Historical reconstruction of a relictual population of wild grapevines (Vitis vinifera SSP sylvestris Gmelin Hegi) in a floodplain forest of the upper Seine valley France
Arnold C; Schnitzler A; Parisot C; Maurin A
River Research and Applications
Wild grapevine (Vitis vinifera ssp sylvestris) is considered to be nearly extinct in its western range as a result of the expansion of American diseases combined with drastic hydraulic works in the region. In such a context the discovery of a population of 120 individuals offered an excellent opportunity to evaluate the status of the plant at the current edge of its western range. We focussed on the distribution patterns and the reconstruction of the history of the population through a combination of ecological and genetic data.\n\nFifty-one individual plants present in a forest plot of 9.72?ha were studied. For each individual geographical morphological and growth strategy data were collected. Individuals were genotyped at 14 SSR loci.\n\nMost grapevines were clumped and their density varied between forest plots with different management over the past few centuries. Overall the number of stems possessed by each plant ranged from one to nine. Heights varied from 14 to 24?m with diameter ranging from 0.9 to 4.6?cm (mean?=?2.4?cm).\n\nThe analysis of the genetic data showed that (i) no cultivar or rootstocks were present in the population; (ii) out of 57 individuals considered in this study six were clones; and (iii) all 14 loci were polymorphic. Six groups were shown to be significantly related.\n\nIn spite of a relatively high-genetic diversity the population is currently at a critical state at the local scale because of the low chances of seedling survival for more than 1 year. The clones were also directly destroyed by human management.\n\nThe ideal way to improve the status of the wild grapevine in the Bassée Forest would be to re-create zones of erosion as well as to create a strict conservation area or reserve encompassing the entire region.