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Resistance of Colorado potato beetle (Coleoptera: Chrysomelidae) to neonicotinoids, pyrethroids and nereistoxins in Serbia
Abstract and Figures
Colorado potato beetle (CPB, Leptinotarsa decemlineata Say) resistance is one of the limiting factors in potato production in some regions of Serbia. Imidacloprid is first introduced neonicotinoid insecticide in use for effective CPB control. Introduction of such insecticides with novel mode of action and physicochemical properties, demands investigations on resistance risks and management tactics. Primary candidates for cross resistance are insecticides acting on same target sites (such as bensultap, with CPB resistance reported), although other cross resistance patterns between apparently unrelated insecticides are not uncommon. Results of the investigations presented in this paper refers to the resistance of CPB adults to 3 insecticides-imidacloprid, bensultap and cypermethrin, most commonly used by farmers in recent years. First generation adults from nine field populations in first and four representative populations in second year of investigation were tested by topical application. Resistance ratios for bensultap ranged from 1.0 to 645.3 (LD 50 from 0.04 – 25.81 μg/insect). Cypermethrin resistance ratios ranged from 1.0 to 60.0 (LD50 from 0.02 – 2.05 μg/insect). Imidacloprid
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... Known mechanisms of CPB resistance to insecticides include mutations in genes encoding target receptors or enzymes (e.g., VGSCs, AChE), enhanced metabolism involving esterases, carboxylesterases, and monooxygenases, as well as reduced insecticide penetration and increased excretion (Figure 3) [67]. Resistance mechanisms may be highly diverse, even within a relatively narrow geographical area and between the life stages of the beetle [66,81]. The first recorded case of the resistance of this pest to a synthetic organic compound was the failure of DDT in 1952. ...
... The Colorado potato beetle's resistance to azinphosmethyl (an organophosphate) and carbofuran (a carbamate) were observed as early as the late 1970s [5]. This resistance is associated with a point mutation in AChE, a substitution of adenine with guanine at Resistance mechanisms may be highly diverse, even within a relatively narrow geographical area and between the life stages of the beetle [66,81]. The first recorded case of the resistance of this pest to a synthetic organic compound was the failure of DDT in 1952. ...
... The kdr mutation shows an incompletely recessive inheritance in the CPB population [78,82]. In Europe, pyrethroid resistance due to kdr was detected in CPB field populations in Bulgaria, Czech Republic, Germany, and Serbia [78,81,86,94,95]. In addition to L1014F, two more target site mutations (T929I, T929N) were described in the sodium channel, which confer a super-kdr-like phenotype in the Bulgarian CPB population (Figure 4) [95]. ...
Colorado potato beetle (Leptinotarsa decemlineata, CPB) is considered one of the most persistent crop pests because it is highly adaptable and can rapidly develop insecticide resistance. Nowadays, this beetle is resistant to over 54 different insecticides. In the absence of competitive alternatives, the answer of farmers to the high degree of pest adaptability is to increase the number of pesticide treatments or apply chemicals with different modes of action. Such a strategy increases the risk of intoxication in non-target organisms and leads to environmental pollution, augmenting the carbon footprint. Furthermore, these strategies are also unsustainable and inefficient for pest management in the long-term. The time has thus come to reform existing agriculture practices, for which the implementation of an integrated pest management strategy would be a more feasible tool. Applying a sustainable pest management strategy is indispensable for a better understanding of the status and mechanisms of insecticide resistance. Effective pest management requires monitoring the resistance of pests and developing a well-programmed pesticide treatment to simultaneously reduce the insecticide selection pressure and environmental pollution. In this context, here we present a review on the difficulties of potato pest control using as a case study the resistance of CPB to pyrethroids.
