• Korean journal of applied entomology
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• v.55 no.4
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• pp.377-381
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• 2016

The Baermann funnel method requires approximately four Kimwipe tissues for research a nematode count under a stereo microscope. To select more efficient and economical nematode extraction paper for nematode extraction, 15 different kinds of tissue papers were tested and compared with Kimwipe tissues. Nematode species used in the extraction efficiency tests include juvenile (J2) of Heterodera sp., J2 of Meloidogyne sp., Pratylenchus sp., Rhabditis sp., Acrobeloides sp., Panagrolaimus sp., Poikilolaimus sp. and Diplogasterida. The extraction efficiency varied between 42.0 to 88.8%. Considering costs, extraction efficacy, and clarity, the Pulling Kitchen Towel (Monalisa Co., Korea) is the best tissue, with clarity A, isolation efficiency of 69.4% (not significantly different compared to Kimwipe 1 ply 88.8%), and 1/2 costs per isolation of Kimwipe 2 ply.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.405-412
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• 2016

Infestation of adults and pupae of sweetpotato whitefly, Bemisia tabaci, on paprika (Capsicum annuum var. angulosum) grown in greenhouses in Jinju, Gyeongnam province during 2014was determined by counts of the number of target stage of B. tabaci per leaflet. Binomial sampling plans were developed based on the relationship between the mean density per leaflet (m) and the proportion of leaflets infested with less than T whiteflies ($P_T$), according to the empirical model $(({\ln}(m)={\alpha}+{\beta}({\ln}(-{\ln}(1-P_T))))$. T was defined as the tally threshold, and set to 1, 2, 3, 4, 5 (adults) and 1, 3, 5, 7 (pupae) per leaflet in this study. Increasing the sample size, regardless of tally threshold, had little effect on the precision of the binomial sampling plan. Based on the precision of the model, T = 1 was chosen as the best tally threshold for estimating densities of B. tabaci adults and T = 3 was best tally threshold in B. tabaci pupae. Using the results obtained in the greenhouse, a simulated validation of the developed sampling plan by RVSP (Resampling Validation for Sampling Plan) demonstrated the plan's validity. Above all, the binomial model with T = 1 and T = 3 provided reliable predictions of the mean densities of B. tabaci adults and pupae on greenhouse paprika.

• Korean journal of applied entomology
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• v.54 no.3
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• pp.159-167
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• 2015

In order to establish B. tabaci control in paprika greenhouses a fixed-precision-level sampling plan was developed. The sampling plan consisted of spatial distribution analysis, a sampling stop line, and decision making. Sampling was conducted simultaneously in two independent greenhouses (GH 1, GH 2). GH 1 and 2 were surveyed every week for 22 consecutive weeks, using 19 sampling locations in GH 1 and 9 sampling locations in GH 2. The plant in both greenhouses were divided into top (180-220 cm from the ground), middle (80-120 cm from the ground) and bottom (30-70 cm from the ground) sections and B. tabaci adults and pupae were observed on three paprika leaves at each position and recorded separately. GH 2 data were used to validate the fixed-precision sampling plan, which was developed using GH 1 data. In this study, spatial distribution analysis was performed using Taylor's power law with the pooled data of the top and bottom position (B. tabaci adults), and the middle and bottom positions (B. tabaci pupae), based on a 1-leaf sampling unit. Decision making was undertaken using the maximum of action threshold in accordance with previously published method, and the value was decided by the price of the plants. Using the results obtained in the greenhouse, simulated validation of the developed sampling plan by RVSP (Resampling Validation for Sampling Plan) indicated a reasonable level of precision.

• Korean journal of applied entomology
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• v.37 no.2
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• pp.151-157
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• 1998

Infestations of two spotted spider mite (TSSM), Tetranychus urticae Koch, on glasshouse rose (Rosa sp.) grown by an arching method, were determined by counts of the number of TSSM per leaflet in Buyeo, Chungnam Province, for a 2-yr period. Binomial sampling plans were developed based on the relationship between mean density per leaflet (m), and proportion of leaflets infested with ( T mites (PT), according to the empirical model In (m) = a+p In (-ln (1 -PT)). T was defined as tally threshold, and set to 1, 3, 5, 7, and 9 mites per leaflet. Increasing sample size had little effects on the precision of the binomial sampling plan, regardless of tally threshold. However, the precision increased with higher tally thresholds. There was a negligible improvement in precision with T ) 7 mites per leaflet. T= 7 was chosen as the best tally threshold for estimating densities of TSSM based on the precision of the model. Independent data set was used to evaluate the model. The binomial model with T= 7 provided reliable predictions of mean densities of TSSM observed on the commercial glasshouse roses.

