LACK OF ALLOZYMIC VARIATION IN DISJUNCT NEWFOUNDLAND POPULATIONS OF RED PINE (PINUS-RESINOSA)

Disjunct, geographically isolated populations of red pine (Pinus resinosa Ait.) on the island of Newfoundland were investigated by enzyme electrophoresis to determine if these populations were genetically distinct from a range-wide sample of mainland populations. Genetic variation at 23 putative gene loci from 12 enzyme systems was assayed by cellulose acetate gel electrophoresis. Each of the 96 trees sampled was monomorphic for all enzyme gene loci assayed, and no genetic differentiation between Newfoundland and mainland populations was detected. The striking lack of genetic variation at enzyme gene loci in red pine has been confirmed for the most isolated populations at the extreme northeastern margins of its range.