title: When history repeats itself: exploring the genetic architecture of host-plant adaptation in two closely related lepidopteran species.
abstract: The genus Ostrinia includes two allopatric maize pests across Eurasia, namely the European corn borer (ECB, O. nubilalis) and the Asian corn borer (ACB, O. furnacalis). A third species, the Adzuki bean borer (ABB, O. scapulalis), occurs in sympatry with both the ECB and the ACB. The ABB mostly feeds on native dicots, which probably correspond to the ancestral host plant type for the genus Ostrinia. This situation offers the opportunity to characterize the two presumably independent adaptations or preadaptations to maize that occurred in the ECB and ACB. In the present study, we aimed at deciphering the genetic architecture of these two adaptations to maize, a monocot host plant recently introduced into Eurasia. To this end, we performed a genome scan analysis based on 684 AFLP markers in 12 populations of ECB, ACB and ABB. We detected 2 outlier AFLP loci when comparing French populations of the ECB and ABB, and 9 outliers when comparing Chinese populations of the ACB and ABB. These outliers were different in both countries, and we found no evidence of linkage disequilibrium between any two of them. These results suggest that adaptation or preadaptation to maize relies on a different genetic architecture in the ECB and ACB. However, this conclusion must be considered in light of the constraints inherent to genome scan approaches and of the intricate evolution of adaptation and reproductive isolation in the Ostrinia spp. complex.
authors.affiliation: INRA, UMR CBGP (INRA, IRD, CIRAD, Montpellier SupAgro), Montferrier-sur-Lez, France.
authors.forename: Hermine
authors.initials: H
authors.lastname: Alexandre
authors.forename: Sergine
authors.initials: S
authors.lastname: Ponsard
authors.forename: Denis
authors.initials: D
authors.lastname: Bourguet
authors.forename: Renaud
authors.initials: R
authors.lastname: Vitalis
authors.forename: Philippe
authors.initials: P
authors.lastname: Audiot
authors.forename: Sandrine
authors.initials: S
authors.lastname: Cros-Arteil
authors.forename: Réjane
authors.initials: R
authors.lastname: Streiff
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D054458:Amplified Fragment Length Polymorphism Analysis; D000818:Animals; D001499:Bayes Theorem; D002681:China; D016000:Cluster Analysis; D005602:France; D056426:Genetic Loci / Q000235:genetics; D005819:Genetic Markers; D005843:Geography; D006790:Host-Parasite Interactions / Q000235:genetics*; D009036:Moths / Q000235:genetics*; D011157:Population Dynamics; D060047:Reproductive Isolation; D013045:Species Specificity; D003313:Zea mays / Q000469:parasitology*
chemical_list: D005819:Genetic Markers