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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.
... 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 control has been largely studied (Grafius, 1995(Grafius, , 1997Wustman and Carnegie, 2000;Zabel et al., 2002;Stankovik et al., 2004;Alyokhin et al., 2008;Grafius and Douches, 2008;Alyokhin, 2009;Sladam et al., 2012;Szendrei et al., 2012;Piiroinen et al., 2014;Clements et al., 2016). Although insecticides are effective, resistance has been an issue in many populations (Casagrande, 1987;Kennedy and Farrar, 1987;Helm et al., 1990;Grapputo et al., 2005;Alyokhin et al., 2006Alyokhin et al., , 2008Szendrei et al., 2012;Kaplanoglu et al., 2017;Clements et al., 2018;Crossley et al., 2018), while other populations have largely remained susceptible to insecticides (Haegele and Wakeland, 1932;Johnston and Sandvol, 1986;Olson et al., 2000;Alyokhin et al., 2015;Crossley et al., 2018;Dively et al., 2020). ...
Developing plant germplasm that contains genetic resistance to insect pests is a valuable component of integrated pest management programs. In the last several decades, numerous attempts have been made to identify genetic sources of resistance to Colorado potato beetle Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae). This review focuses on compiling information regarding general L. decemlineata biology, ecology, and management focusing on discussing biochemical and morphological potato (Solanum tuberosum L.) plant traits that might be responsible for providing resistance; the review ends discussing past efforts to identify genetic material and highlights promising new strategies that may improve the efficiency of evaluation and selection of resistant material. Measurement strategies, that begin with field screening of segregating populations or wild germplasm to narrow research focus can be useful. Identifying particularly resistant or susceptible germplasm, will help researchers focus on studying the mechanisms of resistance in much greater detail which will help the development of long-term sustainable management program.
... However, these strategies are predominantly focused on insecticides (Forgash, 1985;Grafius and Douches, 2008;Wimer, 2013) and CPB has been credited with being largely responsible for the growth of the modern insecticide industry (Gauthier et al., 1981). CPB has currently developed resistance to 56 different compounds belonging to 13 major insecticide groups (Grafius, 1995;Grafius, 1997;Alyokhin et al., 2007;Alyokhin et al., 2008;Sladan et al., 2012;Szendrei et al., 2012;Scott et al., 2015;APRD, 2020;Favell et al., 2020). Hence, the combined usage of chemical pesticides with other alternative methods is becoming increasingly important for both the pesticide industry and potato farmers to overcome control failures (Kroschel et al., 2020). ...
The Colorado potato beetle (CPB), Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), is considered as one of the most important pests of potato plants. Control of CPB is mainly based on chemical insecticides. However, control failure is often reported because of the rapid resistance development ability of CPB; therefore, there is an urgent need for integrated control methods. In this study, we evaluated the combined usage of insecticides chlorantraniliprole, spinosad, and spinetoram, which are registered for CPB control, with the entomopathogenic nematode Steinernema feltiae (Rhabditida: Steinernematidae).
In addition, the efficacy of S. feltiae on a chlorantraniliprole-resistant CPB population exposed to synergistic chemicals PBO (Piperonyl butoxide), DEM (Diethyl maleate) and DEF (S,S,S-tributylphorotrithioate) inhibiting certain detoxification enzyme groups was determined. The tested insecticides showed no adverse effect on the survival and infectivity of S. feltiae and the isolate was considered compatible with integrated CPB control. This study also showed that pre-treatment with synergistic chemicals (particularly PBO and DEM) increased the efficacy of S. feltiae against CPB. To our knowledge, this is the first study determining the usage of entomopathogenic nematode+synergist combination. Therefore, further studies on the potential use of synergistic chemicals in combination with entomopathogenic nematodes should be performed under both laboratory and field conditions.
... Even though the use of insecticides resulted in a drastic reduction of CPB populations, resistance development against the active substances resulted. It is now well documented that CPB have developed resistance to most registered insecticides [18][19][20][21][22]. Currently, CPB has developed resistance to 56 different compounds ( Figure 2) belonging to all major insecticide classes [23]. ...
