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Braga LE, Warpechowski LF, Diniz LH, Dallanora A, Reis AC, Farias JR, Bernardi O. Characterizing the differential susceptibility and resistance to insecticides in populations of Chrysodeixis includens and Rachiplusia nu (Lepidoptera: Noctuidae) in Brazil. PEST MANAGEMENT SCIENCE 2024. [PMID: 38801197 DOI: 10.1002/ps.8197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 05/07/2024] [Accepted: 05/13/2024] [Indexed: 05/29/2024]
Abstract
BACKGROUND Chrysodeixis includens (Walker) and Rachiplusia nu (Guenée) are major Plusiinae pests of soybean in the Southern Cone region of South America. In recent decades, C. includens was the main defoliator of soybean in Brazil, but from 2021 onwards, R. nu emerged as an important soybean pest in various regions of the country. Here, we characterize the differential susceptibility and resistance to insecticides in these Plusiinae pests from two soybean regions of Brazil. RESULTS Except for spinetoram and chlorfenapyr (comparable lethality against both species) and a Bt-based biopesticide (more lethal for C. includens), the tested insecticides showed higher lethality against R. nu than against C. includens, but populations of the same species, even separated by long distances, presented similar resistance levels. For both species, the 90% lethal concentration (LC90) values of most insecticides were higher than the field-recommended dose. Nevertheless, the field-recommended doses of spinetoram, metaflumizone, emamectin benzoate, cyclaniliprole and chlorfenapyr showed comparable control efficacy against both species, whereas indoxacarb, chlorantraniliprole, flubendiamide, teflubenzuron and chlorfluazuron were more lethal for R. nu, and methoxyfenozide and the Bt-based insecticide were more lethal for C. includens. Thiodicarb, methomyl and lambda-cyhalothrin showed low lethality against both species. CONCLUSIONS Large interspecific differences in the susceptibility to insecticides was found in major Plusiinae pests of soybean in Brazil. Furthermore, variations in susceptibility to insecticides occurred consistently among species and populations, regardless of the collection site and thus despite unequal temporal and spatial exposure to insecticides. These results demonstrate that accurate species identification is essential for effective control of Plusiinae in soybean. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Luiz E Braga
- Department of Plant Protection, Federal University of Santa Maria, Santa Maria, Brazil
| | - Luiz F Warpechowski
- Department of Plant Protection, Federal University of Santa Maria, Santa Maria, Brazil
| | - Luis Hm Diniz
- Department of Plant Protection, Federal University of Santa Maria, Santa Maria, Brazil
| | - Arthur Dallanora
- Department of Plant Protection, Federal University of Santa Maria, Santa Maria, Brazil
| | - Alexandre C Reis
- Department of Plant Protection, Federal University of Santa Maria, Santa Maria, Brazil
| | | | - Oderlei Bernardi
- Department of Plant Protection, Federal University of Santa Maria, Santa Maria, Brazil
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Lee S, Ahn SJ. CRISPR/Cas9-mediated knockout of scarlet gene produces eye color mutants in the soybean looper, Chrysodeixis includens. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2024; 115:e22100. [PMID: 38500478 DOI: 10.1002/arch.22100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 02/29/2024] [Accepted: 03/06/2024] [Indexed: 03/20/2024]
Abstract
The CRISPR/Cas9 technology has greatly progressed research on non-model organisms, demonstrating successful applications in genome editing for various insects. However, its utilization in the case of the soybean looper, Chrysodeixis includens, a notable pest affecting soybean crops, has not been explored due to constraints such as limited genomic information and the embryonic microinjection technique. This study presents successful outcomes in generating heritable knockout mutants for a pigment transporter gene, scarlet, in C. includens through CRISPR/Cas9-mediated mutagenesis. The scarlet locus identified in the genome assembly of C. includens consists of 14 exons, with a coding sequence extending for 1,986 bp. Two single guide RNAs (sgRNAs) were designed to target the first exon of scarlet. Microinjection of these two sgRNAs along with the Cas9 protein into fresh embryos resulted in the successful production of variable phenotypes, particularly mutant eyes. The observed mutation rate accounted for about 16%. Genotype analysis revealed diverse indel mutations at the target site, presumably originating from double-strand breaks followed by the nonhomologous end joining repair, leading to a premature stop codon due to frame shift. Single-pair mating of the mutant moths produced G1 offspring, and the establishment of a homozygous mutant strain occurred in G2. The mutant moths exhibited lightly greenish or yellowish compound eyes in both sexes, confirming the involvement of scarlet in pigmentation in C. includens. Notably, the CRISPR/Cas9-mediated genome editing technique serves as a visible phenotypic marker, demonstrating its proof-of-concept applicability in C. includens, as other pigment transporter genes have been utilized as visible markers to establish genetic control for various insects. These results provide the first successful case that the CRISPR/Cas9 method effectively induces mutations in C. includes, an economically important soybean insect pest.
