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Effects of NaCl Concentration on the Rancidity Development of Sample Ramyon Products, Deep-Fried Instant Noodles (라면 시제품(試製品)의 산패(酸敗)에 미치는 소금 농도(濃度)의 영향(影響))

  • Kim, Tae-Woong;Heo, Tae-Ryeon;Kim, Dong-Hoon
    • Korean Journal of Food Science and Technology
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    • v.7 no.1
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    • pp.51-56
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    • 1975
  • The effects of various concentration of NaCI, i.e., 1, 2, 2. 5, 3, and 4%, on the rancidity development of samples of Ramyon, deep-fried instant noodles, were studied. Dough for the samples, which was composed of wheat flour, distilled water, and pure NaCI, was prepared at a commercial plant but the deep-frying p개cess for the dough was performed in the laboratory. The products thus obtained were incubated for 50 days at $45.0{\pm}1.0^{\circ}C$. Peroxide and TBA values were determined every 5 days throughout the storage period. The results obtained are as follows. 1) Control and the samples containing 1, 2, 2. 5, and 3% salt had POVs of 8. 7, 9. 1, 9. 0, 9. 2 and 9. 7 respectively after 25 days. The control showed a POV of 19.1 after 45 days whereas the sample Ramyons containing 1, 2, 2. 5, 3, and 4% salt had POVs of 12. 6, 13. 2, 14. 6, 15. 3, and 15. 8 respectively after 30 days. 2) TBA values of Control and the sample containing 1, 2, 2. 5, 3, and 4% salt were 5. 8, 6. 1, 6. 2, 6. 4, 6. 7, and 6. 6 respectively after 15 days. But the control developed a TBA value of 11. 4 after 40 days. The samples containing 1, 2, 2. 5, and 3% salt showed TBA values of 10. 2, 14. 3, 15. 8, and 15. 3 respectively after 30 days whereas the sample containing 4% salt had a TBA value of 13. 8 after 25 days. 3) The relationship between the POVs and the TBA values was linear. However, the regression curves of the POVs and the TBA values indicated progressive increase in the gradients(POV/TBA) with increase in the salt content. 4) From the results of the present study, it was found that although the acceleration of rancidity was not in proportion to the amount of NaCI, definite progressive increase in the rancidity development was observed with increase in the salt content of the sample Ramyons.

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Effect of Steam-Treated Zeolite BEA Catalyst in NH3-SCR Reaction (NH3-SCR 반응에서 스팀 처리된 zeolite BEA 촉매의 영향)

  • Park, Ji Hye;Cho, Gwang Hee;Hwang, Ra Hyun;Baek, Jeong Hun;Yi, Kwang Bok
    • Clean Technology
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    • v.26 no.2
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    • pp.145-150
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    • 2020
  • Nitrous oxide (N2O) is one of the six greenhouse gases, and it is essential to reduce N2O by showing a global warming potential (GWP) equivalent to 310 times that of carbon dioxide (CO2). Selective catalytic reduction (SCR) is a technology that converts ammonia into harmless N2 and H2O by using ammonia as a reducing agent to remove NOx, one of the air pollutants; the process also produces high denitrification efficiency. In this study, the Fe-BEA catalyst was steam-treated at 100 ℃ for 2 h before Fe ion exchange in the fixed bed reactor in order to investigate the effect of the steam-treated Fe-BEA catalyst on the NH3-SCR reaction. NH3-SCR reaction test of synthesized catalysts was performed at WHSV = 180 h-1, 370 to 400 ℃ in the fixed bed reactor. The Fe-BEA(100) catalyst steam-treated at 100 ℃ showed a somewhat higher activity than the Fe-BEA catalyst at 370 to 390 ℃. The catalysts were characterized by BET, ICP, NH3-TPD, H2-TPR, and 27Al MAS NMR in order to determine the cause affecting NH3-SCR activity. The H2-TPR result confirmed that the Fe-BEA(100) catalyst had a higher reduction of isolated Fe3+ than the Fe-BEA catalyst, and that the steam treatment increased the amount of isolated Fe3+ as an active species, thus increasing the activity.

