DOI: 10.5061/dryad.77148
title: Data from: Historical collections reveal patterns of diffusion of sweet potato in Oceania obscured by modern plant movements and recombination

description: The history of sweet potato in the Pacific has long been an enigma.
 Archaeological, linguistic and ethnobotanical data suggest that
 prehistoric human-mediated dispersal events contributed to the
 distribution in Oceania of this American domesticate. According to the
 “tripartite hypothesis”, sweet potato was introduced into Oceania from
 South America in pre-Columbian times, and was then later newly introduced,
 and diffused widely across the Pacific, by Europeans via two historically
 documented routes from Mexico and the Caribbean. Although sweet potato is
 the most convincing example of putative pre-Columbian connections between
 human occupants of Polynesia and South America, the search for genetic
 evidence of pre-Columbian dispersal of sweet potato into Oceania has been
 inconclusive. Our study attempts to fill this gap. Using complementary
 sets of markers (chloroplast and nuclear microsatellites), and both modern
 and herbarium samples, we test the tripartite hypothesis. Our results
 provide strong support for prehistoric transfer(s) of sweet potato from
 South America (Peru-Ecuador region) into Polynesia. Our results also
 document a temporal shift in the pattern of distribution of genetic
 variation in sweet potato in Oceania. Later re-introductions, accompanied
 by recombination between distinct sweet potato genepools, have reshuffled
 the crop’s initial genetic base, obscuring primary patterns of diffusion
 and at the same time giving rise to an impressive number of local
 variants. Moreover, our study shows that phenotypes, names and neutral
 genes do not necessarily share completely parallel evolutionary histories.
 Multidisciplinary approaches thus appear necessary for accurate
 reconstruction of the intertwined histories of plants and humans.
description: nuclear SSR
 dataNuclear genetic data of
 the samples used in the present study and obtained for the eleven nuclear
 microsatellite loci (J263, J315E, J522A, J116a, Ib297, J260A, J1809E,
 IbR16, IbC5, J544b, IbS11). Sheet 1 provides nuclear data of the samples
 collected in ex situ collections (in total 890 samples) and sheet 2, the
 genetic data obtained for the herbarium specimens (41 specimens in total).
 For hexaploids, we can obtain from 1 to 6 peaks or bands (6 alleles) per
 locus. Allelic composition (from allele 1 to allele 6) is then provided
 for each accession. The sheet 3 provides passeport data of all the
 accessions, referenced in the previous sheets 1 and 2 by their "Dryad
 number": - for ex situ samples (from line 1 to 891), it includes
 names of ex situ collections, full geographical origin data and local
 landrace names. - for herbarium specimens (from line 892 to line 933), it
 includes herbarium codes, geographical origin, dates of collection and
 collector names.chloro SSR
 dataGenetic data obtained
 for the six chloroplast microsatellite loci ccmp2 (or ibcp4), ntcp28 (or
 ibcp31), ibcp5, ibcp10, ibcp8 and ntcp26 for herbarium specimens (57
 specimens in total; sheet 1) and samples collected in ex situ collections
 (in total 1153 samples; sheet 2). Passeport data of all accessions are
 provided along genetic results: - for herbarium specimens, it includes
 herbarium codes, geographical origin, dates of collection, collector names
 along with genetic data, ie, allele code for each locus, haplotype code
 and cp lineage (1 or 2). - for ex situ samples, it includes names of ex
 situ collections, full geographical origin data and local landrace names,
 along with genetic data, ie, allele code for each locus, haplotype code
 and cp lineage (1 or 2)Genetic data obtained for the six chloroplast
 microsatellite loci ccmp2 (or ibcp4), ntcp28 (or ibcp31), ibcp5, ibcp10,
 ibcp8 and ntcp26 for herbarium specimens (57 specimens in total; sheet 1)
 and samples collected in ex situ collections (in total 1153 samples; sheet
 2). Passeport data of all accessions are provided along genetic results: -
 for herbarium specimens, it includes herbarium codes, geographical origin,
 dates of collection, collector names along with genetic data, ie, allele
 code for each locus, haplotype code and cp lineage (1 or 2). - for ex situ
 samples, it includes names of ex situ collections, full geographical
 origin data and local landrace names, along with genetic data, ie, allele
 code for each locus, haplotype code and cp lineage (1 or
 2).chloro
 SSR data .xls