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The goal of this work was to explore the possibility (1) of carrying out both morphogeometric and archaeological DNA analyses on the same grape pips and (2) of comparing different molecular markers to reveal DNA variation, namely Simple Sequence Repeats (SSRs) and Single Nucleotide Polymorphisms (SNPs). We focused on waterlogged seeds originating from three Roman and one medieval archaeological sites in France. Our first results indicate that taking photographs of pips is not detrimental to the preservation of DNA, provided a specific protocol is respected. Regarding the genetic markers, obtaining reliable information in sufficient quantity proved very difficult using SSRs. SNPs have a much more interesting potential, providing greater success rates and reliability. Here in four archaeological pips we studied 842 SNPs, derived from known polymorphisms in several genes, including one gene related to sex. Phylogenies built using these genetic markers indicate that three pips from the Roman site of Gasquinoy are close to modern wild grapevines and/or the female group, while the only medieval pip from Colletière is hermaphrodite and close to the modern cultivated group. Morphogeometrical results are in agreement with these findings. We conclude that the combined use of SNP markers and morphogeometry is promising for deciphering the intricate history of grapevine domestication. [ABSTRACT FROM AUTHOR]

The scope and ambition of biomolecular archaeology is undergoing rapid change due to the development of new 'next generation' sequencing (NGS) methods for analysis of ancient DNA in archaeological specimens. These methods have not yet been applied extensively to archaeobotanical material but their utility has been demonstrated with desiccated, waterlogged and charred remains. The future use of NGS is likely to open up new areas of investigation that have been difficult or impossible with the traditional approach to aDNA sequencing. Species identification should become more routine with archaeobotanical explants, not just with charred grain but with most if not all species likely to be encountered in an archaeobotanical setting. Distinctions between different subspecies groups such as cereal landraces will also be possible in the near future. Phenotypic characterization, in which aDNA sequencing is used to infer the biological characteristics of an archaeological specimen, will become possible, improving our understanding of traits such as flowering behaviour of cereals, and when combined with studies of preserved RNA and protein will enable complex phenotypes such as environmental tolerance and nutritional quality to be assessed. The sequencing of entire ancient plant genomes is also likely to have significant impact. As with past studies of ancient plant DNA, realization of the new potential provided by NGS will require productive collaboration between archaeologists and geneticists within the archaeobotanical research community. [ABSTRACT FROM AUTHOR]

Lagenaria siceraria (Molina) Standl. (bottle gourd) is pantropic and displays large variation in fruit and seed shape. Two subspecies are currently recognized: the African L. siceraria ssp. siceraria and the Asian L. siceraria ssp. asiatica. The Asian type of bottle gourd belongs to the earliest domesticated plants in the Americas. In Europe, bottle gourd only appears with some frequency from the Roman period onwards. The paper is the study of ancient DNA (aDNA) and seed morphology of one almost complete bottle gourd fruit from the Roman site of Oedenburg/Biesheim-Kunheim, France (1st century a. d.), and from individual seed finds from the Roman vicus of Petinesca-Vorderberg, Switzerland (3rd century a. d.), both recovered from waterlogged layers. Width and length measurements of seeds show large variation. Based on the index of width to length, seeds from both sites differ significantly ( p < 0.0001 Mann-Whitney) suggesting that there were different variants present north of the Alps. Genetically, the bottle gourd fruit from Roman Oedenburg/Biesheim-Kunheim and one commercial cultivar L. siceraria cv. 'Herkuleskeule' are of Asian origin as identified by three Asian and African specific chloroplast markers. These results support an early and long-lasting presence of the Asian type of domestic bottle gourd in Europe. No chloroplast markers were found in the seeds from Petinesca-Vorderberg. However preserved nuclear high copy 5.8S rDNA fragments correctly matched to Cucurbitaceae, further supporting the evidence for preservation of DNA in waterlogged plant remains. [ABSTRACT FROM AUTHOR]