Selecting for Seed Size Diversity Can Support a Variety of Plant Colonization Strategies in Caatinga Restoration

ABSTRACT

Seed traits offer valuable insights into colonization strategies under climatic unpredictability. In seasonally dry tropical forests, such traits help explain species adaptations to water availability, which is critical for effective restoration. This study analyzed seeds from 22 native species in a Brazilian dry forest to evaluate whether trait‐based approaches can guide the selection of germination pre‐treatments for restoration purposes. Laboratory experiments using 400 seeds per species tested the effects of mechanical, chemical, and thermal scarification on germination performance. We used generalized linear models to evaluate treatment effects on germination for each species and to test how seed size and water content predict dormancy, while generalized linear mixed models tested whether these seed traits influence the efficacy of pre‐treatments. Seed sizes ranged from 5.5 to 2483.2 mg/seed ⁻¹ , with water content between 4.8% and 16.3%. Nine species exhibited physical dormancy, while thirteen lacked physical dormancy. Germination percentage increased with seed size following seed coat scarification. Small seeds germinated fast and synchronously in response to mechanical and chemical treatments, whereas larger seeds showed slow and non‐synchronous germination. These patterns suggest that seed size reflects germination strategies and can inform the selection of effective pre‐treatments. Trait‐based approaches may enhance restoration outcomes by accelerating germination of stored seeds. Incorporating a range of seed sizes can support varied regeneration strategies, with non‐synchronous germination helping species cope with rainfall unpredictability and optimize establishment during favorable conditions.