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  • Title/Summary/Keyword: Agricultural R and D

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Assessment of National Soil Loss and Potential Erosion Area using the Digital Detailed Soil Maps (수치 정밀토양도를 이용한 전국 토양 유실량의 평가 및 침식 위험지역의 분석)

  • Jung, Kang-Ho;Sonn, Yeon-Kyu;Hong, Seok-Young;Hur, Seung-Oh;Ha, Sang-Keon
    • Korean Journal of Soil Science and Fertilizer
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    • v.38 no.2
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    • pp.59-65
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    • 2005
  • This study was performed to estimate the soil loss on a national scale and grade regions with the potential risk of soil erosion. Universal soil loss equation (USLE) for rainfall and runoff erosivity factors (R), cover management factors (C) and support practice factors (P) and revised USLE for soil erodibility factors (K) and topographic factors (LS) were used. To estimate the soil loss, the whole nation was divided into 21,337 groups according to city county, soil phase and land use type. The R factors were high in the southern coast of Gyeongnam and Jeonnam and part of the western coast of Gyeonggi and low in the inland and eastern coast of Gyeongbuk. The K factors were higher in the regions located on the lower streams of rivers and the plain lands of the western coast of Chungnam and Jeonbuk. The average slope of upland areas in Pyeongchang-gun was the steepest of 30.1%. The foot-slope areas from the Taebaek Mountains to the Sobaek Mountains had steep uplands. Total soil loss of Korea was estimated as 50×106Mg in 2004. The potential risk of soil erosion in upland was the severest in Gyeongnam and the amount of soil erosion was the greatest in Jeonnam. The regions in which annual soil loss was estimated over 50Mgha1 were graded as "the very severe" and their acreage was 168×103ha in 2004. The soil erosion maps of city/county of Korea were made based on digital soil maps with 1:25,000 scale.

Relationship between Stress Gene Polymorphisms and Litter Size by AI in Pigs

  • Jin, H.J.;Kim, I.C.;Wee, M.S.;Yeon, S.H.;Kim, C.D.;Lee, S.S.;Cho, C.Y.;Cho, S.R.;Son, D.S.;Park, C.K.;Li, Z.D.
    • Journal of Embryo Transfer
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    • v.22 no.4
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    • pp.257-263
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    • 2007
  • This study was performed to investigate the relationship between PSS-HSP70 gene polymorphism and artificial insemination (AI) reproductivity in the pigs. The RFLP polymorphism of PSS and the SSCP polymorphisms of HSP70 K1, K3 and K4 PCR product were detected different patterns. In the experiment for AI of fresh semen, spring and fall season showed higher litter size born of 10.89 head than 10.47 head of summer season. Landrace was showed higher litter size of 9.96 head than that of Duroc and Yorkshire (p<0.05). Stress relating PSS and HSP70 polymorphism of PSS-Normal, HSP70 K1-BB, K3-AB, K4-AA showd a highest litter size born of 10.97 head and litter size born alive of 10.69 head than that of the other polymorphisms(p<0.05). In the experiment for AI of frozen semen, effects of season and pig breeds were not showed for litter size born. The stress relating polymorphism of PSS-Carrier, HSP70 K1-BB, K3-BB, K4-AB showed highest litter size born of 11.29 head and litter size born alive of 10.82 head and PSS-Normal, HSP70 K1-BB, K3-AB, K4-AA showed the lowest litter size born of 8.48 head and litter size born alive of 7.33 head than that of the other polymorphisms(p<0.05). These results suggest that AI litter size born for the stress of forzen thawed semen may be affected by PSS and HSP70 polymorphism in pigs.

Evaluation of Fermentation Ability of Microbes for Whole Crop Rice Silage Inoculant (총체 벼 사일리지용 미생물의 발효능력 평가)

