Geographic Monitoring of Insecticide Resistance Mutations in Native and Invasive Populations of the Fall Armyworm

Field evolved resistance to insecticides is one of the main challenges in pest control. The fall armyworm (FAW) is a lepidopteran pest species causing severe crop losses, especially corn. While native to the Americas, the presence of FAW was confirmed in West Africa in 2016. Since then, the FAW has been detected in over 70 countries covering sub-Saharan Africa, the Middle East, North Africa, South Asia, Southeast Asia, and Oceania. In this study, we tested whether this invasion was accompanied by the spread of resistance mutations from native to invasive areas. We observed that mutations causing Bt resistance at ABCC2 genes were observed only in native populations where the mutations were initially reported. Invasive populations were found to have higher gene numbers of cytochrome P450 genes than native populations and a higher proportion of multiple resistance mutations at acetylcholinesterase genes, supporting strong selective pressure for resistance against synthetic insecticides. This result explains the susceptibility to Bt insecticides and resistance to various synthetic insecticides in Chinese populations. These results highlight the necessity of regular and standardized monitoring of insecticide resistance in invasive populations using both genomic approaches and bioassay experiments.

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Genomic balancing selection is key to the invasive success of the fall armyworm

10.1101/2020.06.17.154880 ◽

2020 ◽

Author(s):

Sudeeptha Yainna ◽

Wee Tek Tay ◽

Estelle Fiteni ◽

Fabrice Legeai ◽

Anne-Laure Clamens ◽

...

Keyword(s):

West Africa ◽

Population Genomics ◽

Balancing Selection ◽

Fall Armyworm ◽

Western Hemisphere ◽

Sub Saharan Africa ◽

Old World ◽

Native Populations ◽

Mild Reduction ◽

Sub Saharan

AbstractA successful biological invasion involves survival in a newly occupied environment. If a population bottleneck occurs during an invasion, the resulting depletion of genetic variants could cause increased inbreeding depression and decreased adaptive potential, which may result in a fitness reduction. How invasive populations survive in the newly occupied environment despite reduced heterozygosity and how, in many cases, they maintain moderate levels of heterozygosity are still contentious issues1. The Fall armyworm (FAW; Lepidoptera: Spodoptera frugiperda), a polyphagous pest, is native to the Western hemisphere. Its invasion in the Old World was first reported from West Africa in early 2016, and in less than four years, it swept sub-Saharan Africa and Asia, finally reaching Australia. We used population genomics approaches to investigate the factors that may explain the invasive success of the FAW. Here we show that genomic balancing selection played a key role in invasive success by restoring heterozygosity before the global invasion. We observe a drastic loss of mitochondrial polymorphism in invasive populations, whereas nuclear heterozygosity exhibits a mild reduction. The population from Benin in West Africa has the lowest length of linkage disequilibrium amongst all invasive and native populations despite its reduced population size. This result indicates that balancing selection increased heterozygosity by facilitating the admixture of invasive populations from distinct origins and that, once heterozygosity was sufficiently high, FAW started spreading globally in the Old World. As comparable heterozygosity levels between invasive and native populations are commonly observed1, we postulate that the restoration of heterozygosity through balancing selection could be widespread among successful cases of biological invasions.

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The Spread of Fall Armyworm (faw) Spodotera Frugiperda

Outlooks on Pest Management ◽

10.1564/v29_oct_07 ◽

2018 ◽

Vol 29 (5) ◽

pp. 213-214 ◽

Cited By ~ 3

Author(s):

Graham Matthews

Keyword(s):

Fall Armyworm ◽

Sub Saharan Africa ◽

Sub Saharan ◽

Army Worm

The author introduces the next three articles on the invasion of Fall Army Worm into Sub-Saharan Africa and Asia describing how the pest spreads, the damage it causes and approaches to its control.

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Purchases of psychotropic drugs among the migrant population in Finland: a nationwide register-based cohort study

European Journal of Public Health ◽

10.1093/eurpub/ckaa117 ◽

2020 ◽

Vol 30 (6) ◽

pp. 1152-1157

Author(s):

Venla Lehti ◽

Jaana Suvisaari ◽

Mika Gissler ◽

Niina Markkula

Keyword(s):

