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Toxicity Evaluation of 'Bt-Plus' on Parasitoid and Predatory Natural Enemies (기생성 및 포식성 천적에 대한 작물보호제 '비티플러스'의 독성 평가)

  • Seo, Sam-Yeol;Srikanth, Koigoora;Kwon, Gi-Myon;Jang, Sin-Ae;Kim, Yong-Gyun
    • Korean journal of applied entomology
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    • v.51 no.1
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    • pp.47-58
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    • 2012
  • Effect of a new crop protectant 'Bt-Plus' on natural enemies was analyzed in this study. Tested natural enemies included two parasitic species of $Aphidius$ $colemani$ and $Eretmocerus$ $eremicus$, and four predatory species of $Harmonia$ $axyridis$, $Orius$ $laevigatus$, $Amblyseius$ $swirskii$, and $Phytoseiulus$ $persimilis$. 'Bt-Plus' was formulated by combination of three entomopathogenic bacteria ($Xenorhabdus$ $nematophila$ (Xn), $Photorhabdus$ $temperata$ subsp. $temperata$ (Ptt), $Bacillus$ $thuringiensis$ (Bt)) and bacterial metabolite (BM). All three types of 'Bt-Plus' showed significantly higher toxicities against fourth instar $Plutella$ $xylostella$ larvae than Bt single treatment. Two types of bacterial mixtures ('Xn+Bt' and 'Ptt+Bt') showed little toxicity to all natural enemies in both contact and oral feeding assays. However, 'BM+Bt' showed significant toxicities especially to two predatory mites of $A.$ $swirskii$ and $P.$ $persimilis$. The acaricidal effects of different bacterial metabolites were evaluated against two spotted spider mite, $Tetranychus$ $urticae$. All six BM chemicals showed significant acaricidal effects. The BM mixture used to prepare 'Bt-Plus' showed a high acaricidal activity with a median lethal concentration at 218.7 ppm (95% confidence interval: 163.2 - 262.3). These toxic effects of bacterial metabolites were also proved by cytotoxicity test against Sf9 cells. Especially, benzylideneacetone, which was used as a main ingredient of 'BM+Bt', showed high cytotoxicity at its low micromolar concentration.

Parameterization of the Temperature-Dependent Development of Panonychus citri (McGregor) (Acari: Tetranychidae) and a Matrix Model for Population Projection (귤응애 온도발육 매개변수 추정 및 개체군 추정 행렬모형)

  • Yang, Jin-Young;Choi, Kyung-San;Kim, Dong-Soon
    • Korean journal of applied entomology
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    • v.50 no.3
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    • pp.235-245
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    • 2011
  • Temperature-related parameters of Panonychus citri (McGregor) (Acarina: Tetranychidae) development were estimated and a stage-structured matrix model was developed. The lower threshold temperatures were estimated as $8.4^{\circ}C$ for eggs, $9.9^{\circ}C$ for larvae, $9.2^{\circ}C$ for protonymphs, and $10.9^{\circ}C$ for deutonymphs. Thermal constants were 113.6, 29.1, 29.8, and 33.4 degree days for eggs, larvae, protonymphs, and deutonymphs, respectively. Non-linear development models were established for each stage of P. citri. In addition, temperature-dependent total fecundity, age-specific oviposition rate, and age-specific survival rate models were developed for the construction of an oviposition model. P. citri age was categorized into five stages to construct a matrix model: eggs, larvae, protonymphs, deutonymphs and adults. For the elements in the projection matrix, transition probabilities from an age class to the next age class or the probabilities of remaining in an age class were obtained from development rate function of each stage (age classes). Also, the fecundity coefficients of adult population were expressed as the products of adult longevity completion rate (1/longevity) by temperature-dependent total fecundity. To evaluate the predictability of the matrix model, model outputs were compared with actual field data in a cool early season and hot mid to late season in 2004. The model outputs closely matched the actual field patterns within 30 d after the model was run in both the early and mid to late seasons. Therefore, the developed matrix model can be used to estimate the population density of P. citri for a period of 30 d in citrus orchards.

