Monitoring and Characterization of Insecticido Resistance in the Cotton Leafworm, Spodoptera littoraiis (Boisd.) (Lepidoptera: Noctuidae)

Elghar Gamal E. Abo,Elbermawy Zeinab A.,Yousef Adel G.,Elhady Hany K. Abd Korean Society of Applied Entomology 2005 Journal of Asia-Pacific Entomology Vol.8 No.4

Resistance to several classes of insecticides was diagnosed in the cotton leafworm (CLW), Spodoptera littoralis (Boisd.), from cotton fields in the Nile Delta Egypt through 2002-2004 seasons. Two types of laboratory bioassays were used for the detection of insecticide resistance. Leaf-dip larval bioassay and discriminating concentration ($LC_{99}$ for susceptible laboratory strain) technique revealed the presence of resistance to insecticides tested. Both larval and adult stages showed relatively similar response to most insecticides tested. However, the glass vial-discriminating concentration technique is particularly more useful when resistance is related to the target-site insensitivity rather than to increased metabolism. The pattern of reversion of resistance to five insecticides was determined in two field strains that have been released from continuous insecticide application and then reared under laboratory conditions for 6-8 generations in the absence of insecticide pressure. It was considered that losing of resistance to cypermethrin in both resistant field strains seemed to be quicker than other insecticides tested, in which resistance ratios decreased from 47.7-fold ($F_o$- parents) to 17.8- fold ($F_6$ generation) in MNF- strain, and from 38.5-fold ($F_o$-parents) to 10.7-fold ($F_6$ generation) in KFR-strain. On the other hand, biochemical assays indicated that both MNF- and KFR-field strains, expressed higher levels of acetylcholinesterase (AChE) activity by 13.2- and 8.4-times, respectively, than that of the susceptible strain. AChE activity was sharply decreased to 1.01- and 1.92- times in MNF- and KFR-strains, respectively, compared to that of susceptible strain, following insect rearing for six successive generations without insecticide pressure. Esterases activity was also decreased 2.02-times ($F_o$) to 1.41 ($F_6$) in KFR-strain and from 2.0-times ($F_o$) to 1.21-times ($F_6$) in KFR-strain, compared to that of susceptible strain. On the other hand, analysis of esterases by native polyacrylamide gel electrophoresis (PAGE) confirmed the association between esterases activity and resistance to insecticides tested in both field strains.

Strategy for Insecticide Resistance Management Approach to IPM

Motoyama, Naoki,Dauterman, W.C. Korean Society of Applied Entomology 1992 한국응용곤충학회지 Vol.31 No.3

Insecticide resistance is a serious is a serious threat to IPM, resulting in various adverse effects not to mention the loss of yield in agriculture. One approach to counter the problem is the disruption of resistance mechanisms. This can be achieved by (1) compounds which show a negative correlation with resistance at the site of action, (2) specific metabolic inhibitors which serve as synergists, or (3) a certain combination of two insecticides producing a joint action. This approach, however, requires certain precautions for the side effects may cause an increase in toxicity to mammals. Owing to the recent advances in theoretical studies on resistance management employing computer simulation and mathematical models, a few principles to reduce the risk of development of resistance have been clarified. They are helpful in designing operational strategies with regard to, for instance, insecticide doses to be applied, mode of application, and choice and nature of the insecticide(s) to be used. For restoration of insecticide susceptibility of a resistant population, reintroduction of susceptible individuals to the resistant population is feasible when certain conditions are met. Natural enemies which developed resistance to insecticides can be an important component of IPM as has been shown in the pest management in apple orchards. After all, the implementation of a successful resistance management program depends upon cooperation between different sigments of the agricutural community. Although resistance is a preadaptive phenomenon, in some cases spontaneous loss of resistance does occur without contamination by susceptible individuals. The instability of resistance in these insects implies the possible existence of a switch machanism controlling the expression of resistance gene(s). Elucidation of such a mechanism may eventually provide us with a new technical approach with which we can combat the problem of insecticide resistance.

