Gallego-Tévar et al. Plants Supplementary Materials

Table S1. Phenotypic expressions (additivity being equal to both parental species (Sd-Sf); additivity being intermediate between parents (A); mid-parent heterosis (MPH); best-parent heterosis (BPH); worst-parent heterosis (WPH)) for the hybrid Spartina densiflora x foliosa for 36 traits measured at different salinities (0.5, 10, 20 and 40 ppt) and inundation depths (shallow inundation (SI), 4.4 cm; Intermediate inundation (II), 35.5 cm; Deep inundation (DI), 55.0 cm deep). Parental taxa: S. densiflora (Sd); S. foliosa (Sf). Three-way ANOVA, salinity x inundation x taxa, P < 0.05, n = 4.

Table S2. Number of individuals of Spartina densiflora x foliosa (n = 4) with worst- or best-parent heterosis for 36 traits measured at each treatment combination of salinities (0.5, 10, 20 and 40 ppt) and inundation depths (shallow inundation (SI), 4.4 cm deep; intermediate inundation (II), 35.5 cm deep; deep inundation (DI), 55.0 cm deep). Percentages of individuals are marked in bold.

Figure S1: Pictures of individuals of Spartina foliosa, S. densiflora x foliosa and S. densiflora (from left to right for each inundation treatment) after 44 days under shallow (SI, 4.4 cm deep), intermediate (II, 35.5 cm deep) and deep inundation (DI, 55.0 cm deep) and exposed to (A) 0.5 ppt salinity and (B) 40 ppt salinity.

Figure S2. Split-plot, full factorial experiment design in which salinity was assigned as the main plot in a randomized complete block design, inundation was assigned to the subplots, and the three taxa (n = 4 plants per treatment) were nested within each subplot. Salinity treatments (large plots): 0.5 (yellow), 10 (purple), 20 (ocher) and 40 ppt (green). Inundation treatments (small plots): shallow (doted brown), intermediate (dark blue), deep (dark to light blue). Spartina taxa (circles): S. foliosa (orange), S. densiflora (green), S. foliosa x densiflora (yellow).