Section 5. Pyrethroid and endosulfan resistance: biology of resistant and susceptible larvae and pupae

1993 ◽  
Vol 1 ◽  
pp. 36-42 ◽  
Author(s):  
Neil W. Forrester ◽  
Matthew Cahill ◽  
Lisa J. Bird ◽  
Jacquelyn K. Layland

SummaryBoth pyrethroid and endosulfan resistant Helicoverpa armigera larvae were shown to have marginally longer development times. Pyrethroid resistant larvae were slower developers often requiring an extra moult before ultimately pupating to the same size pupa as susceptibles. There were no differences between pyrethroid resistant and susceptible pupal development times (male or female). Laboratory and field competition studies could demonstrate no selective advantage for either pyrethroid resistant or susceptible larvae or prepupae. Thus it would seem that the slightly longer larval development times do not manifest as significant biological deficits. This helps explain the gradually deteriorating pyrethroid resistance situation documented during evaluation of the Australian insecticide resistance management (IRM) strategy. There was no evidence of the selection of fitness modifiers (co-adaptation) to overcome the slower development of either pyrethroid or endosulfan resistant larvae. Endosulfan fitness disadvantages were not sufficiently researched in this study to discount the possibility of a fitness deficit contributing to the much more successful management of endosulfan resistance.

1993 ◽  
Vol 1 ◽  
pp. 28-35 ◽  
Author(s):  
Neil W. Forrester ◽  
Matthew Cahill ◽  
Lisa J. Bird ◽  
Jacquelyn K. Layland

SummaryResistance to endosulfan and pyrethroids in Helicoverpa armigera in Australia was shown to be due to multiple rather than cross resistance. The independence of the endosulfan and pyrethroid resistance mechanisms vindicates the sequential use of these two groups in Stages I and II of the insecticide resistance management strategy, respectively. Within the cyclodienes, greatest resistance occurred to dieldrin with lower order cross resistance to endosulfan and endrin. Male and female moths expressed cyclodiene resistance equally.


Author(s):  
Neil W. Forrester ◽  
Matthew Cahill ◽  
Lisa J. Bird ◽  
Jacquelyn K. Layland

SummaryIn response to field pyrethroid failures against Helicoverpa armigera (Hübner) in early 1983, an insecticide resistance management (IRM) strategy was introduced for insect control in summer crops in eastern Australia. The aims of this strategy were to contain the pyrethroid resistance problem, to prevent re-selection of historical endosulfan resistance (both curative IRM) and to avoid any future problems with organophosphate/carbamate resistance (preventative IRM). An alternation strategy was adopted which was based on the rotation of unrelated chemical groups on a per generation basis, along with a strong recommendation for the use of ovicidal mixtures. These chemical countermeasures were then integrated with other non-chemical control methods (biological and cultural) into a workable integrated pest management programme. The restrictions were applied to all Helicoverpa armigera susceptible crops (including cereals, oilseeds, grain legumes, tomatoes, tobacco and cotton) and even to other co-incident pest species. From its inception, compliance with the voluntary strategy has been exceptional.


2021 ◽  
Vol 21 (3) ◽  
pp. 1124-1140
Author(s):  
Mohd Rohaizat Hassan ◽  
Noor Atika Azit ◽  
Suhaiza Mohd Fadzil ◽  
Siti Rasidah Abd Ghani ◽  
Norfazilah Ahmad ◽  
...  

