Molecular innovations underlying resistance to nicotine and neonicotinoids in the aphid Myzus persicae

Tetraniliprole risk assessment: Unveiling a hidden threat for managing a generalist herbivore

Insecticide resistance poses a significant challenge in managing generalist herbivores such as the tobacco cutworm (TCW), Spodoptera litura. This study investigates the potential risks associated with using the novel diamide insecticide tetraniliprole to control TCW. A tetraniliprole-resistant strain was developed through twelve generations of laboratory selection, indicating an intermediate risk of resistance development. Field monitoring in China revealed a significant incidence of resistance, particularly in the Nanchang (NC) population (>100-fold). Tetraniliprole showed moderate to high cross-resistance to multiple insecticides and was autosomally inherited with incomplete dominance, controlled by multiple genes, some of which belong to the cytochrome P450 family associated with enhanced detoxification. Life table studies indicated transgenerational hormesis, stimulating TCW female fecundity and increasing population net reproduction rates (R0). These findings suggest a potential for pest resurgence under tetraniliprole use. The integrated risk assessment provides a basis for the sustainable management of TCW using tetraniliprole.

Electrochemical sensing mechanisms of neonicotinoid pesticides and recent progress in utilizing functional materials for electrochemical detection platforms

The excessive residue of neonicotinoid pesticides in the environment and food poses a severe threat to human health, necessitating the urgent development of a sensitive and efficient method for detecting trace amounts of these pesticides. Electrochemical sensors, characterized by their simplicity of operation, rapid response, low cost, strong selectivity, and high feasibility, have garnered significant attention for their immense potential in swiftly detecting trace target molecules. The detection capability of electrochemical sensors primarily relies on the catalytic activity of electrode materials towards the target analyte, efficient loading of biomolecular functionalities, and the effective conversion of interactions between the target analyte and its receptor into electrical signals. Electrode materials with superior performance play a crucial role in enhancing the detection capability of electrochemical sensors. With the continuous advancement of nanotechnology, particularly the widespread application of novel functional materials, there is paramount significance in broadening the applicability and expanding the detection range of pesticide sensors. This comprehensive review encapsulates the electrochemical detection mechanisms of neonicotinoid pesticides, providing detailed insights into the outstanding roles, advantages, and limitations of functional materials such as carbon-based materials, metal-organic framework materials, supramolecular materials, metal-based nanomaterials, as well as molecular imprinted materials, antibodies/antigens, and aptamers as molecular recognition elements in the construction of electrochemical sensors for neonicotinoid pesticides. Furthermore, prospects and challenges facing various electrochemical sensors based on functional materials for neonicotinoid pesticides are discussed, providing valuable insights for the future development and application of biosensors for simplified on-site detection of agricultural residues.

Fusion dsRNA designs incorporating multiple target sequences can enhance the aphid control capacity of an RNAi-based strategy

BACKGROUND

RNA interference (RNAi) is the sequence-dependent suppression of gene expression by double-stranded RNA (dsRNA). This is a promising strategy for the control of insect pests because dsRNA can be rationally designed to maximize efficacy and biosafety, the latter by using sequences that are found in target pests but are safe for non-target insects. However, this has yet to be optimized in aphids, destructive sap-sucking pests that also transmit plant viruses. We used the green peach aphid (Myzus persicae) as a case study to optimize the efficiency of RNAi by applying a novel fusion dsRNA design.

RESULTS

Comparative transcriptomics revealed a number of genes that are induced in feeding aphids, and eight candidate genes were chosen as RNAi targets. To improve RNAi efficiency, our fusion dsRNA design approach combined optimal gene fragments (highly conserved in several aphid species but with less homology in beneficial insects such as the predator ladybeetle Propylea japonica) from three candidate genes. We compared this RNAi-based biological control approach with conventional chemical control using imidacloprid. We found that the fusion dsRNA strategy inhibited the aphid population to a significantly greater extent than single-target RNAi and did not affect ladybeetle fitness, allowing an additive effect between RNAi and natural predation, whereas imidacloprid was harmful to aphids and ladybeetles.

CONCLUSION

Our fusion dsRNA design approach enhances the ability of RNAi to control aphids without harming natural predators. © 2024 Society of Chemical Industry.

