• Korean Journal of Environmental Biology
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• v.23 no.1
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• pp.47-51
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• 2005

Three-weeks old Commelina communis was transferred to Hoagland solution (Control, 100 μM Cd/sup 2+/, 100 μM Cd/sup 2+/ + 100 μM ABA, 100 μM Cd/sup 2+/+50 mM KCl) and grown for a week in the solution and then a number of physiological activities were investigated. In cases of Cd/sup 2+/ and Cd/sup 2+/ + ABA treatments, the growth of the plants was inhibited to 71 % and 81 %, respectively, when compared with the control, but there were no significant difference of plant growth between Cd/sup 2+/ and Cd/sup 2+/ + KCl- treated plants. In the treatments of Cd/sup 2+/, Cd/sup 2+/ + ABA and Cd/sup 2+/ + KCl total chlorophyll contents were reduced to 32%, 41% and 29%, respectively. In chlorophyll fluorescence experiments, Fv/Fm ratios were also reduced to 14∼20% and about 23%, respectively, according to the light intensity by Cd/sup 2+/ and Cd/sup 2+/+ABA-treated plants. Water stresses were increased by the treatment of Cd/sup 2+/, Cd/sup 2+/ + ABA and Cd/sup 2+/ + KCI. In Cd/sup 2+/ accumulation experiments Cd/sup 2+/ transport into the plant by ABA was not affected, but the accumulation of Cd/sup 2+/ into the roots was elevated to 13% when compared with the control. Cd/sup 2+/ transport into the root was markedly inhibited to 60% by KCl. Therefore, it could be concluded that ABA did not reduce the toxicities of Cd/sup 2+/, but enhanced Cd/sup 2+/ - induced toxicities and KCl showed no effect on Cd/sup 2+/ - induced toxicities.

• Journal of Plant Biotechnology
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• v.44 no.3
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• pp.264-270
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• 2017

Brassinosteroid (BR), a plant steroid hormone, plays a critical role in the growth and developmental processes through its canonical signaling and crosstalk with various internal and external signaling pathways. Recent studies have revealed the essential interplay mechanisms between BR and ABA during seed germination and early seedling establishment. However, molecular mechanisms for this important signaling crosstalk are largely unknown. To understand the crosstalk between BR-mediated signaling pathways and ABA functions during early seedling development, we carried out a comparative genome-wide transcriptome analysis with an Agilent Arabidopsis $4{\times}44K$ oligo chip. We selected and compared the expression patterns of ABA response genes in ABA-insensitive bes1-D mutant with wild type seedlings on which ABA was exogenously applied. As a result, we identified 2,353 significant differentially expressed genes (DEGs) in ABA-treated bes1-D and wild type seedlings. GO enrichment analysis revealed that ABA signaling, response, and metabolism were critically down-regulated by BR-activated signaling pathways. In addition, the genome-wide transcriptome analysis data revealed that BR-regulated signaling pathways were tightly connected to diverse signal cues including abiotic/biotic stress, auxin, ROS etc. In this study, we newly identified the molecular mechanisms of BR-mediated repression of ABA signaling outputs. Also, our data suggest that interplay among diverse signaling pathways is critical for the adaptive response of the plant to various environmental factors.

• 한국균학회소식:학술대회논문집
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• 2014.10a
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• pp.15-15
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• 2014