Background: The insecticides used widely has led to resistance in the vector and impose a challenge to vector control op- eration. Objectives: This review aims to analyse the distribution of insecticide resistance of dengue vectors in South East Asia and to describe the mechanism of insecticide resistance. Methods: Literature search for articles published on 2015 to 2019 from PubMed, Scopus and ProQuest was performed. Total of 37 studies included in the final review from the initial 420 studies. Results: Pyrethroid resistance was concentrated on the west coast of Peninsular Malaysia and Northern Thailand and scat- tered at Java Island, Indonesia while organophosphate resistance was seen across the Java Island (Indonesia), West Sumatera and North Peninsular Malaysia. Organochlorine resistance was seen in Sabah, Malaysia and scattered distribution in Nusa Tenggara, Indonesia. V1016G, S989P, F1269C gene mutation in Aedes Aegypti were associated with Pyrethroid resistance in Singapore and Indonesia. In Malaysia, over-expressed with monooxygenase P450 genes (CYP9J27, CYP6CB1, CYP9J26 and CYP9M4) Glutathione S-transferases, carboxylesterases commonly associated with pyrethroids resistance in Aedes Aegypti and CYP612 overexpressed in Aedes Albopictus. The genetic mutation in A302S in Aedes Albopictus was associated with organochlorine resistance in Malaysia. Conclusions: Rotation of insecticide, integration with synergist and routine assessment of resistance profile are recom- mended strategies in insecticide resistance management. Keywords: Insecticide resistance; vector management; Aedes; pyrethroid; mortality.


2020 ◽  
Vol 5 ◽  
pp. 171
Author(s):  
Diane Leslie Nkahe ◽  
Edmond Kopya ◽  
Borel Djiappi-Tchamen ◽  
Wilson Toussile ◽  
Nadege Sonhafouo-Chiana ◽  
...  

Background: Pyrethroid resistance is rapidly expanding in An. gambiae s.l. populations across Sub-Saharan Africa. Yet there is still not enough information on the fitness cost of insecticide resistance . In the present study, the fitness cost of insecticide resistance on Anopheles coluzzii population from the city of Yaoundé was investigated.  Methods: A resistant An. coluzzii colony was established from field collected mosquitoes resistant to both DDT and pyrethroid and selected for 12 generations with deltamethrin 0.05%. The Ngousso laboratory susceptible strain was used as control. A total of 100 females of each strain were blood fed and allowed for individual eggs laying, and then different life traits parameters such as fecundity, fertility, larval development time, emergence rate and longevity were measured. The TaqMan assay was used to screen for the presence of the L1014F and L1014S kdr mutations. Results:  Field collected mosquitoes from the F0 generation had a mortality rate of 2.05% for DDT, 34.16% for permethrin and 50.23% for deltamethrin. The mortality rate of the F12 generation was 30.48% for deltamethrin, 1.25% for permethrin  and 0% for DDT. The number of eggs laid per female was lower in the resistant colony compared to the susceptible (p <0.0001). Insecticide resistant larvae were found with a significantly long larval development time (10.61±0.33 days) compare to susceptible (7.57±0.35 days). The number of emerging females was significantly high in the susceptible group compared to the resistant . The adults lifespan was also significantly high for susceptible (21.73±1.19 days) compared to resistant (14.63±0.68 days). Only the L1014F-kdr allele was detected in resistant population.. Conclusion: The study suggests that pyrethroid resistance is likely associated with a high fitness cost on An.coluzzii populations. The addition of new tools targeting specifically larval stages could improve malaria vectors control and insecticide resistance management.


1993 ◽  
Vol 1 ◽  
pp. 21-27
Author(s):  
Neil W. Forrester ◽  
Matthew Cahill ◽  
Lisa J. Bird ◽  
Jacquelyn K. Layland

SummaryThe classical resistance monitoring technique using full bioassay lines on laboratory reared F1 progeny of field material was compared to the previously described discriminating dose technique on field collected individuals. The Via tolerance curve analysis of the F1 data clearly indicated the predominance of the oxidative metabolic pyrethroid resistance mechanism from the 1984/85 season onwards. There appears to have been an abrupt change in the relative importance of field resistance mechanisms following the introduction of the insecticide resistance management (IRM) strategy in 1983/84. The strategy seems to have favoured the selection of the more amenable oxidative resistance mechanism over the intractable nerve insensitivity mechanism. The Beeman-Nanis analysis was applied to attempt to identify the relative importance of the various field resistance genes. However, it proved of little value in this study as one of the key assumptions underlying the analysis (full genetic dominance) was not satisfied.


