Fig. 3. a) Norm of reaction plots illustrating the effects of
ploidy level and defoliation on net photosynthesis (mean ± SE) in
well-watered trees. The left panel represents values averaged across
genotypes from the same ploidy level when defoliated or not defoliated.
Model results above the left panel do not account for genotypic
variation. The right panel represents mean response of eight different
diploid and triploid genotypes when defoliated or not defoliated.
Identical genotypes of both defoliation treatments are shown next to
each other with identical color shades. Model results above the right
panel account for genotypic variation. Only values of model variables
with P ≤ 0.100 are shown. Data points are horizontally jittered to
reduce overlapping. b) Photosynthesis vulnerability curves of
defoliated and undefoliated diploid and triploid genotypes. Red trends
were generated based on back-transformed means of ln-transformed
genotype values for each of the curve-fitting parameters
(A max, b and c ). Transformation of
genotype parameters lessened the undue influence of outlier values. Thin
curves represent untransformed, individual genotypes. The impact of
ploidy, defoliation and their interaction on the curve parametersA max, b and c was tested in models
accounting for genotypic differences. Only values of model variables
with P ≤ 0.100 are shown.