Genome assembly and transcriptomic analysis to elucidate the ability of Nasonovia ribisnigri to break host plant resistance

Aphid genomic resources enable the study of complex life history traits and provide information on vector biology, host adaption and speciation. The currant-lettuce aphid (Nasonovia ribisnigri (Hemiptera: Aphididae) (Mosley)) is a cosmopolitan pest of outdoor lettuce (Lactuca sativa (Asterales: Asteraceae) (Linnaeus)). Until recently, the use of resistant cultivars was an effective method for managing N. ribisnigri. A resistant cultivar containing a single gene (Nr-locus), introduced in the 1980s, conferred complete resistance to feeding. Overreliance of this Nr-locus in lettuce resulted in N. ribisnigri's ability to break resistance mechanism, with first reports during 2003. Our work attempts to understand which candidate gene(s) are associated with this resistance-breaking mechanism. We present two de novo draft assembles for N. ribisnigri genomes, corresponding to both avirulent (Nr-locus susceptible) and virulent (Nr-locus resistant) biotypes. Changes in gene expression of the two N. ribisnigri biotypes were investigated using transcriptomic analyses of RNA-sequencing (RNA-seq) data to understand the potential mechanisms of resistance to the Nr-locus in lettuce. The draft genome assemblies were 94.2% and 91.4% complete for the avirulent and virulent biotypes, respectively. Out of the 18,872 differentially expressed genes, a single gene/locus was identified in N. ribisnigri that was shared between two resistant-breaking biotypes. This locus was further explored and validated in Real-Time Quantitative Reverse Transcription PCR (qRT-PCR) experiments and has predicted localisations in both the cytoplasm and nucleus. This is the first study to provide evidence that a single gene/locus is likely responsible for the ability of N. ribisnigri to overcome the Nr-locus resistance in the lettuce host.

Rifampicin synergizes the toxicity of insecticides against the green peach aphid, Myzus persicae

Myzus persicae is an important pest that has developed resistance to nearly all currently used insecticidal products. The employment of insecticide synergists is one of the effective strategies that need to be developed for the management of this resistance. Our study showed that treatment with a combination of the antibiotic, rifampicin, with imidacloprid, cyantraniliprole, or clothianidin significantly increased their toxicities against M. persicae, by 2.72, 3.59, and 2.41 folds, respectively. Rifampicin treatment led to a noteworthy reduction in the activities of multifunctional oxidases (by 32.64%) and esterases (by 23.80%), along with a decrease in the expression of the CYP6CY3 gene (by 58.57%) in M. persicae. It also negatively impacted the fitness of the aphids, including weight, life span, number of offspring, and elongation of developmental duration. In addition, bioassays showed that the combination of rifampicin and a detoxification enzyme inhibitor, piperonyl butoxide, or dsRNA of CYP6CY3 further significantly improved the toxicity of imidacloprid against M. persicae, by 6.19- and 7.55-fold, respectively. The present study suggests that development of active ingredients such as rifampicin as candidate synergists, show promise to overcome metabolic resistance to insecticides in aphids.

Pyrethroid and carbamate resistance in Czech populations of Myzus persicae (Sulzer) from oilseed rape

BACKGROUND

Failures in controlling Myzus persicae by pyrethroids and carbamates have been observed in Czechia since 2018. Eleven populations collected from Czech oilseed rape fields during 2018-2021 were tested for susceptibility to 11 insecticides. The presence of a single nucleotide polymorphism (SNP) leading to knockdown resistance in M. persicae populations was screened using allelic discriminating quantitative real-time polymerase chain reaction (qPCR). The presence of mutations related with the resistance of M. persicae to pyrethroids and carbamates was detected by sequencing paratype voltage-gated sodium channel and acetylcholinesterase 2 genes, respectively.

RESULTS

Resistance to alpha-cypermethrin and pirimicarb was detected in most of the tested populations. The L1014F mutation was detected in 44.5% of M. persicae individuals surviving the field-recommended dose of alpha-cypermethrin. Sequencing of partial para gene for paratype voltage-gated sodium channel detected five different SNPs leading to four amino acid substitutions (kdr L1014F; s-kdr M918L; s-kdr M918T; and L932F). No pyrethroid-sensitive genotype was detected. The S431F amino acid substitution conferring resistance to carbamates was detected in 11 of 20 individuals with different pyrethroid-resistance genotypes.

