• Title/Summary/Keyword: Agricultural R and D

Search Result 1,356, Processing Time 0.026 seconds

Growth, Photosynthesis and Zinc Elimination Capacity of a Sorghum-Sudangrass Hybrid under Zinc Stress (고농도 아연 조건에서 수수-수단그라스 교잡종의 생장, 광합성 및 아연 제거능)

  • Oh, Soonja;Koh, Seok Chan
    • Journal of Environmental Science International
    • /
    • v.25 no.8
    • /
    • pp.1143-1153
    • /
    • 2016
  • Plant biomass, photosystem II (PSII) photochemical activity, photosynthetic function, and zinc (Zn) accumulation were investigated in a sorghum-sudangrass hybrid (Sorghum bicolor ${\times}$ S. sudanense) exposed to various Zn concentrations to determine the elimination capacity of Zn from soils. Plant growth and biomass of the sorghum-sudangrass hybrid decreased with increasing Zn concentration. Symptoms of Zn toxicity, i.e., withering and discoloration of old leaves, were found at Zn concentrations over 800 ppm. PSII photochemical activity, as indicated by the values of $F_v/F_m$ and $F_v/F_o$, decreased significantly three days after exposure to Zn concentrations of 800 ppm or more. Photosynthetic $CO_2$ fixation rate (A) was high between Zn concentrations of 100-200 ppm ($22.5{\mu}mol$ $CO_2{\cdot}m^{-2}{\cdot}s^{-1}$), but it declined as Zn concentration increased. At Zn concentrations of 800 and 1600 ppm, A was 14.1 and $1.8{\mu}mol$ $CO_2{\cdot}m^{-2}{\cdot}s^{-1}$, respectively. The patterns of stomatal conductance ($g_s$), transpiration rate (E), and water use efficiency (WUE) were all similar to that of photosynthetic $CO_2$ fixation rate, except for dark respiration ($R_d$), which showed an opposite pattern. Zn was accumulated in both above- and below-ground parts of plants, but was more in the below-ground parts. Magnesium (Mg) and iron (Fe) concentrations were significantly low in the leaves of plants, and symptoms of Mg or Fe deficiency, such as a decrease in the SPAD value, were found when plants were treated with Zn concentrations above 800 ppm. These results suggest that the sorghum-sudangrass hybrid is able to accumulate Zn to high level in plant body and eliminate it with its rapid growth and high biomass yield.

Effect of Dietary Structural to Nonstructural Carbohydrate Ratio on Rumen Degradability and Digestibility of Fiber Fractions of Wheat Straw in Sheep

  • Tan, Z.-L.;Lu, D.-X.;Hu, M.;Niu, W.-Y.;Han, C.-Y.;Ren, X.-P.;Na, R.;Lin, S.-L.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.15 no.11
    • /
    • pp.1591-1598
    • /
    • 2002
  • The effect of different dietary structural carbohydrate (SC) to nonstructural carbohydrate (NSC) ratios on fiber degradation, digestion, flow, apparent digestibility and rumen fluid characteristics was studied with a design using 18 wethers fitted with permanent rumen and duodenum cannulae. All sheep were divided into six groups randomly, receiving six diets with varying SC to NSC ratios. All diets contained the same proportion of wheat straw and concentrate. The dietary SC to NSC ratios were adjusted by adding cornstarch to the concentrate supplements. The duodenal and fecal flows of dry matter (DM), neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicellulose (HC) and cellulose (CEL) were estimated using chromium-mordanted wheat straw as a flow marker. The degradation parameters of wheat straw DM, NDF, ADF, HC and CEL were determined by incubating the ground wheat straw in nylon bags in the rumen for different periods of time. There was no effect (p>0.05) of the different dietary SC to NSC ratios on rumen pH or $NH_3$-N, but acetate, propionate and butyrate concentrations were significantly affected (p<0.05 or p<0.01) by dietary SC to NSC ratios in the rumen fluid. When the dietary SC to NSC ratio was 2.86, the highest rumen degradability of wheat straw DM, NDF, ADF and CEL was found, but the highest apparent rumen digestibilities of DM, NDF, ADF, HC and CEL occurred at a 2.64 SC to NSC ratio. However, because of compensatory digestion in the hindgut, the apparent digestibilities of DM, NDF, ADF, HC and CEL were highest when the dietary SC to NSC ratio was 2.40. In conclusion, there is a optimal range of dietary SC to NSC ratios (between 2.86 and 2.40) that is beneficial to maximize wheat straw fiber degradation and apparent digestibility.

