Résumé
Plant pararetroviruses integrate serendipitously into their host genomes. The banana genome harbors integrated copies of bananastreak virus (BSV) named endogenous BSV (eBSV) that are able to release infectious pararetrovirus. In this investigation,we characterized integrants of three BSV species—Goldfinger (eBSGFV), Imove (eBSImV), and Obino l’Ewai (eBSOLV)—in theseedy Musa balbisiana Pisang klutuk wulung (PKW) by studying their molecular structure, genomic organization, genomiclandscape, and infectious capacity. All eBSVs exhibit extensive viral genome duplications and rearrangements. eBSV segregationanalysis on an F1 population of PKW combined with fluorescent in situ hybridization analysis showed that eBSImV, eBSOLV,and eBSGFV are each present at a single locus. eBSOLV and eBSGFV contain two distinct alleles, whereas eBSImV has two structurallyidentical alleles. Genotyping of both eBSV and viral particles expressed in the progeny demonstrated that only one allelefor each species is infectious. The infectious allele of eBSImV could not be identified since the two alleles are identical. Finally, wedemonstrate that eBSGFV and eBSOLV are located on chromosome 1 and eBSImV is located on chromosome 2 of the referenceMusa genome published recently. The structure and evolution of eBSVs suggest sequential integration into the plant genome,and haplotype divergence analysis confirms that the three loci display differential evolution. Based on our data, we propose amodel for BSV integration and eBSV evolution in the Musa balbisiana genome. The mutual benefits of this unique host-pathogenassociation are also discussed.