CONCLUSION

Resistance of M. persicae to both pyrethroids and carbamates was detected in nine of 11 populations. High resistance of M. persicae was correlated with mutations of the sodium channel. Sulfoxaflor, flonicamid, and spirotetramat are proposed as effective compounds to control pyrethroid- and carbamate-resistant populations of M. persicae. © 2023 Society of Chemical Industry.

The evolving story of sulfoxaflor resistance in the green peach aphid, Myzus persicae (Sulzer)

BACKGROUND

The green peach aphid, Myzus persicae (Sulzer), is one of the most economically important crop pests worldwide. Insecticide resistance in this pest was first detected over 60 years ago, with resistance in M. persicae now spanning over 80 active ingredients. Sulfoxaflor is a relatively new insecticide that is primarily used to control sap-feeding insects. In 2018 resistance to sulfoxaflor was discovered in field populations of M. persicae in Australia. This study aimed to determine the current distribution and phenotypic levels of sulfoxaflor resistance in Australian clones of M. persicae and to investigate how these patterns relate to clonal type.

RESULTS

For the first time, we show there is low-level resistance (8-26-fold) distributed across Australia, with resistance being detected in aphids collected from approximately 20% of all M. persicae collected and screened. Furthermore, this study shows sulfoxaflor resistance is found in two M. persicae haplotypes, providing evidence that there have been multiple independent evolutionary events which have given rise to sulfoxaflor resistance in this species.

CONCLUSION

These findings have important implications for the chemical control of M. persicae in Australia, especially when considering the broader genetic background of these aphids which are known to harbour a number of other insecticide resistance mechanisms. We recommend continuous monitoring of sulfoxaflor resistance in field populations of M. persicae (in Australia and elsewhere) and further research into the underlying genetic mechanisms conferring resistance to sulfoxaflor in both clonal haplotypes. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

The role of the Bemisia tabaci and Trialeurodes vaporariorum cytochrome-P450 clade CYP6DPx in resistance to nicotine and neonicotinoids

The alkaloid, nicotine, produced by tobacco and other Solanaceae as an anti-herbivore defence chemical is one of the most toxic natural insecticides in nature. However, some insects, such as the whitefly species, Trialeurodes vaporariorum and Bemisia tabaci show strong tolerance to this allelochemical and can utilise tobacco as a host. Here, we used biological, molecular and functional approaches to investigate the role of cytochrome P450 enzymes in nicotine tolerance in T. vaporariorum and B. tabaci. Insecticide bioassays revealed that feeding on tobacco resulted in strong induced tolerance to nicotine in both species. Transcriptome profiling of both species reared on tobacco and bean hosts revealed profound differences in the transcriptional response these host plants. Interrogation of the expression of P450 genes in the host-adapted lines revealed that P450 genes belonging to the CYP6DP subfamily are strongly upregulated in lines reared on tobacco. Functional characterisation of these P450s revealed that CYP6DP1 and CYP6DP2 of T. vaporariorum and CYP6DP3 of B. tabaci confer resistance to nicotine in vivo. These three genes, in addition to the B. tabaci P450 CYP6DP5, were also found to confer resistance to the neonicotinoid imidacloprid. Our data provide new insight into the molecular basis of nicotine resistance in insects and illustrates how divergence in the evolution of P450 genes in this subfamily in whiteflies may have impacted the extent to which different species can tolerate a potent natural insecticide.

Host adaptation and specialization in Tetranychidae mites

Composite generalist herbivores are comprised of host-adapted populations that retain the ability to shift hosts. The degree and overlap of mechanisms used by host-adapted generalist and specialist herbivores to overcome the same host plant defenses are largely unknown. Tetranychidae mites are exceptionally suited to address the relationship between host adaptation and specialization in herbivores as this group harbors closely related species with remarkably different host ranges-an extreme generalist the two-spotted spider mite (Tetranychus urticae Koch [Tu]) and the Solanaceous specialist Tetranychus evansi (Te). Here, we used tomato-adapted two-spotted spider mite (Tu-A) and Te populations to compare mechanisms underlying their host adaptation and specialization. We show that both mites attenuate induced tomato defenses, including protease inhibitors (PIs) that target mite cathepsin L digestive proteases. While Te solely relies on transcriptional attenuation of PI induction, Tu and Tu-A have elevated constitutive activity of cathepsin L proteases, making them less susceptible to plant anti-digestive proteins. Tu-A and Te also rely on detoxification of tomato constitutive defenses. Te uses esterase and P450 activities, while Tu-A depends on the activity of all major detoxification enzymatic classes to disarm tomato defensive compounds to a lesser extent. Thus, even though both Tu-A and Te use similar mechanisms to counteract tomato defenses, Te can better cope with them. This finding is congruent with the ecological and evolutionary times required to establish mite adaptation and specialization states, respectively.