... Colorado potato beetle (Leptinotarsa decemlineata Say) -CPB is a major and the most destructive pest in potato production worldwide (Hare 1990;Alyokhin et al. 2006Alyokhin et al. , 2008Alyokhin et al. , 2013Jiang et al. 2010;Stanković et al. 2004aStanković et al. , 2012. Current CPB management and control practices include biological control, cultural practices, IPM Gökçe et al. 2006;Kostic et al. 2002Kostic et al. , 2003Kostic et al. , 2007Kostic et al. , 2008Kostic et al. , 2012Trdan et al. 2009;Popovic et al. 2013;Stankovic et al. 2020;Lazarević et al. 2020), but still the most efficient are chemical (pesticide) treatments (Zabel et al. 2000;Igrc Barčić et al. 2006;Boiteau 2010). ...
... Current CPB management and control practices include biological control, cultural practices, IPM Gökçe et al. 2006;Kostic et al. 2002Kostic et al. , 2003Kostic et al. , 2007Kostic et al. , 2008Kostic et al. , 2012Trdan et al. 2009;Popovic et al. 2013;Stankovic et al. 2020;Lazarević et al. 2020), but still the most efficient are chemical (pesticide) treatments (Zabel et al. 2000;Igrc Barčić et al. 2006;Boiteau 2010). Simultaneously with the development of control measures, producers are facing rapid resistance development to all major groups of insecticides (Zhao et al. 2000;Stanković et al. 2003;Alyokhin et al. 2007;Wȩgorek et al. 2011;Stanković et al., 2012;Szendrei et al. 2012;Zhou et al. 2012), including organophosphates and carbamates (Stanković et al. 2004b;Kostic et al. 2015;Zabel et al. 2017). Insecticide resistance presence and level is measurable (Miyata 1983;Bishop and Grafius 1991;Stanković et al. 2004a) and that is important tool for insecticide resistance monitoring as part of insecticide resistance management (IRM) strategies and practices (IRAC 2022). ...
Colorado potato beetle (CPB) is an extraordinary example of pest resistance to insecticides. It is proved that increased activity of CPB’s ALiE / carboxylesterase is closely related to resistance to organophosphate insecticides. ALiE activity of different populations was tested, using spectrophotometry. The frequencies of ALiE activity of individual larvae were similar to the binomial distribution. For more resistant populations to organophosphates, the whole graph is shifted to the area with higher enzyme activity. Consequently, individuals with lower ALiE activity disappear from the population while individuals with higher activity appear more frequently. The analysis of single larvae ALiE activity showed a fairly high homogeneity of the examined populations, except for the population Kaona. Examination of single insect ALiE activity is viable and provides insight into the population, which is important for further genetic testing.
... By 2009, 95% of the populations tested from the northeastern and midwestern United States were resistant to imidacloprid [12]. To date, resistance to neonicotinoid insecticides has been reported in China [13], Serbia [14], and Canada [15]. CPB populations resistant to acetamiprid in Czechia were first observed by farmers in 2010, while insecticides based on thiacloprid or thiamethoxam were still efficient (unpublished data). ...
The Colorado potato beetle (CPB; Leptinotarsa decemlineata) is an important potato pest with known resistance to pyrethroids and organophosphates in Czechia. Decreased efficacy of neonicotinoids has been observed in last decade. After the restriction of using chlorpyrifos, thiacloprid and thiamethoxam by EU regulation, growers seek for information about the resistance of CPB to used insecticides and recommended antiresistant strategies. The development of CPB resistance to selected insecticides was evaluated in bioassays in 69 local populations from Czechia in 2017–2022 and in 2007–2022 in small plot experiments in Zabcice in South Moravia. The mortality in each subpopulation in the bioassays was evaluated at the field-recommended rates of insecticides to estimate the 50% and 90% lethal concentrations (LC50 and LC90, respectively). High levels of CPB resistance to lambda-cyhalothrin and chlorpyrifos were demonstrated throughout Czechia, without significant changes between years and regions. The average mortality after application of the field-recommended rate of lambda-cyhalothrin was influenced by temperature before larvae were sampled for bioassays and decreased with increasing temperature in June. Downwards trends in the LC90 values of chlorpyrifos and the average mortality after application of the field-recommended rate of acetamiprid in the bioassay were recorded over a 6-year period. The baseline LC50 value (with 95% confidence limit) of 0.04 mg/L of chlorantraniliprole was established for Czech populations of CPBs for the purpose of resistance monitoring in the next years. Widespread resistance to pyrethroids, organophosphates and neonicotinoids was demonstrated, and changes in anti-resistant strategies to control CPBs were discussed.
