Plasticity: Environmental Contribution (E)
The proportion of NSC that trees put into starch vs. sugar is a plastic
trait by both metrics of plasticity, RDPI and S (Table 2,
RDPIproportion = 0.50, Sproportion =
0.75). This plastic variation is largely attributable to the effect of
garden, which explains 97% of total plasticity (equation 7; Table 2,
Figure 3). On average, Corvallis has higher sugar concentrations and
lower starch concentrations, while Clatskanie has higher starch
concentrations and lower sugar concentrations (Figures 3B & S2, Table
1). This pattern is reflected in the proportion of NSC stores in starch,
where the proportion of starch to total stores in Corvallis is 50% more
than in Clatskanie (Figure 3B). Thus, there is a clear difference in the
degree to which total stores are partitioned between sugar and starch
within each garden.
In contrast, total NSC stores are only considered environmentally
plastic by one metric (RDPITNC = 0.03,
STNC = 0.43). Only 54% of the plastic variation
(S ) measured is explained by environment, while the rest is
attributed to GxE effects. Thus, we find high genetic variation in TNC
across the gardens, but low plasticity and almost no difference between
the two gardens in average total NSC concentrations
(Δgarden = 0.5 mg•g-1, Table 1, Figure 3A).