Relationship between Virulence and Cultural Characteristics in Calonectria ilicicola (Calonectria ilicicola의 병원성과 배양적 특성간의 상호관계)

  • Kim, K.D.;Russin, J.S.;Snow, J.P.;Valverde, R.A.
    • The Korean Journal of Mycology
    • /
    • v.26 no.3 s.86
    • /
    • pp.387-395
    • /
    • 1998
  • Mycelial growth, production of microsclerotia and perithecia, and presence of double-stranded RNA were examined in Calonectria ilicicola isolates from several hosts to detect morphological and/or genetic markers for comparison with levels of virulence. Variability in disease severity, production of microsclerotia and perithecia, and mycelial growth was observed across all isolates. None of 35 isolates of C. ilicicola examined contained detectable levels of double-stranded RNA. Disease severity on soybean cultivars correlated positively with production of both microsclerotia and perithecia. Mycelial growth correlated negatively with production of perithecia. Virulence on the cultivars and production of microsclerotia and perithecia were greater in isolates of C. ilicicola from soybean than those from peanut. These results suggest that the ability of isolates to produce microsclerotia and perithecia is a component of inoculum potential. Perithecia production may serve as a useful marker for characterizing virulence or host specialization in this homothallic fungus.

  • PDF

Distribution and Content of Geometric Isomers of Conjugated Linoleic Acid in Dairy Foods from the Quebec Province of Canada

  • Park, Seung-Yong;Ahn, Jae-Eun;Kim, Geun-Bae;Jung, Mun-Yhung;Lee, Byong-H.
    • Food Science and Biotechnology
    • /
    • v.17 no.1
    • /
    • pp.31-37
    • /
    • 2008
  • The distributions and content of geometrical isomers of conjugated linoleic acids (CLA) in dairy foods such as milk, yogurt, and cheese, produced or being sold in the Quebec province of Canada, were investigated by gas chromatographic analysis. The mean contents of total CLA (mg/g fat) were $5.06{\pm}0.74$ in 4 low-fat milk samples, $14.14{\pm}4.95$ in 6 yogurt samples, and $18.22{\pm}7.89$ in 5 natural ripened cheeses. Among the yogurt samples, YY contained the highest content of total CLA ($20.68{\pm}5.17\;mg/g$ fat). Among the cheese samples, Gruyere contained the highest amount of total CLA ($29.86{\pm}0.62$) as well as c-9,t-11 ($22.03{\pm}0.36\;mg/g$ fat), followed by Jarlsberg ($22.76{\pm}0.14$), Provolone ($16.42{\pm}0.52$), Cheddar ($13.83{\pm}0.81$), and Swiss ($8.23{\pm}1.11$). Based on the distribution ratios of CLA isomers in these dairy foods, the c-9,t-11 isomer appeared to be the major CLA isomer in both the low-fat milk ($89.87{\pm}2.39%$) and yogurt ($90.98{\pm}4.42%$). In the cheeses, however, the ratio of c-9,t-11 ($54.86{\pm}13.06%$) was slightly higher than that of c-10,c-12 ($40.81{\pm}13.40%$).

Determination of PID Coefficients for the Ascending and Descending System Using Proportional Valve of a Rice Transplanter

  • Siddique, Md. Abu Ayub;Kim, Wan-Soo;Baek, Seung-Yun;Kim, Yeon-Soo;Choi, Chang-Hyun;Kim, Yong-Joo;Park, Jin-Kam
    • Journal of Biosystems Engineering
    • /
    • v.43 no.4
    • /
    • pp.331-341
    • /
    • 2018
  • Purpose: This study was conducted to develop a linear Proportional-Integral-Derivative (PID) control algorithm for the ascending and descending system of a rice transplanter and to analyze its response characteristics. Methods: A hydraulic model using a single-acting actuator, proportional valve and a PID control algorithm were developed for the ascending and descending system. The PID coefficients are tuned using the Ziegler-Nichols (Z-N) method and the characteristics of unit step response are analyzed to select the PID coefficients at various pump speeds. Results: Results showed that the performance of the PID controller was superior in any condition. It was found that the highest settling time and maximum overshoot were less than 0.210 s and 5%, respectively at all pump speed. It was determined that the steady state errors were 0% in all the cases. The lowest overshoot and settling time were calculated to be nearly 2.56% and 0.205 s, respectively at the pump rated speed (2650 rpm). Conclusions: The results indicated that the developed PID control algorithm would be feasible for the ascending and descending system of a rice transplanter. Finally, it would be helpful to plant the seedlings uniformly and improve the performance of the rice transplanter.

