient combination for cell elongation, cell differentiation as well as for organogenesis. A suppressing effect on root induction was confirmed for all the tested hormone levels. The general results indicate a synergic effect of EBL-Z and EBL potentates Zeatin activity, at least in certain tissues. Besides de genetic factors, we can speculate that the natural hormone concentration in the explants might affect the responses by application of exogenous growth regulators. Experiments with new plant growth regulators, like brassinolide, are important aiming to maximize or accelerate plant regeneration for in vitro multiplication or for genetic transformation.