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Affiliation(s)
- Sujin Lee
- Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, Mississippi State, Mississippi, USA
| | - Seung-Joon Ahn
- Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, Mississippi State, Mississippi, USA
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Posos-Parra O, Mota-Sanchez D, Pittendrigh BR, Wise JC, DiFonzo CD, Patterson E. Characterization of the inheritance of field-evolved resistance to diamides in the fall armyworm (Spodoptera frugiperda) (Lepidoptera: Noctuidae) population from Puerto Rico. PLoS One 2024; 19:e0295928. [PMID: 38394153 PMCID: PMC10889863 DOI: 10.1371/journal.pone.0295928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 11/29/2023] [Indexed: 02/25/2024] Open
Abstract
The fall armyworm (Spodoptera frugiperda) is one of the most destructive pests of corn. New infestations have been reported in the East Hemisphere, reaching India, China, Malaysia, and Australia, causing severe destruction to corn and other crops. In Puerto Rico, practical resistance to different mode of action compounds has been reported in cornfields. In this study, we characterized the inheritance of resistance to chlorantraniliprole and flubendiamide and identified the possible cross-resistance to cyantraniliprole and cyclaniliprole. The Puerto Rican (PR) strain showed high levels of resistance to flubendiamide (RR50 = 2,762-fold) and chlorantraniliprole (RR50 = 96-fold). The inheritance of resistance showed an autosomal inheritance for chlorantraniliprole and an X-linked inheritance for flubendiamide. The trend of the dominance of resistance demonstrated an incompletely recessive trait for H1 (♂ SUS × ♀ PR) × and an incompletely dominant trait for H2 (♀ SUS × ♂ PR) × for flubendiamide and chlorantraniliprole. The PR strain showed no significant presence of detoxification enzymes (using synergists: PBO, DEF, DEM, and VER) to chlorantraniliprole; however, for flubendiamide the SR = 2.7 (DEM), SR = 3.2 (DEF) and SR = 7.6 (VER) indicated the role of esterases, glutathione S- transferases and ABC transporters in the metabolism of flubendiamide. The PR strain showed high and low cross-resistance to cyantraniliprole (74-fold) and cyclaniliprole (11-fold), respectively. Incomplete recessiveness might lead to the survival of heterozygous individuals when the decay of diamide residue occurs in plant tissues. These results highlight the importance of adopting diverse pest management strategies, including insecticide rotating to manage FAW populations in Puerto Rico and other continents.
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Affiliation(s)
- Omar Posos-Parra
- Department of Entomology, Michigan State University, East Lansing, Michigan, United States of America
| | - David Mota-Sanchez
- Department of Entomology, Michigan State University, East Lansing, Michigan, United States of America
| | - Barry R. Pittendrigh
- Department of Entomology, Purdue University, West Lafayette, Indiana, United States of America
| | - John C. Wise
- Department of Entomology, Michigan State University, East Lansing, Michigan, United States of America
| | - Christina D. DiFonzo
- Department of Entomology, Michigan State University, East Lansing, Michigan, United States of America
| | - Eric Patterson
- Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, Michigan, United States of America
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Isbilir S, Catchot B, Catchot L, Musser FR, Ahn SJ. Molecular characterization and expression patterns of a ryanodine receptor in soybean looper, Chrysodeixis includens. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2023; 114:e22047. [PMID: 37602813 DOI: 10.1002/arch.22047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Revised: 07/28/2023] [Accepted: 08/02/2023] [Indexed: 08/22/2023]
Abstract
Diamide insecticides, such as chlorantraniliprole, have been widely used to control insect pests by targeting the insect ryanodine receptor (RyR). Due to the efficacious insecticidal activity of diamides, as well as an increasing number of resistance cases, the molecular structure of RyR has been studied in many economically important insects. However, no research has been conducted on diamide resistance and RyR in the soybean looper, Chrysodeixis includens, a significant crop pest. In this study, we found moderate resistance to chlorantraniliprole in a field population from Puerto Rico and sequenced the full-length cDNA of the C. includens RyR gene, which encodes a 5124 amino acid-long protein. Genomic analysis revealed that the CincRyR gene consists of 113 exons, one of the largest exon numbers reported for RyR. Alternative splicing sites were detected in the cytosolic region. The protein sequence showed high similarity to other noctuid RyRs. Conserved structural features included the selectivity filter motif critical for ryanodine binding and ion conduction, as well as various domains involved in ion transport. Two mutation sites associated with diamide resistance in other insects were screened but not found in the Puerto Rico field populations or in the susceptible lab strain. Gene expression analysis indicated high expression of RyR in the third instar larval stage, particularly in muscle-containing tissues. Furthermore, exposure to a sublethal dose of chlorantraniliprole reduced RyR expression levels after 96 h. This study provides a molecular basis for understanding RyR structure and sheds light on potential mechanisms of diamide resistance in C. includens.
