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bioRxiv · 10.1101/2024.01.16.575855

Plant kleptomaniacs: geographic genetic patterns in the amphi-apomictic Rubus ser. Glandulosi (Rosaceae) reveal complex reticulate evolution of Eurasian brambles

Abstract

Rubus ser. Glandulosi represents a unique model of geographic parthenogenesis on a homoploid (4x) level. We employed double digest restriction-site associated DNA sequencing (ddRADseq) in 587 individuals of different Rubus taxa and modelling of suitable climate to characterize evolutionary and phylogeographic patterns and shed light on the geographic differentiation of apomicts and sexuals. Six ancestral species were identified that contributed to the contemporary gene pool of R. ser. Glandulosi. While sexuals were introgressed from R. dolichocarpus and R. moschus in West Asia and from R. ulmifolius agg., R. canescens and R. incanescens in Europe, apomicts were characterized by alleles of R. subsect. Rubus. Gene flow between sexuals and apomicts was also detected, as well as occasional hybridization with other taxa. We hypothesize that sexuals survived the last glacial period in several large southern refugia, whereas apomicts were mostly restricted to southern France from whence they quickly recolonized Central and Western Europe. The secondary contact of sexuals and apomicts was probably the principal factor that established geographic parthenogenesis in R. ser. Glandulosi. Sexual populations are not impoverished in genetic diversity along their borderline with apomicts and maladaptive population genetic processes likely did not shape the geographic patterns. HighlightsO_LIGeographic parthenogenesis in Rubus ser. Glandulosi is caused by secondary contact C_LIO_LIReticulate evolution in Eurasian brambles is more extensive than expected C_LIO_LIAt least six species contributed to the evolution of Rubus ser. Glandulosi C_LIO_LIExtinct ancestors gene pool is associated with apomixis C_LI O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=79 SRC="FIGDIR/small/575855v1_ufig1.gif" ALT="Figure 1"> View larger version (51K): org.highwire.dtl.DTLVardef@a25ccforg.highwire.dtl.DTLVardef@17b1a5corg.highwire.dtl.DTLVardef@ffa036org.highwire.dtl.DTLVardef@6f6e0e_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphical abstractC_FLOATNO C_FIG

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Sochor, M., Sarhanova, P., Duchoslav, M., Konecna, M., Hrones, M., Travnicek, B.. 2024-01-17. Plant kleptomaniacs: geographic genetic patterns in the amphi-apomictic Rubus ser. Glandulosi (Rosaceae) reveal complex reticulate evolution of Eurasian brambles. https://doi.org/10.1101/2024.01.16.575855

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