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  • Title/Summary/Keyword: Agricultural R and D

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Evaluation of Glucose Dehydrogenase and Pyrroloquinoline Quinine (pqq) Mutagenesis that Renders Functional Inadequacies in Host Plants

  • Naveed, Muhammad;Sohail, Younas;Khalid, Nauman;Ahmed, Iftikhar;Mumtaz, Abdul Samad
    • Journal of Microbiology and Biotechnology
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    • v.25 no.8
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    • pp.1349-1360
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    • 2015
  • The rhizospheric zone abutting plant roots usually clutches a wealth of microbes. In the recent past, enormous genetic resources have been excavated with potential applications in host plant interaction and ancillary aspects. Two Pseudomonas strains were isolated and identified through 16S rRNA and rpoD sequence analyses as P. fluorescens QAU67 and P. putida QAU90. Initial biochemical characterization and their root-colonizing traits indicated their potential role in plant growth promotion. Such aerobic systems, involved in gluconic acid production and phosphate solubilization, essentially require the pyrroloquinoline quinine (PQQ)-dependent glucose dehydrogenase (GDH) in the genome. The PCR screening and amplification of GDH and PQQ and subsequent induction of mutagenesis characterized their possible role as antioxidants as well as in growth promotion, as probed in vitro in lettuce and in vivo in rice, bean, and tomato plants. The results showed significant differences (p ≤ 0.05) in parameters of plant height, fresh weight, and dry weight, etc., deciphering a clear and in fact complementary role of GDH and PQQ in plant growth promotion. Our study not only provides direct evidence of the in vivo role of GDH and PQQ in host plants but also reveals their functional inadequacy in the event of mutation at either of these loci.

Correlation Estimation between Geochemical Metal-fraction and Soil Properties in Agricultural and Industrial Soils (농경지 및 공장지역 토양 내 중금속 존재형태와 토양 특성과의 상관성 평가)

  • Lee, Hong-gil;Kim, Ji-in;Noh, Hoe-Jung;Park, Jeong-Eui;Kim, Tae Seung;Yoon, Jeong Ki
    • Journal of Soil and Groundwater Environment
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    • v.21 no.6
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    • pp.169-178
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    • 2016
  • The Standards, Measurement and Testing Programme (SM&T-formerly BCR) extraction procedure was applied to fractionate Cr, Cu, Ni, Pb and Zn in 23 top soil samples into: (i) exchangeable phase; (ii) reducible phase; (iii) oxidisable(sulfides and organics bound) phase; and (iv) residual phase. Fractions of Cr and Ni were in the order of residual > oxidisable > reducible > exchangeable phase. The oxidisable phase was identified as dominant for Cu and Pb. Zn had the highest ratio of exchangeable phase in comparision to the other metals. The bioavailability and mobility were assessed to be the greatest for Zn, followed by a decreasing order of Pb, Cu, Ni and Cr. All metal average concentrations in topsoil samples was higher in industrial sites than in agricultural sites. Our results revealed higher concentrations in topsoil samples (0~15 cm) than in sub soils (15~30 cm, 30~60 cm) for most metals at six sites (No. 5, 6, 17, 19, 20, 23). The fractions of exchangeable, reducible ad oxidisable phases showed relatively high correlation with soil pH, Fe/Mn oxide concentrations and organic matter contents, respectively.

Enhanced Production of Benzoylformate Reductase in Enterococcus faecalis under Oxidative Stress Established by Natural Electron Carriers

