Competitive replacement of the native Vitis and Hedera taxa by invasive aliens: morphological, cytological and molecular evidences

Abstract

We describe here case studies of two woody climber species native to the broadleaf forests of the Carpathian basin. Wild grape (Vitis sylvestris C.C.Gmel.), considered to be one of the ancestors of the domesticated grapevine (Vitis vinifera L.) became a highly threatened species since the introduction of the American grape species as rootstocks for grapevine. Among these, especially, Riparian grape (Vitis riparia Minchx.) escaped from the wine yards and by invading the natural habitats replaced the autochthonous wild grape. In consequence of the competitive exclusion Vitis sylvestris suffered a strong withdrawal along its native habitats. 20 morphological traits, including leaf shape and trichome structure were studied to tackle evidence of the introgressive hybridization among the alien and native taxa. Most of the studied Hungarian habitats were already dominated by hybrid specimens of Vitis taxa. Molecular analysis based on 8 nuclear microsatellites markers supported the morphological results.