  • Kim, Jong-Geun;Ham, Jun-Sang;Chung, Eui-Soo;Yoon, Sei-Hyung;Kim, Meing-Jung;Park, Hyung-Soo;Lim, Young-Chul;Seo, Sung
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.28 no.3
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    • pp.229-236
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    • 2008
  • This experiment was conducted to study on the evaluation of fermentation ability of microbes for whole crop rice silage Inoculant at National Institute of Animal Science, RDA from 2004 to 2005. We collected 28 strains of microbes from whole crop rice silage. According to acidity and growth ability, 5 strains of microbes was isolated (R4-1, R7-1, R7-2, R10-1, R12-1). The cultures of 4 strains were identified to be Lactobacillus plantarum (R4-1, R7-1, R7-2 and R10-1) and one was identified to be Lactobacillus pentosus (R12-1). Whole crop rice was harvested at the yellow ripen stage. It was ensiled in experimental silos (20ℓ capacity) with or without microbial additives (R4-1, R7-1, R7-2, R10-1, R12-1 and three commercial inoculant) and stored at room temperature for 60d. The pH value and acetic acid content of additivetreated silages were lower and lactic acid content was higher than those of the control (p<0.05). There was a trend for acetic acid content to be lowest and lactic acid to be highest in R7-1 treated silage. Crude protein (CP) contents of R7-2 treated silage was higher and acid detergent fiber (ADF) and neutral detergent fiber (NDF) contents of R7-1 treated silage was lower (p<0.05). Although some strains of inoculant could improve silage quality, L. plantarum R7-1 was more effective as an inoculant for whole crop rice silage. This microbe was named NLRI 401 and registered in the Korea Agricultural Culture Collection.

Improvement of Rotary Tine for Barley Seeder Attached to Rotary Tiller (로우터리 맥류파종기 경운날의 개량시험)

  • 김성래;김문규;김기대;허윤근
    • Journal of Biosystems Engineering
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    • v.4 no.1
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    • pp.1-23
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    • 1979
  • The use of barley seeder attached to rotary tiller in the rural area has a significant meaning not only for the solution of labor peak season, but also for the increase of land utilization efficiency. The facts that presently being used barley seeders are all based on the mechanical principles of the reverse rotation, center drive and are all using forward rotating tine, which is used to be easily and heavily worn out when it rotates reversely, raise problem of recommending them to rural area in Korea. Therefore, the main objective of the study was to develop new type of rotary tine attachable to barley seeders. To attain the objective the following approaches were applied. (1) The kinematic analysis of reverse rotating barley seeders. (2) The studies on the soil bin and artificial soil. (3) The comparative experiment on the power requirement of prototype tine. The results obtained from the studies are summarized as follow: 1. The kinematic analysis of barley seeder attached to rotary tiller: The following results were obtained from the kinematic analysis for deriving general formulae of the motion and velocity characterizing the rotary tine of barley seeders presently being used by farmers. a) The position vector (P) of edge point (P) in the rotary tine of reverse rotating, center drive was obtained by the following formula. P=(vt+Rcoswt)i+Rsinwtj+{Rcosθrsinαcos(wtβ+θr)+Rsinθrsinαsin(wtβ+θr)}lk b) The velocity of edge point (P^') of reverse rotating, center drive rotary tine was obtained by the following formula. (P^')=(V-wR sin wt)i+(w\cdot Rcoswt)j + \{ -w\cdot Rcos \theta r\cdot sin \alpha \cdot sin (wt-\beta +\theta r) + w\cdot Rsin \theta r\cdot  sin \alpha \cdot cos (wt- \beta + \theta r \} k c) In order to reduce the power requirement of rotary tine, the angle between holder and edge point was desired to be reduced. d) In order to reduce the power requirement, the edge point of rotary tine should be moved from the angle at the begining of cutting to center line of machine, and the additional cutting width should be also reduced. 2. The studies on the soil bin and artificial soil: In order to measure the power requirement of various cutting tines under the same physical condition of soil, the indoor experiments Viere conducted by filling soil bin with artificially made soil similar to the common paddy soil and the results were as follows: a) When the rolling frequencies(x) of the artificial soil were increased, the densIty(Y) was also increased as follows: y=1.073200+0.070780x0.002263x2(g/cm3) b) The absolute hardness (Y) of soil had following relationship with the rolling frequencies(x) and were increased as the rolling frequencies were increased. Y=37.740.64+0.17x0.0054x2(3.360.17x+0.0054x2)3(kg/cm3) c) The density of soil had significant effect on the cohesion and angle of internal friction of soil. For instance, the soil with density of 1.6 to 1.75 had equivalent density of sandy loam soil with 29.5% of natural soil moisture content. d) The coefficient of kinetiic friction of iron plate on artificial soil was 0.31 to 0.41 and was comparable with that of the natural soil. e) When the pulling speed of soil bin was the 2nd forward speed of power tiller, the rpm of driving shaft of rotary was similar to that of power tiller, soil bin apparatus is indicating the good indoor tester. 3. The comparative experiment on the power requirement of prototype tine of reverse rotating rotary: According to the preliminary test of rotary tine developed with various degrees of angle between holder and edge pcint due to the kinematic analysis, comparative test between prototype rotary tine with 30 and 10 of it and presently being used rotary tine was carried out 2nd the results were as follows: a) The total cutting torque was low when the angle between holder and edge point was reduced. b) θr (angle between holder and edge point) of rotary tine seemed to be one: of the factors maximizing the increase of torque. c) As the angle between holder and edge point (θr) of rotary tine was 30 rather than 45, the angle of rotation during cutting soil was reduced and the total cutting torque was accordingly reduced about 10%, and the reduction efficiency of total cutting torque was low when the angle between holder and edge point (θr) of rotary tine was 10, which indicates that the proper angle between holder and edge point of rotary tine should be larger than 10 and smaller than 30 . From above results, it could be concluded that the use of the prototype rotary tine which reduced the angle between holder and edge point to 30, insted of 45, is disirable not only decreasing the power requirements, but also increasing the durabie hour of it. Also forward researches are needed, WIlich determine the optimum tilted angle of rotary brocket, and rearrangement of the rotary tine on the rotary boss.