Design, Synthesis, and Insecticidal Evaluation of Neonicotinoids with Conjugated Diene

Neonicotinoid insecticides acting on the insect nicotinic acetylcholine receptors (nAChRs) play an essential role in contemporary pest control. In the present study, a series of novel neonicotinoid analogues with conjugated diene were synthesized. Bioassays indicated that compounds A3 and A12 had LC₅₀ values of 1.26 and 1.24 mg/L against Myzus persicae, respectively, which were comparable to that of imidacloprid (IMI, LC₅₀ = 0.78 mg/L). Density functional theory (DFT) calculations were performed to explain the differences in the insecticidal activities of target compounds. Molecular docking results indicate that compounds A3 and A12 interact favorably with Lymnaea stagnalis AChBP. The hydrolysis experiments confirmed that the stability of compounds A3 and A12 was enhanced in water.

Afidopyropen as a potential tool for Potato leafroll virus management in post-neonicotinoid potato production

Potato leafroll virus (PLRV) has been well managed by neonicotinoids since their widespread adoption in the United States, becoming virtually absent from seed and production fields in the Northwest. However, with increasing interest in discontinuing neonicotinoid usage, there is concern that PLRV could enjoy a resurgence in the absence of effective alternative chemistries. We tested the effects of afidopyropen, an insecticide with novel mode of action, on PLRV transmission and the feeding/probing behavior of its primary vector, the green peach aphid (Myzus persicae [Sulzer]). Afidopyropen foliar sprays decreased PLRV transmission by individual green peach aphids relative to water controls: PLRV acquisition from treated potato plants and subsequent transmission was reduced by 89%, and PLRV inoculation by viruliferous aphids to treated potato plants was reduced by 35%. Although electropenetrograph analyses following 4-h recordings of individual aphids on potato plants showed decreases in the total and mean duration of phloem feeding (E) on plants subject to an afidopyropen treatment relative to water, these only trended toward significance. Taken together, these results suggest treatment with afidopyropen can decrease PLRV transmission in potatoes, but that significant changes in feeding/probing might not occur quickly post-exposure. Overall, while the reductions in transmission were not as dramatic as have been observed following neonicotinoid treatments, afidopyropen may be a useful alternative and should be evaluated in field experiments.

The molecular mechanisms of insecticide resistance in aphid crop pests

Aphids are a group of hemipteran insects that include some of the world's most economically important agricultural pests. The control of pest aphids has relied heavily on the use of chemical insecticides, however, the evolution of resistance poses a serious threat to their sustainable control. Over 1000 cases of resistance have now been documented for aphids involving a remarkable diversity of mechanisms that, individually or in combination, allow the toxic effect of insecticides to be avoided or overcome. In addition to its applied importance as a growing threat to human food security, insecticide resistance in aphids also offers an exceptional opportunity to study evolution under strong selection and gain insight into the genetic variation fuelling rapid adaptation. In this review we summarise the biochemical and molecular mechanisms underlying resistance in the most economically important aphid pests worldwide and the insights study of this topic has provided on the genomic architecture of adaptive traits.

P450-mediated resistance in Myzus persicae (Sulzer) (Hemiptera: Aphididae) reduces the efficacy of neonicotinoid seed treatments in Brassica napus

BACKGROUND

The prophylactic use of seeds treated with neonicotinoid insecticides remains an important means of controlling aphid pests in canola (Brassica napus) crops in many countries. Yet, one of the most economically important aphid species worldwide, the peach potato aphid (Myzus persicae), has evolved mechanisms which confer resistance to neonicotinoids, including amplification of the cytochrome P450 gene, CYP6CY3. While CYP6CY3 amplification has been associated with low-level resistance to several neonicotinoids in laboratory acute toxicity bioassays, its impact on insecticide efficacy in the field remains unresolved. In this study, we investigated the impact of CYP6CY3 amplification on the ability of M. persicae to survive neonicotinoid exposure under laboratory and semi-field conditions.