... It was estimated that about 40-50 cm 2 of potato leaves are consumed by a single beetle during its larval stage [77]. This pest has remarkable adaptability to variable climates and environmental stresses and undergoes prompt evolutionary change, which strengthens its ability to rapidly evolve resistance to almost all registered insecticides or their active ingredients [78][79][80][81][82]. Considering that plants and pests co-evolve, host-plant resistance is one of the best solutions for controlling the CPB. ...
cyclodextrin (β-CD) is a good host for the encapsulation of fennel and basil essential oils (FEO and BEO, respectively) and the formation of inclusion complexes (ICs) using the co-precipitation method. According to the results of the GC/MS analysis conducted in this study, monoterpenes and monoterpenoids were the dominant chemical groups in total FEO, while in BEO, these two groups occurred along with sesquiterpenes and sesquiterpenoids. The presence of dominant compounds from both EOs was validated using the FT-IR spectra of ICs, which indicated successful complexation. Analyses conducted using SPME/GC-MS showed the continuous emission of vola-tiles over 24 h from both ICs. Under SEM, particles of both ICs appeared to have a rectangular or rhomboid morphology and few aggregates. The insecticidal properties of EOs and ICs with β-CD were tested on the Colorado potato beetle (CPB) as a model pest. The inclusion complex of β-CD with FEO altered the developmental dynamic and body mass of the CPB. The initial increase in the proteolytic activity of CPB larvae fed with potato plants sprayed with ICs was not maintained for long, and the proteolytic efficacy of treated larvae remained in line with that of the control larvae. Future investigations will focus on manipulating the volume of EOs used and the treatment duration for optimal efficacy and potential application.
... Because of its excellent systemic properties, it can be used as seed dressing, as soil and foliar treatment in different crops including rice, maize, potatoes, cotton, cereals, sugar beets and vegetables. In industry imidacloprid is considered to be a pesticide of relatively low toxicity, it has been found to be very toxic to the non-target insects such as bees [7,8]. Sorption of imidacloprid increases with increasing soil organic carbon and pesticide concentration. ...
Pesticides are the chemical substances that prevent, kill, repel any pest. Repeated use of same pesticide, bulky handling or accidental release results in accumulation of pesticides residues or its metabolites in soil or water streams. The persistent nature of pesticides carries potential hazards to man and show lethal effects on living system. Imidacloprid (1-[(6-chloro-3-pyridinyl)-methyl]-N-nitro-2-imidazolidinimine), is a second-generation neonicotinoid pesticide (chloronicotinyl insectile). It is used to treat a wide range of pests on rice, maize, potatoes and vegetables. Imidacloprid has been reported as a stable compound in the environment with a half-life over 100 days. There are very few repots of imidacoprid degrading soil microorganisms. In an effort to find active microbial strains over the problem of commonly used pesticides like imidacloprid, a study was carried out. The objectives of this study were to isolate and characterize the efficient imidacoprid degrading microorganisms from the contaminated agricultural soil. The minimal salt medium (MSM) was used for testing the imidacloprid degrading ability of the isolates. They were characterized based on their morphological, cultural and biochemical characteristics. Among 20 soil isolates, bacterial isolates Bacillus spp., Azotobacter spp, Azospirillum spp. and Pseudomonas spp. showed degradation of imidacloprid after 48-72 hours of incubation. Imidacloprid was degraded by Azospirillum spp up to 500 mgL-1 and Bacillus spp., Pseudomonas species and Azotobacter species upto 200 mgL-1. Detection of presence of NO2 ̶ in the inoculated broth was the indication of imidacloprid degradation by the microorganisms. These findings suggest that these strains may be the promising organisms for bioremediation of imidacloprid contaminated soils. KEY WORDS Biodegradation, bioremediation, Imidacloprid and insecticide.