The Study of Environmental Risk Assessment for Fluorescent Genetically Modified Silkworms (형광단백질 발현 유전자변형 누에(Bombyx mori )의 환경위해성 평가연구)

  • Kim, Hyunjung;Jung, Chuleui;Goo, Taewon;Yi, Hoonbok
    • Korean journal of applied entomology
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    • v.53 no.3
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    • pp.199-207
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    • 2014
  • It is true that the proper environmental risk assessments for many GM (Genetically Modified) insects almost have not been executed in Korea. Therefore, we tested the environmental risk assessment about GM silkworms if there is any difference between GM silkworms and non-GM silkworms by the following three measurements. First, we measured their mobility in the breeding environment conditions with food and without food. Secondly, we measured their viability at the artificial extreme environmental conditions (low and high temperature and humidity, absent/present of foods,) after escaping from their breeding environments. Thirdly, we observed the number of laying eggs and their hatchability between GM silkworms and non-GM silkworms with four different pair experiments. The mobility of GM silkworms and non-GM silkworms statistically did not differ, and the egg productivity and hatchability were not also different. The hatchability by couple of GM female silkworms and non-GM male silkworms was lower than by non-GM male and female couple between the GM silkworms and non-GM silkworms, and there was statistically different. Relatively, the viability of GM silkworms was lower than non-GM silkworms. We could not exactly test for viability of silkworms in low temperature conditions because of their hibernating. Although there was any difference in viability and hatchability between GM silkworms and non-GM silkworms, all ability of GM silkworms was lower than non-GM silkworms. Conclusively, the environmental risk of GM silkworm was relatively lower than non-GM silkworm in this study.

Establishment of Optimal Rearing Conditions for the Production of Tenebrio molitor Larvae (갈색거저리 유충 생산을 위한 효율적인 사육조건 확립)

  • Kim, Sihyeon;Kim, Jong Cheol;Lee, Se Jin;Kim, Jae Su
    • Korean journal of applied entomology
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    • v.55 no.4
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    • pp.421-429
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    • 2016
  • Tenebrio molitor larvae contain large amounts of proteins, lipids and other functional materials, enabling this insect to be used as an edible food source in animal feeds and for industrialization. Although many efforts have been made to set up mass rearing systems, few studies have been conducted to establish optimal rearing conditions for the production of high quality T. molitor larvae. Herein we investigated 1) the effects of additional diets on the survival and fecundity of the insect, 2) the relationship between oviposition period and the uniformity of larval size, 3) the effects of rearing density and temperature on insect development, and 4) the storage stability of eggs and pupae at low temperatures given possible temporary production discontinuation. The addition of carrot and zucchini to the traditional wheat bran diet significantly increased the survival and fecundity rate of adult T. molitor. Of the three different oviposition sampling periods (3, 7, and 14 days) used to investigate the uniformity of the hatched larvae in each treatment, the period of 3 and 7 days provided higher uniformity than the 14 days oviposition period. Larval development was faster at $30^{\circ}C$ than at 20, 25, and $35^{\circ}C$. Interestingly, oviposition rates were highest at $20^{\circ}C$ but showed much slower larval development and lower uniformity at $30^{\circ}C$. Regarding the effect of larval rearing densities (1, 10, 20, 30, 40, and 50 larvae per 90 mm diam. dish), larval weight was significantly reduced at higher rearing densities, but larval longevity and length were not influenced by rearing density. The 30 larvae/dish is suggested to be a reasonable density to be applied to mass production systems. When kept at $4^{\circ}C$, T. molitor eggs showed a significant reduction in hatching rate; however, when stored under the same conditions, pupae emergence rates remained high until 10 weeks, suggesting that storage at low temperatures is more suitable for the pupal stage than the egg stage. Our findings suggest that an increase in T. molitor adult survival and fecundity rates and a uniformity of hatched larval development can be achieved with the following recommendations: a combination diet (including wheat bran), a 7-day oviposition period; a larvae-rearing temperature of $30^{\circ}C$, a rearing density of 30 larvae/dish, and the storage of pupal stages at low temperatures in the case of rearing discontinuation. This study serves as a strong foundation for the successful mass production of high quality T. molitor larvae.

Species Identification of Noctuid Potential Pests of Soybean and Maize, and Estimation of Their Annual Adult Emergence in Suwon, Korea (수원지방에서 콩과 옥수수 가해 밤나방과의 잠재해충에 대한 종 동정과 연중 성충 발생 추정)