  • Baik, Sang-Ho;Cho, Pan-Ki;Kim, Mee-Hae;Yun, Sei-Eok
    • Journal of Microbiology and Biotechnology
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    • v.13 no.1
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    • pp.104-109
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    • 2003
  • Enhancement of the production of benzoylformate reductase (BFR) was attempted under oxidative stress established by natural electron carriers. -lipoic acid (LA), flavin adenine dinucleotide (FAD), and ubiquinone (UQ) did not inhibit growth of E. faecalis when their concentrations were as high as 10μM, while H2O2 and methyl viologen (MV2+) inhibited the bacterial growth. BFR activity in the bacterial extract had increased rapidly after 1 h of cultivation after the addition of 4μM of natural electron carriers, and the activity was maintained during further cultivation. BFR activity of the cells treated with the natural electron carriers was 40% higher than that of the control. In the presence of 4μMH2O2andMV2+, BFR activity increased, reaching the highest activity at about 5 h cultivation, and then decreased with further cultivation. It seems that natural electron carriers not only stimulate the induction of BFR, but also stabilize the enzyme. BFR was hardly affected by LA, FAD, and UQ, while H2O2andMV2+ inactivated the crude enzyme. The decrease of BFR activity in the presence of H2O2andMV2+ might be ascribed to inactivation of the enzyme by the oxidants.

The Characteristics of Flora and Distribution in Uiseong Traditional Irrigation System Reservoirs as National Important Agricultural Heritage System (국가중요농어업유산 의성 전통수리농업시스템 소류지의 식물상 및 분포 특성)

  • Cha, Doo-Won;Wei, Si-Yang;Lee, Jun-Young;Oh, Choong-Hyeon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.24 no.3
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    • pp.69-84
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    • 2021
  • This study was conducted as a basic data for the management of the Uiseong Traditional Irrigation Agricultural System by identifying plant diversity and distribution characteristics. The total number of plant taxa was identified as 88 families, 250 genera, 368 species, 7 subspecies, 9 varieties and 384 taxa. In the case of life form, the domancy form was in the therophytes(th), the radicoid form was a R5(monophyte), the disseminule form was the gravity D4(having no special modification for dissemination), and the growth form was the erect form was high. The number of plant taxa by land use type was higher in mountainoustype reservoirs and plain type reservoirs than other land use types. The distribution of plants by land use type according to the hemeroby grade was plantation in the case of 3 grade(meso-hemeroby) forests, and the understory were mainly photophilic plants. With 4 grade(β-euhemeroby), traditional cemetery, plain type reservoirs, mountainoustype reservoirs, stream, and rice terraces are areas with relatively low intensive management and have a wide variety of flora, whereas 5 grade(α-euhemeroby) orchard were mainly distributed with ruderal plant due to high intensive management. As for the number of plant taxa by reservoirs, the Wisgol pond in the case of plain type reservoirs, Ungok pond was high in mountainous type reservoirs. The protected species were rare plants 2 classification groups of Vulnerable(VU) species, 4 classification groups of Least Concrned(LC) species, 1 classification group of Data Deficient(DD) species, 5 classification groups of Korean endemic plants, and 49 classification groups of invasive alien plants, and the total naturalization index was 12.2%.

An Analysis of the Reinforced Concrete Circular Ring Sector Plates with Arbitrary Boundary Conditions (任意의 境界條件을 갖는 鐵筋콘크리트 扇形板의 解析(II) - 第 2報 鐵筋比 및 邊長比의 影響 -)

  • Jo, Jin-Gu
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.34 no.1
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    • pp.78-86
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    • 1992
  • This paper aims at investigating the effect of steel ratio and the magnitude of edge-ratio on the mechanical characteristics of reinforced concrete ring sector plate. The influence of steel bars was taken into account by coupling stiffness matrix of the steel bar element with that of the concrete plate element without dealing with separate element of steel bar and by establishing the composite stiffness matrix, which leads to the desirable result which does not increase th number of element could be obtained. Through case studies with 6 cases various steel ratios in ring sector plate supported at four edges and 4 cases with different open angles, the influence of the steel ratio was examined. A numerical analysis to find out the effect of the steel ratio d ue to above mentioned cases was carried out by 4 boundary conditions ; all edges clamped (B.C-1), all edges simply supported (B.C-2), curvilinear two edges clamped and other edges free (B.C-3) and curvilinear two edges simply supported and other edges free(B.C-4). The main results obtained are summarized as follows : 1. The effect of steel ratio on the magnitude of lateral deflection and x-directional bending moment at the center of sector plate and the midpoint of outer and inner curvilinear edges is almost the same up to 30 of open angle. Beyond 30 of the angle, the larger the angle, the greater the effect of ratio. 2. In design works using balanced steel ratio, the effect of steel bar can be ignored. But for larger open angles, especially greater than 90, it proves desirable to consider the effect of steel bar. 3. The effect of the arc length of center circle/straight edge on lateral deflection and bending moment is remarkable in B.C-2. For larger open angle, the effect is also noted except for B.C-3 which turn out hardly affected. 4. The effect of the radius of curvature/straight side length on lateral deflection and x-directional bending moment is noted in B.C-2. As open angle increases, B.C-1 and B.C-3 almost agree and B.C-2 approaches B.C-4.

