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Residue Dissipation Patterns of Indoxacarb and Pymetrozine in Broccoli under Greenhouse Conditions (시설재배 브로콜리 중 Indoxacarb 및 Pymetrozine의 잔류 소실특성)

  • Yang, Seung-Hyun;Lee, Jae-In;Choi, Hoon
    • Korean Journal of Environmental Agriculture
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    • v.39 no.1
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    • pp.75-82
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    • 2020
  • BACKGROUND: This study was carried out to establish pre-harvest residue limits (PHRLs) of indoxacarb and pymetrozine in broccoli under greenhouse conditions, based on dissipation patterns and biological half-lives of pesticides during 10 days after application. METHODS AND RESULTS: The field studies were conducted in two different greenhouse, located in Chungju-si (Field 1) and Gunsan-si (Field 2). Samples were collected at 0, 1, 2, 3, 5, 7 and 10 days after spraying pesticide suspension. The analytical methods for indoxacarb and pymetrozine using HPLC-DAD were validated by recoveries ranging of 94.3-105.4% and 81.8-96.0%, respectively, and MLOQ (Method Limit of Quantification) of 0.05 mg/kg. Biological half-lives of indoxacarb and pymetrozine were 2.9 and 3.2-3.8 days in broccoli, respectively. The lower 95% confidence intervals of dissipation rate constant of indoxacarb were determined as 0.1508 (Field 1) and 0.2017 (Field 2), whereas those of pymetrozine were calculated as 0.1489 (Field 1) and 0.1577 (Field 2). CONCLUSION: The significant differences were not observed between the dissipation rates of indoxacarb and pymetrozine in broccoli. The major factor affecting residue dissipation was the dilution effect by fast growth. The PHRLs for 10 days prior to harvest were recommended as 30.06 (Field 1) and 18.07 (Field 2) mg/kg for indoxacarb, and 4.84 (Field 1) and 4.43 (Field 2) mg/kg for pymetrozine, respectively.

Studies on the Production of (10-Deacetyl) Baccatin III in Cell Cultures of Taxus baccata Pendula (주목세포 배양에 의한 (10-Deacetyl) Baccatin III 생산 연구)

  • Yoo, Byoung-Sam;Moon, Won-Jong;Kim, Jean;Kim, Dong-Il;Byun, Sang-Yo
    • KSBB Journal
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    • v.13 no.2
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    • pp.174-180
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    • 1998
  • Enhanced production of (10-deacetyl) baccatin III and related taxanes was observed in suspension cultures of Taxus baccata Pendula. six % of initial glucose and sucrose concentration increased 10-deacetyl baccatin III production 3.5 and 2.5 times, respectively. Methyl jasmonate, as an elicitor, increased taxane production. Time course changes of taxane production after methyl jasmonate addition showed that baccatin II and 10-deacetyl baccatin III were detected first and paclitaxel, 10-deacetyl taxol and cephalomanine were produced in sequence. Feeding experiments with $500{\mu}M$ of benzoic acid increased 10-deacetyl baccatin III production 10 times. Baccatin III production was also increased 8 times by feeding of $500{\mu}M$ of lysine as a precursor.

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Growth Performance, Humoral Immune Response and Carcass Characteristics of Broiler Chickens Fed Alkali Processed Karanj Cake Incorporated Diet Supplemented with Methionine