Colorado potato beetle, CPB (Leptinotarsa decemlineata Say), is one of the most important pests of the potato globally. Larvae and adults can cause complete defoliation of potato plant leaves and can lead to a large yield loss. The insect has been successfully suppressed by insecticides; however, over time, has developed resistance to insecticides from various chemical groups, and its once successful control has diminished. The number of available active chemical control substances is decreasing with the process of testing, and registering new products on the market are time-consuming and expensive, with the possibility of resistance ever present. All of these concerns have led to the search for new methods to control CPB and efficient tools to assist with the detection of resistant variants and monitoring of resistant populations. Current strategies that may aid in slowing resistance include gene silencing by RNA interference (RNAi). RNAi, besides providing an efficient tool for gene functional studies, represents a safe, efficient, and eco-friendly strategy for CPB control. Genetically modified (GM) crops that produce the toxins of Bacillus thuringiensis (Bt) have many advantages over agro-technical, mechanical, biological, and chemical measures. However, pest resistance that may occur and public acceptance of GM modified food crops are the main problems associated with Bt crops. Recent developments in the speed, cost, and accuracy of next generation sequencing are revolutionizing the discovery of single nucleotide polymorphisms (SNPs) and field of population genomics. There is a need for effective resistance monitoring programs that are capable of the early detection of resistance and successful implementation of integrated resistance management (IRM). The main focus of this review is on new technologies for CPB control (RNAi) and tools (SNPs) for detection of resistant CPB populations.
... Although neonicotinoid resistance has not been documented in the PNW, Colorado potato beetle populations in eastern North America and southern Europe rapidly developed resistance soon after the introduction of neonicotinoids (Olson et al., 2000;Sladan et al., 2012;Zhao et al., 2000). In 1995, imidacloprid became the first neonicotinoid registered for use against Colorado potato beetle in the United States. ...
Over the past 20 years, potato pest management in the Pacific Northwest region of the US has changed dramatically with the emergence and resurgence of new insect pests, including vectors of new, devastating plant pathogens. Among these are the beet leafhopper that vectors the recently identified Beet leafhopper-transmitted virescence agent, aphids that vector new necrotic strains of Potato virus Y, and the potato tuberworm. However, the most important emerging pest is the potato psyllid because of its ability to vector “Candidatus Liberibacter solanacearum”, the causal agent of zebra chip disease. Pest management in the Pacific Northwest has traditionally relied on insecticides, but the risk of zebra chip has disrupted pest management programs by dramatically escalating the use of insecticides. Here, the status of pest management in Pacific Northwest is reviewed along with future research and extension needs that would allow growers to maintain economically viable and sustainable potato production.
Background:
Global climate change, will result in an increasingly arid weather which will impose a significant impact on agriculture. The occurrence dynamics of plants, phytophagous insects and their natural enemies under drought have attracted much attention. The consequences could be useful for controlling insect herbivores. Leptinotarsa decemlineata (Say) is one of the most important potato pests, which causes serious damage to potato production. Arma chinensis (Fallou) is a parasitoid of L. decemlineata. However, how drought will affect the titrophic interactions among potato and these insects are unknown.
Results:
In this experiment, L. decemlineata and A. chinensis were subsequently released on potato plants, under water stress treatments. Thereafter, plant height, stem diameter and yield of potato, the 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 exerted a significant impact on the pre-oviposition period, oviposition days, fecundity and life table parameters of L. decemlineata (P<0.05). Moreover, drought significantly reduced the longevity (P<0.05) and the survival rate of A. chinensis adults. The longevity of adult A. chinensis was only 29.00±3.00 d and the harvest rate of L. decemlineata adults was only 1.42±0.07% under drought treatment.
Conclusion:
In this experiment, we evaluated the bottom-up effects of drought on tritrophic interactions involving potato, L. decemlineata and A. chinensis, and discuss the implications of the findings for the integrated pest management programs involving the pest. Future promising research directions are then proposed.
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