Germination cues and community assembly in a coastal habitat

Regeneration by seed is a critical process in the life of plants, and germination traits determine the environments that a species can inhabit. Fernández-Pascual et al. study the germination of thirty species from the western European coastline.

Differences in the seed germination niche among plant communities
Differences in the seed germination niche among plant communities. Germination niche shape was estimated as the best temperature for seed germination. Germination niche breadth was measured with Pielou’s evenness index (logit-transformed); higher values indicate broader niches. Only significant differences are shown, as indicated by phylogenetic generalized least squares (PGLS) minimal adequate models (Table 2). Bars represent the mean value of each group as estimated by PGLS, and brackets represent s.e. SB, seawards beaches; LB, landwards beaches; SC, seawards cliffs; LC, landwards cliffs.

They observe that cliff species germinate at low temperatures to prevent emergence during summer drought, while beach plants wait for warm temperatures and hence avoid winter gales. Shifting dune plants, which live in the harshest environment, need more specific germination cues than fixed dune plants. These results highlight the importance of germination traits to inform plant community assembly in coastal environments.

Reference List

Fernández-Pascual, E., Pérez-Arcoiza, A., Prieto, J. A., & Díaz, T. E. (2017). Environmental filtering drives the shape and breadth of the seed germination niche in coastal plant communities. Annals of Botany, 119(7), 1169–1177. https://doi.org/10.1093/aob/mcx005