scholarly journals Monitoring of Target-Site Mutations Conferring Insecticide Resistance in Spodoptera frugiperda

Insects ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 545 ◽  
Author(s):  
Debora Boaventura ◽  
Macarena Martin ◽  
Alberto Pozzebon ◽  
David Mota-Sanchez ◽  
Ralf Nauen

Fall armyworm (FAW), Spodoptera frugiperda, a major pest of corn and native to the Americas, recently invaded (sub)tropical regions worldwide. The intensive use of insecticides and the high adoption of crops expressing Bacillus thuringiensis (Bt) proteins has led to many cases of resistance. Target-site mutations are among the main mechanisms of resistance and monitoring their frequency is of great value for insecticide resistance management. Pyrosequencing and PCR-based allelic discrimination assays were developed and used to genotype target-site resistance alleles in 34 FAW populations from different continents. The diagnostic methods revealed a high frequency of mutations in acetylcholinesterase, conferring resistance to organophosphates and carbamates. In voltage-gated sodium channels targeted by pyrethroids, only one population from Indonesia showed a mutation. No mutations were detected in the ryanodine receptor, suggesting susceptibility to diamides. Indels in the ATP-binding cassette transporter C2 associated with Bt-resistance were observed in samples collected in Puerto Rico and Brazil. Additionally, we analyzed all samples for the presence of markers associated with two sympatric FAW host plant strains. The molecular methods established show robust results in FAW samples collected across a broad geographical range and can be used to support decisions for sustainable FAW control and applied resistance management.

Insects ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 758
Author(s):  
Mahesh Kulye ◽  
Sonja Mehlhorn ◽  
Debora Boaventura ◽  
Nigel Godley ◽  
Sreedevi Kodikoppalu Venkatesh ◽  
...  

Fall armyworm (FAW), Spodoptera frugiperda, is a major pest of maize in the Americas and recently invaded the Eastern hemisphere. It was first detected in India in 2018 and is considered a major threat to maize production. FAW control largely relies on the application of chemical insecticides and transgenic crops expressing Bacillus thuringiensis insecticidal proteins. Assessing FAW resistance and insecticide susceptibility is a cornerstone to develop sustainable resistance management strategies. In this study, we conducted more than 400 bioassays to assess the efficacy of nine insecticides from seven mode-of-action classes against 47 FAW populations collected in 2019 and 2020 across various geographical areas in India. The resistance status of the field-collected populations was compared to an Indian population sampled in 2018, and an insecticide susceptible reference population collected in 2005 in Brazil. Low to moderate resistance levels were observed for thiodicarb, chlorpyriphos, deltamethrin, chlorantraniliprole and flubendiamide in several populations (including the reference population collected in 2018). The highest resistance ratios were observed for deltamethrin which likely compromises recommended label rates for pyrethroid insecticides in general. Our data provide a useful baseline for future FAW resistance monitoring initiatives and highlight the need to implement insecticide resistance management strategies.


2021 ◽  
Vol 20 (3) ◽  
pp. 783-791 ◽  
Author(s):  
Dan-dan ZHANG ◽  
Yu-tao XIAO ◽  
Peng-jun XU ◽  
Xian-ming YANG ◽  
Qiu-lin WU ◽  
...  

2021 ◽  
Author(s):  
Rubens Hideo Kanno ◽  
Aline Guidolin ◽  
Fernando Padovez ◽  
Juliana Rodrigues ◽  
Celso Omoto

