There is more than chitin synthase in insect resistance to benzoylureas: molecular markers associated with teflubenzuron resistance in Spodoptera frugiperda

Chitin synthesis inhibitors are successfully used in pest control and an excellent option for integrated pest management programs due to their low non-target effects. However, field-evolved resistance of lepidopteran pests to chitin synthesis inhibitors and the selection of laboratory-resistant strains to these products has been already reported. Therefore, to support efficient resistance management programs it is necessary to expand the knowledge on the resistance mechanisms and potential molecular markers that detect resistant alleles. Teflubenzuron is a chitin synthesis inhibitor used to control the world widely distributed fall armyworm, Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae). Here, we report the selection and inheritance characterization of S. frugiperda strain resistant to teflubenzuron. We also evaluated the cross-resistance to other chitin-synthesis inhibitors and identified single nucleotide polymorphisms (SNPs), which can be used as molecular markers for monitoring the evolution of resistance of S. frugiperda to teflubenzuron. The resistance of the selected strain of S. frugiperda to teflubenzuron was characterized as polygenic, autosomal, and incompletely recessive. The resistance ratio observed was nearly 1,365-fold. Teflubenzuron-resistant strain showed cross-resistance to lufenuron and novaluron, but not to chlorfluazuron. We also detected a set of 72 SNPs that could support monitoring of the resistance frequency to teflubenzuron in field populations. Our data contribute to the understanding of the resistance mechanisms and the inheritance of resistance of S. frugiperda to benzoylureas. We also contribute with candidate markers as tools for monitoring the emergence and spread of teflubenzuron resistance in S. frugiperda.