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Affiliation(s)
- Sena Isbilir
- Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, Starkville, Mississippi, USA
| | - Beverly Catchot
- Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, Starkville, Mississippi, USA
| | - Lauren Catchot
- Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, Starkville, Mississippi, USA
| | - Fred R Musser
- Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, Starkville, Mississippi, USA
| | - Seung-Joon Ahn
- Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, Starkville, Mississippi, USA
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Santos NC, Silva JED, Santos ACC, Dantas JDO, Tavares SRSA, Andrade VS, Oliveira SDDS, Blank AF, Araújo APA, Bacci L. Bioactivity of essential oils from Croton grewioides and its major compounds: toxicity to soybean looper Chrysodeixis includens and selectivity to the predatory stink bug Podisus nigrispinus. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:18798-18809. [PMID: 36217049 DOI: 10.1007/s11356-022-23414-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 09/28/2022] [Indexed: 06/16/2023]
Abstract
Natural biological control is a key factor that ensures the regulation of insect pest populations in agroecosystems. However, the indiscriminate use of pesticides has compromised this environmental service. Thus, the search for environmentally safe pesticides is an increasing requirement for sustainable food production. In this study, we analyzed the toxicity of essential oils from two accessions (CGR112 and CGR126) of Croton grewioides and its major compounds, methyl eugenol and eugenol, on the soybean pest Chrysodeixis includens. In addition, we investigated the sublethal effects of these compounds on the predatory bug Podisus nigrispinus, analyzing its developmental, reproduction and life table parameters. Essential oils and their major compounds were toxic to C. includens and P. nigrispinus. In general, the presence of eugenol made the essential oil more toxic to the pest and selective to the natural enemy. Eugenol was the most toxic compound for 2nd instar larvae of C. includens at LD50, followed by CGR126 essential oil from C. grewioides which was equally toxic at higher doses. The estimated lethal times for essential oils to cause mortality in 50% of the population of C. includens were less than 15 h. There was selectivity of the essential oil of CGR126 accession of C. grewioides at lethal doses above 90%. Although the treatments showed little effect on the development of P. nigrispinus, body mass and reproductive parameters were negatively affected, with the exception of the essential oil of CGR126 accession of C. grewioides. The essential oil of C. grewioides may be a promising active ingredient for the synthesis of new insecticides, which are efficient against C. includens and at the same time are safer for the natural enemy P. nigrispinus.
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Affiliation(s)
- Natielli Conceição Santos
- Departamento de Engenharia Agronômica, Universidade Federal de Sergipe, Av. Marechal Rondon s/n, São Cristóvão, SE, 49100-000, Brazil
| | - Jefferson Elias da Silva
- Departamento de Engenharia Agronômica, Universidade Federal de Sergipe, Av. Marechal Rondon s/n, São Cristóvão, SE, 49100-000, Brazil
| | - Ane Caroline Celestino Santos
- Departamento de Engenharia Agronômica, Universidade Federal de Sergipe, Av. Marechal Rondon s/n, São Cristóvão, SE, 49100-000, Brazil
| | - Jaciele de Oliveira Dantas
- Departamento de Engenharia Agronômica, Universidade Federal de Sergipe, Av. Marechal Rondon s/n, São Cristóvão, SE, 49100-000, Brazil
| | | | - Valfran Silva Andrade
- Departamento de Engenharia Agronômica, Universidade Federal de Sergipe, Av. Marechal Rondon s/n, São Cristóvão, SE, 49100-000, Brazil
| | - Sara Dayan da Silva Oliveira
- Departamento de Engenharia Agronômica, Universidade Federal de Sergipe, Av. Marechal Rondon s/n, São Cristóvão, SE, 49100-000, Brazil
| | - Arie Fitzgerald Blank
- Departamento de Engenharia Agronômica, Universidade Federal de Sergipe, Av. Marechal Rondon s/n, São Cristóvão, SE, 49100-000, Brazil
| | | | - Leandro Bacci
- Departamento de Engenharia Agronômica, Universidade Federal de Sergipe, Av. Marechal Rondon s/n, São Cristóvão, SE, 49100-000, Brazil.