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Development of a Path Generation and Tracking Algorithm for a Korean Auto-guidance Tillage Tractor

  • Han, Xiong-Zhe;Kim, Hak-Jin;Moon, Hee-Chang;Woo, Hoon-Je;Kim, Jung-Hun;Kim, Young-Joo
    • Journal of Biosystems Engineering
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    • v.38 no.1
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    • pp.1-8
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    • 2013
  • Purpose: Path planning and tracking algorithms applicable to various agricultural operations, such as tillage, planting, and spraying, are needed to generate steering angles for auto-guidance tractors to track a point ahead on the path. An optimal coverage path algorithm can enable a vehicle to effectively travel across a field by following a sequence of parallel paths with fixed spacing. This study proposes a path generation and tracking algorithm for an auto-guided Korean tractor with a tillage implement that generates a path with C-type turns and follows the generated path in a paddy field. A mathematical model was developed to generate a waypoint path for a tractor in a field. This waypoint path generation model was based on minimum tractor turning radius, waypoint intervals and LBOs (Limit of Boundary Offsets). At each location, the steering angle was calculated by comparing the waypoint angle and heading angle of the tractor. A path following program was developed with Labview-CVI to automatically read the waypoints and generate steering angles for the tractor to proceed to the next waypoint. A feasibility test of the developed program for real-time path tracking was performed with a mobile platform traveling on flat ground. The test results showed that the developed algorithm generated the desired path and steering angles with acceptable accuracy.

Nitrate enhances the secondary growth of storage roots in Panax ginseng

  • Kyoung Rok Geem ;Jaewook Kim ;Wonsil Bae ;Moo-Geun Jee ;Jin Yu ;Inbae Jang;Dong-Yun Lee ;Chang Pyo Hong ;Donghwan Shim;Hojin Ryu
    • Journal of Ginseng Research
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    • v.47 no.3
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    • pp.469-478
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    • 2023
  • Background: Nitrogen (N) is an essential macronutrient for plant growth and development. To support agricultural production and enhance crop yield, two major N sources, nitrate and ammonium, are applied as fertilizers to the soil. Although many studies have been conducted on N uptake and signal transduction, the molecular genetic mechanisms of N-mediated physiological roles, such as the secondary growth of storage roots, remain largely unknown. Methods: One-year-old P. ginseng seedlings treated with KNO3 were analyzed for the secondary growth of storage roots. The histological paraffin sections were subjected to bright and polarized light microscopic analysis. Genome-wide RNA-seq and network analysis were carried out to dissect the molecular mechanism of nitrate-mediated promotion of ginseng storage root thickening. Results: Here, we report the positive effects of nitrate on storage root secondary growth in Panax ginseng. Exogenous nitrate supply to ginseng seedlings significantly increased the root secondary growth. Histological analysis indicated that the enhancement of root secondary growth could be attributed to the increase in cambium stem cell activity and the subsequent differentiation of cambium-derived storage parenchymal cells. RNA-seq and gene set enrichment analysis (GSEA) revealed that the formation of a transcriptional network comprising auxin, brassinosteroid (BR)-, ethylene-, and jasmonic acid (JA)-related genes mainly contributed to the secondary growth of ginseng storage roots. In addition, increased proliferation of cambium stem cells by a N-rich source inhibited the accumulation of starch granules in storage parenchymal cells. Conclusion: Thus, through the integration of bioinformatic and histological tissue analyses, we demonstrate that nitrate assimilation and signaling pathways are integrated into key biological processes that promote the secondary growth of P. ginseng storage roots.