... The main potato pest, the Colorado potato beetle Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), which causes massive mechanical damage to plants, is very flexible and rapidly adapts to the active substances of plant protection products [8]. In addition, it is common to find different resistance levels among populations from different localities [9]. The arrival of neonicotinoid insecticides in 1995 brought a period of relief in areas where the beetles had developed resistance to other chemicals [10]. ...
The increasing scarcity of active substances approved for use in plant protection is reflected in the growing effort to find suitable plant protection alternatives. Products based on plant oils could provide a promising environmentally friendly solution. In previous research in laboratory conditions, the synergistic effect of neem and karanja oils on Leptinotarsa decemlineata (CPB) larvae was observed. The aim of this current study was to verify whether the synergistic effect would also be observed in field conditions. The active substances used included azadirachtin A (NeemAzal® T/S); in both a reduced dose of 10.6 g/ha and a normal dose of 26.5 g/ha (Neem1, Neem2), Pongamia pinnata oil (Rock Effect New–REN); in a reduced dose of 1987.6 g/ha, and a mixture of both reduced doses (MIX). The protective effect was expressed by a visual estimation of the damaged leaf area on the potato plant. The MIX variant was always among the least damaged variants throughout the experiments, while the control was always the most damaged variant. A synergistic effect was observed at site I in 2021 when the MIX variant was more than 10 times less damaged than the control; in other cases, it was around 3 times less damaged. Treatment with MIX provided a protective effect comparable to NeemAzal® T/S in the full dose. This mixture can therefore be used to expand the portfolio of suitable preparations against CPB larvae in potato production.
... Chemical methods have been the major means of controlling L. decemlineata in China. However large doses and high-frequency use of insecticides such as neonicotinoids, 4 pyrethroids, 5 organophosphorus, carbamate 6 and other chemicals [7][8][9] have resulted in the rapid development of insecticide resistance in L. decemlineata. In addition, extensive use of chemical pesticides has had a serious impact on the ecological environment. ...
BACKGROUND
Global climate change will result in increasingly arid weather that will have a significant impact on agriculture. The occurrence dynamics of plants, phytophagous insects and their natural enemies under drought conditions have attracted much attention. The consequences could be useful for controlling insect herbivores. Leptinotarsa decemlineata (Say) is one of the most important pests of potato, and causes serious damage to potato production. Arma chinensis (Fallou) is a parasitoid of L. decemlineata. However, how drought will affect tritrophic interactions between potato and these insects remains unknown.
RESULTS
In this experiment, L. decemlineata and A. chinensis were released onto potato plants under water stress. Thereafter, plant height, stem diameter and yield of potato, growth and reproduction of L. decemlineata, and the longevity of A. chinensis adults were periodically recorded. The results showed that drought had crucial effects on height, stem diameter and yield of potato (p < 0.05); it also had a significant impact on pre‐oviposition period, oviposition days, fecundity and life table parameters in L. decemlineata (p < 0.05). Moreover, drought significantly reduced the longevity (p < 0.05) and survival rate of A. chinensis adults. The longevity of adult A. chinensis was only 29.00 ± 3.00 days and the harvest rate of L. decemlineata adults was only 1.42% ± 0.07% under drought treatment.
CONCLUSION
In this experiment, we evaluate the bottom‐up effects of drought on tritrophic interactions involving potato, L. decemlineata and A. chinensis, and discuss the implications of the findings for integrated pest management programs involving the pest. Promising future research directions are proposed. © 2022 Society of Chemical Industry.
