• Korean journal of applied entomology
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• v.30 no.2
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• pp.106-110
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• 1991

The mode of inheritance of resistance to fenvalerate in the diamondback moth (Plutella xylostella L.) was studied using insecticide susceptibility and mixed function oxidase tests. Tehre were no differences in the concentration-mortality relationships between $F_1$ progenies $(S_{female}\timesR_{male},\;R_{female}\timesS_{male})$ obtained from reciprocal crosses with the susceptible and fenvalerate-selected strains(R), indicating the absence of sex-linked inheritance. Degree of dominance of the $F_1$ progenies $(S_{female}\timesR_{male},\;R_{female}\timesS_{male})$ were -0.50 and -0.46, respectively, in the insecticide susceptibility test and -0.85 and -0.81, respectively, in the mixed function oxidase test. These results suggest that inheritance of fenvalerate resistance is controlled by and incompletely recessive autosomal gene.

• The Korean Journal of Pesticide Science
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• v.9 no.4
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• pp.365-373
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• 2005

This study was carried out for looking into the status of susceptibility of pest insects to insecticides. Each insect Brown planthopper(BPH), Green leaf hopper(GLH), Smaller brown plant hopper(SBPH), Rice water weevil(RWW), were captured at various areas where the host crops were being cultivated and the susceptibility level of each pest insect was investigated. The susceptibility of each pest insect varied by insect species and areas where they were caught. BPHs kept higher level of susceptibility comparing to susceptible reference strain except to most of tested insecticides except imidacloprid (Resistance ratio was 68). The susceptibilities of GLH and SBPH to most of insecticides for their control did not developed markedly since 1976 except fipronil and imidacloprid which is widely used for WRR control. The insecticides used for control of WRR were very effective even at the concentration of one fourth of recommending concentration, but in 2000 suwon strain of WRR showed markedly reduction of susceptibility to carbofuran.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.557-565
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• 2017

For our survey of insecticidal resistance of Palm thrips (Thrips palmi Karny), we established the discriminating time (DT) and concentration (DC) of nine insecticides, and we conducted a bioassay about seven local populations via leaf-dipping methods. The discriminating times of the recommended concentration (RC) were 24 h at emamectin benzoate EC and spinetoram SC, 48 h at chlorfenapyr EC, 72 h at spinosad SC, cyantraniliprole EC, acetamiprid WP, dinotefuran WG, imidacloprid WP and thiacloprid SC after treatment. The DC estimated the concentration which showed the difference within the mortalities of these local populations. The DCs were emamectin benzoate EC $0.013mg\;L^{-1}$ (RC, $10.8mg\;L^{-1}$), spinetoram SC $0.125mg\;L^{-1}$ (RC, $25.0mg\;L^{-1}$), chlorfenapyr EC $0.25mg\;L^{-1}$ (RC, $50.0mg\;L^{-1}$), spinosad SC $0.083mg\;L^{-1}$ (RC, $50.0mg\;L^{-1}$) and cyantraniliprole EC $5.0mg\;L^{-1}$ (RC, $50.0mg\;L^{-1}$), and DCs of neonicotinoids were their RCs, that is, acetamiprid WP (RC, $40.0mg\;L^{-1}$), dinotefuran WG (RC, $20.0mg\;L^{-1}$), imidacloprid WP(RC, $50.0mg\;L^{-1}$) and thiacloprid SC (RC, $50.0mg\;L^{-1}$). From our investigation into the resistance of the local populations with DT and DC application, the neonicotinoid insecticides have shown a high resistant level for all the local populations, and the other insecticides have demonstrated low or non-resistance. In the use of neonicotinoid insecticides to control Palm thrips, one must take caution. As a result, the establishment of DT and DC in the single dose bioassay method was helpful for surveying the insecticide response dynamics and the development of an insecticide resistance management strategy.

• The Korean Journal of Pesticide Science
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• v.5 no.1
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• pp.30-35
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• 2001

Diamondback moth (Plutella xylostella L.) recently became a single worst insect which is not controlled effectively by organophosphorus and carbamate insecticides in Kangwon alpine croplands. The objective of this study was to determine if diamondback moth has developed a resistance to organophosphorus and carbamate insecticides. Resistance of diamondback moth, collected at Keichon, Jangpyong Taebaek, Chunchon, and Hongchon, was determined by the concentration required to kill fifty percent of population, $LC_{50}$. Their response of resistance varied to insecticides and locations: Taebaek populations were 35 and 70 times more resistant to chlorpyrifos and fenitrothion, respectively, than susceptible(S) population. Hongchon populations were 94 and 254 times more resistant to chlorpyrifos and fenitrothion, respectively, than S population. In addition, Chunchon populations were 37 and 19 times more resistant to profenofos and benfuracarb, respectively, than S population. However, the field populations did not differ in resistance to diazinon, phenthoate, flupyrazofos, carbofuran, and furathiocarb. This study show that field populations of diamondback moth found in Kangwon alpine vegetable croplands have developed a resistance and/or multiple resistance to some insecticides, implying that farmers are losing organophosphorus and carbamate insecticide options for selective control in vegetable crops.

• Journal of Preventive Medicine and Public Health
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• v.3 no.1
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• pp.47-49
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• 1970

Laboratory susceptibility tests with various insecticides against houseflies(Musca domestica L.) were simultaneously conducted with larvae. As a result of these experment the following conclusion has been obtained. 1. The relative ratio to various insecticidal effects were naled>DDVP>diazinon>${\gamma}-BHC$>malathion>dieldrin>DDT in houseflies larvae. 2. It was noted that resistance to various insecticides in larvae was in proportion to resistance in adults.

