Next generation sequencing reveals potential for the development of insecticide resistance and cross-resistance in Drosophila suzukii (Diptera: Drosophilidae)

ABSTRACT: The goal of this study is to proactively assess the risk of insecticide resistance development by determining susceptibility of field-collected D. suzukii and their response to insecticide treatment at the transcriptome level using next-generation sequencing technology. Methods:LC50 values were calculated for zeta-cypermethrin, spinosad, malathion treated D. suzukii field-collected and lab-reared populations. LC50 dosage survived and untreated (10 individuals per replicate) field-collected and lab reared D.suzukii transcript profiles were generated by RNA sequencing, in triplicate, using Illumina NextSeq 500. The 24 samples (paired-end reads, including replicates) were independently mapped onto the D. suzukii genome (SpottedWingFlybase v.1) by using TopHat followed by Cufflinks to estimate the expression values of the transcripts in FPKM (Fragments Per Kilobase per Million mapped reads) with the Cuffdiff 2 default geometric normalization. Differentially expressed genes (FDR < 0.05 after Benjamini-Hochberg correction for multiple-testing) were identified for insecticide-treated or untreated control for either (1) lab-reared populations or (2) field-collected populations. Results: As an approach to proactively assess the risk of insecticide resistance development, we determined the LC50 (lethal concentration, 50%) values of commonly used insecticides zeta-cypermethrin, spinosad, and malathion against laboratory-reared and field-collected D. suzukii populations. The LC50 values were significantly higher in field-collected populations when compared to lab-reared populations, indicating that field populations are less susceptible to these insecticides. Furthermore, we used RNA sequencing to analyze the response of D. suzukii at the transcriptome level upon treatment with the same three insecticide classes that are used in our bioassays. We identified differentially expressed genes (DEGs) in D. suzukii that survived LD50 doses of zeta-cypermethrin, spinosad, and malathion and gene classes that are overrepresented in DEGs. We observed that a high number of significantly DEGs are involved in detoxification and reduced cuticular penetration, especially in field population, thus providing potential molecular mechanisms for the higher LC50 values for field-collected population. Conclusion: Our study identified a high number of metabolic detoxification genes that are induced in field-collected D. suzukii upon insecticide treatment and a high degree of overlap when examining the lists of genes that are induced when D. suzukii is treated with three commonly used insecticides. Based on our results, we conclude that there is a substantial risk of insecticide resistance and cross-resistance development in D. suzukii in the field.

ORGANISM(S): Drosophila suzukii

PROVIDER: GSE73595 | GEO | 2016/09/23

SECONDARY ACCESSION(S): PRJNA297377

REPOSITORIES: GEO