Abstract
Because germination is a key to the regeneration and restoration of tropical rain forests and because the Luquillo Experimental Forest (LEF) of Puerto Rico is among the most studied rain forests in the world, the germination requirements of LEF trees were reviewed from field and greenhouse studies. A table is included summarizing germination percentage, conditions and environmental cues (soil moisture content, light and temperature) for >150 species. The review showed that (1) studies are still needed for many of the common tropical genera, (2) most species showed a consistency of cues across several LEF studies with some plasticity, implying that regeneration niches exist and could be used for restoration efforts, and (3) many species demonstrated a clear relationship between germination requirements and successional status and life-history traits (e.g. higher germination with less light and more plastic responses with successional stage). However, the lack of consistent patterns for some species points to the need for more exploration of variation in tropical germinations cues, which may include 'hidden' seed dormancy. Finally, tropical and temperate germination are contrasted, and guidelines suggested for future tropical regeneration and restoration research.