RESULTS

Three M. persicae clones, possessing different copy numbers of CYP6CY3, were shown to respond differently when exposed to the neonicotinoids, imidacloprid and thiamethoxam, in laboratory bioassays. Two clones, EastNaernup209 and Osborne171, displayed low levels of resistance (3-20-fold), which is consistent with previous studies. However, in a large-scale semi-field trial, both clones showed a surprising ability to survive and reproduce on B. napus seedlings grown from commercial rates of neonicotinoid-treated seed. In contrast, an insecticide-susceptible clone, of wild-type CYP6CY3 copy number, was unable to survive on seedlings treated in the same manner.

CONCLUSION

Our findings suggest that amplification of CYP6CY3 in M. persicae clones substantially impairs the efficacy of neonicotinoid seed treatments when applied to B. napus. These findings highlight the potentially important real-world implications of resistances typically considered to be 'low level' as defined through laboratory bioassays. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Anti-Aphid Polyketides from Streptomyces sp. SA61

Myzus persicae (Sulzer) is a crop pest causing serious economic losses around the world. For many decades, the management of M. persicae has relied heavily on chemical pesticides, resulting in the development of resistance, and new compounds with activity against M. persicae are needed. Five novel polyketides, strekingmycins A-E (1-5), were isolated from Streptomyces sp. SA61. Their structures were determined based on MS, NMR, and X-ray diffraction data. Strekingmycins were active against M. persicae between 4.4 and 9.4 μg/mL.

Comparison of the effectiveness of thiamethoxam and its main metabolite clothianidin after foliar spraying and root irrigation to control Myzus persicae on peach

The green peach aphid, Myzus persicae, is one of the most economically important pests in peach-growing areas around the world. In many countries, the application of insecticides is the main method to control and reduce the population of M. persicae. In this study, we investigated the effects and persistence of thiamethoxam against M. persicae by foliar spraying and root irrigation. The residues of thiamethoxam and clothianidin in peach were determined to assess food safety. The results showed that thiamethoxam treatment significantly reduced the population of M. persicae through foliar spraying and root irrigation. And the persistence of root irrigation on M. persicae was significantly longer than that of spraying. Thiamethoxam and clothianidin were absorbed by the roots, transported to other parts of the plant, and concentrated in the leaves, especially new leaves. The final residues of thiamethoxam and clothianidin in peaches were below the maximum residue limit (MRLs). These results suggested that thiamethoxam is more effective in M. persicae control through root irrigation than foliar spraying. The persistence of root irrigation on M. persicae was significantly longer than that of spraying. These results shed some light upon the control of M. persicae by root irrigation of thiamethoxam.

Impact of the nicotinic acetylcholine receptor mutation R81T on the response of European Myzus persicae populations to imidacloprid and sulfoxaflor in laboratory and in the field

Sulfoxaflor (Isoclast™ active) is a sulfoximine insecticide that is active on a broad range of sap-feeding insects, including species that exhibit reduced susceptibility to currently available insecticides. Colonies of Myzus persicae (green peach aphid) were established from aphids collected in the field from peach (Prunus persica) and nectarine (Prunus persica var. nucipersica) orchards in France, Italy and Spain. The presence of the nicotinic acetylcholine receptor (nAChR) point mutation R81T was determined for all the colonies. Eight of the 35 colonies collected were susceptible relative to R81T (i.e., R81T absent), three of the colonies were found to be homozygous for R81T while 24 colonies had R81T present in some proportion (heterozygous). Sulfoxaflor and imidacloprid were tested in the laboratory against these M. persicae field colonies, which exhibited a wide range of susceptibilities (sulfoxaflor RR = 0.6 to 61, imidacloprid RR = 0.7 to 986) (resistance ratios, RR) to both insecticides. Although sulfoxaflor was consistently more active than imidacloprid against these field collected M. persicae, there was a statistically significant correlation across all colonies between the RRs for imidacloprid and sulfoxaflor (Pearson's r = 0.939, p < 0.0001). However, when a larger group of the colonies from Spain possessing R81T were analyzed, there was no correlation observed for the RRs between imidacloprid and sulfoxaflor (r = 0.2901, p = 0.3604). Thus, consistent with prior studies, the presence of R81T by itself is not well correlated with altered susceptibility to sulfoxaflor. In field trials, sulfoxaflor (24 and 36 gai/ha) was highly effective (~avg. 88-96% control) against M. persicae, demonstrating similar levels of efficacy as flonicamid (60-70 gai/ha) and spirotetramat (100-180 gai/ha) at 13-15 days after application, in contrast to imidacloprid (110-190 gai/ha) and acetamiprid (50-75 gai/ha) with lower levels of efficacy (~avg. 62-67% control). Consequently, sulfoxaflor is an effective tool for use in insect pest management programs for M. persicae. However, it is recommended that sulfoxaflor be used in the context of an insecticide resistance management program as advocated by the Insecticide Resistance Action Committee involving rotation with insecticides possessing other modes of action (i.e., avoiding rotation with other Group 4 insecticides) to minimize the chances for resistance development and to extend its future utility.