Removal of Red Tide Organisms -1. flocculation of Red Tide Organisms by Using IOSP- (적조생물의 구제 -1. IOSP에 의한 적조생물의 응집제거-)

  • KIM Sung-Jae;CHO Kyu-Dae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.33 no.5
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    • pp.448-454
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    • 2000
  • This study was to examine the physicochemical characteristics of coagulation reaction between ignited oyster shell powder (IOSP) and red tide organisms (RTO), and its feasibility, in developing a technology for the removal of RTO bloom in coastal sea,IOSP was made from oyster shell and its physicochemical characteristics were examined for particle size distribution, surface characteristic by scanning electron microscope, zeta potential, and alkalinity and pH variations in sea water. Two kinds of RTO that were used in this study, Cylindrotheca closterium and Skeletonema costatum, were sampled in Masan bay and were cultured in laboratory. Coagulation experiments were conducted using various c(Incentrations of IOSP, RTO, and a jar tester. The supernatant and RTO culture solution were analyzed for pH, alkalinity, RTO cell number, IOSP showed positive zeta potentials of $11.1{\~}50.1\;mV\;at\;pH\;6.2{\~}12.7$, A positive zeta potential of IOSP slowly decreased with decreasing pNa 4,0 to 2,0. When pNa reached zero, the zeta potential approached zero, When a pMg value was decreased, the positive zeta potential of IOSP increased until pMg 3.0 and decreased below pMg 3.0. IOSP showed 4.8 mV of positive zeta potential while RTO showed -9.2 mV of negative zeta potential in sea water. A positive-negative EDL (electrical double-layer) interaction occurred between $Mg(OH)_2$ adsorption layer of IOSP and RTO in sea water so that EDL attractive force always worked between them. Hence, their coagulation reaction occurred at primary minimum on which an extreme attractive force acted because of charge neutralization by $Mg(OH)_2$ adsorption layer of IOSP. As a result, the coagulation reaction was rapidly processed and was irreversible according to DLVO (Deriaguin-Landau-Verwey-Overbeek) theory. Removal rates of RTO were exponentially increased with increasing both IOSP concentration and G-value. The removal rates were steeply increased until 50 mg/l of IOSP and reached $100{\%}\;at\;400\;mg/l$ of IOSP. Removal rates of RTO were $70.5,\;70.5,\;81.7,\;85.3{\%}$ for G-values of $1,\;6,\;29,\;139\;sec^(-1)$at IOSP 100 mg/l, respectively. This indicated that mixing (i.e., collision among particles) was very important for a coagulation reaction.

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Immunoenhancing Effects of Conjugated Linoleic Acid on Chemotactic Activity of Porcine Peripheral Blood Polymorphonuclear Cells (돼지 말초혈액 다형핵 백혈구의 유주성에 있어서 conjugated linoleic acid의 면역증강효과)

  • Kim, Ju-hyang;Chung, Chung-soo;Lee, Chul-young;Yang, Mhan-pyo
    • Journal of Veterinary Clinics
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    • v.20 no.1
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    • pp.1-6
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    • 2003
  • Immunoenhancing effects of conjugated linoleic acid (CLA) isomers (l0t-l2c CLA, 9c-11t CLA, CLA mixture, 9c-11c CLA and 9t-11t CLA) on chemotactic activity of porcine peripheral blood polymorphonuclear cells (PMN) were examined. The chemotactic activity of PMN was evaluated by a modified Boyden chamber assay. CLA isomers at higher concentration of 50 to 200$\mu$M exhibited a low viability of cells by trypan blue exclusion. CLA isomers were used at concentration of 20uM showing no cytotoxic effect and high cell viability. CLA isomers themselves were not active or slight chemotactic for PMN. But culture supernatant from mononuclear cells (MNC) treated with 10t-12c CLA, 9c-11t CLA and CLA mixture except for 9c-11c. CLA and 9t-11t CLA enhanced remarkably chemotactic activity or porcine PMN PMN migration by culture supernatant from MNC treated with CLA mixture was found to be true chemotaxis by checkboard assay. This migration was also induced by porcine recombinant interleukin (rIL)-8. PMN chemotaxis caused both culture supernatant from MNC treated with CLA mixture and porcine rIL-8 was inhibited in a dose-dependent manner by addition of anti-porcine IL-8 polyclonal antibody. Therefore, these results strongly suggested that CLA (10t-12c CLA, 9c-11t CLA and CLA mixture) could stimulate porcine MNC to release and IL-8 like chemotactic activity.