Anti-inflammatory effect of Lycium barbarum on polarized human intestinal epithelial cells

  • Lee, So-Rok;Hwang, Hye-Jeong;Yoon, Ju-Gyeong;Bae, Eu-Young;Goo, Kyo-Suk;Cho, Sang-Joon;Cho, Jin Ah
    • Nutrition Research and Practice
    • /
    • v.13 no.2
    • /
    • pp.95-104
    • /
    • 2019
  • BACKGROUND/OBJECTIVES: Inflammatory Bowel Disease (IBD) has rapidly escalated in Asia (including Korea) due to increasing westernized diet patterns subsequent to industrialization. Factors associated with endoplasmic reticulum (ER) stress are demonstrated to be one of the major causes of IBD. This study was conducted to investigate the effect of Lycium barbarum (L. barbarum) on ER stress. MATERIALS/METHODS: Mouse embryonic fibroblast (MEF) cell line and polarized Caco-2 human intestinal epithelial cells were treated with crude extract of the L. chinense fruit (LF). Paracellular permeability was measured to examine the effect of tight junction (TJ) integrity. The regulatory pathways of ER stress were evaluated in MEF knockout (KO) cell lines by qPCR for interleukin (IL) 6, IL8 and XBP1 spliced form (XBP1s). Immunoglobulin binding protein (BiP), XBP1s and CCAAT/enhancer-binding homologous protein (CHOP) expressions were measured by RT-PCR. Scanning Ion Conductance Microscopy (SICM) at high resolution was applied to observe morphological changes after treatments. RESULTS: Exposure to LF extract strengthened the TJ, both in the presence and absence of inflammation. In polarized Caco-2 pretreated with LF, induction in the expression of proinflammatory marker IL8 was not significant, whereas ER stress marker XBP1s expression was significantly increased. In wild type (wt) MEF cells, IL6, CHOP and XBP1 spliced form were dose-dependently induced when exposed to $12.5-50{\mu}g/mL$ extract. However, absence of XBP1 or $IRE1{\alpha}$ in MEF cells abolished this effect. CONCLUSION: Results of this study show that LF treatment enhances the barrier function and reduces inflammation and ER stress in an $IRE1{\alpha}$-XBP1-dependent manner. These results suggest the preventive effect of LF on healthy intestine, and the possibility of reducing the degree of inflammatory symptoms in IBD patients.

Analysis of the PTO Driveline Rattle Noise on an Agricultural Tractor (농업용 트랙터 PTO 전동라인의 래틀 소음 분석)

  • Ahn, Da-Vin;Shin, In-Kyung;Han, Hyun-Woo;Son, Gwan-Hee;Park, Young-Jun
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.18 no.6
    • /
    • pp.45-54
    • /
    • 2019
  • In this study, we analyze the rattle noise of a power takeoff (PTO) driveline and develop a PTO driveline resonance model. We measured the rattle noise of the PTO driveline on the output shaft and, by analyzing the rattle noise in the time domain, we determine that the engine expansion stroke period matches the sound pressure of rattle noise. This finding helped us demonstrate that the rattle noise is caused by the collision between the PTO driving gear and the gear driven by the engine expansion stroke; the torsional vibration caused by this collision is affected by the angular velocity fluctuation of the PTO drive shaft. By measuring the angular velocity of the PTO drive shaft, we confirm that the angular velocity fluctuation of the engine flywheel tends to excessively amplify the PTO drive shaft angular velocity fluctuation. We conclude that the resonance, which occurs when the operating frequency of the engine is close to the natural frequency of the tractor power transmission system, causes the excessive angular velocity fluctuation of the PTO drive shaft. We performed a modal analysis of the PTO driveline resonance and, using the characteristic equation, we show that the resonance occurs when the engine rotation speed is close to 850 rpm, which matches the natural frequency of the PTO driveline.

