Germination rate depends on seed origin, seed type, and seed
weight:
There was no evidence for local adaptation at HD or HR for either
cleistogamous or chasmogamous seeds (Fig. 3A). However, germination did
depend on seed origin: at HD, nonlocal seeds sourced to the north of the
garden significantly outperformed both local (HD) and nonlocal seeds
sourced to the south of the garden (P < 0.001). At HR,
nonlocal seeds sourced to the north significantly outperformed nonlocal
seeds sourced to the south of the garden (P = 0.015), but local (HR)
seed performance was not significantly different from either nonlocal
seed group. Models for each pairwise combination between nonlocal source
populations and common garden revealed the specific differences in
germination by source population (Appendix C).
At both gardens, cleistogamous seeds significantly outperformed
chasmogamous seeds (P 0.003; Fig. 3A), and seed weight was a significant
positive predictor of germination (P < 0.001; Fig. 3B;
Appendix H, Table 1). Despite this, cleistogamous seeds were universally
lighter weight than chasmogamous seeds across all source populations (P
< 0.001; Appendix D). There was no significant relationship
between average seed weight and source population latitude (P = 0.559;
Appendix E).