한국의 DDT 저항성 몸니와 살충제 저항성 지식의 형성

정준호 대한의사학회 2022 醫史學 Vol.31 No.3

DDT exemplifies success and failure of modern science and technology. Once it was heralded as technological wonder that will deliver human from misery of insect-borne infectious disease. However DDT took dramatic downturn after failure in global malaria eradication program initiated by World Health Organization, with advent of DDT- resistant strain of mosquitoes. Although insecticide resistance has been know since late 19th century, the definitions and mythologies for finding resistance has not been settled until 1950s. This paper argues that discovery of DDT-resistant strain of body lice in prisoners of war camp in Korea during the Korean War provided essential knowledge and opportunity for advancing insecticide resistance studies. Since 1945 to the end of Korean War, US Army sprayed thousands of tonnes of DDT on Korean body and soil. DDT was only went into wide field application since 1943, was still a very new technology. The ways to deliver and utilize DDT was still under the investigation. And Korea, especially during the War, was ideal place to construct such knowledge and place it in the application. The main focus was to control public health threats, such as louse-borne typhus fever. Korean soldiers and prisoners of war exposed to regular dose of DDT, which soon gave rise to DDT-resistant strain of body lice. It was the first major outbreak of insecticide-resistance appeared in insect that has major public health importance. Until early 1950s, mechanisms of resistance, or even definition of insecticide resistance was unclear. Researchers in US Army and Department of Agriculture rushed to find the ways to quantify insecticide resistance. Network of laboratories, connecting Korea-Japan- US, had to devise new laboratory methods to rear, and test body lice. These body lice later migrate to laboratories in US, providing valuable asset for future insecticide resistance research in US. At the same time, laboratory methods of testing resistance in body louse became a standard across the globe, setting new research agenda through World Health Organization. This shows flow of knowledge, along with migration of body louse, during the Korean War. At the same time, this case show who new knowledge is constructed through the expense of involvement of minority populations, such as natives, soldiers, and prisoners of war.

Prevalence and stability of insecticide resistances in field population of Spodoptera litura (Lepidoptera: Noctuidae) from Huizhou, Guangdong Province, China

Xi Wang,Linlin Lou,Jianya Su 한국응용곤충학회 2019 Journal of Asia-Pacific Entomology Vol.22 No.3

The field population of Spodoptera litura from Huizhou, Guangdong Province, China was evaluated for resistance to 21 insecticides, including conventional and new chemistry insecticides. Extreme levels of resistance were observed to metaflumizone and emamectin benzoate with resistance factors of 234.1 and 183.3, respectively. Resistance to abamectin was also high (perhaps extremely high) and over 71.9-fold. The Huizhou population of S. litura possessed high resistance to deltamethrin (96.5-fold) and moderate resistance to beta cyfluthrin and lambda cyhalothrin but remained susceptible to bifenthrin. Moderate resistance to chlorantraniliprole (22.3-fold), endosulfan (22.2-fold), tebufenozide (10.7-fold) and thiodicarb (14.3-fold), and low-level resistance to fipronil, indoxacarb and spinosad were also reported in this population. This field population remained susceptible to acetamiprid, chlorfenapyr, chlorfluazuron, hexaflumuron, chlorpyrifos, pyridalyl and spinetoram. The stabilities of resistance to metaflumizone, emamectin benzoate, deltamethrin, chlorantraniliprole and endosulfan were evaluated, the resistance level decreased when the insecticide stress was removed, suggesting stop of the application of insecticides with high level resistance could be implemented into the resistance management. Because S. litura from Huizhou developed resistance to multiple insecticides, integration of different control practices, especially the rotation of insecticides with biocontrol agents, should be performed in the management of this pest. The results suggested the suspension of the application of insecticide to which S. litura had developed high level of resistance in order to mitigate the resistance status, and the use of the insecticides to which this pest remained sensitive, including spinetoram, pyridalyl, indoxacarb, hexaflumuron, chlorfluazuron, chlorfenapyr and bifenthrin, could be incorporated into the alternating application for resistance management.

Insecticide Resistance Monitoring and Correlation Analysis for the Selection of Appropriate Insecticides Against Nilaparvata lugens (Stål), a Migratory Pest in Korea

Sujeong Min,Si Woo Lee,Byeong-Ryeol Choi,Chang Gyu Park,Si Hyeock Lee,Deok Ho Kwon 한국응용곤충학회 2014 한국응용곤충학회 학술대회논문집 Vol.2014 No.10