  • Panda, K.;Sastry, V.R.B.;Mandal, A.B.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.5
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    • pp.677-681
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    • 2005
  • A study was conducted to see the effect of dietary incorporation of alkali (1.5% NaOH, w/w) processed solvent extracted karanj cake (SKC) supplemented with methionine on growth performance, humoral immune response and carcass characteristics of broiler chickens from 0 to 8 weeks of age. One hundred and twenty, day- old broiler chicks were wing banded, vaccinated against Marek' disease and distributed in a completely randomized design (CRD) into 3 groups of 40 chicks each, which was further replicated to 4 and fed on diet containing soybean meal and those of test groups were fed diets containing alkali (1.5% NaOH) treated SKC partially replacing soybean meal nitrogen of reference diet (12.5%) without or with supplementation of methionine (0.2%). Individual body weight of chicks and replicate-wise feed intakes were recorded at weekly intervals throughout the experimental period. Feed consumption from 1 to 14, 28, 42 and 56 d of age was recorded for each replicate and feed conversion efficiency (weight gain/feed intake) for the respective period was calculated. Mortality was monitored on daily basis. On 28$^{th}$ day of experimental feeding, two birds of each replicate in each dietary group (8 birds/diet) were inoculated with 0.1 ml of a 1.0% suspension of sheep red blood cells (SRBC) and the antibody titre (log 2) was measured after 5 days by the microtitre haemmagglutination procedure. After 42 days of experimental feeding, a retention study of 4 days (43-47 d) duration was conducted on all birds to determine the retention of various nutrients such as DM, N, Ca, P and GE. On 43$^{rd}$ day of experimental feeding, one representative bird from each replicate of a dietary treatment (4/dietary group) was sacrificed, after fasting for two hours with free access to water, through cervical dislocation to observe the weight of dressed carcass, primal cuts (breast, thigh, drumstick, back, neck and wing), giblet (liver, heart and gizzard), abdominal fat and digestive organs. The body weight gain of chicks fed reference diet and those fed diet incorporated with NaOH treated SKC (12.5% replacement) with or without methionine supplementation was comparable during 0 to 4 weeks of age. However, dietary incorporation of alkali processed SKC replacing 12.5% nitrogen moiety of soybean meal resulted in growth retardation, subsequently as evidenced by significantly (p<0.05) lowered body weight gain during 0 to 6 weeks of age in birds fed diet incorporated with alkali processed SKC at 6.43% without methionine as compared to those supplemented with methionine or reference diet. Dietary incorporation of alkali (1.5% NaOH) processed SKC replacing 12.5% of soybean meal nitrogen in the diet of broiler chickens had no adverse effect on feed conversion ratio during all the weeks of experimental feeding. The humoral immune response (HIR) as measured by the antibody titre in response to SRBC inoculation was comparable among all the dietary groups. No significant difference in the intake and retention of DM, N, Ca, P or GE was noted among the chicks fed reference and alkali processed SKC incorporated diets with or without methionine supplementation. None of the carcass traits varied significantly due to dietary variations, except the percent weight of liver and giblet. The percent liver weight was significantly (p<0.05) higher in the birds fed diet incorporated with alkali processed SKC as compared to that in other two groups. Thus solvent extracted karanj cake could be incorporated after alkali (1.5% NaOH, w/w) processing at an enhanced level of 6.43%, replacing 12.5% of soybean meal nitrogen, in the broiler diets up to 4 weeks of age, beyond which the observed growth depression on this diet could be alleviated by 0.2% methionine supplementation.

Evaluation and Assessment of Biosafety for Bacillus thuringiensis (Bt)-transgenic Rice: Responses of Daphnia magna Fed on Bt-transgenic Rice Variety (해충저항성 Bacillus thuringiensis (Bt) 벼의 환경위해성 평가: 해충저항성 Bt벼가 물벼룩(Daphnia magna)에 미치는 영향)

  • Oh, Sung-Dug;Shin, Hye-Chul;Sohn, Soo-In;Lee, Ki-Jong;Kim, Hyo-Jin;Ryu, Tae-Hun;Lee, Jang-Yong;Park, Beom-Seok;Kweon, Soon-Jong;Suh, Seok-Cheol;Park, Jong-Sug
    • Journal of Applied Biological Chemistry
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    • v.54 no.4
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    • pp.296-302
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    • 2011
  • Insect-resistant transgenic rice was developed by inserting the mCry1Ac1 a modified gene from the soil bacterium Bacillus thuringiensis (Bt). For biosafety assessment, we studied the effects on survival of cantor Daphnia magna, a commonly used as a model organism in ecotoxicological studies. D. magna fed on Bt rice and its near non-genetically modified (GM) counterparts (Nakdong) grown in the same environment (100% ground rice suspension). The Bt rice was comfirmed to have the insertion of T-DNA and protein expression by the polymerase chain reaction and ELISA analysis. Feeding study showed similar cumulative immobility and abnormal response of D. magna between Bt rice and non-GM counterparts. 48 h-$EC_{50}$ values of Bt rice and non-GM rice showed 4,429 and 2,889 mg/L respectively. The rice no observed effect concentration (NOEC) values for D. magna was suggested 1,000 mg/L. We conclude that the tested Bt-rice and Nakdong similar cumulative immobility for D. magna the widely used model organism. We found out that there is strong possibility that the growth of Bt rice didn't affect to non-target insects.