Evaluation of Physicochemical Deterioration and Lipid Oxidation of Beef Muscle Affected by Freeze-thaw Cycles

  • Rahman, M. H.;Hossain, M. M.;Rahman, S. M. E.;Amin, M. R.;Oh, Deog-Hwan
    • Food Science of Animal Resources
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    • v.35 no.6
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    • pp.772-782
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    • 2015
  • This study was performed to explore the deterioration of physicochemical quality of beef hind limb during frozen storage at −20℃, affected by repeated freeze-thaw cycles. The effects of three successive freeze-thaw cycles on beef hind limb were investigated comparing with unfrozen beef muscle for 80 d by keeping at −20±1℃. The freeze-thaw cycles were subjected to three thawing methods and carried out to select the best one on the basis of deterioration of physicochemical properties of beef. As the number of repeated freeze-thaw cycles increased, drip loss decreased and water holding capacity (WHC) increased (p<0.05) till two cycles and then decreased. Cooking loss increased in cycle one and three but decreased in cycle two. Moreover, drip loss, WHC and cooking loss affected (p<0.05) by thawing methods within the cycles. However, pH value decreased (p<0.05), but peroxide value (p<0.05), free fatty acids value (p<0.05) and TBARS value increased (p<0.05) significantly as the number of repeated freeze-thaw cycles increased. Moreover, significant (p<0.05) interactive effects were found among the thawing methods and repeated cycles. As a result, freeze-thaw cycles affected the physicochemical quality of beef muscle, causing the degradation of its quality.

Recent Progress in Transgenic Mouse Models as an Alternative Carcinogenicity Bioassay (형질전환 마우스 모델 발암성 평가의 최신 지견)

  • Son Woo-Chan;Kim Bae-Hwan;Jang Dong-Deuk;Kim Chull-Kyu;Han Beom-Seok;Kim Jong-Choon;Kang Boo-Hyon;Lee Je-Bong;Choi Yang-Kyu;Kim Hyoung-Chin
    • Toxicological Research
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    • v.21 no.1
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    • pp.1-14
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    • 2005
  • Transgenic mouse models have been introduced and accepted by regulatory bodies as an alternative to carcinogenicity assay models to predict and evaluate chemical carcinogens. The recent research outcomes in transgenic mouse models have made progressive advances in the understanding of chemical carcinogenesis and the evaluation of potential human carcinogens. However, these models still remain to be insufficient assay systems although the insufficiencies have been recognised and are being resolved. Based on up to date information from literature, this review article intends to understand currently accepted transgenic mouse models, issues arising from study design, interpretation of the study, results of validation project and their cancer prediction rate, and further perspectives of cancer assay models from the regulatory view point.

Studies on the Several Soil Factors Affecting on Alachlor and Paraquat Adsorption by Soils (Alachlor 와 Paraquat 의 토양흡착(土壤吸着)에 관여(關與)하는 토양인자(土壤因子)에 대한 연구(硏究))

  • Lim, Soo-Kil;Bong, Won-Ae
    • Korean Journal of Environmental Agriculture
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    • v.11 no.2
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    • pp.101-108
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    • 1992
  • In order to illustrate adsorption phenomena of herbicides(alachlor and paraquat) on soils, absorption equation of herbicides and the relationships between soil properties and adsorption constants were investigated with 22 soils. The results were as follows : 1. The shaking time for approaching equillibrium reaction of herbicides(alachlor and paraquat) with woils were about 30 minutes for paraquat and 4 hours for alachlor, respectively. 2. The distribution coefficients of alachlor were inbetween 0.81-33.83 in 5 ppm and 0.09-15.52 in 50 ppm, respectively. 3. The adsorption of alachlor was positively correlated with organic matter and paraquat was with clay content of soils. 4. Both paraquat and alachlor were highly adsorbed in Chunpo series soil containing low contents of organic matter and clay on account of different mechanism from other soils, 5. Freundlich's adsorption constant(K) was greater than distribution coefficient(Kd), and the differences between K and Kd's were to be increased with increasing equillibrium concentrations.

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