An investigation of large-leaved Gunnera L. (Gunneraceae) grown outside in Britain and Ireland

Abstract

A molecular investigation of large-leaved Gunnera growing outside in Britain and Ireland was conducted. Two low-copy nuclear CYCLOIDEA-like genes (CYC-like 1 and CYC-like 2) and two chloroplast DNA regions (matK and psbD-trnT) were sequenced for 271 samples of Gunnera. While it was confirmed that genuine G. tinctoria is growing both in cultivation and in the wild, the results support recently published morphological and historical findings that the species G. manicata appears no longer to be present in Britain and Ireland. Instead, the plant under this name is G. × cryptica, a hybrid between G. manicata and G. tinctoria. The implication of this discovery for legislation on invasive non-native species where G. manicata and G. tinctoria are listed is explored.