Potato is an important food crop. The Colorado potato beetle (CPB) is its key pest. CPBs are now resistant to several chemical pesticides, making their control more difficult. The predatory insect, Arma chinensis , is a natural enemy of other plant pests. We studied the predation of adult A. chinensis on CPB eggs and young larvae under indoor controlled conditions and its control of CPB in cages under outdoor conditions. Adult A. chinensis effectively reduces CPB egg and larva populations, and its predatory functional response aligns with Holling’s Type II model. A. chinensis adults released within outdoor cages reduced CPB populations. Based on the predation behavior of the adults of A. chinensis to CPB eggs and young larvae, A. chinensis is an efficient and potential predator.
Crop rotation is an important strategy for pest reduction. For mono-, or oligophagous pests that overwinter at a previously infested site, crop rotation means that the pests must find new host crop sites in the following year, and it is more efficient if a pest-specific distance is applied. Here, we report the development of a GIS-based tool for efficient cultivation planning using the example of the pest complex pea moth (Cydia nigricana) and grain and green peas (Pisum sativum). Monitoring data for four consecutive years (2016–2019) from 513 sites were used. Infestation of pea seeds and the distance to the previous year’s pea sites were recorded. An adjustable Python script was developed by means of infestation–distance–correlation as a pest and crop-specific minimum migration distance (MD). The output of the tool is a risk map as decision support for cultivation planning. It shows different risk buffers with distances from 1261 m to 1825 m, depending on the cultivation type. The web tool is easily adjustable to other pests and crops anywhere in the world. The tool helps to prevent damages caused by agricultural, mono-, or oligophagous insect pests and consequently reduces pesticide applications for the benefit of the environment and biodiversity.
Bt crops are the most important of the commercialised transgenic plants which were developed to combat destructive pests. Colorado potato beetle (CPB) is considered as a dangerous threat to potato production. In this study transgenic potato plants expressing cry3A gene were generated using Agrobacterium mediated transformation to combat the pest damage. Polymerase chain reaction (PCR) analysis confirmed the presence of transgenes in 40 out of 110 putative transgenic lines. One to three copies of cry3A gene were identified in selected transgenic lines using southern blot analysis. Moreover, immunostrip test confirmed the expression of Cry3A protein in the leaves of transgenic potato plants. Bioassay analysis with the first instar of CPB larvae indicated 100% mortality, significantly lower leaf damage and less insect biomass accumulation for transgenic lines (PC3-3, PC3-4, PC3-5, PC3-8 and PC3-13) in comparison to control plants. The results indicated that Cry3A protein expression could efficaciously increase the resistance to CPB in transgenic potato cv. Agria which is recommended for controlling CPB damage and to prevent its spread in potato cultivation regions. Moreover, these transgenic lines can be used as cultivar or germplasm to breed new cultivars.
The susceptibility of Colorado potato beetles (Leptinotarsa decemlineata) (CPB) from three provinces in western Canada was measured using a filter paper bioassay to substantiate the reported insecticide resistance by the beetle in Manitoba, and to compare the situation there to beetle populations from Saskatchewan and Alberta. Susceptibility of beetles was measured against five insecticides: the organophosphates, azinphos-methyl (Guthion), and methamidophos (Monitor); the pyrethroid, permethrin (Ambush); the organochlorine, endosulfan (Endosulfan); and the carbarnate, carbaryl (Sevin). All 12 populations tested from Manitoba were found to have resistance to one or more of the insecticides. All populations were classified as either having resistance or intermediate resistance to permethrin; two of the populations were classified as having resistance to azinphos-methyl and three to methamidophos. Two of four populations from Saskatchewan were classified as having intermediate resistance to azinphos-methyl and methamidophos. Intermediate resistance to permethrin was recorded in 12 of the 13 populations from Alberta, with only one being highly susceptible. Two populations showed evidence of intermediate resistance to azinphos-methyl and three to methamidophos. In all three provinces, survival rate from different egg masses within the susceptible populations ranged from 0-100%, indicating the presence of individuals with either resistance, intermediate or high susceptibility within these populations. With the expanding potato acreage in western Canada and the detection of the CPB populations with resistance to insecticides, a resistance management program must be implemented to prevent the rapid selection of resistant populations.