  • Jung, Jin Kyo;Kim, Eun Young;Kim, I Hyeon;Seo, Bo Yoon
    • Korean journal of applied entomology
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    • v.59 no.2
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    • pp.93-107
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    • 2020
  • Adults of seven noctuid potential pests (Spodoptera frugiperda, S. litura, S. exigua, Ctenoplusia agnata, Mythimna loreyi, Athetis dissimilis, and A. lepigone) of soybean and maize in Suwon, Korea were identified by their morphological characteristics in the wing pattern and male genitalia and partial mitochondrial DNA sequences of cytochrome c oxidase subunit 1 gene. The generation number of adults that emerge annually in six species (except A. lepigone) was estimated from the data on density fluctuations of adults caught in sex pheromone traps in 2019 and the forecasted data using temperature-associated development and reproduction models for those species. S. frugiperda adults were caught from July 27th to October 31st in 2019, and hence were initially estimated to emerge three times per year. But, it was finally expected that S. frugiperda adults could possibly emerge a total of four times per year in Suwon, considering larval emergence observed during mid- and late June in other areas. Adult emergence of S. litura, S. exigua, C. agnata, and M. loreyi in 2019 was observed from May 29th to November 6th, from May 14th to November 6th, from May 26th to October 25th, and from May 31st to November 23rd, respectively. Annual adult emergence of these four species was estimated as at least four times. Adults of A. dissimilis were caught from May 26th to September 11th in 2019, and adult emergence was estimated at only twice per annum. It was postulated that the first adult populations of five species except the two Athetis species were probably migrated from other areas.

Serum cholinesterase activities and serum bromide concentrations in farmers (농업인에서의 체내 잔류농약 검출)

  • Choi, Soo-Jin;Hwang, Sang-Hyun;Chun, Sa-Il;Min, Won-Ki;Lee, Seon-Ho;Kim, Sung-Ryul;Kim, Young-Sik;SunWoo, Sung;Jun, Tae-Hee;Chung, Tae-Heum
    • Journal of agricultural medicine and community health
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    • v.23 no.2
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    • pp.305-310
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    • 1998
  • The usage or agricultural chemicals is on the increasing tendency. Methyl bromide and organophosphate are the most widely used toxic agricultural chemicals in Korea. We try to set up the methods to detect the accumulation of these chemicals in Korean farmers. Blood samples were collected for 121 farmers of slack's season in February 1998. And survey about arable acreage and usage of the gloves and masks was also performed. Serum cholinesterase activities and bromide concentrations were measured with gold chloride method and colorimetric method. The reference ranges of serum cholinesterase activity and bromide concentration were 1.6~15.9 U/mL and below $72.9{\mu}g/mL$. Serum bromide concentrations of farmers and normal controls showed no differences. Serum cholinesterase activities of farmers were significantly higher than those of normal controls. According to the arable acreages and usage of the gloves and masks, serum bromide concentrations and cholinesterase activities showed no differences. In conclusion, serum cholinesterase activities and bromide concentrations showed no differences between farmers of slack's season and normal controls.

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Effects of Dropwort Powder on the Quality of Castella (미나리가루의 첨가가 Castella의 품질에 미치는 영향)

  • Park, Sang-Jun;Lee, Kwang-Suck;An, Bye-Lyung
    • Journal of the East Asian Society of Dietary Life
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    • v.17 no.6
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    • pp.834-839
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    • 2007
  • This study was designed to determine the optimal ratio of dropwort powder in castella by adding the powder at levels of 0, 3, 6, 9, and 12% respectively. The properties of the castella were analyzed by specific gravity, specific volume, color determinations, texture properties and sensory evaluation. The Specific gravity increased with increasing amount of dropwort powder. However, the specific volume decreased with increasing dropwort powder. For the color values, as more dropwort powder was added, the L-value decreased. The castella with 9% dropwort powder had a higher hardness, gumminess, and chewiness. A sensory panel perceived that the external and internal color of the castella become darker with the dropwort powder substitution and the grain size decreased with increasing amount dropwort powder, while sweet taste showed no significant difference. The order of overall preference was DP 9>DP 6>DP 12>CON>DP 3. Therefore, the substitution of 9% of wheat flour with dropwort powder was recommended in the production of castella.

