• Journal of Plant Biotechnology
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• v.4 no.1
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• pp.7-15
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• 2002

Eight cDNAs corresponding to fruit-specific genes were isolated from ripened melon through differential screening. Sequence comparison indicated that six of these cDNAs encoded proteins were previously characterized into aminocyclopropane-1-carboxylate (ACC) oxidase, abscisic acid, stress and ripening inducible (ASR) gene, RINC-H2 zinc finger protein, pyruvate decarboxylase, or polyubiquitin. RFS2 and RFS5 were the same clone encoding polyubiquitin. The other cDNAs showed no significant homology with known protein sequences. The ASR homologue (Asr1) gene was further characterized on the cDNA and genomic structure. The deduced amino acid sequence had similar characteristics to other plant ASR. The Asr1 genomic DNA consisted of 2 exons and 1 intron, which is similar to the structure of other plants ASR genes. The promoter region of the Asr1 gene contained several putative functional cis-elements such as an abscisic acid responsive element (ABRE), an ethylene responsive element (ERE), a C-box or DPBf-1 and 2, Myb binding sites, a low temperature responsive element (LTRE) and a metal responsive element (MRE). The findings imply that these elements may play important roles in the response to plant hormones and environmental stresses in the process of fruit development. The results of this study suggest that the expressions of fruit specific and ripening-related cDNAs are closely associated with the stress response.

• The Plant Pathology Journal
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• v.40 no.5
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• pp.512-524
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• 2024

Transcription factors (TFs) regulate gene expression by binding to DNA. The NAC gene family in plants consists of crucial TFs that influence plant development and stress responses. The whole genome of Capsicum annuum shows over 100 NAC genes (CaNAC). Functional characteristics of the most CaNAC TFs are unknown. In this study, we identified CaNAC4, a novel NAC TF in C. annuum. CaNAC4 expression increased after inoculation with the pathogens, Xanthomonas axonopodis pv. vesicatoria race 3 and X. axonopodis pv. glycines 8ra, and following treatment with the plant hormones, salicylic acid and abscisic acid. We investigated the functional characteristics of the CaNAC4 gene and its roles in salt tolerance and anti-pathogen defense in transgenic Nicotiana benthamiana. For salt stress analysis, the leaf discs of wild-type and CaNAC4-transgenic N. benthamiana plants were exposed to different concentrations of sodium chloride. Chlorophyll loss was more severe in salt stress-treated wild-type plants than in CaNAC4-transgenic plants. To analyze the role of CaNAC4 in anti-pathogen defense, a spore suspension of Botrytis cinerea was used to infect the leaves. The disease caused by B. cinerea gradually increased in severity, and the symptoms were clearer in the CaNAC4-transgenic lines. We also investigated hypersensitive response (HR) in CaNAC4-transgenic plants. The results showed a stronger HR in wild-type plants after infiltration with the apoptosis regulator, BAX. In conclusion, our results suggest that CaNAC4 may enhance salt tolerance and act as a negative regulator of biotic stress in plants.

• Journal of Applied Biological Chemistry
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• v.51 no.3
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• pp.83-87
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• 2008

Tension wood, a specialized tissue developed in the upper side of the leaning stem and drooping branches of angiosperm, is an attractive experimental system attractive for exploring the development and the biochemical pathways of the secondary cell wall formation, as well as the control mechanism of the carbon flux into lignin, cellulose, and hemicellulose. However, the mechanism underlying the induction and the development of the tension wood is largely unknown. Recently, several researchers suggested the possible roles of the plant growth hormones including auxin, gibberellin, and ethylene mainly based on the expression pattern of the genes in this specialized tissue. In addition, expressed sequence tag of Poplar and Eucalyptus provide global view of the genetic control underlying the tension wood formation. However, the roles of the majority of the identified genes have not yet been clearly elucidated. The present review summarized current knowledge on the biosynthesis of tension wood to provide a brief synopsis of the molecular mechanism underlying the development of the tension wood.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.1
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• pp.1-4
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• 1991