Preliminary Studies on Production of Porcine Leucocyte Interferon (돼지 Leucocyte Interferon 생산(生産)에 대한 기초연구(基礎硏究))

  • Jun, Moo Hyung;Chung, Un Ik;Park, Bong Kyun;Kim, Kyo Joon;Lee, Hun Jun
    • Korean Journal of Agricultural Science
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    • v.12 no.1
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    • pp.153-161
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    • 1985
  • As a preliminary step for production of large quantities of porcine leucocyte interferon(Por IFN-${\alha}$), various factors such as the sources of leucocytes, inducers and culture conditions were investigated. In addition, an assay system for the potency of porcine interferon was developed in a micro-system by using porcine kidney cell line, PK-15, and vesicular stomatitis virus. By the experiments, it was found that the porcine leucocyte interferon was synthesized more effectively in the leucocyte suspension with the higher viability and the lesser erythrocyte contamination. Regarding cell sources, the peripheral leucocytes produced a consistently higher unit of interferon than the spleen cells. When the efficiency of inducers was compared, the Sendai virus at the concentration of 125 HA unit/ml was found to be more effective for porcine leucocyte interferon production than the Newcastle disease virus. Average potency of 9 batches of the crude interferon measured by the established assay system was 1,200 unit/ml.

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Simple Mass-screening Methods for Resistance of Tomato to Fusarium oxysporum f. sp. lycopersici (토마토 시들음병에 대한 간편 대량 저항성 검정법)

  • Park, Myung Soo;Jang, Kyoung Soo;Choi, Yong Ho;Kim, Jin-Cheol;Choi, Gyung Ja
    • Horticultural Science & Technology
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    • v.31 no.1
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    • pp.110-116
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    • 2013
  • This study was carried out to establish the simple mass-screening methods for resistant tomato to Fusarium wilt caused by Fusarium oxysporum f. sp. lycopersici (FOL). Root dip inoculation method has been used in many studies on the resistance of tomato to disease. On the other hand, in mass-screening for resistant tomato to Fusarium wilt, the inoculation method is time-consuming and laborious procedure. Disease development of two FOL isolates on two cultivars of tomato according to inoculation method including root dip, tip and scalpel methods were investigated. In compatible interaction, tomato seedlings of each cultivar inoculated by tip method showed the lower and more variable disease severities than by root dip method. Whereas the seedlings by scalpel method represented clear resistant and susceptible responses to Fusarium wilt as root dip method. The resistance degree of each cultivar inoculated with FOL isolates by scalpel method was hardly affected by the tested incubation temperature and inoculum concentration. On the basis of the results, we suggest scalpel inoculation method as an efficient mass-screening method for resistant of tomato cultivars to Fusarium wilt. Roots of tomato seedlings at two-leaf stage grown in plastic cell tray were injured with scalpel and then spore suspension (more than $1{\times}10^7\;conidia{\cdot}mL^{-1}$) of FOL was poured directly on the roots. The infected plants were cultivated in a growth room at $25-30^{\circ}C$ for 4 weeks with 12-hours light a day.

Risk Assessment and Evaluation of Bt-transgenic Rice : Responses of Misgurnus anguillicaudatus and Cyprinus carpio fed on Bt-transgenic Rice Variety (해충저항성 Bt벼의 환경위해성 평가 : 해충저항성 Bt벼가 미꾸리(Misgurnus anguillicaudatus) 및 잉어(Cyprinus carpio)에 미치는 영향)

  • Oh, Sung-Dug;Lee, Dae-Yong;Sohn, Soo-In;Lee, Ki-Jong;Ryu, Tae-Hun;Lee, Jang-Yong;Park, Beom-Seok;Kweon, Soon-Jong;Suh, Seok-Cheol;Park, Jong-Sug
    • Journal of the Korean Society of International Agriculture
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    • v.23 no.5
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    • pp.570-577
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    • 2011
  • We developed insect-resistant GM rice(Bt transgenic rice) by inserting the mCry1Ac1 a modified gene from the soil bacterium, Bacillus thuringiensis. The Bt transgenic rice expressing the Bttoxin mCry1Ac1 was tested for the effects on survival of Misgurnus anguillicaudatus and Cyprinus carpio, commonly used as a model organism in ecotoxicological studies. M. anguillicaudatus and C. carpio fed 100% ground rice in suspension, using either Bt rice or non-GM counterpart rice(Nakdong). The Bt rice used for the test were confirmed to have the mCry1Ac1 gene expression by the immuno-strip and ELISA analysis. Feeding test showed that no significant differences in cumulative immobility and abnormal response of M. anguillicaudatus and C. carpio fed on between Bt rice and non-GM counterpart rice. The 96hr-LC50 values showed no difference between Bt rice(>1,000mg/L) and non-GM rice(>1,000mg/L). We concluded that there was no significant difference in toxicity for non-target organisms(M. anguillicaudatus and C. carpio) between Bt rice and non-GM counterparts.