Fusarium graminearum (teleomorph Gibberella zeae) is an important plant pathogen that causes head blight of major cereal crops such as wheat, barley, and rice, as well as causing ear and stalk rot on maize worldwide. Plant diseases caused by this fungus lead to severe yield losses and accumulation of harmful mycotoxins in infected cereals [1]. Fungi utilize spore production as a mean to rapidly avoid unfavorable environmental conditions and to amplify their population. Spores are produced sexually and asexually and their production is precisely controlled. Upstream developmental activators consist of fluffy genes have been known to orchestrate early induction of condiogenesis in a model filamentous fungus Aspergillus nidulans. To understand the molecular mechanisms underlying conidiogenesis in F. graminearum, we characterized functions of the F. graminearum fluffy gene homologs [2]. We found that FlbD is conserved regulatory function for conidiogenesis in both A. nidulans and F. graminearum among five fluffy gene homologs. flbD deletion abolished conidia and perithecia production, suggesting that FlbD have global roles in hyphal differentiation processes in F. graminearum. We further identified and functionally characterized the ortholog of AbaA, which is involved in differentiation from vegetative hyphae to conidia and known to be absent in F. graminearum [3]. Deletion of abaA did not affect vegetative growth, sexual development, or virulence, but conidium production was completely abolished and thin hyphae grew from abnormally shaped phialides in abaA deletion mutants. Overexpression of abaA resulted in pleiotropic defects such as impaired sexual and asexual development, retarded conidium germination, and reduced trichothecene production. AbaA localized to the nuclei of phialides and terminal cells of mature conidia. Successful interspecies complementation using A. nidulans AbaA and the conserved AbaA-WetA pathway demonstrated that the molecular mechanisms responsible for AbaA activity are conserved in F. graminearum as they are in A. nidulans. F. graminearum ortholog of Aspergillus nidulans wetA has been shown to be involved in conidiogenesis and conidium maturation [4]. Deletion of F. graminearum wetA did not alter mycelial growth, sexual development, or virulence, but the wetA deletion mutants produced longer conidia with fewer septa, and the conidia were sensitive to acute stresses, such as oxidative stress and heat stress. Furthermore, the survival rate of aged conidia from the F. graminearum wetA deletion mutants was reduced. The wetA deletion resulted in vigorous generation of single-celled conidia through autophagy-dependent microcycle conidiation, indicating that WetA functions to maintain conidia dormancy by suppressing microcycle conidiation in F. graminearum. In A. nidulans, FlbB physically interacts with FlbD and FlbE, and the resulting FlbB/FlbE and FlbB/FlbD complexes induce the expression of flbD and brlA, respectively. BrlA is an activator of the AbaA-WetA pathway. AbaA and WetA are required for phialide formation and conidia maturation, respectively [5]. In F. graminearum, the AbaA-WetA pathway is similar to that of A. nidulans, except a brlA ortholog does not exist. Amongst the fluffy genes, only fgflbD has a conserved role for regulation of the AbaA-WetA pathway.

• International Journal of Computer Science & Network Security
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• v.22 no.1
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• pp.288-294
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• 2022

This study aims to assess the knowledge of teachers working with students with autism spectrum disorder (ASD) regarding applied behaviour analysis (ABA). The study was concerned with teachers' knowledge of ABA, its application in the classroom, barriers to its use and desired training opportunities and/or resources to enhance teacher application of ABA strategies in the classroom. Data were collected via an online survey completed by 190 teachers with students diagnosed with ASD in British schools. The results revealed overall knowledge of ABA strategies for classrooms, with only some teachers uninformed about the broad use and some key elements, and general familiarity with skills crucial for applying ABA. Actual knowledge of ABA was found to be high. In terms of application of ABA, the majority of the teachers employed a wide range of known strategies. A number of barrier to the application of ABA were noted including a lack of knowledge and training, a lack of administrative support and a lack of time and physical resources. Theoretical knowledge is crucial for practical applications; however, practical training was found to be important to ensure intervention efficacy.

• Environmental Engineering Research
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• v.22 no.3
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• pp.231-236
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• 2017

Solid waste disposal and management is a critical problem in Nigeria. Annually, a huge quantity of municipal solid waste is generated in Aba. Municipal solid waste disposal in Aba poses severe challenge to environmental safety, public health and welfare of citizens. The situation is made worse by the indiscriminate dumping of refuse at roadsides, streets, waterways and empty lands. The impact of this waste management practice in Aba is environmental deterioration. Efforts to improve waste management in Aba have not recorded significant success. This paper therefore aims to highlight the challenges facing the waste management sector in Aba and proffer solutions on how to improve the sector.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.109-109
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• 2017

The core components of ABA-dependent gene expression signaling have been identified in Arabidopsis and rice. This signaling pathway consists of four major components; group A OsbZIPs, SAPKs, subclass A OsPP2Cs and OsPYL/RCARs in rice. These might be able to make thousands of combinations through interaction networks resulting in diverse signaling responses. We tried to characterize those gene functions using transient gene expression for rice protoplasts (TGERP) because it is instantaneous and convenient system. Firstly, in order to monitor the ABA signaling output, we developed reporter system named pRab16A-fLUC which consists of Rab16A promoter of rice and luciferase gene. It responses more rapidly and sensitively to ABA than pABRC3-fLUC that consists of ABRC3 of HVA1 promoter in TGERP. We screened the reporter responses for over-expression of each signaling components from group A OsbZIPs to OsPYL/RCARs with or without ABA in TGERP. OsbZIP46 induced reporter most strongly among OsbZIPs tested in the presence of ABA. SAPKs could activate the OsbZIP46 even in the ABA independence. Subclass A OsPP2C6 and -8 almost completely inhibited the OsbZIP46 activity in the different degree through the SAPK9. Lastly, OsPYL/RCAR2 and -5 rescued the OsbZIP46 activity in the presence of SAPK9 and OsPP2C6 dependent on ABA concentration and expression level. By using TGERP, we could characterize successfully the effects of ABA dependent gene expression signaling components in rice. In conclusion, TGERP represents very useful technology to study systemic functional genomics in rice or other monocots.

