Results

Germination and influence of temperature treatments

Overall, the experiment found low germination rates across all temperature treatments with ~2 % (n = 44) of seeds germinating from ambient locations and ~4 % (n = 73) of seeds germinating from thermally affected locations despite viability from all locations being >95 %. There were significant differences in mean time to germination, germination likelihood and the number of dead seeds depending on if seeds were sourced from thermally affected sites or if they were from ambient sites.

Mean time to germination

There was no difference in mean time to germination (MTG) between the two different sampling years. Cox models identified that the 16°C treatment germinated significantly faster than all other treatments (Figure 2; Table 1; p < 0.001). Seeds sourced from plants living in thermally affected sites germinated faster (46.4 ± 5.7 days) compared to seeds from ambient locations (52.7 ± 7.3 days) (p = < 0.001; Table 1, Figure 3). Further, seeds in salinities of 8 ppt germinated faster than those in 32 ppt, however there were no interactions between salinity and location or salinity and treatment.