• Entomological Research
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• v.48 no.5
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• pp.400-404
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• 2018

In this study, we investigated resistance to the organophosphates chlorpyrifos in Tunisian populations of Culex pipiens pipiens. Three field populations were collected from Northern and central Tunisia between 2003 and 2005 and used for the bioassays tests. Our results registered moderate and high levels of resistance to chlorpyrifos which ranged from 33.8 to 111. The chlorpyrifos resistant populations were highly resistant to propoxur indicated an insensitive acetylcholinesterase 1 (AChE 1). The highest frequency of AChE 1 resistant phenotypes (64%) was recorded in the most resistant population (sample # 1). Bioassays conducted in the presence of synergists showed that not esterases were involved as the resistance mechanism to chlorpyrifos. However, CYP450 was partly involved in the resistance of the most resistant sample (# 1). Starch electrophoresis showed that three esterases were present in studied samples: A2-B2, A4-B4 and B12. Results are discussed in relation to the selection pressure caused by insecticide treatments.

• Korean journal of applied entomology
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• v.17 no.2 s.35
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• pp.75-80
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• 1978

The study was conducted to determine the inherited properties of the MEB resistance to natural population of the small brown plant-hopper(Laodelphax striatelluss). The plant-hoppers were collected from the natural population of Naju area where the highest insecticide resistance of MEF to the green rice leaf hopper (Nephotettix cincticeps) have been examined in 1976. And Naju collections were crossed to the susceptible Lab stock to examine the MEP resistance in the $F_1,\;BC_1F_1\;and\;F_2$ and $F_2$ populations. Ail the data were analyzed by the probit method. There was a difference in MEP resistance between Naju collection and susceptible Lab stock, showing $LD_{50}$ value of the former was 0.0029ug/insect compared to 0.0008ug/insect for the later. The $LD_{50}$ values and dosage-mortality lines of the $F_1$ and $BC_1F_1$ tended to close their resistant parent. and it was considered that the character of the MEP resistance in the Naju collection of the small brown plant hopper was controlled by the genetic traits. However, $LD_{50}$ value and dosasage-mortality lines of the $F_2$ populations were intermediate to their parents, it would be conclusive that the trait will be governed by a interaction of the genes or factors rather than the single genic control.

• Korean journal of applied entomology
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• v.25 no.3 s.68
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• pp.151-157
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• 1986

Population of the green peach aphid, Myzus persicae(Sulz.), were successively selected(up to 20th generation) in the laboratory by the insecticide oxydemeton-methyl (Metasystox-R 25Ec) and the resistance was linearly increased with the selected generations. The population developed 355.5-to 359.9-fold resistance to oxydemeton-methyl at 20th generation-selection. The population showed cross resistance to the insectides cypermethrin(770.1-to 778.5-fold), acephate(25.6-to 33.2-fold) and pirimicarb(3.4-to 3.6-fold). The different esterase isozymes were detected by the electrophoresis from the selected and non-selected strains and the band of the ${\beta}-2$ from the selected strain showed greater esterase activity than that of the non. selected strain.

• Parasites, Hosts and Diseases
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• v.58 no.6
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• pp.709-714
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• 2020

Knockdown resistance (kdr) mutations in the voltage-gated sodium channel (VGSC) of mosquitoes confer resistance to insecticides. Although insecticide resistance has been suspected to be widespread in the natural population of Aedes aegypti in Myanmar, only limited information is currently available. The overall prevalence and distribution of kdr mutations was analyzed in Ae. aegypti from Mandalay areas, Myanmar. Sequence analysis of the VGSC in Ae. aegypti from Myanmar revealed amino acid mutations at 13 and 11 positions in domains II and III of VGSC, respectively. High frequencies of S989P (68.6%), V1016G (73.5%), and F1534C (40.1%) were found in domains II and III. T1520I was also found, but the frequency was low (8.1%). The frequency of S989P/V1016G was high (55.0%), and the frequencies of V1016G/F1534C and S989P/V1016G/F1534C were also high at 30.1% and 23.5%, respectively. Novel mutations in domain II (L963Q, M976I, V977A, M994T, L995F, V996M/A, D998N, V999A, N1013D, and F1020S) and domain III (K1514R, Y1523H, V1529A, F1534L, F1537S, V1546A, F1551S, G1581D, and K1584R) were also identified. These results collectively suggest that high frequencies of kdr mutations were identified in Myanmar Ae. aegypti, indicating a high level of insecticide resistance.

• Korean journal of applied entomology
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• v.63 no.1
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• pp.33-42
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• 2024

The green peach aphid, Myzus persicae is a representative agricultural insect pest that is polyphagous and causes serious damage to tobacco, potatoes, peppers, cabbage, and peaches. In this study, we analyzed the level of development of insecticide resistance to λ-cyhalothrin, imidacloprid, and flupyradifurone and the point mutations (R81T, L1014F, M918L) in 12 field populations of M. persicae. In addition, the expression level of CYP6CY3, a cytochrome P450 gene, was analyzed through qRT-PCR. As a result, λ-cyhalothrin showed high resistance ratio (RR) of > 200 in all 12 populations. Imidacloprid and flupyradifurone showed high RR of >200 in YS, UR, HY, and WJ populations. The R81T was detected in approximately 50%, L1014F in approximately 33.3%, and M918L in 100% of the 12 populations. Additionally, the expression level of subunit CYP6CY3 was highest in imidacloprid-resistant population (YS). These results suggest that M918L point mutation can be used as λ-cyhalothrin-resistance molecular diagnostic and R81T point mutation and the high expression of CYP6CY3 can be used as imidacloprid-resistance molecular diagnostic markers.