This is study was conducted to find out the effect of various plant hormones on the growth of garlic callus and to determine the effects of sulfur and nitrogen on the formation of alliin. The following results were obtained. The callus was grown effectively on the basal Linsmainer and skoog medium supplemented with 10-6M of kinetin and 2, 4-dichlorophenoxyacetic acid. When alliin produced by callus were extracted and identified by PPC allin appeared to have Rf value 0.21 in PPC which was exactly same as standard and it gave a deep red colar by Grot's reagent. The highest amount of alliin which is produced in callus culture was 270mg per 100g of dry weight in the basal Linsmaier and Skoog medium supplemented with 100% of NO3 as a nitrogen source.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.23 no.3
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• pp.2-4
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• 1978

Some of the remarkable accomplishments mentioned in the special lecture recalling 38 years of my research on the development of herbicides can be summarized as follows; 1) The physiology, movement in the soil, and decomposition and/or inactivation of the phenoxy and other herbicides by the invention of the Raphanus test were elucidated. And these findings led to the establishment of the theory of herbicidal treatment layer with the result of the origination of the application of PCP in flooded lowland paddy, which opened new era of soil application of herbicides in lowland paddy. 2) The granulation of herbicides for lowland paddy including PCP urea was developed. 3) The fact that propanil has generic selectivity in gramineae was found. And propanil was distributed in rice growing regions of the world. In addition, satanil for upland and propanil/NAC for flooded lowland paddy, propanil mixtures, were developed. 4) 15 kinds of new herbicides derived from plant hormones developed in my laboratory were develop ed, and the research trends in the future were presented.

• Korean Journal of Pharmacognosy
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• v.27 no.3
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• pp.262-266
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• 1996

Undifferentiated callus were induced from the young leaves of Taxus cuspidata by treatment with various combinations of plant growth hormones. The effects of light and culturing temperature on production of baccatin III, the precursor of taxol, were studied. The contents of baccatin III in the cultured callus were analysed by HPLC. The illumination of fluorescence and administration of isoleucine, one of the possible substrates in biosynthesis of terpenoids, to the culturing media increased the production of baccetin III.

• Microbiology and Biotechnology Letters
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• v.21 no.6
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• pp.609-614
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• 1993

The optimum conditions for the submerged mycelial culture of Lentinus edodes SR-1 were elucidated to be incubation temperature of 25C, initial pH 4.0, agitation of 300 rpm, inoculation of 10.0%(v/v), and aeration of 1.0 v/v/m in TGY medium. The optimum c/n ratio and economic yield coeffcient for the submerged mycelial culture were 13.1:1 and 0.45 respectively. As the plant growth hormones test, SCM medium containing 0.5ppm of 2,4-dicholorophenoxyacetic acid increased mycelial yield in 1.1%, but 6-benzylaminopurine was not effective.

• Food Science of Animal Resources
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• v.25 no.1
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• pp.66-70
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• 2005

This study was conducted to determine the effects of MgSO₄ supplement on meat quality and serum stress hormones concentrations in late finishing pigs. Sixty castrated Landrace pigs (average weight±S.D., 106.5±8.9 kg) were assigned to a control diet (without MgSO₄ supplement) and diet with MgSO₄(10 g/kg diet) supplemented. Pigs had free access to diets and water during five-day feeding period. At the end of feeding experiment, pigs were fasted for 16 hours and transported to commercial slaughter plant (30-minute transportation distance). After 2-hour lairage time, pigs were slaughtered, and blood samples were collected at bleeding procedure of slaughter. Pigs fed the diet with MgSO₄ supplement had higher (p<0.05) serum magnesium concentrations than those in pigs fed a control diet. Serum adrenaline, noradrenaline and cortisol concentrations determined at slaughter were not significantly different between dietary groups. Carcass temperature, pH at 24h post- slaughter, drip loss and color characteristics were not influenced (p>0.05) by short-term supplement of MgSO₄. Pigs fed the diet supplemented with MgSO₄ diet had lower PSE incidence (23.3%) compared to pigs fed the control diet (33%). These results indicate that short-term supplement of dietary MgSO₄ in late finishing pigs may not be beneficial in improving pork quality, and further study needs to assess feeding regime of magnesium supplement.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.spc
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• pp.20-28
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• 2009