2011 ◽  
Vol 101 (4) ◽  
pp. 435-441 ◽  
Author(s):  
K.A. Polson ◽  
S.C. Rawlins ◽  
W.G. Brogdon ◽  
D.D. Chadee

AbstractInsecticide resistance is an important factor in the effectiveness of Aedes aegypti control and the related spread of dengue. The objectives of this study were to investigate the status of the organochlorine dichlorodiphenyltrichloroethane (DDT) and pyrethroid (permethrin and deltamethrin) resistance in Trinidad and Tobago populations of Ae. aegypti and the underlying biochemical mechanisms. Nine populations of Ae. aegypti larvae from Trinidad and Tobago were assayed to DDT and PYs using the Centers for Disease Control and Prevention (CDC) time-mortality-based bioassay method. A diagnostic dosage (DD) was established for each insecticide using the CAREC reference susceptible Ae. aegypti strain and a resistance threshold (RT), time in which 98–100% mortality was observed in the CAREC strain, was calculated for each insecticide. Mosquitoes which survived the DD and RT were considered as resistant, and the resistance status of each population was categorised based on the WHO criteria with mortality <80% indicative of resistance. Biochemical assays were conducted to determine the activities of α and β esterases, mixed function oxidases (MFO) and glutathione-S-transferases (GST) enzymes which are involved in resistance of mosquitoes to DDT and PYs. Enzymatic activity levels in each population were compared with those obtained for the CAREC susceptible strain, and significant differences were determined by Kruskal-Wallis and Tukey's non-parametric tests (P<0.05). The established DDs were 0.01 mg l−1, 0.2 mg l−1 and 1.0 mg l−1 for deltamethrin, permethrin and DDT, respectively; and the RTs for deltamethrin, permethrin and DDT were 30, 75 and 120 min, respectively. All Ae. aegypti populations were resistant to DDT (<80% mortality); two strains were incipiently resistant to deltamethrin and three to permethrin (80–98% mortality). Biochemical assays revealed elevated levels of α-esterase and MFO enzymes in all Ae. aegypti populations. All, except three populations, showed increased levels of β-esterases; and all populations, except Curepe, demonstrated elevated GST levels.Metabolic detoxification of enzymes is correlated with the manifestation of DDT and PY resistance in Trinidad and Tobago populations of Ae. aegypti. The presence of this resistance also suggests that knock down (kdr)-type resistance may be involved, hence the need for further investigations. This information can contribute to the development of an insecticide resistance surveillance programme and improvement of resistance management strategies aimed at combatting the spread of dengue in Trinidad and Tobago.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Henk van den Berg ◽  
Haroldo Sergio da Silva Bezerra ◽  
Samira Al-Eryani ◽  
Emmanuel Chanda ◽  
Bhupender N. Nagpal ◽  
...  

AbstractInsecticides have played a major role in the prevention, control, and elimination of vector-borne diseases, but insecticide resistance threatens the efficacy of available vector control tools. A global survey was conducted to investigate vector control insecticide use from 2010 to 2019. Out of 140 countries selected as sample for the study, 87 countries responded. Also, data on ex-factory deliveries of insecticide-treated nets (ITNs) were analyzed. Insecticide operational use was highest for control of malaria, followed by dengue, leishmaniasis and Chagas disease. Vector control relied on few insecticide classes with pyrethroids the most used overall. Results indicated that IRS programs have been slow to react to detection of pyrethroid resistance, while proactive resistance management using insecticides with unrelated modes of action was generally weak. The intensive use of recently introduced insecticide products raised concern about product stewardship regarding the preservation of insecticide susceptibility in vector populations. Resistance management was weakest for control of dengue, leishmaniasis or Chagas disease. Therefore, it will be vital that vector control programs coordinate on insecticide procurement, planning, implementation, resistance monitoring, and capacity building. Moreover, increased consideration should be given to alternative vector control tools that prevent the development of insecticide resistance.


Insects ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 826
Author(s):  
Natalie Lissenden ◽  
Mara Kont ◽  
John Essandoh ◽  
Hanafy Ismail ◽  
Thomas Churcher ◽  
...  