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A Study on the Effect of Luffae Fructus Retinervus Herbal-Acupuncture at ST36 on Collagen-induced Arthritis in Mice (족삼리(足三里) 사과락약침(絲瓜絡藥鍼)이 생쥐의 Collagen-induccd Arthritis에 미치는 영향)

  • Chae, Choong-heon;Choi, Sun-mi;Yim, Yun-kyoung
    • Journal of Acupuncture Research
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    • v.22 no.1
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    • pp.131-144
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    • 2005
  • Objective : The aim of this study is to observe the effect of Herbal-acupuncture(HA) with Luffae Fructus Retinervus Herbal-Acupuncture Solution(LFR-HAS) at ST36(Joksamni) on Collagen Ⅱ -induced arthritis(CIA) in mice. Methods : DBA1/J mice were immunized with bovine type Ⅱ collagen(CⅡ) on days 0 and 21 to induce an arthritis. The mice were divided into 5 groups. They were Normal group(wild type), Control group(CIA), Saline group(CIA +saline injection), Needle Prick group(CIA +single Prick with an injection needle) and LFR-HA group(CIA +LFR-HA treatment). The saline injection, needle prick and LFR-HA were made on the right ST36(Joksamni) of mice for 5 weeks, 3 times a week beginning 4 weeks after the booster immunization. Results : 1. The highest synovial rate of lung fibroblasts was measured in the 1% LFR-HAS. 2. TNF-${\alpha}$ expression of survival cells from CIA mouse joint was significantly reduced in the 1% LFR-HAS. 3. The incidence of arthritis and the spleen weight of CIA mouse were significantly reduced by the Luffae Fructus Retinervus Herbal-Acupuncture (LFR-HA) at ST36. 4. The concentrations of IL-6, INF-${\alpha}$, INF-${\alpha}$, IgG, IgM, and anti-collagen Ⅱ in the CIA mouse serum were significantly reduced by the LFR-HA at ST36. 5. The histological examination showed that, in the LFR-HA group, the cartilage destruction and the synoviocyte proliferation in the CIA mouse joint were not significant compared to the control group, and the collagen fiber was similarly expressed as the normal group. 6. In the LFR-HA group, the ratio of CD3e+ to CD19+ cell, and the ratio of CD4+ to CD8+ cell in the lymph node were similarly maintained as those of the normal group. 7. CD69+/CD3e+ and CD11a+/CD19+ cells in the CIA mouse lymph node were significantly reduced by the LFR-HA at ST36. 8. CD11b+/Gr-1+ cells in the CIA mouse joint were significantly reduced by the LFR-HA at ST36. Conclusions : These results indicate that Luffae Fructus Retinervus Herbal-Acupuncture (LFR-HA) at ST36 may regulate the immune system and have a therapeutic effect on Collagen-induced arthritis(CIA) in mice.