Insecticide resistance is usually associated with fitness costs. The magnitude of fitness costs is affected by environmental and ecological factors. Here, we explored how host plants could affect fitness costs associated with insecticide resistance. Initially, spinetoram-resistant (RR) and susceptible (SS) strains of Spodoptera frugiperda were selected using F2 screen from a population collected in Sao Desiderio, Bahia State, Brazil in 2018. Besides de RR and SS strains, fitness costs were also assessed for a heterozygous strain (RS). Life-history traits were evaluated to estimate population growth parameters of neonate larvae of each strain fed on corn, soybean and cotton plants. Compared to the SS strain, the relative fitness of the RR strain, based on intrinsic rate of population increase, was 1.06, 0.84 and 0.67 on plants of corn, soybean and cotton respectively. The relative fitness of the RS strain was similar to the SS strain regardless the host plant, suggesting a recessive fitness cost. No differences were found between the strains fed on corn plants. The larval development time was greater for RR strain fed on soybean and cotton plants compared to RS and SS strain. Low survival rate and fecundity of the RR strain were found when larvae fed on plants of soybean and cotton. The results of this study demonstrated that fitness costs of spinetoram resistance in S. frugiperda depend strongly on the host plants that S. frugiperda larvae fed on. Such information can be used to design resistance management strategies considering the host plants of the agricultural landscape. Keywords: fall armyworm; spinosyns; insect resistance management; relative fitness.


2020 ◽  
Vol 4 (3) ◽  
pp. 149-153
Author(s):  
Ahmad Hassan Tahir ◽  
Muhammad Tariq ◽  
Aqsa Mazhar ◽  
Muhammad Shehzad

Spodoptera frugiperda (Lepidoptera: Noctuidae) commonly known as fall armyworm (FAW), is a pest that invaded the sub-tropical and tropical regions of America. In 2016, it was reported for the first time in central Africa and within a year it was reported from many countries of Africa. It then spread in Asia and in 2018 it was reported in India, and now its infestation was seen in Pakistan. Its strong flight, climatic adaptableness and large host range makes it a good colonizing agent as compared to other species of Spodoptera. In potential managing strategies we must know about its primary information such as its biology, host range, habitat and favorable conditions. Identification and life cycle is the most important process in the management of this pest. IPM strategies include physical and cultural control, botanical control, biological control and chemical control. These strategies will help in management of FAW. All these aspects have been reviewed in this article.


2019 ◽  
Vol 76 (1) ◽  
pp. 47-54 ◽  
Author(s):  
Debora Boaventura ◽  
Anderson Bolzan ◽  
Fernando EO Padovez ◽  
Daniela M Okuma ◽  
Celso Omoto ◽  
...  

2020 ◽  
Vol 58 (5) ◽  
pp. 543-550
Author(s):  
Seo Hye Park ◽  
Hojong Jun ◽  
Seong Kyu Ahn ◽  
Jinyoung Lee ◽  
Sung-Lim Yu ◽  
...  

Mosquitoes are globally distributed and important vectors for the transmission of many human diseases. Mosquito control is a difficult task and the cost of preventing mosquito-borne diseases is much lower than that for curing the associated diseases. Thus, chemical control remains the most effective tool for mosquito. Due to the long-term intensive use of insecticides to control mosquito vectors, resistance to most chemical insecticides has been reported. This study aimed to investigate the relationship between insecticide resistance and target site mutation of L1014 kdr and G119 ace alleles in 5 species/species group of mosquitoes (Aedes vexans, Ae. albopictus, Anopheles spp., Culex pipiens complex, and Cx. tritaeniorhynchus) obtained from 6 collection sites. For Anopheles spp., the proportion of mosquitoes with mutated alleles in L1014 was 88.4%, homozygous resistant genotypes were observed in 46.7%, and heterozygous resistant genotypes were observed in 41.8%. For the Cx. pipiens complex and Cx. tritaeniorhynchus species, homozygous resistant genotypes were found in 25.9% and 9.8%, respectively. However, target site mutation of L1014 in the Ae. vexans nipponii and Ae. albopictus species was not observed. Anopheles spp., Cx. pipiens complex, and Cx. tritaeniorhynchus mosquitoes were resistant to deltamethrin and chlorpyriphos, whereas Ae. vexans nipponii and Ae. albopictus were clearly susceptible. We also found a correlation between the resistance phenotype and the presence of the L1014 kdr and G119 ace mutations only in the Anopheles spp. population. In this study, we suggest that insecticide resistance poses a growing threat and resistance management must be integrated into all mosquito control 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.


Sign in / Sign up

Export Citation Format

Share Document