Nilaparvata lugens Stål is one of the important migratory pests of rice paddy fields in Korea. Resistance levels to nine insecticides were monitored in 12 local strains and correlation analysis was conducted to determine cross-resistance relationships among the tested insecticides. The local strains revealed 1.3- to 28.0-, 1.6- to 6.0-, 2.8- to 237.0-, 0.6- to 0.9-, and 0.7- to 1.3-fold resistance to carbamates, organophosphates, neonicotinoids, fipronil and etofenprox, respectively. Organophosphates revealed moderate correlations with benzofuranyl methylcarbamate (r = 0.566 - 0.614, p > 0.01). Three neonicotinoids were not correlated each other, but imidacloprid and clothianidin were moderately correlated with several benzofuranyl methylcarbamate and organophosphate insecticides (r = 0.590 - 0.705, p > 0.05), indicating that unknown common factors (such as detoxification enzymes) might contribute to resistance to both insecticides. Fipronil and etofenprox exhibited low levels of resistance and cross-resistance with other insecticides, suggesting their potential as an effective insecticide for field application. Resistance level monitoring and correlation analysis would be valuable for the selection of appropriate insecticides to control insecticide-resistant N. lugenes, a typical migratory pest in Korea.

Residual contact vial method for the rapid on-site detection of insecticide resistance in Thrips palmi

김민주,김경문,Tian-Bo Ding,김주현,정인홍,권덕호,이시혁 한국응용곤충학회 2019 Journal of Asia-Pacific Entomology Vol.22 No.2

A residual contact vial plus water (RCVpW) bioassay method, in which water was supplemented to minimize control mortality, was established to monitor insecticide resistance in field populations of the melon thrips, Thrips palmi. In the RCVpW, median lethal doses (LD 50 ) of six insecticides commonly used in T. palmi control, were determined at 8 h post-treatment, using a susceptible RDA strain according to the RCVpW protocol. Diagnostic doses for on-site resistance monitoring of the six insecticides, which were determined as doses twofold higher than required to achieve LD 90 in the RDA strain, were in the range of 0.299 to 164.3 μg −1 cm 2 . Insecticide resistance levels in five field populations of T. palmi were evaluated to test the applicability of RCVpW in monitoring the pest. Although the RDA strain exhibited 100% mortality to diagnostic doses, field populations showed a reduced mortality in response to all test insecticides, indicating different degrees of resistance. In particular, all test field populations exhibited a significantly low mortality in response to spinosad, suggesting a wide distribution of spinosad resistance. Synergistic bioassay revealed that cytochrome P450-mediated metabolic factor is involved in spinosad resistance in the Korean population. Interestingly, an apparently reduced mortality to emamectin benzoate and chlofenapyr was observed in some field populations, perhaps suggesting uneven distribution of resistance to these insecticides in field populations. Our study showed that the RCVpW protocol can be employed both as an on-site resistance monitoring method for major thrip species, and in the selection of appropriate insecticides for their control.

총채벌레 살충제 저항성 관리 웹기반 플랫폼 구축

김소희,이영수,신용순,한세진,정인홍,이시혁 한국농약과학회 2023 농약과학회지 Vol.27 No.4

Management of pest relies mainly on the use of insecticides, which can lead to the development of insecticide resistance. In particular, thrips species are notorious for developing high levels of resistance to many types of insecticides. We aim to establish a web-based platform to provide farmers with accurate information on the insecticide resistance status of thrips and recommend optimum insecticides for efficient management. The platform has been designed with a high degree of user-friendliness, utilizing QR codes for data input, processing, and visualization in a responsive web environment. The insecticide information platform consists of an administrator page, resistance diagnostic kit result input page, and insecticide resistance map. The administrator page allows users to configure host plant, pest, and pesticide information for platform utilization. Kit results, based on the RCVpW(Residual Contact Vial plus Water) method, provide information on pesticide, and these results are displayed on a map for regional analysis. Therefore, users can make more informed pest control decisions tailored to their farms, effectively preventing the misuse of pesticides.

Development of insecticide resistance molecular maker and their application

Juil Kim,Min Kwon,Nicole Joussen,David G. Heckel 한국응용곤충학회 2016 한국응용곤충학회 학술대회논문집 Vol.2016 No.10

Worldwide, increasing numbers insecticide resistant insect is one of the main problem in this agricultural era. To manage the insecticide resistance, IRAC suggest some tips for farmers : 1. Sequence or alteration of insecticide based on MOA 2. Choosing the effective insecticide. In this point raised following question : How to distinguish the effective or non-effective insecticide. Until now, bioassay is the right answer. However that is a very time-consuming, labor-intensive, and costly process, so we were hoping that molecular based diagnosis could be alternate. It can summarized following steps : 1. Identification of insecticide resistance mechanism 2. Marker development 3. Molecular diagnosis 4. Selection of non-effective insecticide. Here we focused on the development of insecticide resistance marker. Point mutation in target site of insecticide is a good example. Up or down-regulation of specific gene and/or existence of chimeric gene is another example from Helicoverpa armigera.