Pyrethroid resistance is widespread in malaria vectors. However, differential mortality in discriminating dose assays to different pyrethroids is often observed in wild populations. When this occurs, it is unclear if this differential mortality should be interpreted as an indication of differential levels of susceptibility within the pyrethroid class, and if so, if countries should consider selecting one specific pyrethroid for programmatic use over another. A review of evidence from molecular studies, resistance testing with laboratory colonies and wild populations, and mosquito behavioural assays were conducted to answer these questions. Evidence suggested that in areas where pyrethroid resistance exists, different results in insecticide susceptibility assays with specific pyrethroids currently in common use (deltamethrin, permethrin, α-cypermethrin, and λ-cyhalothrin) are not necessarily indicative of an operationally relevant difference in potential performance. Consequently, it is not advisable to use rotation between these pyrethroids as an insecticide-resistance management strategy. Less commonly used pyrethroids (bifenthrin and etofenprox) may have sufficiently different modes of action, though further work is needed to examine how this may apply to insecticide resistance management.


2020 ◽  
pp. 194-198
Author(s):  
Levchenko ◽  
Silivanova ◽  
Shumilova

New knowledge about resistance and cross-resistance to insecticides of different chemical classes in insects is crucial for correct and effective pest management. This paper reports changes in the susceptibility to insecticides of different chemical classes in the first generations of houseflies Musca domestica L. when they were selected with fipronil. The selection of M. domestica was carried out by feeding adult insects with sugar containing fipronil in a dose that causes the 40–60% mortality of insects. The susceptibility of adults and larvae to insecticides was evaluated by the resistance ratio (RR). In the fipronil-selected strain of M. domestica, the susceptibility to fipronil was unchanged in adults in 3–5 generations and increased in larvae in the fifth generation (RR = 0.5). The susceptibility to deltamethrin decreased in adults of the fourth generation and in larvae of the fifth generation, and the RR was 4.5 and 4.3, respectively, that may suggest the development of cross-resistance in the future. The susceptibility to chlorfenapyr was reduced in adults of fipronil-selected flies of the fourth generation (RR = 1.9). The susceptibility to ivermectin increased in adults of fipronil-selected flies (RR = 0.67) and in larvae of the fifth generation (RR = 0.5). The susceptibility to acetamiprid in the fipronil-selected strain and the laboratory (unselected) strain of M. domestica did not differ. The results are useful for the development of insecticide resistance management programs.


2020 ◽  
Vol 287 (1927) ◽  
pp. 20200838 ◽  
Author(s):  
George-Rafael Samantsidis ◽  
Rafaela Panteleri ◽  
Shane Denecke ◽  
Stella Kounadi ◽  
Iason Christou ◽  
...  

The putative synergistic action of target-site mutations and enhanced detoxification in pyrethroid resistance in insects has been hypothesized as a major evolutionary mechanism responsible for dramatic consequences in malaria incidence and crop production. Combining genetic transformation and CRISPR/Cas9 genome modification, we generated transgenic Drosophila lines expressing pyrethroid metabolizing P450 enzymes in a genetic background along with engineered mutations in the voltage-gated sodium channel ( para ) known to confer target-site resistance. Genotypes expressing the yellow fever mosquito Aedes aegypti Cyp9J28 while also bearing the para V1016G mutation displayed substantially greater resistance ratio (RR) against deltamethrin than the product of each individual mechanism (RR combined : 19.85 > RR Cyp9J28 : 1.77 × RR V1016G : 3.00). Genotypes expressing Brassicogethes aeneus pollen beetle Cyp6BQ23 and also bearing the para L1014F ( kdr ) mutation, displayed an almost multiplicative RR (RR combined : 75.19 ≥ RR Cyp6BQ23 : 5.74 × RR L1014F : 12.74). Reduced pyrethroid affinity at the target site, delaying saturation while simultaneously extending the duration of P450-driven detoxification, is proposed as a possible underlying mechanism. Combinations of target site and P450 resistance loci might be unfavourable in field populations in the absence of insecticide selection, as they exert some fitness disadvantage in development time and fecundity. These are major considerations from the insecticide resistance management viewpoint in both public health and agriculture.


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