LACK OF DETECTABLE ISOZYME VARIABILITY IN BRITISH POPULATIONS OF POTAMOGETON EPIHYDRUS (POTAMOGETONACEAE)

Outside North America Potamogeton epihydrus Raf. is confined to two ar eas of Britain. An investigation of British material from apparently n ative sites in the Outer Hebrides and from a canal in northern England (where it is believed to be introduced) revealed only a single isozym e genotype. Ten putative loci were resolved. The IDH phenotype was uni form and three-banded, consistent with heterozygosity (possibly caused by a duplicated locus or preserved by clonal growth). All other enzym e loci were homozygous. (C) 1998 Elsevier Science B.V.