Repeated use of neonicotinoid insecticides has resulted in the first reported cases of Colorado potato beetle (Leptinotarsa decemlineata (Say)) resistance to imidacloprid. In the laboratory we determined susceptibility of the imidacloprid-resistant Colorado
potato beetles from a population in Southern Maine to other insecticides currently registered for use on potato. This population
was about 30-fold resistant to imidacloprid and could not be effectively controlled by its applications. Control mortality
was significantly higher for the imidacloprid-resistant larvae than for the susceptible larvae, suggesting that fitness disadvantages
may be associated with the resistance trait. Resistant larvae exhibited significantly less mortality than susceptible larvae
when exposed to cyfluthrin, carbaryl, azinphosmethyl, and methamidophos. Their susceptibility to oxamyl was also somewhat
reduced, although it did provide nearly 100% mortality at the highest concentration tested. Disulfoton was highly toxic to
the resistant larvae. Oxamyl killed about 40% of the adults in greenhouse assays with potted potato plants, altered their
feeding behavior (fewer adults up on plants), and reduced defoliation by more than 90%. Disulfoton was not lethal to adults,
but significantly suppressed their feeding. In field trials with the resistant population, oxamyl and imidacloprid + spinosad
provided the best beetle control. Novaluron had no detectable effect on beetle densities. There was little difference between
the plots treated with imidacloprid or thiamethoxam and the untreated control. Our results suggest that insecticide rotation
may be a valuable option for managing imidacloprid-resistant Colorado potato beetle populations. We also had a good consistency
between the results of the Petri dish, greenhouse, and field experiments, indicating that screening under laboratory confinement
may be useful when developing initial recommendations to potato growers in areas affected by resistance to neonicotinoids.
El uso reiterado de insecticidas neonicotinoides ha dado como resultado, en los primeros casos reportados sobre el escarabajo
de Colorado de la papa [Leptinotarsa decemlineata (Say)], resistencia al imidacloprid. En el laboratorio hemos determinado susceptibilidad de los escarabajos resistentes al
imidacloprid, a otros insecticidas registrados actualmente para su uso en papa, en una población del Sur de Maine. Esta población
fue alrededor de 30 veces más resistente al imidacloprid y no pudo ser efectivamente controlado con su aplicación. La mortalidad
en el testigo fue significativamente alta para las larvas resistentes al imidacloprid que en larvas susceptibles, sugiriendo
que este hecho puede estar asociado con la característica de resistencia. Las larvas resistentes mostraron significativamente
menos mortalidad que las susceptibles cuando estuvieron expuestas al cyfluthrin, carbaryl, azinphosmetyl y metamidophos. Su
susceptibilidad al oxamyl fue en cierta forma reducida, aunque proporcionó cerca del 100% de mortalidad a una alta concentración.
El disulfoton fue altamente tóxico a las larvas resistentes. El oxamyl mató alrededor de un 40% de adultos en pruebas de invernadero
con plantas en maceta, alteró su hábito de alimentación (pocos adultos sobre las plantas) y redujo la defoliación por más
del 90%. El disulfoton no fue letal para adultos, pero suprimió significativamente su alimentación. En pruebas de campo con
la población resistente, oxamyl e imidacloprid + spinosad, proporcionaron el mejor control del escarabajo. Novaluron no tuvo
efecto detectable sobre la densidad del escarabajo. Hubo poca diferencia entre las parcelas tratadas con imidacloprid o thiamethoxam
y el testigo no tratado. Nuestros resultados sugieren que la rotación de insecticidas puede ser una opción valiosa para manejar
las poblaciones del escarabajo de Colorado de la papa. También hemos tenido consistencia entre los resultados de los experimentos
en placa Petri, invernadero y campo, lo cual indica que el tamizado en el laboratorio puede ser útil cuando se desarrollen
las recomendaciones iniciales para los cultivadores de papa en áreas afectadas por resistencia a neonicotinoides.
