Population differentiation in lodgepole pine, Pinus contorta spp. latifolia: a discriminant analysis of allozyme variation

Abstract

Seeds from 17 populations representing most of the range of lodgepole pine in the Yukon and British Columbia were analyzed for electrophoretically demonstrable variation in 16 proteins coded by 23 genetic loci. Consistent with that reported on genetic variation in this conifer, on the average, 64% of the loci per population were polymorphic, and expected and observed heterozygosity per population were 0.165 and 0.174, respectively. Univariate F-ratio tests for homogeneity among populations indicated genetic differentiation (p < 0.05) at six loci. Two significant (p < 0.05) canonical discriminant functions accounted for 38% of the total variance in the 20 polymorphic loci. A rich structure of genetic variation associated with geography was revealed. Both latitude and altitude appeared to be important, with northern populations exhibiting a greater extent of genetic differentiation.Key words: allozymes, electromorphs, populations, Pinus, lodgepole pine.