Expression of Antioxidant Isoenzyme Genes in Rice under Salt Stress and Effects of Jasmonic Acid and ${\gamma}$-Radiation

  • Kim, Jin-Hong;Chung, Byung-Yeoup;Baek, Myung-Hwa;Wi, Seung-Gon;Yang, Dae-Hwa;Lee, Myung-Chul;Kim, Jae-Sung
    • Journal of Applied Biological Chemistry
    • /
    • v.48 no.1
    • /
    • pp.1-6
    • /
    • 2005
  • Analysis of chlorophyll (Chl) fluorescence implicated treatment of 40 mM NaCl decreased maximal photochemical efficiency of photosystem II (PSII) (Fv/Fm), actual quantum yield of PSII (${\Phi}_{PSII}$), and photochemical quenching (qP) in rice, but increased non-photochemical quenching (NPQ). Decreases in Fv/Fm, ${\Phi}_{PSII}$, and qP were significantly alleviated by $30\;{\mu}M$ jasmonic acid (JA), while NPQ increase was enhanced. Transcription levels of antioxidant isoenzyme genes were differentially modulated by NaCl treatment. Expression of cCuZn-SOD2 gene increased, while those of cAPXb, CATb, and CATc genes decreased. JA prevented salt-induced decrease of pCuZn-SOD gene expression, but caused greater decrease in mRNA levels of cAPXa and Chl_tAPX genes. Investigation of vacuolar $Na^+/H^+$ exchanger (NHX2) and 1-pyrroline-5-carboxylate synthetase (P5CS) gene expressions revealed transcription level of NHX2 gene was increased by JA, regardless of NaCl presence, while that of P5CS gene slightly increased only in co-presence of JA and NaCl. Unlike JA, ${\gamma}$-radiation rarely affected expressions of antioxidant isoenzyme, NHX2, and P5CS genes, except for increase in mRNA level of Chl_tAPX and decrease in that of pCuZn-SOD. These results demonstrate enhanced salt-tolerance in JA-treated rice seedlings may be partly due to high transcription levels of pCuZn-SOD, NHX2, and P5CS genes under salt stress.

Biological Resources Potential and the Recent State of International Cooperation in Indonesia

  • Park, Chang-Ho;Junaedi, Ahmad;Lee, Mi-Ra;Lee, Yeon-Hee
    • Interdisciplinary Bio Central
    • /
    • v.2 no.4
    • /
    • pp.11.1-11.8
    • /
    • 2010
  • Indonesia is a mega-biodiversity country having at least one trillion US Dollars value of biological resources per year over the next 20 years. Indonesia is home to 11 percent of the world's flowering plant species and 12 percent of all mammals. Many of Indonesia's species and more than half of the archipelago's endemic plant species are found nowhere else on the Earth. This information is just a small portion of all higher plants and animals being found in Indonesia. Former studies described that total number of species in Indonesia is estimated more than 1,000,000 and most of them remain unknown scientifically. Most of lower plants and animals have not been studied yet, so that greatest portion of Indonesia's biological resources has never been assessed with respect to its economic value or conservation status. Many developed countries are building cooperation with Indonesia on resources, mainly in the fields of grant aid, socio-economic services, R & D, researcher exchange, technology transfer, infrastructure, education/training, finance, etc. Indonesia will obtain greater benefits and management of its biological richness via increasing its international capacity to add value and information to its biological diversity. These goals can be achieved by close international collaboration on search of important biological resources and other bioactive products that have potential economic values. Development of biological resource-based technology stands as the industry of the $21^{st}$ century and, therefore, Indonesia has a unique opportunity to lead the process in the world.

Partial Characterization of Allelopathic Substances in Sorghum Stem by Different Organic Solvents and pH (수수 줄기에 함유(含有)된 타감물질(他感物質)의 용매(溶媒)와 pH에 따른 특성구명(特性究明))

  • Kim, S.Y.;De Datta, S.K.;Robles, R.P.;Kim, K.U.;Lee, S.C.;Shin, D.H.
    • Korean Journal of Weed Science
    • /
    • v.14 no.1
    • /
    • pp.42-48
    • /
    • 1994
  • The toxic compounds of sorghum stem extracts were isolated by different organic solvents and pH, and characterized and quantified in terms of their inhibition of seed germination and seedling growth in Echinochloa colona(L.) Link and radish(Raphanus sativus L.). Sequential partitioning of stem extract with various organic solvents with increasing polarity showed that all fractions of hexane, ethyl ether, methylene chloride, ethyl acetate, and the aqueous remainder inhibited germination and seedling growth in E. colona. Of the five fractions, the ethyl ether fraction had the greatest inhibitory effect on E. colona. Further separation of the ethyl ether fraction at different pH(pH 2-11) showed that phytotoxic compounds were acidic. The result indicates that the phytotoxin present in the stem extract may be nonpolar and acidic.

  • PDF