Allozyme Variation and Mating System of Three Douglas-fir Stands in Switzerland

1993

25 Lit. Ang.

Unselbständiges Werk

4683

200051410

Ten enzyme systems representing 15 allozyme loci were assayed in seeds (megagametophyte (1N) and embryo (2N) tissues) from 3 Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) populations in Switzerland. The genetic affinity of the Swiss populations to those in the native range was assessed by the use of Nei's genetic distance measure and allozyme data available from a range-wide study of Douglas-fir. All 3 Swiss populations clustered clearly with populations of the coastal variety, which is consistent with their assumed origin. In addition, the Swiss populations had levels of genetic diversity consistent with observations reported for native populations of this variety. In all 3 Swiss populations, estimated proportions of outcrossed offspring were lower than reported for native populations. Because of the high levels of selfing indicated by these low values, special precautions should be taken in using seeds from these stands for reforestation purposes.