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Amaral FSDAE, Kanno RH, do Nascimento ARB, Guidolin AS, Omoto C. Trends towards Lower Susceptibility of Spodoptera frugiperda (Lepidoptera: Noctuidae) to Teflubenzuron in Brazil: An Evidence for Field-Evolved Resistance. INSECTS 2023; 14:129. [PMID: 36835698 PMCID: PMC9965761 DOI: 10.3390/insects14020129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 01/20/2023] [Accepted: 01/23/2023] [Indexed: 06/18/2023]
Abstract
Susceptibility monitoring to insecticides is a key component to implementing insecticide resistance management (IRM) programs. In this research, the susceptibility to teflubenzuron in Spodoptera frugiperda (J.E Smith) was monitored in more than 200 field-collected populations from major corn-growing regions of Brazil, from 2004 to 2020. Initially, we defined a diagnostic concentration of 10 µg mL-1 of teflubenzuron using a diet-overlay bioassay for monitoring the susceptibility. A variation in the susceptibility to teflubenzuron in S. frugiperda was detected among populations from different locations. We also detected a significant reduction in the susceptibility to teflubenzuron throughout time in all the populations of S. frugiperda evaluated, with larval survival at diagnostic concentration varying from values of <5% in 2004 to up 80% in 2020. Thus, this research provides evidence of field-evolved resistance of S. frugiperda to teflubenzuron and reinforces that IRM practices are urgently needed to be implemented in Brazil.
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Horikoshi RJ, Dourado PM, Berger GU, de S Fernandes D, Omoto C, Willse A, Martinelli S, Head GP, Corrêa AS. Large-scale assessment of lepidopteran soybean pests and efficacy of Cry1Ac soybean in Brazil. Sci Rep 2021; 11:15956. [PMID: 34354186 PMCID: PMC8342623 DOI: 10.1038/s41598-021-95483-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 07/26/2021] [Indexed: 02/06/2023] Open
Abstract
The soybean technology MON 87701 × MON 89788, expressing Cry1Ac and conferring tolerance to glyphosate, has been widely adopted in Brazil since 2013. However, pest shifts or resistance evolution could reduce the benefits of this technology. To assess Cry1Ac soybean performance and understand the composition of lepidopteran pest species attacking soybeans, we implemented large-scale sampling of larvae on commercial soybean fields during the 2019 and 2020 crop seasons to compare with data collected prior to the introduction of Cry1Ac soybeans. Chrysodeixis includens was the main lepidopteran pest in non-Bt fields. More than 98% of larvae found in Cry1Ac soybean were Spodoptera spp., although the numbers of Spodoptera were similar between Cry1Ac soybean and non-Bt fields. Cry1Ac soybean provided a high level of protection against Anticarsia gemmatalis, C. includens, Chloridea virescens and Helicoverpa spp. Significant reductions in insecticide sprays for lepidopteran control in soybean were observed from 2012 to 2019. Our study showed that C. includens and A. gemmatalis continue to be primary lepidopteran pests of soybean in Brazil and that Cry1Ac soybean continues to effectively manage the target lepidopteran pests. However, there was an increase in the relative abundance of non-target Spodoptera spp. larvae in both non-Bt and Cry1Ac soybeans.
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Affiliation(s)
- Renato J Horikoshi
- Bayer Crop Science, São Paulo, SP, Brazil.
- Departamento de Entomologia e Acarologia, Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Piracicaba, SP, Brazil.