Psychotropic Drugs ◽

Service Use ◽

Cox Regression ◽

Sub Saharan Africa ◽

Service Needs ◽

Foreign Born ◽

Cox Regression Analysis ◽

Migrant Populations ◽

Native Populations ◽

Sub Saharan

Abstract Background Migrant populations may have different mental health service needs when compared with native populations. One indicator of service use is the use of psychotropic medication. The aim of this study was to compare the purchases of psychotropic drugs among different migrant populations with the native population in Finland. Methods Foreign-born participants (n = 184 805) and their Finnish-born controls (n = 185 183) were identified from the Finnish Central Population Register. Information on their purchases of psychotropic drugs in 2011–15 was collected from the National Prescription Register. A washout period of 2009–10 was used to define incident purchases. Cox regression analysis was the statistical method used. Results At least one incident purchase of a psychotropic drug was identified for 11.1% of migrant women, 11.4% of Finnish-born women, 8.7% of migrant men and 9.8% of Finnish-born men. When controlled for age, sex, marital status, socioeconomic status and social assistance, migrants were less likely to purchase psychotropic drugs (adjusted hazard ratio 0.96, 95% confidence interval 0.93–0.98), but there was variation between different drug categories. Recent migrants and migrants from Asia and Sub-Saharan Africa were least likely to purchase drugs. Migrants from Nordic countries and other Western countries most closely resembled the Finnish-born controls. Conclusions Recent migrants in Finland appear to use fewer psychotropic drugs than native Finns. It is important to analyze the reasons for this pattern, as they may indicate delays in access to care or benefits. The heterogeneity of migrant populations must also be considered when developing services to better address their needs.

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HIV Drug Resistance Mutations in Non-B Subtypes After Prolonged Virological Failure on NNRTI-Based First-Line Regimens in Sub-Saharan Africa

JAIDS Journal of Acquired Immune Deficiency Syndromes ◽

10.1097/qai.0000000000001285 ◽

2017 ◽

Vol 75 (2) ◽

pp. e45-e54 ◽

Cited By ~ 17

Author(s):

Cissy Kityo ◽

Jennifer Thompson ◽

Immaculate Nankya ◽

Anne Hoppe ◽

Emmanuel Ndashimye ◽

...

Keyword(s):

Drug Resistance ◽

Virological Failure ◽

Sub Saharan Africa ◽

Resistance Mutations ◽

First Line ◽

Hiv Drug Resistance ◽

Drug Resistance Mutations ◽

Sub Saharan

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Analysis of strain distribution, migratory potential, and invasion history of fall armyworm populations in northern Sub-Saharan Africa

Scientific Reports ◽

10.1038/s41598-018-21954-1 ◽

2018 ◽

Vol 8 (1) ◽

Cited By ~ 38

Author(s):

Rodney N. Nagoshi ◽

Georg Goergen ◽

Kodjo Agbeko Tounou ◽

Komi Agboka ◽

Djima Koffi ◽

...

Keyword(s):

Strain Distribution ◽

Fall Armyworm ◽

Sub Saharan Africa ◽

Invasion History ◽

History Of ◽

Sub Saharan

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A high throughput multi-locus insecticide resistance marker panel for tracking resistance emergence and spread inAnopheles gambiae

10.1101/592279 ◽

2019 ◽

Cited By ~ 1

Author(s):

Eric R. Lucas ◽

Kirk A. Rockett ◽

Amy Lynd ◽

John Essandoh ◽

Nelson Grisales ◽

...

Keyword(s):

Insecticide Resistance ◽

High Throughput ◽

Democratic Republic Of Congo ◽

Novel Mutation ◽

Sub Saharan Africa ◽

Mutant Form ◽

Evolutionary Origins ◽

Wild Type Counterpart ◽

Control Programmes ◽

Sub Saharan

AbstractThe spread of resistance to insecticides in the mosquito vectors of diseases such as malaria and dengue poses a threat to the effectiveness of control programmes, which rely largely on insecticide-based interventions. Monitoring the resistance status of mosquito populations is therefore essential, but obtaining direct phenotypic measurements of resistance is laborious and error-prone. In contrast, high-throughput genotyping offers the prospect of quick and repeatable estimates of resistance, while also allowing the genotypic markers of resistance to be tracked and studied. We developed a panel of 28 known or putative markers of resistance in the major malaria vectorAnopheles gambiae, which we use to test the association of these markers with resistance and to study their geographic distribution. We screened resistance-phenotypedAn.gambiaefrom populations from a wide swathe of Sub-Saharan Africa (Burkina Faso, Ghana, Democratic Republic of Congo (DRC) and Kenya), and found evidence of resistance association for four mutations, including a novel mutation in the detoxification geneGste2(Gste2-119V). We also identified a gene duplication inGste2which combines a resistance-associated mutant form of the gene with its wild-type counterpart, potentially alleviating the costs of resistance. Finally, we describe the distribution of the multiple evolutionary origins ofkdrresistance, finding unprecedented levels of diversity in the DRC. This panel represents the first step towards developing a quantitative predictive genotypic model of insecticide resistance that can be used to screenAn.gambiaepopulations and predict resistance status.

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Managing a Transboundary Pest: The Fall Armyworm on Maize in Africa

10.5772/intechopen.96637 ◽

2021 ◽

Author(s):

Michael Hilary Otim ◽

Komi Kouma Mokpokpo Fiaboe ◽

Juliet Akello ◽

Barnabas Mudde ◽

Allan Tekkara Obonyom ◽

...