Host plants and insecticides shape the evolution of genetic and clonal diversity in a major aphid crop pest

Understanding the spatiotemporal dynamics of pesticide resistance at the landscape scale is essential to anticipate the evolution and spread of new resistance phenotypes. In crop mosaics, host plant specialization in pest populations is likely to dampen the spread of pesticide resistance between different crops even in mobile pests such as aphids. Here, we assessed the contribution of host‐based genetic differentiation to the dynamics of resistance alleles in Myzus persicae, a major aphid pest which displays several insecticide resistance mechanisms. We obtained a representative sample of aphids from a crop mosaic through a suction trap for 7 years and from various crops as a reference collection. We genotyped these aphids at 14 microsatellite markers and four insecticide‐resistant loci, analyzed the genetic structure, and assigned host‐based genetic groups from field‐collected aphids. Four well‐defined genetic clusters were found in aerial samples, three of which with strong association with host‐plants. The fourth group was exclusive to aerial samples and highly divergent from the others, suggesting mixture with a closely related taxon of M. persicae associated with unsampled plants. We found a sharp differentiation between individuals from peach and herbaceous plants. Individuals from herbaceous hosts were separated into two genetic clusters, one more strongly associated with tobacco. The 4‐loci resistance genotypes showed a strong association with the four genetic clusters, indicative of barriers to the spread of resistance. However, we found a small number of clones with resistant alleles on multiple host‐plant species, which may spread insecticide resistance between crops. The 7‐year survey revealed a rapid turn‐over of aphid genotypes as well as the emergence, frequency increase and persistence of clones with resistance to several families of insecticides. This study highlights the importance of considering landscape‐scale population structure to identify the risk of emergence and spread of insecticide resistance for a particular crop.

Overexpression of UDP-glucuronosyltransferase and cytochrome P450 enzymes confers resistance to sulfoxaflor in field populations of the aphid, Myzus persicae

The green peach aphid, Myzus persicae, is a highly damaging, globally distributed crop pest that has evolved multiple resistance to numerous insecticides. It is thus imperative that insecticides that are not strongly compromised by pre-existing resistance are carefully managed to maximise their effective life span. Sulfoxaflor is a sulfoximine insecticide that retains efficacy against M. persicae clones that exhibit resistance to older insecticides. In the current study we monitored the efficacy of sulfoxaflor against M. persicae populations collected in Western Australia, following reports of control failures in this region. We identified clones with low (4-23-fold across multiple independent bioassay experiments), but significant, levels of resistance to sulfoxaflor compared with a reference susceptible clone. Furthermore, we demonstrate that sulfoxaflor resistance can persist after many months of culturing in the laboratory in the absence of insecticide exposure. Resistance was not conferred by known mechanisms of resistance to neonicotinoid insecticides, that act on the same target-site as sulfoxaflor, i.e. the R81T mutation or overexpresssion of the P450 gene CYP6CY3. Rather, transcriptome profiling of multiple resistant and susceptible clones identified the P450 CYP380C40 and the UDP-glucuronosyltransferase UGT344P2 as highly overexpressed (21-76-fold and 6-33-fold respectively) in the resistant clones. Transgenic expression of these genes demonstrated that they confer, low, but significant, levels of resistance to sulfoxaflor in vivo. Taken together, our data reveal the presence of low-level resistance to sulfoxaflor in M. persicae populations in Australia and uncover two novel mechanisms conferring resistance to this compound. The findings and tools generated in this study provide a platform for the development of strategies that aim to slow, prevent or overcome the evolution of more potent resistance to sulfoxaflor.