• Korean journal of applied entomology
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• v.53 no.1
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• pp.7-13
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• 2014

This study was performed to investigate the response of the lacewing Chrysopa cognata to both Aphis gossypii-induced plant volatiles and lacewing-derived volatiles. The results of a Y-tube olfactometer bioassay showed that more C. cognata males were attracted to green pepper plants infected with A. gossypii than to uninfected green pepper plants alone or clean air and C. cognata males were attractive to C. cognata females. Gas chromatography-electroantennographic detection (GC-EAD) analysis showed that the antennae of C. cognata females elicited EAD-active responses to the volatiles entrained from A. gossypii-infected green pepper plants. 4-Ethylacetophenone, 3-ethylbenzaldehyde, 3-ethylacetophenone, and 4-ethylbenzaldehyde from A. gossypii-induced green pepper volatiles, and (Z,Z)-4,7-tridecadiene, (Z)-4-tridecene, and (Z)-4-undecene from C. cognata female entrainment were elucidated by further analysis using GC coupled nuclear magnetic resonance spectroscopy. Of the A. gossypii-induced plant volatiles identified in this study, 4-ethylacetophenone and 3-ethylbenzaldehyde significantly increased the attraction of C. cognata males to nepetalactol, but (Z)-4-tridecene and (Z)-4-undecene did not. (Z,Z)-4,7-Tridecadiene significantly reduced the attractiveness of nepetalactol to C. cognata.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.389-395
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• 2012

Stored grain insects appear frequently as grains are harvested, stored, and distributed on the market. Producers mostly depend on chemical fumigants to control and repel insect pests, but this application of chemicals may cause side effects for humans and the environment. Safer control approaches, including the use of natural products are required, and in this study, we assessed the control effect of essential oils on stored grain insects. The essential oils of 8 plant species from 6 families were tested for their fumigant toxicity and repellent effects using a Y-tube Olfactometer against Sitophilus zeamais adults. Pennyroyal and tea tree oil respectively exhibited 97% and 63% mortality at $10{\mu}{\ell}L^{-1}$ air concentration in tested fumigant toxicity. Of particular note, pennyroyal oil ($LT_{50}$, hour=3.87) showed higher adulticidal activities than tea tree oil ($LT_{50}$, hour=4.09). When assessing repellent effects, using a Y-tube Olfactometer at $10{\mu}{\ell}$/filter paper concentration, the cedarwood, cinnamon, cypress, patchouli and pennyroyal essential oils showed potent repellent activities against Sitophilus zeamais adults. Cinnamon, cypress and pennyroyal essential oils showed notably high repellent activities of 82.4%, 80.0% and 86.7%, respectively, at $1{\mu}{\ell}$/filter paper concentration.

• Korean journal of applied entomology
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• v.60 no.3
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• pp.315-322
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• 2021

This study investigated the acaricidal and repellent activities of various plant extracts and Cnidium officinale-derived materials against Haemaphysalis longicornis. Among the 24 methanolic plant extracts, C. officinale showed the highest acaricidal activity (93.3%) against H. longicornis. Platycodon grandiflorus, Phytolacca americana, Magnolia denudata, Houttuynia cordata, C. officinale, and Pueraria montana showed significant differences in their repellent activity. Consequently, the activity of solvent-fractionated materials and the derived material of the C. officinale, was investigated and a 90% acaricidal effect was observed three days after hexane fraction treatment, indicating that the repellent response was statistically significant. Butylidenephthalide, which is a C. officinale-derived compound, showed 90% acaricidal activity seven days after treatment. Additionally, all H. longicornis moved to the untreated area in the t-tube olfactometer experiment, confirming the repellent activity of butylidenephthalide. Therefore, the results of this study suggest the use of C. officinale crude extract and butylidenephthalide as potent acaricidals and repellents against H. longicornis, respectively.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.30 no.4
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• pp.13-20
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• 2007

