Isozyme variation among and within North Atlantic species of Papaver sect. Meconella (Papaveraceae) and taxonomic implications

Abstract

The high-ploid species Papaver dahlianum, P. lapponicum, P. laestadianum and P. radicatum were compared by means of enzyme electrophoresis. The diploid P. alpinum from the Alps and garden material of the assumed diploid P. croceum from Asia were also included. The results are compared with those of previous morphological and cytological investigations. Generally, only small differences were found among the species. The maintenance of 13 sub-species of P. radicatum as published from the Nordic area was not supported. The octoploid P. laestadianum was nearly identical to the decaploid P. radicatum and inclusion in P. radicatum is justified. The octoploid P. lapponicum was also very similar to P. radicatum and inclusion of it in the latter should be considered. The most distinct of the taxa was the decaploid P. dahlianum, and the maintenance of two subspecies, ssp. polare and ssp. dahlianum can be defended. A hybrid origin of P radicatum (10x) from P. lapponicum (8x) and P. alpinum (2x), and of P. dahlianum (10x) from P lapponicum and P. croceum (2x) has been proposed, but a more likely explanation might be that P. dahlianum, P. radicatum and P. lapponicum have all arisen by polyploidization from closely related diploids without hybridization. © 2003 The Linnean Society of London.