Lack of Known Target-Site Mutations in Field Populations of Ostrinia furnacalis in China from 2019 to 2021

Abstract

The Asian corn borer, Ostrinia furnacalis (Guenée) (Lepidoptera; Pyralidae), is one of the most destructive insect pests of corn, for which chemical insecticides have been the primary method of control, especially during outbreaks. Little information is currently available on the status of insecticide resistance and associated mechanisms in O. furnacalis field populations. Invasions and outbreaks of Spodoptera frugiperda in China in recent years have increased chemical application in corn fields, which adds to the selection pressure on O. furnacalis. This study was conducted to estimate the risk of insecticide resistance by investigating the frequency of insecticide resistant alleles associated with target site insensitivity in field populations of O. furnacalis. Using the individual-PCR genotype sequencing analysis, none of the six target-site insecticide resistant mutations were detected in O. furnacalis field populations collected from 2019 to 2021 in China. These investigated insecticide resistance alleles are common in resistant Lepidoptra pests and are responsible for resistance to pyrethroids, organophosphorus, carbamates, diamide, and Cry1Ab. Our results support the low insecticide resistance status in field O. furnacalis populations and betokens the unlikely development of high resistance mediated by the common target-site resistance alleles. Additionally, the findings would serve as references for further efforts toward the sustainable management of O. furnacalis.

Keywords: Ace 1 gene; L1014F mutation; RyR gene; diamide insecticides; genotype; insecticide susceptibility.

Figure 1

Comparison of the amino acid sequences of target genes between Ostrinia furnacalis and other species to locate the amino acid site of resistance mutation. (A) For A201S mutation, Ace1 gene amino acid sequence of O. furnacalis was compared with Chilo suppressalis [18]; (B) for F331Y/W mutation in Acetylcholinesterase 1 gene, amino acid sequence of O. furnacalis was compared with Tetranychus evansi [39]; (C) for I4790M mutation in Ryanodine receptors gene (RyR), amino acid sequence of O. furnacalis was compared with Plutella xylostella [24]; (D) for G4946E mutation in RyR gene, amino acid sequence of O. furnacalis was compared with Plutella xylostella [23]; (E) for L1014F mutation in voltage-gated sodium channel (VGSC) gene, amino acid sequence of O. furnacalis was compared with Musca domestica [28]; (F) for 234-site Y insert in ABC transporter (ABCC2) gene, amino acid sequence of O. furnacalis was compared with Bombyx mori [37].

Figure 2

PCR amplification of DNA containing the resistance mutations. We display one figure per mutation with amplification size, which indicates that the DNA fragments containing the corresponding desired mutations were amplified as expected: (A) A201S and F331Y/W in Acetylcholinesterase Ace1; (B) L1014F in voltage-gated sodium channel (VGSC); (C) G4946E in ryanodine receptors (RyR); (D) I4790M in RyR; and (E) 234Y insertion in ABC transporter (ABCC2).

Figure 3

Representative chromatograms of the insecticide resistance mutations examined in Asian corn borer collected in 2019–2021 from China. Black wireframe indicates the site of the examined mutation in the DNA sequence and the nucleotide codon (amino acid) of the examined mutation in all tested samples: (A) for the A201S mutation; (B) for F331Y/W; (C) for the G4946E mutation; (D) for the I4790M mutation; (E) for the L1014F mutation; and (F) for the 234Y insertion.