Genetic Diversity in the Major Surface Protein Gene of Theileria Buffeli in Korean Indigenous Cattle (국내 한우의 타일레리아 주요항원단백질 유전자의 다양성)

  • Yu, Do-Hyeon;Li, Ying-Hua;Chae, Joon-Seok;Park, Jin-Ho
    • Journal of Veterinary Clinics
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    • v.27 no.5
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    • pp.501-507
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    • 2010
  • The aim of the current study was to analyze the diversity of the major surface protein (Msp) gene in Theileria buffeli, which is known as the major antigenic protein recognized by the immune system of the host. In addition, we characterized the diversification of the Msp gene and its relationship to with the pathogenicity of Theileria. Complete blood counts (CBC) and Theileria 18S rRNA PCR sequence analysis were performed for 177 Korean indigenous cattle (KIC) in Jeju Island. A total of 28 KIC (16 anemic and 12 non-anemic KIC) were then randomly selected based on 18s rRNA PCR positive samples for sequence analysis of the Theileria Msp gene, which was performed twice for each specimen. The resulting 56 Msp gene sequences were classified into five antigenicity types (type I to V), according to the variable region (517-571 bp), which exhibited high similarity (${\geq}$ 98.9%) to several available GenBank sequences (Theileria spp. from China-EU584237; T. sergenti from China-DQ078264; Theileria spp. from Thailand-AB081329; Theileria spp. from Japan-AB218442; T. sergenti from Japan-AB016280). The 56 Msp sequences consisted of 22, 15, 9, 8, and 2 cases of type I to type V Msp genes, respectively. The most prevalent type in both anemic and non-anemic KIC was type I (37.5% in anemic and 41.7% in non-anemic). Among the remaining types, type II was the most prevalent (37.5%) in anemic KIC, while type IV was the most prevalent (25%) in non-anemic KIC. The results of our study help confirm the diversity of Msp gene types and demonstrate that the gene type distribution of Msp genes varies among Theileria-infected KIC in Jeju Island.

Studies on the Relative Durability of Useful Woods Grown in Korea to the Parasitic Wood Destroying Fungi (목재부후균의(木材腐朽菌)의 기생(寄生)에 의한 한국산(韓國産) 유용목재(有用木材)의 비교내후성(比較耐朽性) 연구(硏究))

  • Chung, Dae-Kyo
    • Journal of the Korean Wood Science and Technology
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    • v.15 no.2
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    • pp.1-15
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    • 1987
  • This experiment was undertaken for the purpose of investigation of relative durability about thirty sorts of the korean native wood and nine sorts of the wood destroying fungi Polystictus versicolor, Irpex consors. Poria vaporaria, Merulius lacrymans, Schizophyllum commune, Trametes pini, Lenzites betulina, Paxillus panuoides by means of a laboratory methods. The results obtained are; (from the table 2 to 10) 1. By measuring the percentage of loss in weight with regard to Polystictus versicolor, the sap wood contained in Junipeus chinesis was calculated at 18.2%, therefore it is much higher durability than any others and the sap wood contained in Pinus densiflora was measured at 44.10%, therefore it is much lower durability than any others. 2. By measuring the percentage of loss in weight with regard to Irpex consors, the heart wood contained in Butula schmidtii was calculated at 1.23%, therefore durability is very high and the heart wood contained in Quercus dentata was calculated at 26.79%, therefore durability is very low. 3. By measuring the percentage of lass in weight with regard to Lenzites betulina, the heart wood contained in Betula schmidtii was calculated at 5.33%, therefore it is much higher durability than any others and the sap wood with regard to Abies holophylla was measured at 45.48%, therefore durability is very low. 4. By measuring the percentage of loss in weight with regard to Poria vaporaria, the sap wood contained in Fraxinus rhynchophylla was calculated at 5.57%, therefore durability is very high and the sap wood contained in Paulownia coreana was calculated at 35.6%, therefore it is much lower durability than any others. 5. By measuring the percentage of loss in weight with regard to Merulius lacrymans, the heart wood contained in Castanea crenata was measured at 0.09% and in the next place, the heart wood contained in Abies holophylla calculated at 0.15% did not decay almost and the sap wood contained in Cornus controversa was measured at 32.88%, therefore it is lower durability than any others. 6. By measuring the percentage of loss in weight with regard to Schizophyllum commune, the sap wood cantained in Junipensis chinensis was calculated at 1.09%, therefore durability is very high and the sap wood contained in Populus deltoides was calculated at 36.87%, it is much lower durability than any others. 7. By measuring the percentage of loss ill weight with regard to Trametes pini, the sap wood contained in Robinia pseudo-acacia was calculated at 1.33%, therefore durability is very high and the sap wood contained in Comus controversa was calculated at 33.19%, it is much lower durability than any others. 8. By measuring the percentage of loss ill weight with regard to Paxillus panuoides. the heart wood contained in Zelkova serrata was calculated at 1.73%, therefore durability is very high and the sap wood contained in Populus deltoides was calculated at 42.30%, therefore durability in very low. 9. By measuring the percentage of loss in weight with regard to Dardalea quercina, the heart wood contained in Castanea crenata was calculated at 0.92%, therefore durability is very high and the sap wood contained in Cornus controversa was calculated at 32.00% therefore durability is very low. The above results are summarized as follows 1. Durability between the heart wood and the soft wood find that it is nonsignificant, while durability is higher heart wood than sap wood. 2. Special sorts including in the element like Castanea cenata, Robinia pseudo-acacia, Juniperus chinensis and heart wood like Betula schmiditii and Styrax obasia are highly durable and soft wood like Cornus controversa, Populus davidiana, Salix koreensis, Celtis jessensis are lowly durable in general. 3. Among the wood destroying fungi Paxillus panuoides is highly durable and as follows. Poria vaporaria, Lenzites betulina and the Daedalea quercina is less in general and Irpex consors, Mersulius lacrymans are a middle degree.