The sustainability of conventional agriculture which is characterized by input dependent and ecologically simplified food production system is vague. Chemicals and present practices used in agriculture are not only costly but also have widespread implications on human and animal health, food quality and safety and environmental quality. Thus there is a need for alternative farming practices to sustain food production for the escalating population and conserve environment for future generations. The present research scenario in the area of plant microbe interactions for maintaining sustainable agriculture suggests that the level of internal regulation in agro-ecosystems is largely dependent on the level of plant and microbial diversity present in the soil. In agro-ecosystems, biodiversity performs a variety of ecological services beyond the production of food, including recycling of nutrients, regulation of microclimate and local hydrological processes, suppression of undesirable organisms and detoxification of noxious chemicals. Controlling the soil microflora to enhance the predominance of beneficial and effective microorganisms can help improve and maintain soil chemical and physical properties. The role of beneficial soil microorganisms in sustainable productivity has been well construed. Some plant bacteria referred to as plant growth-promoting rhizobacteria (PGPR) can contribute to improve plant growth, nutrient uptake and microbial diversity when inoculated to plants. Term PGPR was initially used to describe strains of naturally occurring non-symbiotic soil bacteria have the ability to colonize plant roots and stimulate plant growth PGPR activity has been reported in strains belonging to several other genera, such as Azotobacter, Azospirillum, Arthrobacter Bacillus, Burkhokderia, Methylobacterium, and Pseudomonas etc. PGPR stimulate plant growth directly either by synthesizing hormones such as indole acetic acid or by promoting nutrition, for example, by phosphate solubilization or more generally by accelerating mineralization processes. They can also stimulate growth indirectly, acting as biocontrol agents by protecting the plant against soil borne fungal pathogens or deleterious bacteria. Present review focuses on some recent developments to evolve strategies for better biotechnological exploitation of PGPR's.

• Journal of Microbiology and Biotechnology
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• v.25 no.9
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• pp.1467-1475
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• 2015

The use of microbial extracts containing plant hormones is a promising technique to improve crop growth. Little is known about the effect of bacterial cell-free extracts on plant growth promotion. This study, based on phytohormonal analyses, aimed at exploring the potential mechanisms by which Enterococcus faecium LKE12 enhances plant growth in oriental melon. A bacterial strain, LKE12, was isolated from soil, and further identified as E. faecium by 16S rDNA sequencing and phylogenetic analysis. The plant growth-promoting ability of an LKE12 bacterial culture was tested in a gibberellin (GA)-deficient rice dwarf mutant (waito-C) and a normal GA biosynthesis rice cultivar (Hwayongbyeo). E. faecium LKE12 significantly improved the length and biomass of rice shoots in both normal and dwarf cultivars through the secretion of an array of gibberellins (GA₁, GA₃, GA₇, GA₈, GA₉, GA₁₂, GA₁₉, GA₂₀, GA₂₄, and GA₅₃), as well as indole-3-acetic acid (IAA). To the best of our knowledge, this is the first study indicating that E. faecium can produce GAs. Increases in shoot and root lengths, plant fresh weight, and chlorophyll content promoted by E. faecium LKE12 and its cell-free extract inoculated in oriental melon plants revealed a favorable interaction of E. faecium LKE12 with plants. Higher plant growth rates and nutrient contents of magnesium, calcium, sodium, iron, manganese, silicon, zinc, and nitrogen were found in cell-free extract-treated plants than in control plants. The results of the current study suggest that E. faecium LKE12 promotes plant growth by producing GAs and IAA; interestingly, the exogenous application of its cell-free culture extract can be a potential strategy to accelerate plant growth.