Unraveling the population structure of Diatraea saccharalis (Fabricius) (Lepidoptera: Crambidae) in Argentina

FOGLIATA, S.; PERERA, M. F.; ALVES-PEREIRA, A.; ZUCCHI, M.I.; MURÚA, M.G.

ENTOMOLOGIA EXPERIMENTALIS ET APPLICATA

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2022

0013-8703

Diatraea saccharalis (Fabricius) (Lepidoptera: Crambidae) is one of the major lepidopteranpests throughout the Western Hemisphere. In Argentina, it causes significantlosses mainly in sugarcaneand corn. Previous studies determined the existence of reproductive incompatibilities betweenpopulations from Buenos Aires and Tucumán from different host plants; however,the genetic basis of this incompatibility is still unknown. As theeffectiveness of pest control programs mainly depends on strategies thatminimize the risk of favoring insecticide-resistant genotypes, estimating thelevel of mating between genotypes is therefore important to monitor and manageresistance. The aim of this study was to characterizethe genetic structure of D. saccharalis populations collected from different hosts andregions in Argentina, comparing with those from Brazil, through Cytochrome C Oxidase Subunit I (COI) analysis and NextGeneration Sequencing (NGS). The COI analysis showed a haplotypic diversity of 0.8 and a nucleotide diversity of0.0058. Analysis of Molecular Variance revealed greater variation withinpopulations than among them. The 17 haplotypes detected were linked in a singleparsimony network that did not reveal clusters based on geography or hostplants. A total of 4,549 Single Nucleotide Polymorphism were obtained throughNGS. Out of the 2,349 outlier loci, 84 showed similarities with previouslycharacterized proteins. The coefficient of inbreeding showed evidence of bothrandom matings as well as some degree of selection. The fixation index values showed high genetic variation between Argentineanand Brazilian populations; however, there was no clear trend based on distanceor hosts. Similarly, the Discriminant Analysis of Principal Components revealedthree separate groups: one Brazilian and two Argentinean. Results generatedimportant clarifications on the population genetic structure of D. saccharalis in South America which,provide information about routes of dispersal and the development of suitable managementstrategies.