| | | | | | - Davi de S Fernandes
- Departamento de Entomologia e Acarologia, Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Piracicaba, SP, Brazil
| | - Celso Omoto
- Departamento de Entomologia e Acarologia, Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Piracicaba, SP, Brazil
| | - Alan Willse
- Regulatory Science, Bayer Crop Science, Chesterfield, MO, 63017, USA
| | - Samuel Martinelli
- Regulatory Science, Bayer Crop Science, Chesterfield, MO, 63017, USA
| | - Graham P Head
- Regulatory Science, Bayer Crop Science, Chesterfield, MO, 63017, USA
| | - Alberto S Corrêa
- Departamento de Entomologia e Acarologia, Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Piracicaba, SP, Brazil
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Evaluation of Reference Genes and Expression Level of Genes Potentially Involved in the Mode of Action of Cry1Ac and Cry1F in a Susceptible Reference Strain of Chrysodeixis includens. INSECTS 2021; 12:insects12070598. [PMID: 34209276 PMCID: PMC8304518 DOI: 10.3390/insects12070598] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 06/22/2021] [Accepted: 06/29/2021] [Indexed: 11/17/2022]
Abstract
Simple Summary Soybean looper (a moth species) is a major pest of soybean plants in the American continent and its larvae need to be kept under economic damage thresholds to guarantee sustainable yields. Soybean looper control relies mostly on the use of insecticides and genetically modified crops expressing Bacillus thuringiensis (Bt) insecticidal proteins. Due to the high selection pressure exerted by these control measures, resistance has developed to different insecticides and Bt proteins. Here, we tested the basal sensitivity of a soybean looper laboratory reference strain against two insecticidal proteins and determined the level of expression of potential receptors of these proteins across all (six) larval stages. Furthermore, we identified stable reference genes across all larval stages to normalize gene expression data obtained by quantitative polymerase chain reaction (qPCR). The results presented in this communication are useful to support future studies on insecticide and insecticidal protein resistance in soybean looper. Abstract Soybean looper (SBL), Chrysodeixis includens (Walker), is one of the major lepidopteran pests of soybean in the American continent. SBL control relies mostly on the use of insecticides and genetically modified crops expressing Bacillus thuringiensis (Bt) insecticidal Cry proteins. Due to the high selection pressure exerted by these control measures, resistance has developed to different insecticides and Bt proteins. Nevertheless, studies on the mechanistic background are still scarce. Here, the susceptibility of the laboratory SBL-Benzon strain to the Bt proteins Cry1Ac and Cry1F was determined in diet overlay assays and revealed a greater activity of Cry1Ac than Cry1F, thus confirming results obtained for other sensitive SBL strains. A reference gene study across larval stages with four candidate genes revealed that RPL10 and EF1 were the most stable genes for normalization of gene expression data obtained by RT-qPCR. Finally, the basal expression levels of eight potential Bt protein receptor genes in six larval instars were analyzed, including ATP-binding cassette (ABC) transporters, alkaline phosphatase, aminopeptidases, and cadherin. The results presented here provide fundamental knowledge to support future SBL resistance studies.
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Ekoka E, Maharaj S, Nardini L, Dahan-Moss Y, Koekemoer LL. 20-Hydroxyecdysone (20E) signaling as a promising target for the chemical control of malaria vectors. Parasit Vectors 2021; 14:86. [PMID: 33514413 PMCID: PMC7844807 DOI: 10.1186/s13071-020-04558-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 12/19/2020] [Indexed: 01/07/2023] Open
Abstract
With the rapid development and spread of resistance to insecticides among anopheline malaria vectors, the efficacy of current World Health Organization (WHO)-approved insecticides targeting these vectors is under threat. This has led to the development of novel interventions, including improved and enhanced insecticide formulations with new targets or synergists or with added sterilants and/or antimalarials, among others. To date, several studies in mosquitoes have revealed that the 20-hydroxyecdysone (20E) signaling pathway regulates both vector abundance and competence, two parameters that influence malaria transmission. Therefore, insecticides which target 20E signaling (e.g. methoxyfenozide and halofenozide) may be an asset for malaria vector control. While such insecticides are already commercially available for lepidopteran and coleopteran pests, they still need to be approved by the WHO for malaria vector control programs. Until recently, chemicals targeting 20E signaling were considered to be insect growth regulators, and their effect was mostly studied against immature mosquito stages. However, in the last few years, promising results have been obtained by applying methoxyfenozide or halofenozide (two compounds that boost 20E signaling) to Anopheles populations at different phases of their life-cycle. In addition, preliminary studies suggest that methoxyfenozide resistance is unstable, causing the insects substantial fitness costs, thereby potentially circumventing one of the biggest challenges faced by current vector control efforts. In this review, we first describe the 20E signaling pathway in mosquitoes and then summarize the mechanisms whereby 20E signaling regulates the physiological processes associated with vector competence and vector abundance. Finally, we discuss the potential of using chemicals targeting 20E signaling to control malaria vectors.![]()
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Affiliation(s)
- Elodie Ekoka
- WITS Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa. .,Centre for Emerging, Zoonotic & Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg, South Africa.
| | - Surina Maharaj
- WITS Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.,Centre for Emerging, Zoonotic & Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg, South Africa
| | - Luisa Nardini
- WITS Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.,Centre for Emerging, Zoonotic & Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg, South Africa
| | - Yael Dahan-Moss
- WITS Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.,Centre for Emerging, Zoonotic & Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg, South Africa
| | - Lizette L Koekemoer
- WITS Research Institute for Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.,Centre for Emerging, Zoonotic & Parasitic Diseases, National Institute for Communicable Diseases, Johannesburg, South Africa
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