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Molecular Characterization and Phylogenetic Analysis of Season Influenza Virus Isolated in Busan during the 2006-2008 Seasons (부산지역에서 유행한 계절인플루엔자바이러스의 유전자 특성 및 계통분석('06-'08 절기))

  • Park, Yon-Koung;Kim, Nam-Ho;Choi, Seung-Hwa;Lee, Mi-Oak;Min, Sang-Kee;Kim, Seong-Joon;Cho, Kyung-Soon;Na, Young-Nan
    • Journal of Life Science
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    • v.20 no.3
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    • pp.365-373
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    • 2010
  • To monitor newly emerged influenza virus variants and to investigate the prevalence pattern, our laboratory performed isolation of the viruses from surveillance sentinel hospitals. In the present study, we analysed influenza A/H1N1, A/H3N2, B viruses isolated in Busan during the 2006/07 and 2007/08 seasons by sequence analysis of the hemagglutinin (HA1 subunit) and neuraminidase (NA) genes. The isolates studied here were selected by the stratified random sample method from a total of 277 isolates, in which 15 were A/H1N1, 16 were A/H3N2 and 29 were B. Based on the phylogenetic tree, the HA1 gene showed that A/H1N1 isolates had a 96.7% to 97.7% homology with the A/Brisbane/59/2007, A/H3N2 isolates had a 98.4% to 99.7% homology with the A/Brisbane/10/2007, and B isolates had a 96.5% to 99.7% homology with the B/Florida/4/2006(Yamagata lineage), which are all the vaccine strains for the Northern Hemisphere in 2008~2009 season. In the case of the NA gene, A/H1N1 isolates had 97.8% to 98.5% homologies, A/H3N2 isolates had 98.9% to 99.4% homologies, and B isolates had 98.9% to 100% homologies with each vaccine strain in the 2008~2009 season, respectively. Characterization of the hemagglutinin gene revealed that amino acids at the receptor-binding site and N-linked glycosylation site were highly conserved. These results provide useful information for the control of influenza viruses in Busan and for a better understanding of vaccine strain selection.

Occurrence and Repression of Off-Odor in Cooked Rice during Storage under Low Temperature Warming Condition of Electric Rice Cooker (전기밥솥으로 저온보온한 쌀밥의 이취 발생 및 억제)

  • Park, Seok-Kyu;Ko, Yong-Duck;Cho, Young-Sook;Shon, Mi-Yae;Seo, Kwon-Il
    • Korean Journal of Food Science and Technology
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    • v.29 no.5
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    • pp.919-924
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    • 1997
  • The changes in physicochemical properties of cooked rice stored in an electric rice cooker at different temperature (63, 66, 69 and $72^{\circ}C$) were investigated. The growth of thermophilic bacteria was gradually increased in all samples with storage time up to 6 hours and increased rapidly afterward. The bacterial growth rate was higher during storage at low temperature than at high temperature, and the bacterial number generally reached the maximum at 18 hours of the storage. The number of bacteria in sample stored at $63^{\circ}C$ was increased to $10^6$ CFU/g after storage for 6 hours. The heat treatment at 6 hours of storage decreased the bacterial number to $10^5 $ CFU/g at 8 hours of storage. Bacterial number was gradually increased with storage time after the first heat treatment. When the sample was reheated after 8 hours of storage, the bacterial number was reduced to the level at which off-odor was not detected after storage for 24 hours. During the storage, moisture content of heat-treated sample was lower than that of sample stored at $63^{\circ}C$ but higher than that of sample stored at $72^{\circ}C$. The L value of heat-treated sample was higher than that of the sample stored at $72^{\circ}C$, but lower than that of the sample stored at $63^{\circ}C$. The b value showed an opposite trend to the L value with regard to the storage temperature. Changes in texture were not remarkable during the storage for the sample heat-treated and stored at low temperature. The occurrence of off-odor and browning was depressed in the heat-treated sample, and the texture and overall eating quality were more acceptable than the samples stored at low temperature.