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제15회 산란계 경제능력 검정 성적

  • 국립종축장;대한양계협회
    • KOREAN POULTRY JOURNAL
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    • v.13 s.146
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    • pp.108-116
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    • 1981
  • 제15회 산란계 경제능력검정에는 총 13개 계군이 출품되었으며 능력검정 결과를 요약하면 다음과 같다. 1. 육추율, 육성율, 성계생존율 이번회 검정계의 육추율은 13개 계군 평균 97.72$\%$로서 14회 99.7$\%$와 비슷하다. 특히 이번 검정에서 육추기간 중 한마리의 폐사도 없는 구는 3구였으며 9구 만이 79.64$\%$로 육추율이 가장 낮았는데 그 원인은 1개 검정소에서 육추기간 중 백혈병으로 인한 폐사수가 많았기 때문으로 보인다. 육성율 평균은 99.07$\%$로서 14회 99.0$\%$와 같았고 한마리의 폐사도 없는 구는 11구로서 최고 육성율을 보였다. 성계 생존율은 평균이 90.14$\%$로서 14회의 92.6$\%$에 비슷 하였으며 13구는 97.98$\%$로서 상당히 좋은 성적을 보였으며 6구, 7구 9구, 10구 및 11구는 90$\%$이하로 성계생존율은 5회 점검 이후 점차 높아 졌는데 이유는 MD백신이 개발되어 이의 접종으로 인한 마렉병의 발생을 예방 할 수 있었던 것으로 생각된다. 2. 성 성숙일령 15회 검정에서 13개 계군의 평균 성 성숙 일령은 163일에서 14회 161일과는 비슷하였는데 성 성숙 일령은 육성기의 사료 급여와 사양관리에 따라서 영향을 많이 받는 형질이므로 더 이상의 고찰이 필요하지 않다. 성 성숙이 제일 빠른구는 5구의 154일이었고 늦은 구는 9구의 168일 이었는데 그 차는 14일이였다. 3. 산란율 및 산란지수 이번 검정계군의 평균 산란율은 70.14$\%$로서 14회에 73.8$\%$와 약 3.6$\%$가 낮았다. 한편 최고 산란율을 나타낸 구는 5구의 73.86$\%$였으며 산란율이 제일 낮은 구는 11구의 65.95$\%$였다. 산란지수의 평균은 232.02로서 14회의 246.5보다는 14.5개가 적었는데 이는 산란율에서와 같은 경향치 였다. 최고 산란 지수를 보인 구는 5구의 250.69였고 2구와 3구, 8구, 13구도 240이상으로서 상당이 좋은 성적을 보였으며 9구는 204.82로서 산란지수가 최하위 였고 최상위와 최하위와의 산란지수의 차이는 무려 45.87이었다. 4. 사료 요구율 13개 계군의 평균사료 요구율은 2.67로서 14회 2.68과 비슷하였다. 사료 요구율이 제일 낮았던구는 3구의 2.56이였고 사료 요구율이 제일 높았던 구는 9구의 2.78이였다. 5. 난중 13개 계군의 평균난중은 60.72g으로서 14회 59.08g보다는 약간 무거웠는데 난중은 다른 형질에 비하여 유전력이 높은 형질인 것을 감안할 때 사양관리 면에서의 영향이 아니고 출품계군의 구성에 의한 영향인 것으로 생각된다. 8회 검정 성적 중 난중이 제일 무거운 구는 4구의 63.32g이었고 제일 가벼운 구는 5구의 58.08g이었다. 6. 체중 300일령 평균체중은 1,966.33.g으로 14회 1,986.7g보다는 가벼웠는데 체중 역시 유전력이 높은 형질로서 이 차이는 검정계군의 구성에 따른 차이로 생각 된다. 500일령 체중의 평균은 1,985.68g으로 14회의 1,994.9g보다는 약간 가벼웠으나 500일령 체중에 있어서와 같이 검정계군의 구성에 따른 차이로 생각 된다. 7. 사료 섭취량 육추기간 중의 1일 1수당 평균사료 섭취량은 32.97g으로 14회 34.82g보다 적었는데 이것 역시 출품계군의 구성에 있어 겸용종 내지 유색종의 비율이 낮았던 데에 기인한 것으로 생각된다. 육성기의 1일 1수당 사료섭취량은 70.06g으로서 14회의 70.91g과 같았고 산란기간 중의 1일 1수당 사료섭취량은 평균이 113,54g으로서 14회 115.81g과 비교할 때 큰 차가 없었으며 특히 11구는 118.61g으로 가장 사료를 많이 섭취 했는데 산란기 수당 사료 섭취량은 해가 거듭될수록 적어지는 경향이었다. 8. 경제성 13개 검정계군이 총 수입은 45,405원으로 계란 판매 수입은 86.4$\%$였고 폐계 판매수입은 13.59$\%$였으며 총 지출은 33,657원으로 사료비의 지출비율이 95.5$\%$였고 초생추대가 4.5$\%$였다.

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Effects of combined argon gas treatment on the quality of fresh-cut potatoes (Argon gas 병용처리가 신선편이 감자의 품질에 미치는 영향)

  • Son, Hyun-Ju;Moon, Kwang-Deog
    • Food Science and Preservation
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    • v.21 no.2
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    • pp.163-169
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    • 2014
  • The effect of the combined argon (Ar) gas packaging treatment on the browning of fresh-cut potatoes was studied. Fresh-cut potatoes were prepared for the following six groups: dipping distilled water for 1 minute and air packaging (Cont); dipping in distilled water for 1 minute and argon gas packaging (AR); dipping in 1% ascorbic acid for 1 minute and air packaging (AA); dipping in 1% ascorbic acid for 1 minute and argon gas packaging (AAR); blanching at $35^{\circ}C$ for 30 minutes and air packaging (BL); and blanching at $35^{\circ}C$ for 30 minutes and argon gas packaging (BAR). The potatoes were washed, peeled, and sliced ($1.5{\times}1.5{\times}1.5$ cm) before treatment. The samples were packed with a 0.04-mm-thick OPP film and were stored at $5^{\circ}C$ for 9 days. During the storage, the $O_2$ concentration decreased in Cont but increased in the AR, AA, AAR, BL, and BAR groups. The $CO_2$ concentration increased during storage. The AR, AAR, and BAR groups showed high $L^*$ and low $a^*$, $b^*$ values (browning index). The growth of the total aerobic bacteria was also inhibited in the AR group. During storage, the PPO activity gradually increased, and the AR group showed lower PPO activity. The AA and AAR groups showed high DPPH radical scavenging activity. It was demonstrated that the argon gas packaging is effective in the quality maintenance of fresh-cut potatoes.