The aim of this study was to investigate effects of odor intensity on the olfactory sensibility and sensibility structure. Three odor samples(B, C, and D) of T&T olfactometer were selected by the preference rank : the lowest preference(C) ; the moderate one(B) ; and the highest one(D). Three levels(-1, +1, and +3) of odor intensity at each sample were presented to 50 subjects(25 female, 25 male), and the olfactory sensibility was rated by using semantic differential scale composed 25 sensibility characteristics. At each sample, the olfactory sensibility was significantly affected by the odor intensity. Moreover, the structure of olfactory sensibility was influenced by the odor intensity. However, two sensibility factors such as 'aesthetics' and 'intensity' were common factors, whereas 'mildness', 'complexity', and 'activity' were unique factors with odor intensity. In conclusion, the olfactory sensibility was significantly affected by the odor intensity and the odor preference.

• Science of Emotion and Sensibility
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• v.5 no.2
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• pp.1-9
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• 2002

It is already known that olfactory susceptibility differ with races and sex. Moreover, with aging both detection and identification about olfactory information were impaired. For researches about evaluation of the odor with aging, although the subject used, from infants to elderly, was various, the kinds of odor used were restricted to simple alcohol and acetic acid. Also, the evaluation methods were mainly used olfactory test. From over respects , this research was done as follows. Subjects were 19 to 72 years (n=50) whose sense-of-smell functions are normal. They were taken as stability and closed eye state. The odor stimuli were used 100% natural odor of six kinds of Basil, Lavender, Lemon, Jasmine, Ylangylang oil and Skatole , during 60 seconds using olfactometer. ECG, GSR and subjective evaluation were measured, and examined their relevance. Twenty and 40 ages group evaluated Lemon and 60 ages group did Lavender affirmatively. Correlation was seen among RRI, HR, GSR and subjective evaluation for 40 ages group, and it turns out that it is the group which a mature olfactory function most. These results are fully applied not only to development of the classified cosmetics for the age group but to development of the artificial smell and taste.

• Science of Emotion and Sensibility
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• v.10 no.2
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• pp.199-208
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• 2007

The olfactory function of subjects could be different due to various factors such as aging, and such discrepancies influence on the olfactory sensibility. Therefore, the objectives of this study was to investigate changes of olfactory sensibility characteristics and structure in relation to the consideration of olfactory threshold of subject. Stimulants of this study were five standard odor samples of T&T olfactometer, and thirty undergraduates over than 19 years old were tested twice during this study In experiment 1, subjects were given to odor samples which were controlled on the basis of individual olfactory threshold. Whereas, subjects were provided with uncontrolled odor samples which had the same concentration(+1) in experiment 2. Olfactory sensibility characteristics were significantly different with presentation types of odor samples, and these gaps were more higher on condition that the preference of odor sample was not distinct. Moreover, such differences affected the olfactory sensibility structure, and 'esthetic sense', 'intensity', and 'activity' were common factors, but 'friendship' of experiment 1 and 'weight' of experiment 2 were unique factors. In conclusion, the olfactory sensibility characteristics and structure could be different with consideration of olfactory threshold of subject. Overall, this study suggest that the olfactory function and the presentation method of odor sample be regarded as principal consideration factors in the olfactory sensibility evaluation.

• Korean journal of applied entomology
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• v.36 no.1
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• pp.88-95
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• 1997

Olfactometer was used to find the attractiveness of kairomone extracted from gypsy moth (Lymantria dispar) to the egg parasitoid (Ooencyrtus kuvanae). The attractiveness of kairomone extracted from scales and hairs which were attached to the surface of the eggs were higher than that of whole eggs with 79.9% and 67.6% respectively. The probing lantency of the egg parasitoid on the extract of scales and hairs were 115.5 sec. and that of whole eggs were 113.2 sec. Eggs taken from egg mass were shown 91.0% of attractiveness to the egg parasitoid, however only 15% of egg parasitoid were attracted by follicles dissected from the host ovary. The probing latency of egg mass was faster than that of follicles dissected from the host with 84.2 sec. and 114.0 sec. respectively. Egg parasitoid showed the most active attractiveness (88.0%), relatively longer examing period (89.2 sec.) and shorter probing latency (26.8 sec.) to the adhesive materials secreted from reproductive accessory glands of the host. Out of six organic solvents used for the extraction of kairomone from the host egg mass, n-hexane fraction received the most active response from xthe egg parasitoid and the parasitoid reared in vivo showed 3 times higher attractiveness to the n-hexane fraction than that of in vitro.