Understanding the movement of invading organisms is critical to predicting invasion dynamics. The Colorado potato beetle, Leptinotarsa decemlineata (Say), is an invasive species on multiple spatial and temporal scales, and can serve as a model for studies of invasion dynamics. It is the major insect defoliator of potato in North America, and successful management requires an understanding of CPB invasions of individual fields. Its origin, spread, and biology, especially the cycle of annual invasions of agricultural potato fields, are described. Approaches to reducing the size of colonizing populations include rotation, delay of planting, and treatments of field margins. Rotation and sub-lethal insecticide treatments can slow the establishment of invasions within fields. These approaches interact with a late season diapause switch away from reproduction to reduce the impact of CPB. The refuge approach to delaying the fixation of resistance alleles is designed to encourage alleles for susceptibility to invade treated areas. We present data from an experimental refuge crop planted adjacent to a field treated with imidacloprid, an insecticide for which there is high variation in resistance. The treated field was four times as resistant as the untreated side, and a cline in resistance was formed from the untreated to the treated portion of the field. The cline width of about 100m provides an empirical basis for designing refuges to enhance the spread of alleles for susceptibility into treated areas and prevent fixation of resistance in the summer generation.
Leptinotarsa decemlineata (Say), the Colorado potato beetle (potato beetle), is the most destructive potato pest in Serbia. Up to four pesticide treatments are necessary for its control. Insecticide resistance of the potato beetle in Serbia is well-investigated and documented, especially to organophosphates and carbamates. Toxicity of chlorpyriphos (organophosphates) and carbosulfan (carbamates) was investigated by topical application, using adults of the first generation from nine field populations. Adults of all populations possessed a certain level of resistance to both insecticides, with very low regression slopes (0.50–1.09 for chlorpyriphos and 0.57–0.85 for carbosulfan). Resistance ratios for chlorpyriphos ranged from 1.0 to 109.7 and from 1.0 to 52.8 for carbosulfan. There was no correlation between resistance to chlorpyriphos and carbosulfan. The key modes of resistance to organophosphates and carbamates are metabolism [overproduction of aliesterase (ALiE), a carboxylesterase] and altering the target site of acetylcholine esterase (AChE). Biochemical research of potato beetle resistance to organophosphates and carbamates, based on activity of ALiE and AChE, proved that the key mode of resistance to organophosphates was modification of ALiE and AChE to carbamates. Our results correspond to this research concerning the lack of correlation between resistances to these two insecticides. A certain level of resistance of the potato beetle to organophosphates and carbamates is widespread in Serbia. Different modes of resistance suggest the possibilities of control of this pest, such as choice of insecticide and insecticide rotation, wherever possible.
Insecticide susceptibility was investigated with laboratory bioassays, in the populations of the Colorado potato beetle (Leptinotarsa decemlineata Say) from four places in the Belgrade surroundings, each with a different history of insecticide applications. The testings were carried out in 1990-1995 with insecticides of different chemical classes: carbosulfan, benfuracarb, chlorpyriphos, bensultap, deltamethrine, fenvalerate, permethrin and cypermethrin. The lethal effects toward adults were determined after topical applications of the insecticides. When comparing toxicity responses, the greatest LD50 differences between the populations were established with deltamethrine. The difference was nearly 190-fold between the highest and the lowest LD50 level for this compound. Results also showed high differences for cypermethrin, fenvalerate and bensultap: 85.9, 44.9 and 38.0-fold, respectively.