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Production of Rhizobium meliloti M14 Inoculum by Semi-continuous Cultivation (반연속식(半連續式) 배양(培養)에 의(依)한 Rhizobium meliloti M14의 균체생산(菌體生産))

  • Choi, Woo Young;Sohn, Jong Rok;Kim, Moon Kyu
    • Korean Journal of Agricultural Science
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    • v.11 no.2
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    • pp.322-327
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    • 1984
  • As a basic studies for the laboratory scale production of alfalfa inoculum, Rhizobium meliloti M14 was characterized for its carbon and nitrogen sources, and some parameters for broth cultivation in a chemostat were studied by semi-continuous operation. The result s obtained were as follows. 1. Growth rate of the strain was increased by disaccharides than by monosaccharides tested, and pentoses resulted in poor growth than hexoses. Sugar alcohols including inositol supported the best growth among sugars. 2. Mannitol in the yeast-mannitol-broth was substituted by natural carbon sources such as malt extract or molasses. 3. Ten per cent of fresh yeast water appeared to supply enough amount of growth factor s for the strain, and the effect was equivalent to 0.24 percent of the commercial yeast extract powder. 4. Batch growth of the stain in a chemostat, New Brunswick Micro Ferm 28L, reached in the early stationary growth phase of 57×109cells/ml after 36 hours of incubation. The culture at this stage was switched to semi-continuous cultivation, and the culture broth of four-fifth of the working volume was recovered every 24 hours when the maximal count was obtained.

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Genetic Diversity of Xanthomonas arboricola pv. pruni Isolated in Korea (우리나라에서 분리한 Xanthomonas arboricola pv. pruni의 유전적 다양성)

  • Park, So-Yeon;Lee, Young-Sun;Shin, Jong-Sub;Koh, Young-Jin;Jung, Jae-Sung
    • Journal of Life Science
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    • v.19 no.5
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    • pp.684-687
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    • 2009
  • Xanthomonas arboricola pv. pruni, the causal agent of bacterial shot holes in stone fruits, was known to have a low population diversity. To investigate the genetic characteristics of X. arboricola pv. pruni isolated in Korea, three strains which have identical 16S rDNA sequences - including type strain (LMG852), Japanese isolate (MAFF301420) and Korean isolate (XWD1) - were analysed based on the nucleotide sequences of three DNA regions and RAPD pattern. No sequence diversity among the three strains was found within the ITS, glnA and atpD gene sequences. However, five of 756 nucleotides of the atpD gene determined (accession number FJ429319) were different from those of the French strain available from the Genbank database. RAPD analyses performed with 40 different arbitrary primers revealed that two strains isolated from Korea and Japan showed similarity in their band patterns distinguished by type strain. These results suggest that Korean and Japanese strains are very close and belong to a population with a low genetic diversity, and might have a different origin from strains found in West Europe.