Keyword(s):

Host Range ◽

Sustainable Management ◽

Fall Armyworm ◽

Reproductive Rate ◽

Sub Saharan Africa ◽

Migration Ability ◽

Rapid Spread ◽

Sub Saharan ◽

Lepidoptera Noctuidae ◽

High Migration

The fall armyworm (Spodoptera frugiperda J.E Smith) (Lepidoptera: Noctuidae) invaded Africa in 2016, and has since spread to all countries in sub-Saharan Africa, causing devastating effects on mainly maize and sorghum. The rapid spread of this pest is aided by its high reproductive rate, high migration ability, wide host range and adaptability to different environments, among others. Since its introduction, many governments purchased and distributed pesticides for emergency control, with minimal regard to their efficacy. In this chapter, we review efforts towards managing this pest, highlight key challenges, and provide our thoughts on considerations for sustainable management of the pest.

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Immediate pools of malaria infections at diagnosis combined with targeted deep sequencing accurately quantifies frequency of drug resistance mutations

PeerJ ◽

10.7717/peerj.11794 ◽

2021 ◽

Vol 9 ◽

pp. e11794

Author(s):

Ozkan Aydemir ◽

Benedicta Mensah ◽

Patrick W. Marsh ◽

Benjamin Abuaku ◽

James Leslie Myers-Hansen ◽

...

Keyword(s):

Drug Resistance ◽

Diagnostic Testing ◽

Resistance Mutation ◽

Drug Resistance Mutation ◽

Sub Saharan Africa ◽

Resistance Mutations ◽

Drug Resistance Mutations ◽

Antimalarial Resistance ◽

Sample Pooling ◽

Sub Saharan

Antimalarial resistance surveillance in sub-Saharan Africa is often constrained by logistical and financial challenges limiting its breadth and frequency. At two sites in Ghana, we have piloted a streamlined sample pooling process created immediately by sequential addition of positive malaria cases at the time of diagnostic testing. This streamlined process involving a single tube minimized clinical and laboratory work and provided accurate frequencies of all known drug resistance mutations after high-throughput targeted sequencing using molecular inversion probes. Our study validates this method as a cost-efficient, accurate and highly-scalable approach for drug resistance mutation monitoring that can potentially be applied to other infectious diseases such as tuberculosis.

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Genomic Prediction of Tropical Maize Resistance to Fall Armyworm and Weevils: Genomic Selection Should Focus on Effective Training Set Determination

10.20944/preprints202007.0336.v1 ◽

2020 ◽

Author(s):

Arfang Badji ◽

Lewis Machida ◽

Daniel Bomet Kwemoi ◽

Frank Kumi ◽

Dennis Okii ◽

...

Keyword(s):

Genomic Selection ◽

Genomic Prediction ◽

Insect Pests ◽

Fall Armyworm ◽

Sub Saharan Africa ◽

Tropical Maize ◽

Training Set ◽

Maize Weevil ◽

Maize Resistance ◽

Sub Saharan

Genomic selection (GS) can accelerate variety release by shortening variety development phase when factors that influence prediction accuracies (PA) of genomic prediction (GP) models such as training set (TS) size and relationship with the breeding set (BS) are optimized beforehand. In this study, PAs for the resistance to fall armyworm (FAW) and maize weevil (MW) in a diverse tropical maize panel composed of 341 double haploid and inbred lines were estimated. Both phenotypic best linear unbiased predictors (BLUPs) and estimators (BLUEs) were predicted using 17 parametric, semi-parametric, and nonparametric algorithms with a 10-fold and 5 repetitions cross-validation strategy. n. For both MW and FAW resistance datasets with an RBTS of 37%, PAs achieved with BLUPs were at least as twice as higher than those realized with BLUEs. The PAs achieved with BLUPs for MW resistance traits: grain weight loss (GWL), adult progeny emergence (AP), and number of affected kernels (AK) varied from 0.66 to 0.82. The PAs were also high for FAW resistance RBTS datasets, varying from 0.694 to 0.714 (for RBTS of 37%) to 0.843 to 0.844 (for RBTS of 85%). The PAs for FAW resistance with PBTS were generally high varying from 0.83 to 0.86, except for one dataset that had PAs ranging from 0.11 to 0.75. GP models showed generally similar predictive abilities for each trait while the TS designation was determinant. There was a highly positive correlation (R=0.92***) between TS size and PAs for the RBTS approach while, for the PBTS, these parameters were highly negatively correlated (R=-0.44***), indicating the importance of the degree of kinship between the TS and the BS with the smallest TS (31%) achieving the highest PAs (0.86). This study paves the way towards the use of GS for maize resistance to insect pests in sub-Saharan Africa.

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