Transport System of Specific Neutral Amino Acids in Suspension-Cultured Cells (현탁배양 세포내에서 특수 중성 아미노산의 수송)

  • Bong-Heuy CHO
    • Korean Journal of Plant Tissue Culture
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    • v.21 no.4
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    • pp.201-206
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    • 1994
  • The influx of glycine, valine, alanine, and histidine was inhibited by all tested neutral amino acids competitively and the reciprocal inhibitory studies showed the neutral amino acids possess the same transport system as neutral amino acids process to the same catalytic site of one carrier to each other, The molecules of histidine were transported actively as a neutral form through the neutral amino acid transport system but were not transported as a charged form. The Km values of the neutral amino acid transport system have been divided into three different category on basis of the affinity to the carrier, below 0.1mM, etween 0.1ImM-0.5mM and above 0.5mM. The $V_{max}$ was between $3.12{\mu}mole{\cdot}h^{-1}{\cdot}g$ fresh $weight^{-1}\;-\;15.1\;{\mu}mole{\cdot}h^{-1}{\cdot}g$ fresh $weight^{-1}$. Neutral amino acids cotransported with one $H^{+}per$ one molecule and one $K^{+}-efflux$ per one molecule for charge compensation. Histidine cotransported with proton per one molecule, however the movement of cotransported proton can't detectable because of the release of proton from the charged molecules of histidine in the medium.

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Selection of Brevibacillus brevis B23 and Bacillus stearothermophilus B42 as Biological Control Agents against Sclerotinia Rot of Lettuce (상추 균핵병 생물적방제를 위한 Brevibacillus brevis B23과 Bacillus stearothermophilus B42의 선발)

  • Hwang, Ji-Young;Shim, Chang-Ki;Ryu, Kyung-Yeol;Choi, Du-Hoe;Jee, Hyeong-Jin
    • Research in Plant Disease
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    • v.12 no.3
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    • pp.254-259
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    • 2006
  • Bacillus spp. isolated from mushroom medium wastes were evaluated for their biocontrol potentials on control of Sclerotinia rot of lettuce. The Bacillus isolates were more effectively obtained from waste suspension when directly added into nutrient agar(NA) medium than plating on the agar medium. Totally 42 isolates obtained from the wastes B23 and B42 showed highest antifungal activity against eight fungal pathogens such as Sclerotinia sclerotiorum, Rhizoctonia solani, Pythium ultimum, Phytophthora capsici, Fusarium oxysporum, Colletotrichum gloeosporioides, Cladosporium cucumerinum, and Botrytis cinerea and B23 and B42 were finally selected for further studies. Optimal concentration of the isolates was $10ml(10^7cfu/ml)$ to suppress the Sclerotinia rot of lettuce. Supplements such as starch, glycerol, and egg-yolk successfully maintained the bacterial population for 30 days in vitro and increased bio-control potentials against the disease. The bacterial isolate B23 alone showed 72% control value, furthermore it presented 95% control value when supplemented with 0.2% of starch, glycerol, and egg-yolk. The promising Bacillus isolates B23 and B42 were identified as Brevibacillus brevis and Bacillus stearothermophillus, respectively, based on morphological and physiological characteristics according to API database.

Studies on Polymer Chelates Binding with Metallic Ions (金屬이온結合性 高分子킬레이트에 關한 硏究)

  • Kyu Suck Choi;Sae Kun Shin;Kil Hyun Choi;Mun Kul Kim
    • Journal of the Korean Chemical Society
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    • v.21 no.1
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    • pp.60-66
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    • 1977
  • In the addition condensation reaction of m-phenylenediamine(MPD) and resorcinol (RES) with formaldehyde, the suspension polymerization in liquid paraffin was performed and the bead polymers were obtained with good results. The polymers were treated with dilute aqueous sodium hydroxide solutions in order to improve the adsorption capacity to the metallic ions and the adsorptivity to the several metallic ions, such as $Cd^{2+},\;Pb^{2+},\;Al^{3+},\;Mg^{2+},\;Co^{2+},\;and\;Hg^{2+}$ of the alkali-treated and untreated polymers were tested. These MPD-RES-F type resins showed better adsorption capacity to the heavy metallic ions such as $Cd^{2+}\;and\;Hg^{2+}$ than the light metallic ions such as $Pb^{2+},\;Al^{3+}\;and\;Mg^{2+}$, and the treatment of the resins with about 20 percent aqueous sodium hydroxide solution showed significant improvement of the adsorption capacity to the metallic ions in all cases.

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