Fig. 3. Phenotypic variation for plants in the field and grown in a common garden assay. Boxes and whiskers show among microsite variation for each site. Sites are ordered by mean frond area and are consistent for the four panels. A&C. Phenotypic variation in the field. Phenotype was measured on 10 plants per microsite and averaged to produce a single estimate per microsite. B&D. Phenotypic variation in the common garden. Phenotype was measured on 10 plants in each of two replicate flasks for each microsite and averaged to produce a single estimate per microsite.
Despite the overall marked decrease in phenotypic variation, variation among sites and microsites persisted in the common garden assay. Frond area varied significantly among sites (F33,68=1.71, p=0.03) and among microsites within sites (F68,102=2.15, p=0.0002) with roughly twice as much variation within sites among microsites, than among sites (Table 2). Similarly, root length varied significantly among sites (F33,68=1.98, p=0.009) and among microsites within sites (F68,102=1.44, p=0.05), with roughly equal amounts of variation among sites and among microsites (Table 2).
Table 2. Variation in frond area (mm2) and root length (mm) among plants grown in a common garden assay. Ten individual plants were measured in each of two replicate flasks for each of three microsite, for 34 sites situated broadly across southern Quebec.