• Korean Journal of Medicinal Crop Science
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• v.12 no.6
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• pp.508-514
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• 2004

Chrysanthemum boreale M. is an important medicinal plant that has been historically used in herbal medicine and in the health food throughout East Asia. This study was conducted to investigate the influence of abscisic acid (ABA) and salicylic acid (SA) on plant growth, mineral content and effective components, such as essential oil, amino acid and cumambrin A, by means in order to increase the productivity and the quality of flowerheads in the plant. Yields of flowerheads were increased by 12.7%, 21.7% and 15.5% by ABA, SA and both treatments, respectively, as compared with the control. Inorganic nutrient content was changed by PGRs; SA treatment was increased by nitrogen, phosphorus and magnesium content but decreased by potassium of C. boreale M. flowerheads. Total content of amino acid was increased by SA but decreased by ABA treatment. Essential oil content and yields were increased to 9.7% and 33.8% by SA treatment. Moreover, the content of terpene, monoterpenoids and sesquiterpenoids, were improved by ABA treatment, especially, germacrene-D content was increased by 39.1%, as compared to control. In addition, yields of cumambrin A, sesquiterpene compound exhibiting blood-pressure activity, increased in all PGRs treatments, but its concentration in the C. boreale M. flowerheads only increased by ABA and both treatment. The experiment suggests that PGRs using ABA and SA could increase the yields and quality of C. boreale M. flowerheads.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.1
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• pp.25-34
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• 2018

This study was conducted to investigate the germination and proteome profile characteristics of wheat seeds treated under various concentrations of abscisic acid (ABA). After-ripening, the seeds of three wheat cultivars (Baegjoong, Keumkang, and Uri) showing different levels of dormancy were used. Germination index and germination rate of the cultivars was higher than 0.95% and 98%, respectively, and these were not significantly different under 0, 10, 30, and $50{\mu}M$ ABA at 7 d after germination. However, the growth of the shoot and radicle was significantly inhibited at 10, 30, and $50{\mu}M$ ABA compared to that at $0{\mu}M$ ABA. Mean ABA content of the embryos of seeds germinated at 0 and $50{\mu}M$ ABA for 7 d was 0.8 and $269.0ngmg^{-1}DW$, respectively. Proteins extracted from embryos germinated for 4 d were analyzed by two-dimensional gel electrophoresis, and proteins showing a difference of 1.5-fold or greater in their spot volume relative to that of $0{\mu}M$ ABA were identified. The expression of four protein spots increased at $50{\mu}M$ ABA and two protein spots were detected only at $50{\mu}M$ ABA; these six proteins were all identified as globulin types. Conversely, the expression of three protein spots decreased at $50{\mu}M$ ABA and were identified as cytosolic glutamine sysnthetase, isocitrate dehydrogenase, and S-adenosylmethionine synthetase 2. In conclusion, ABA did not inhibit the germination rate regardless of pre-harvest sprouting characteristics of the cultivars. However, the growth of the shoot and radicle was significantly inhibited by ABA, most likely through the down regulation of glutamine, methyl group donor, and polyamines biosynthesis, among others, while accompanied by globulin accumulation in the embryos.

• Journal of Life Science
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• v.15 no.2 s.69
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• pp.293-297
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• 2005

This experiment was carried to investigate the optimum concentration of abscisic acid (ABA) treatment for enhancing fruit coloration of 'Kyoho' grapes. Cluster and berry weights showed a tendency that increased in proportion to concentration of ABA treatment, but were not significant in all treatments. Also, soluble solids and titratable acidity were not significant during fruit development in all treatments. L-phenylalanine ammonia-lyase (PAL) activity showed a tendency that decreased after rapidly increased in all treatments, and was the highest in 1000 mg/l ABA treatment at final harvest. Anthocyanin and total phenolics contents were high in proportion to ABA treatment concentration, and anthocyanin content in 1000 mg/l ABA treatment was 2.5 folds of that in control. Fructose and glucose as soluble sugars were detected, but sucrose was not detected. Both fructose and glucose contents increased during fruit development, but showed little difference in all treatments.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.3
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• pp.174-185
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• 2002

This study was carried out to investigate the effects or abscisic acid (ABA), three concentrations, on growth, activities of antioxidant-related enzymes and grain yield of two rice plants (Oryza sativa L. cv. Hwamyungbyeo and cv. Namchunbyeo) exposed to ozone (0.150 ppm) for 6 hours a day for 30 days. The leaf chlorop0hyll contents, plant height, and tillering numbers were not shown significant difference. But ABA 10$^{-5}$ M treatment affects to growth slightly. In all concentrations of ABA, superoxide dismutase (SOB) activities were increased at tillering stage of Namchunbyeo which was exposed to ozone. It is considered that the optimum concentration of ABA is 10$^{-5}$ M for minimizing loss of grain yield loss.