Effect of Continuous Cultivation Years on Soil Properties, Weed Occurrence, and Rice Yield in No-tillage Machine Transplanting and Direct Dry-seeding Culture of Rice (벼 무경운 기계이앙 및 건답직파 연속재배년수가 토양특성, 잡초발생 및 벼 생육에 미치는 영향)

  • Park, Hong-Kyu;Kim, Sang-Su;Choi, Won-Yong;Lee, Ki-Sang;Lee, Jae-Kil
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.47 no.3
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    • pp.167-173
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    • 2002
  • This experiment was conducted to figure out the change of soil physical properties, rice growth and yield with the years of continuous cultivation in direct dry-seeding and no-tillage machine transplanting. Experiments were conducted at NHAES(National Honam Agricultural Experiment Station, RDA, Iksan, Cheon Buk Province, South Korea) with a rice variety "Dongjinbyeo" from 1995 to 2000. In no-tillage machine transplanting cultivation, organic matter in soil was higher than that on direct dry-seeding and was significantly high in topsoil. Problematic weed species were E. crus-galli B., A. keisak H., and L. japonica M. Plant height and tiller number m-2 were higher in common-tillage during the total growth duration. The highest weedy rice occurrence of 27.5% was observed in live years' continuous direct dry-seeding and followed by 6.2%, in four years', and 3.7%, in three years'. The highest yield reduction of 38% was observed in five years' continuous direct dry-seeding. The reduction may resulted from the competition between weedy rice and cultivated rice.

Evaluation of Quality Characteristics of Korean and Chinese Frozen Chopped Garlic (국내산 및 중국산 냉동 다진 마늘의 품질 특성 평가)

  • Lee, Seul;Kim, Seokyoung;Hwang, Inguk;Yoo, Seonmi
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.1
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    • pp.111-117
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    • 2015
  • This study investigated quality characteristics of commercial frozen chopped garlic. We collected six kinds of commercial frozen chopped garlic, four of which were domestic and the remaining two made in China. The moisture contents and drip loss of domestic frozen chopped garlic were significantly lower than those of Chinese garlic. Drip loss was positively correlated with moisture content (r=0.918, P<0.01). Total pyruvate contents of frozen chopped garlic ranged from 118.69±5.97224.81±9.92μmol/g in domestic garlic and 75.27±5.9179.35±1.79μmol/g in Chinese garlic. Allicin contents of frozen chopped garlic ranged from 8.91±0.3413.09±0.35mg/g in domestic garlic and 5.91±0.086.05±0.27mg/g in Chinese garlic. Total thiosulfinate content of commercial frozen chopped garlic ranged from 0.60±0.071.33±0.12 optical density/g. Total thiosulfinate content of commercial frozen chopped garlic was positively correlated with allicin content (r=0.892, P<0.01). Flavor patterns of commercial frozen chopped garlic measured by an electronic nose showed no difference between domestic and Chinese garlics.

Isolation and Identification of Lipids from the Roots of Canna generalis (칸나(Canna generalis)의 뿌리로부터 지질화합물의 분리.동정)

  • Bang, Myun-Ho;Song, Myoung-Chong;Lee, Dae-Young;Yang, Hye-Jung;Han, Min-Woo;Baek, Nam-In;Lee, Youn-Hyung
    • Applied Biological Chemistry
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    • v.49 no.4
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    • pp.339-342
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    • 2006
  • Canna generalis was extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH and H2O, successively. from the EtOAc and n-BuOH fractions, four compounds were isolated through the repeated silica gel and ODS column chromatographies. From the results of physico-chemical data including NMR, MS and IR, the chemical structures of the compounds were determined as β-sitosterol(1), linoleic acid methyl ester(2),1-O-oleoyl-2-O-linoleoyl-3-O-β-D-galactopyranosyl-sn-glycerol(3), and daucosterol(4). They were the first to be isolated from Canna generalis.

Composition and Cytotoxicity of Essential Oil Extracted by Steam Distillation from Horseweed (Erigeron canadensis L.) in Korea (수증기 증류로 추출한 망초(Erigeron canadensis L.) 정유의 성분 분석과 독성 평가)

  • Choi, Hae-Jin;Wang, Hai-Ying;Kim, Young-Nam;Heo, Su-Jeong;Kim, Nam-Kyung;Jeong, Mi-Soon;Park, Yu-Hwa;Kim, Song-Mun
    • Applied Biological Chemistry
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    • v.51 no.1
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    • pp.55-59
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    • 2008
  • The composition of essential oil from the aerial part of Erigeron canadensis L. was analyzed by GC-MS. Thirty-one constituents were identified from the essential oil: eighteen hydrocarbons (91.99% of the total oil), two acetates (2.92%), three alcohols (3.59%), four ethers (0.49%), one aldehyde (0.05%), and three ketone (0.23%). Major constituents of the essential oil were D,L-limonene (68.25% of the total oil) and delta-3-carene (15.9%). The IC50 value of the essential oil was 0.027 μg mg1 in MTT assay using HaCaT keratinocyte cell line.