• Korean journal of applied entomology
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• v.62 no.4
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• pp.299-305
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• 2023

Bemisia tabaci is one of polyphagous insect pests that transmits Tomato Yellow Leaf Curl Virus (TYLCV) and Cassava Brown Streak Disease (CBSD). Insecticides are primarily applied to control B. tabaci, but it has limits due to the development of resistance. As a result, a fixed precision sampling plan was developed for its integrated pest management (IPM). The tomato plants were divided into top (more than 130cm from the ground), middle (70 cm to 100 cm above the ground), and bottom (50 cm or less above the ground) strata, before visual sampling of the larvae of B. tabaci. The spatial distribution analysis was conducted using Taylor's power law coefficients with pooled data of top, middle, bottom strata. Fixed precision sampling plan and control decision-making were developed with precision levels and action threshold recommended from published scientific papers. To assess the validation of the developed sampling plans, independent data not used in the analysis were evaluated using the Resampling Validation for Sampling Plan (RVSP) program.

• Journal of Apiculture
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• v.32 no.3
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• pp.171-180
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• 2017

Slow Bee Paralysis Virus (SBPV) is a pathogenic virus against honeybee and bumblebee, causes the death of adult bee by paralyzing the fore-leg of bee. In this study, for rapid detection of SBPV from bumblebee, SBPV-specific Ultra-rapid Reverse transcription PCR was developed. After optimizing of SBPV-specific Ultra-rapid PCR, the existence of $1.0{\times}10^8$ SBPV-specific DNA molecules could be recognized in 3 minute and 35 seconds. Even $1.0{\times}10^1$ molecules of SBPV-specific DNA could be measured with quantitative manner. Meanwhile, from both imported bumblebee and bumblebee produced in Korea, SBPV were detected using proposed method. In the laboratory as well as in the field, SBPV-specific Ultra-rapid Reverse transcription PCR would be applied and might be expected as useful tools at production of bumblebee or inspection for the import and export system of bumblebee.

• The Korean Journal of Zoology
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• v.38 no.3
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• pp.417-425
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• 1995

The present study was carried out to investigate the effect of microwave fixation in comparison with that of chemical fixation in preparing the microscopic samples. The microwave fixator was equipped with infrared-temperature sensor, and that was designed to compensate air temperature in the microwave fixator. In the microwave fixation, rat tongue was well preserved in terms of muscular fasciculus and pancreas stained by Feulgen reagents showed clear reaction products in the nucleus. Reaction products by PAS method in duodenal villi appeared specifically at the goblet cells. In electron microscopy, pancreatic cellular components such as secretory granules and collagen bundles were well preserved in both fixations. In aspect of histochemical reaction and electron microscopy, high quality was due to the protein content of microwave fixed specimen. The microwave fixation method saved total duration engaging microscopic preparation.

• Korean journal of applied entomology
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• v.31 no.2
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• pp.122-132
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• 1992

Experiments were conducted to establish an in vitro AChE inhibition test system to evaluate the potency of AChE inhibition of new chemical compounds. For a fixed time inhibition test, optimal inhibition (incubation) time to evaluate their AChE inhibition potency was 10 min. for AChE inhibitors such as DFP, DDVP, and paraoxon. The concentration of new chemical compounds with an ester group for evaluation of their inhibition potency was 10 $\mu$M under 10 min. preincubation conditions. However, the stepwise inhibition test with higher concentrations seemed to be needed for other chemical compounds. For a progressive inhibition test to calculate inhibition constants such as $K_d$, $K_3$ and $K_i$, extremely low $K_d(1.3\times10-^85.6\times10^{-7})$ and $K_3$(0. 21-0.27 $min^{-1}$) were observed under lagged preincubation time (0.8-13.3 min) and low in¬hibitor concentrations $(1\times10-^92\times10-^6M)$. However, this method seemed to be useful for comparison of AChE inhibition potency among inhibitors. Differences in inhibition potency among DFP, paraoxon, and KH501 were due to the differences in $K_d$, in other words, differences in affinities between inhibitors and AChEs. Therefore, AntiChE screening should consist of two steps. The first step is to evaluate the potency of AChE inhibition based on $I_50$ valuse obtained from fixed time inhibition tests. The second step is to study inhibition patterns and characteristics of chemical compounds selected in the first step.