Unraveling the population structure of the sugarcane borer, Diatraea saccharalis , in Argentina

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

ENTOMOLOGIA EXPERIMENTALIS ET APPLICATA

WILEY-BLACKWELL PUBLISHING, INC

Año: 2022

0013-8703

Diatraea saccharalis (Fabricius) (Lepidoptera: Crambidae) is one of the major lepidopteran pests throughout the Western Hemisphere. In Argentina, it causes significantlosses mainly in sugarcane (Saccharum officinarum L.) and corn (maize, Zea mays L.)(both Poaceae). Previous studies determined the existence of reproductive incompatibilities between populations from Buenos Aires and Tucumán from different hostplants; however, the genetic basis of this incompatibility is still unknown. As the effectiveness of pest control programs mainly depends on strategies that minimize the riskof favoring insecticide-resistant genotypes, estimating the level of mating betweengenotypes is important to monitor and manage resistance. The aim of this study wasto characterize the genetic structure of D. saccharalis populations collected from various hosts and regions in Argentina, comparing with those from Brazil, through cytochrome c oxidase subunit I (COI) analysis and next-generation 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 within populationsthan among them. The 17 haplotypes detected were linked in a single parsimony network that did not reveal clusters based on geography or host plants. In total, 4549single nucleotide polymorphism markers (SNPs) were obtained through NGS. Out ofthe 2349 outlier loci, 84 showed similarities with previously characterized proteins.The coefficient of inbreeding showed evidence of random matings as well as somedegree of selection. The fixation index values showed high genetic variation betweenArgentinean and Brazilian populations; however, there was no clear trend based ondistance or hosts. Similarly, the discriminant analysis of principal components revealed three separate groups: one Brazilian and two Argentinean. Results generatedimportant clarification of the population genetic structure of D. saccharalis in SouthAmerica, which provides information about routes of dispersal and the developmentof suitable management strategies