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Seedling Emergence and Growth Affected by Priming and $GA_3$ Treatments to Three Campanulan Plant Seeds (Priming과 $GA_3$ 처리에 따른 도라지, 더덕 및 만삼의 출아(出芽)와 생장(生長))

  • Kang, Jin-Ho;Kim, Dong-Il;Kang, Shin-Yun;Shim, Young-Do;Han, Kyung-Soo
    • Korean Journal of Medicinal Crop Science
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    • v.5 no.4
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    • pp.307-313
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    • 1997
  • Seed germination test done in laboratory does not coincide with field emergence in general. The experiments were carried out to examine the effect of priming and $GA_3$, treatment to seeds of Platycodon grandiflorum; Codonopsis lanceolata and C. pilosula on lapsed time to first seedling emergence, seedling emergence, morphological characters and growth and the cause of poor emergence of C. pilosula. No-treatment as Control (water), priming or $GA_3$ treatment was done with only distilled water for 2 days, $CA(NO_3)_2$ 150 mM for 2 days or $GA_3$ 0.1 mM for 3 days, respectively. Seedling emergence rate was counted every 2 days but morphological characters and dry weight of shoot and root were measured on 38 days after sowing. Their internal seed structures were examined with Scanning Electron Microscope. C. pilosula had poorer seedling emergence rate than P grandiflorum and C. lanceolata showing nearly same rate: Compared to the other treatment (s) P. grandiflorum displayed higher rate in priming and $GA_3$, treatments but C. lanceolata or C. pilosula did the greatest rate in only $GA_3$ or priming treatment, respectively. $GA_3$ treatment to seeds of P. grandiflorum and C. lanceolata shortened the lapsed time to seedling emergence in comparison with Control, 2-days water imbibition before sowing. In all the species plant height and number of leaves per seedling became shorter and less in priming treatment than the other treatments except plant height of C. Pilosula while their hypocotyl length was nearly same in all treatments. Although priming treatment had nearly similar effect to morphological characters, $GA_3$ treatment forced greater shoot, root and aftermath total dry weight per seedling. Poor seedling emergence of C. pilosula was caused by its seed defect like cleavage or lack of embryo, poor development of embryo and endosperm or their separation.

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The Development and Life Table Parameters of Tetranychus kanzawai (Acarina: Tetranychidae) on Leaves of 'shiranuhi' and Japanese Violet in the Laboratory (한라봉과 왜제비꽃 잎에서 차응애의 발육과 생명표 통계량)

  • Hyun, Heejeong;Kim, Subin;Kim, Dong-Soon
    • Korean journal of applied entomology
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    • v.59 no.2
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    • pp.153-163
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    • 2020
  • This study was conducted to evaluate the fitness of Tetranychus kanzawai Kishida on different host plants: young and old leaves of the mandarin orange 'shiranuhi' ((Citrus unshiu × C. sinensis) × C. reticulata), Japanese violet (Viola japonica Langsd.) and kidney bean (Phaseolus vulgaris L.). The development and oviposition experiments were conducted at constant temperatures (20, 25 and 30℃) and a life table parameters were estimated. T. kanzawai could complete it's development on 'shiranuhi' young leaves, japanese violet and kidney bean, while all died during the immature period on 'shiranuhi' old leaves. The total developmental period of T. kanzawai feeding on 'shiranuhi' young leaves was 17.4, 13.4 and 10.2 days at each temperature, respectively, which was longer than 16.1, 9.5 and 7.0 days of kidney bean. The female longevity of T. kanzawai on young leaves of 'shiranuhi' were 19.1, 15.0 and 12.3 days at each temperature, respectively, and there was no significant difference from 22.1, 14.1 and 10.9 days investigated from kidney bean. The fecundity was 18.1, 23.9 and 17.8 eggs per female, which was less than them of japanese violet and kidney bean at each temperature, respectively. As a result of estimating the life table parameters based on the experimental data, intrinsic rate of increase (rm) were significantly different from each other, and appeared in the following order: kidney (0.1542, 0.2563 and 0.3251), japanese violet (0.1087, 0.2007 and 0.2673) and 'shiranuhi' young leaves (0.0868, 0.1002 and 0.1217) at each temperature, respectively. Finally, the management strategy against T. kanzawai in citrus orchards was discussed based on the results.