Monitoring and evaluation of differential insecticide resistance profiles in the immigrant vs. indigenous populations of the small brown planthopper (Laodelphax striatellus Fallen) in Korea

Jeong, I.H.,Lee, S.W.,Choi, B.R.,Lee, S.H.,Kwon, D.H. Korean Society of Applied Entomology 2016 Journal of Asia-Pacific Entomology Vol.19 No.1

<P>The small brown planthopper (SBPH), Laodelphax striatellus Fallen, is an important pest that causes severe yield losses by transmitting plant viruses to rice. For the efficient control of SBPH in Korea, the respective resistance levels in the immigrant and indigenous populations need to be discerned. The resistance levels to 10 insecticides (three carbamates, an organophosphate, four neonicotinoids, and a phenylpyrazole) were evaluated in 21 field populations collected from either SBPH-immigrating or indigenous regions during two different seasons (spring vs. summer). Imidacloprid resistance was most widely observed in many regional populations, followed by thiamethoxam resistance. Interestingly, the resistance level to imidacloprid was significantly higher in both immigrant and late-summer-collected populations than in indigenous and early spring-collected populations, respectively [33- (p = 0.018) and 2.6-fold (p = 0.026)]. Moreover, the late summer immigrant population exhibited higher imidacloprid resistance (2.4-fold) than the early spring-collected population from the same region, suggesting that the migratory SBPH that immigrated into Korea already exhibited imidacloprid resistance traits and were further selected after inhabitation. All field populations showed little resistance to fipronil (0.1- to 0.7-fold), suggesting that it is the most effective among the tested insecticides to control field populations of SBPH. The coefficient of variation of the resistance ratio (RR) among different regional populations and the correlation co-efficient of RR among different insecticides have been suggested as supplementary parameters when determining appropriate insecticides as respective indicators for the dispersion status of resistance among SBPH populations and the possibility of cross resistance among tested insecticides. (C) 2015 Korean Society of Applied Entomology, Taiwan Entomological Society and Malaysian Plant Protection Society, Published by Elsevier B.V. All rights reserved.</P>

Monitoring and evaluation of differential insecticide resistance profiles in the immigrant vs. indigenous populations of the small brown planthopper (Laodelphax striatellus Fallen) in Korea

In-Hong Jeong,Si Woo Lee,Byeong-Ryeol Choi,Si Hyeock Lee,Deok Ho Kwon 한국응용곤충학회 2015 한국응용곤충학회 학술대회논문집 Vol.2015 No.10

The small brown planthopper (SBPH), Laodelphax striatellus Fallen, is an important pest that causes severe yield losses by transmitting plant viruses to rice. For the efficient control of SBPH in Korea, the respective resistance levels in the immigrant and indigenous populations need to be discerned. The resistance levels to 10 insecticides (three carbamates, an organophosphate, four neonicotinoids, and a phenylpyrazole) were evaluated in 21 field populations collected from either SBPH-immigrating or indigenous regions during two different seasons (early spring vs. late summer). Imidacloprid resistance was most widely observed in many regional populations, followed by thiamethoxam resistance. Interestingly, the resistance level to imidacloprid was significantly higher in both immigrant and late-summer-collected populations than in indigenous and early spring-collected populations, respectively [3.3- (p = 0.018) and 2.6-fold (p = 0.026)]. Moreover, the late summer immigrant population exhibited higher imidacloprid resistance (2.4-fold) than the early spring-collected population from the same region, suggesting that the migratory SBPH that immigrated into Korea already exhibited imidacloprid resistance traits and were further selected after inhabitation. All field populations showed little resistance to fipronil (0.1- to 0.7-fold), suggesting that it is the most effective among the tested insecticides to control field populations of SBPH. The coefficient of variation of the resistance ratio (RR) among different regional populations and the correlation coefficient of RR among different insecticides have been suggested as supplementary parameters when determining appropriate insecticides as respective indicators for the dispersion status of resistance among SBPH populations and the possibility of cross resistance among tested insecticides.