Bioarchaeological Insights into the Process of Domestication of Grapevine (Vitis vinifera L.) during Roman Times in Southern France

Abstract

Grapevine (Vitis vinifera), one of the most important fruit species in the Classical Mediterranean world, is thought to have been domesticated first in South-Western Asia, during the Neolithic. However, the domestication process remains largely unknown. Crucial unanswered questions concern the duration of the process (rapid or slow?) and the related geographical area (single or multiple-origins?). Seeds from domesticated grapevine and from its wild ancestor are reported to differ according to shape. Our work aims, first, to confirm this difference and secondly to identify the extent of domestication in the grapes cultivated by Romans in Southern France during the period 50 BCE–500 CE. We had the opportunity to analyze uncharred waterlogged grape pips from 17 archaeological sites. Based on an extended reference sample of modern wild grapevines and cultivars our work shows that both subspecies can be discriminated using simple measurements. The elongation gradient of the pip’s body and stalk may be regarded as an indicator of the strength of the selection pressures undergone by domesticated grapes. Grapevines cultivated during the Roman period included a mix of morphotypes comprising wild, intermediate and moderately selected domesticated forms. Our data point to a relative shift towards more selected types during the Roman period. Domestication of the grapevine appears to have been a slow process. This could result from the recurrent incorporation into cultivation of plants originating from sexual reproduction, when grape cultivation essentially relies on vegetative propagation.

The Domestication Syndrome in Phoenix dactylifera Seeds: Toward the Identification of Wild Date Palm Populations

“…soybean [61]) and fruit trees (e.g. Caimito [37], olive tree [35] and grapevine [36]). It has been shown to be correlated with an increase in fruit size [39–41].…”

“…in the olive tree [17,35], grapevine [36] or caimito [37]) and detect or suspect feral individuals [17,38]. Focusing on seeds rather than other plant organs is interesting because seeds are easily sampled and stored, and keep well.…”

Identification of inter- and intra-species variation in cereal grains through geometric morphometric analysis, and its resilience under experimental charring

“…Morphometric methods have been used to address intra-species variation for other archaeobotanical remains such as grape pips (Bouby et al, 2013;Terral et al, 2010), and Ros et al have recently investigated grain shape variation between sub-species and 70 varieties of barley (Ros et al, 2014). This type of investigation is best achieved through the analysis of variation in modern material where the species and source of the grain is already known, before attempts are made to apply the method to archaeologically preserved material where taxonomic identity must be inferred from the remains themselves.…”

The limits and potential of paleogenomic techniques for reconstructing grapevine domestication

“…Later events in the history of grape domestication are equally ambiguous, including a possible secondary domestication event in Western Europe (Arroyo-García et al, 2006) or introgression of Western sylvestris into introduced varieties of sativa (Myles et al, 2011), millennial-scale changes in vinicultural practices and vineyard management, and the origins of varietal lineages. These processes are currently examined by archaeobotanical studies using image analysis techniques (Terral et al, 2010), in which morphometric features distinguish sylvestris and sativa cultivars, leading to insights on ancient grapevine cultivation (Bouby et al, 2013;Ucchesu et al, 2015). Such morphometric approaches can be complemented by aDNA from archaeological samples, providing unparalleled snapshots of past genetic diversity to understand these complex processes.…”