In 1995, also a susceptibility check with regard to carabamates, pyrethroides and organophosphorous compounds on the populations of the L. decemlineata from five different localities in Serbia (Dobanovci, Starcevo, Vršac, Sjenica and Ivanjica) was carried out. Very irregular changes in the susceptibility level of the L. decemlineata to the investigated insecticides were detected. The population from Starcevo manifested the highest resistance to carabamates (LC-50 for carbaril was 3200,4 ppm, for carbosulfan it was 11038 ppm). The resistance factor of this population for carabamates in relation to the population from Sjenica (the one most susceptible to carabamates) is 31.331, and for carbosulfan it is 144.361. The highest resistance to pyrethroides was displayed by the population from Ivanjica (LC-50 for cypermetrine is 38,3 ppm) with a resistance factor of 48.784 in relation to the population from Dobanovci. The population from Dobanovci was the most resistant to organophosphorous compounds (LC-50 for quinalphos 23.571 ppm) with a resistance factor 113.375 in relation to the population from Sjenica.
This paper presents the results of long-term monitoring of insecticide resistance in populations of agricultural pests in Russia. Over the last 45 years, resistance developments were recorded for 36 arthropod pest species in 11 agricultural crops and pastures in relation to nearly all commonly used plant protection products. Development of group, cross and multiple resistance has been revealed in populations of many economically important pests. Toxicological and phenotypical (for Colorado potato beetle) methods have been devised to monitor the development of pesticide resistance. Based on experience over the last century, systems aimed at preventing the development of pest resistance to insecticides and acaricides are elaborated. These systems are based on resistance monitoring and using plant protection measures which minimize the toxic pressure on agroecosystems.
Field trials were conducted in 2003 and 2004 to assess the effectiveness of novaluron (Rimon 10EC), a benzoylphenyl urea chitin synthesis inhibitor, for Colorado potato beetle, Leptinotarsa decemlineata (Say), management on potato. Foliar applications of novaluron did not significantly reduce numbers of L. decemlineata adults, egg masses, or first instar larvae, but second–fourth instars were greatly suppressed. Although an application rate of 12.5 g AI ha À1 provided unsatisfactory protection, rates of 25 and 50 g AI ha À1 proved effective when applied 2 days after second instars were first observed on plants. These rates were much less effective when applied 2 days after observance of egg masses. At 50 g AI ha À1 , novaluron provided excellent, prolonged protection, whether applied twice a season, or once in alternation with imidacloprid. Defoliation was minimized, resulting in yields 3.8–5.2 times greater than those harvested from control plots. The results suggest that novaluron could be a valuable tool in future L. decemlineata management programs.
The development of insect pest management strategies for potato has long been based on the eventual replacement of insecticides
by alternative methods. This paper discusses the importance of moving away from this confrontational approach and toward the
harmonization of conventional and alternative insect control concepts. A harmonized set of control methods should speed up
progress towards a truly integrated management approach that provides both long and short term crop protection. Changing the
paradigm does not resolve all the problems. Constraints to the development and implementation of the different types of control
methods are discussed using selected examples. The harmonization concept has been discussed in general terms elsewhere but
to the best of my knowledge it is applied here for the first time specifically to potato crop protection.
El desarrollo de estrategias de manejo de insectos plaga para papa se ha basado por mucho tiempo en el eventual reemplazo
de insecticidas por métodos alternativos. Este artículo discute la importancia de alejarse de este enfoque confrontacional,
e ir hacia la armonización de los conceptos convencionales y alternativos del control de insectos. Un conjunto de métodos
de control armonizado podría acelerar el progreso hacia un enfoque de manejo integrado verdadero, que proporcione protección
al cultivo tanto a largo como a corto plazo. El cambio de paradigmas no resuelve todos los problemas. Se discuten las limitantes
para el desarrollo e implementación de los diferentes tipos de métodos de control, usando ejemplos selectos. En términos generales,
se ha discutido el concepto de armonización en otros lados, pero hasta donde yo sé, se aplica aquí por primera vez específicamente
para la protección del cultivo de papa.
KeywordsIntegrated insect management-Cultural practices-Insecticides