• Journal of Animal Environmental Science
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• v.14 no.2
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• pp.75-80
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• 2008

High concentration of $NH_3$, $CO_2$, and lots of dust are found in modern densely raising stall system, as results, they provide a negative influence on animal and lamer health, and production ability. Therefore, it is necessary to keep clean the inside of stall air to increase the productivity. A wet type air cleaner has been developed to clean the stall air. The work principle is that the inside air are sucked through the fan, and the rotating discs make a water into a fineness spray and blows into the stall. The spray can take the dust, $NH_3$, and odor from the stall inside air and give back to the circulating water, which can be refreshed in 2 hours interval. In the Present study, we measured the $NH_3$, dust, odor, temperature and humidity in a swine stall that were installed two wet air cleaners with 700 fattening swine with on-mode and off-mode of wet air cleaners. In fall, the concentrations of $NH_3$ in off-mode stall were maximum 24 ppm and minimum 16 prm, and the average was 18.2 ppm. However in on-mode stall the $NH_3$ concentrations were maximum 7ppm and minimum 1ppm, and the average was 2.7ppm. The concentration of $NH_3$ in on-mode was 74% lower than off-mode stall. Odor was measured by olfactometer. In the off-mode stall, the odor unit was 3,800 OU/$m^3$, but in the on-mode stall the odor unit was 2,100 OU/$m^3$ Odor removal efficiency was about 45% in on-mode stall. The dust measure was divided into 3 categories, $PM_{10}$, $PM_{2.5}$ and $PM_{1.0}$. Whereas the $PM_{10}$ showed no significant differences between the tests, $PM_{2.5}$ and $PM_{1.0}$ in the fine particle range reduced remarkably in the on-mode.

• Korean journal of applied entomology
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• v.53 no.4
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• pp.435-440
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• 2014

The number of Bemisia tabaci adults attracted to horseweed, thistle, red bean, cucumber, and tomato plants, as measured by the number stuck to yellow sticky traps, was investigated in a polyvinyl greenhouse for growing tomatoes using organic methods. The number was highest on cucumber plants in the early days of B. tabaci infestation, but was highest on horseweed overall. Of the eight species of beans tested, B. tabaci adults were most attracted to Ultari-Gangnang; however, beans were not effective trap plants for B. tabaci. Measurement of olfactory behavioral response using a four-choice olfactometer showed that B. tabaci adults preferred horseweed to cucumber, eggplant, or tomato. The developmental period of B. tabaci eggs and larvae was shorter at high temperature. At $30^{\circ}C$, the developmental period of eggs and larvae on horseweed were reduced approximately 0.5 and 1 day, respectively, compared to those on cucumber or tomato.

• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.911-921
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• 2015

We evaluated two herbal plants, basil (Ocimum basilicum) and lemon balm (Melissa officinalis), for their potential as repellent plants in the management of striped flea beetle (Phyllotreta striolata), in organic production of chinese cabbage. It was confirmed that striped flea beetle avoided these two herbal plants in olfactometer experiment. We conducted field experiment in which the suppressive effect of the two selected herbal plants and cruciferous crops preferred by striped flea beetle were evaluated through cultivating as inter crops and border crops, respectively. In inter-cropping experiment, unlike in vitro test, the density of striped flea beetle was low in basil- or mustard-intercropping cultivation plot, but high in lemon balm-intercropping cultivation plot. In border cropping experiment, the density of striped flea beetle on chinese cabbage in lemon balm or basil cultivation plot were approximately zero. As a result of this study, we think that border cropping of lemon balm or basil can be used to reduce preventively striped flea beetle of chinese cabbage under organic farming system.